Dear friends,
Thank you for all your letters and enquiries. Pertaining to your question on eggs requesting my comments, sometime back someone asked me the same question about its effect on health. I have already written and replied to him or her in a lengthy article on this, supporting the nutritive and health benefits of eggs. I also gave scientific updates on more recent findings some of which are correctly given here as sent to me.
However the author of the article e-mailed to me, need to give at least some references of papers published in scientific journals to support the claims.
But just to super-summarize in just 13 lines without me having to go all over again explaining the complexities of physiology, biochemistry, nutritional pathogenesis related to eggs to repeat and waste time again, below are the yes points about eggs in human nutrition. But I have to leave out some minor no points since the positive benefits far outweigh its negative values.
1. Eggs and milk are among the best foods for the body especially to a growing child.
2. Eggs do not cause an elevation of blood cholesterol
3. Eggs do not clog up the coronary vessels as once thought. In fact the opposite is now true
4. Eggs are low in energy value, and is a factor to consider in the formulation of a caloric-restriction diet
5. Eggs protein quality is extremely high, and has a very high nitrogen-retention value. Hence it is extremely useful in post-surgical care, trauma, and in post-management of hypovolemic shock against negative nitrogen balance
6. Eggs contain vitamin D in its natural form. The benefits of vitamin D require several chapters on human nutrition in medicine to discuss. And I refuse to repeat
7. Eggs are cancer-protective, especially for breast cancer
8. Eggs are very rich in sulfur-containing amino acids methionine which is a very crucial amino-acid in blocking damaging free radicals. These are directly linked to the pathogenesis of heart disease, cancers, DNA damage, and all degenerative disorders, and accelerated aging.
9. Eggs protect against fatty liver, slow growth, macular degeneration (degeneration of the macula area of the retina in the eyes. This is responsible for central vision for reading, face recognition and detailed vision), edema (water retention), and various skin lesions
10. Eggs promote healthy growth of nails, hair and skin
11. Eggs are rich in tryphophan, selenium, iodine, and riboflavin (vitamin B2)
12. Eggs selenium content is cardio-protective against Keshan disease, cardiomyopathies (diseases involving the heart muscles, cardiomegaly (enlarged heart), myocardial dysfunction (poor heart function) and death from heart failure.
13. Eggs are protective against Kashin-Beck disease (osteoarthropathy), myxedematous endemic cretinism (mental retardation)
14. The list goes on…on!
Regards, and ask me no more on eggs. I have lots of other questions awaiting answers.
jb lim
4:35 a.m.
24 August, 2010
Tuesday, August 31, 2010
More on Protein Quality
Dear friends,
Thank you for your so many compliments on my previous article. Maybe I was just too harsh to prescribe laws on what is good, and what is nutritionally inadvisable.
I was just trying to tell you nutritional truth about collagen and gelatin as its by-products on hydrolysis after boiling and cooking
Perhaps I may have given the wrong message by giving the impression that chicken, duck’s and pig trotters should not be eaten because of their poor protein biological value of zero or almost zero compared to reference protein from whole eggs and milk with a score of 100 which is the maximum biological and chemical score. Thus whole egg is used as a reference to compare the quality of all other proteins
These are scores nutritionists use to evaluate the quality of proteins by their limiting amino acids. In order to have a high score, all the essential amino acids must be there, else if one is missing or are present only small amounts – what we call ‘limiting amino-acids’ then the body is incapable of retaining it for growth, repair and development. If a particular amino acid is missing or not present in sufficient quantity, then its biological value and chemical score goes down from 100 (maximum) to zero as in the case of collagen and gelatin.
Limiting Amino Acids:
The measurement of protein quality is a very highly technical subject, and also very difficult to understand for those are not trained in nutritional medicine, nutritional biochemistry or clinical physiology. But I shall try to make it very simple to understand for the lay person using the analogy of a wooden water barrel made of wooden ribs sealing it from top to bottom.
Imagine this barrel is complete with all the ribs complete and intact. Such a barrel can contain water, wine or oil right to the brim. Imagine there are 9 ribs, each representing an essential amino acid to make the barrel complete (complete protein like whole egg protein). Suppose one of the ribs is broken somewhere at the top, say 10 % from the top with 90 % still intact from the bottom.
In that case, no matter how perfect the remaining 8 ribs are, it can only hold water up to 90 % of its maximum capacity. You can even pour the entire Pacific Ocean into that barrel; still it can only remain 90 % full at maximum. The rest of the water just leached out from 10 % of the broken rib. The lower the broken rib, the less water it can contain. Thus the ‘limiting amino acid’ to measure the quality of the protein to retain nitrogen in the body, is the ‘limiting level of the rib’ to hold water in that barrel. This measures the quality of that water barrel.
The meaning of ‘limiting amino acids’:
Please note that in a protein, it does not mean that all the amino acids in there are all complete (all the ribs in perfect condition), except with one amino-acid missing or partly complete. This is not true. In a protein all the amino acids may be there, or may not be there. They may be present in different levels as if they are the barrel ribs broken or partly complete at different levels. But the amino acid that has the lowest content among the rest, is the one that limits the value of that particular protein. That specific amino acid with the lowest content among all of them, or is completely absent in the protein, is called the limiting amino acid. In short, it is liken a water barrel with several incomplete ribs, but it is the rib that is the lowest that limits the barrel to contain water only up to that level. That is the meaning of ‘limiting’.
The brains of the Jews:
It is as simple to understand as that. Unfortunately when I was a postgraduate student in London, this was taught to us in a highly technical manner with so many mathematical and biological models to grabble in the calculations. It was really complex and highly intricate, and we have to strain our brains to the maximum capacity to understand and how to calculate both the quality and quantity of protein values, their absorption, retention and their metabolic utilization. It gave us all students a lot of headache trying to understand this world expert on protein utilization by humans and by animals. All my course mates at London University were already highly qualified doctors and research scientists coming from various countries, but this Jewish professor’s brain who taught us, beat us all to it with his highly complex research on proteins.
The Jews who literally heads all the university departments are a highly intelligent race. They won almost all the Nobel Prizes in Science, Medicine or Physiology, Literature, Economics and Peace. They are exceptionally brilliant, and powerful. Einstein was a Jew, as an example. The Bible says they are God’s chosen people. With God protection over them, no wonder no country can defeat them whether they are settled in Israel, Middle East or even in the United States. They are such a powerful and intelligent race.
Quality more important…
This means that no matter how much protein you eat, similar to pouring the entire Pacific Ocean into that barrel, the body just cannot retain them for growth, development and repair if only one of the 8 + 2 essential amino acids out of 20 + 2 in a protein is incomplete or totally missing. The body can hold as much protein as the ‘limiting amino acids’ in the protein it prescribes and limits.
In the case of collagen, two very important essential amino-acids called lysine and tryptophan are missing even though it is rich in glycine and proline which account for about 50% of the amino acids present in collagen. But because these two very important body building amino acids are missing in collagen, it is like having a water barrel with two of its ribs completely missing. How can this barrel store any water in the same way as how the body can retain the amino acids from collagen when these two very important amino acids almost completely missing. The body has no choice but to throw it out like any sensible person will throw away a water barrel with even just one of its ribs missing or almost all missing?
Thus it is not just how much protein-rich foods you eat that is important for health, but also the type and quality of protein you choose. Hence you may eat the entire Pacific Ocean of proteins on this planet, but the body will still throw all of them away if only one of the 9 essential amino acids is completely missing. An egg or a glass of milk is far better because of their protein quality. The body will keep all of them. It is as simple to understand as that.
Hence it is not the quantity of protein foods, but also the quality as well, with whole eggs and milk right on the top. These two foods are specially designed by Mother Nature for babies and young animals that depended solely on their mother’s milk, and the protein inside an egg for the un-hatch chicken or other egg-laying animals for their growth and development. No other protein-rich foods can beat these two for their protein quality. You can clearly see how logical Mother Nature gave us for our survival immediately after birth.
This analogy I give here is 10 million times easier to understand than the complexities of protein nutrition we have to crack our brains day and night to understand with endless discussions among ourselves as postgraduate students. Thank God, we all passed with a Postgraduate Diploma in Nutrition as Internal Students from the University of London in 1966.
Net Protein Utilization:
There is another measure to evaluate the quality of protein. This is called the net protein utilization (NPU). It is measured by the ratio of amino acid converted to proteins to the ratio of amino acids supplied, but this is affected by the amount of limiting amino acids present. We will not go into that, as it is meant for nutritionists only and not for ordinary housewives and consumers to understand.
The reason why I extended this article from the previous one is that I do not want you all to think that eating collagen or gelatin is completely useless for our health and should not be eaten. The reason is because as Alice in Wonderland (Lewis Carroll) asks 'do we eat to live or live to eat'.
Severe protein deficiency is not a problem in Malaysia:
My answer to this question is very simple: both. In situations like Malaysia there is really no shortage of food and proteins these days. Unlike in some deprived communities like in some countries in Africa, people, especially the children are very deprived of valuable good protein so important for their growth, development, and against diseases. The children before they even reach one year old they were already deprived of their mother’s milk (which is the best protein) when the mother gets pregnant again before the first child can be properly nourished and brought up. They suffer severely from a protein-deficiency disorder called kwashiorkor, and often from energy-deficient as well leading to another condition called marasmus.
More often than not, they are severely malnourished on both, leading the child with marasmic-kwashiokor (protein-energy malnutrition). This leads to very high infantile mortality. These children need very high protein diet which is not available to them when the mother took them off breast milk, and feed them on dilute solutions or porridge of cereal grains of cassava or maize with hardly any protein or very poor quality protein as in maize / corn. The child simply dies or fails to thrive. This is a very serious health problem.
Over-nutrition is the problem:
But in Malaysia the situation is almost the opposite these days. In the 1950s and earlier, to the 1970s health and nutrition status in the rural areas, especially in Kelantan were almost like those in African countries, albeit not as bad. Malnutrition due to protein, energy, iron and vitamin deficiencies were quite common in the rural areas, especially among the Malays and Indians in the estates, although the Chinese in similar areas are better off. This was due to rural poverty among the Malays and Indians living in the rubber estates and oil palm plantations in the rural villages respectively. But with the overall economic improvement in the country since the 1980s the situation changes quite dramatically in recent years. Instead of suffering from various deficiency diseases as in World War II, the people in this country are now eating far too much to the extent they suffer from diseases of over-nutrition and nutritional excesses.
Hardly anyone in Malaysia suffers from any of the protein and energy deficiencies anymore. In fact they are obese due to far too much food available to them that is beyond their physiological needs.
Fair ‘to live to eat’:
It is this group of people that eating collagen-rich foods will not compromise their daily nutritional needs for adequate protein. They have excess of proteins in their diet of meat, fish, chicken, eggs, soy-beans, legumes and eggs. They do not require extra proteins. By eating chicken and duck’s legs, joints and ligaments of beef, mutton and pork, albeit has little nutritional benefits except for taste.
Thus, consumption of these foods is not going to compromise their needs for extra quality proteins. Food consumption surveys showed most Malaysians, especially in the cities and urban areas, and especially among the Chinese who have a very rich diet of fish, pork and chicken, eating collagen-rich foods is not going to make any difference to their daily protein requirements. They already have enough from other sources, and pig’s totters are just for fun eating and enjoyment and nothing more.
Holistic and Psychological health:
Just as Alice in Wonderland asks 'do we eat to live or live to eat' the answer has to be holistic to our health. It is important to realize that psychological health is just as important as physical health and health and enjoyment is part and parcel of physical, mental and social well-being. Humans are not laboratory rats and animals that can thrive well with adequate synthetic diets and water. Rats reared in the laboratory for medical, drug, toxicological testing etc can easily thrive and reproduce when kept in cages, but given adequate food in the form of synthetic nutrients and water. But man eat food, not nutrients for the sense of enjoyment, psychological and social well-being besides ‘eat to live’
There is a big difference between synthetic nutrients for rats and complete and nice-tasting foods for humans. Laboratory animals can be kept alive throughout their natural life-spans by just artificial nutrients and water, but no similar trials has been done on humans, because humans are not rats. They demand food, not nutrients.
Once again, nutritionists need to remind themselves that man eat food, not nutrients.
jb lim
-----------------------
On Sun, Jul 25, 2010 at 11:51 AM, Tan Seng Khoon ++ wrote:
Dear Dr. Lim JB,
Fantastic piece of Medical thesis. Brilliant. Absolutely brilliant, intelligent and deep are your scientific knowledge
I absolutely, completely and fully agree with you on all your views. No holes for any spear to go through. So David, your spears tak laku again.
Thank you for sharing your thoughts.
Now that the nutrition law will come into effect, you will be higher in demand in the market for your services.
This is very very good news. I think one table for all. Pig trotter a must I suppose. Ha..ha..ha...
Rgds,
khoon.
Thank you for your so many compliments on my previous article. Maybe I was just too harsh to prescribe laws on what is good, and what is nutritionally inadvisable.
I was just trying to tell you nutritional truth about collagen and gelatin as its by-products on hydrolysis after boiling and cooking
Perhaps I may have given the wrong message by giving the impression that chicken, duck’s and pig trotters should not be eaten because of their poor protein biological value of zero or almost zero compared to reference protein from whole eggs and milk with a score of 100 which is the maximum biological and chemical score. Thus whole egg is used as a reference to compare the quality of all other proteins
These are scores nutritionists use to evaluate the quality of proteins by their limiting amino acids. In order to have a high score, all the essential amino acids must be there, else if one is missing or are present only small amounts – what we call ‘limiting amino-acids’ then the body is incapable of retaining it for growth, repair and development. If a particular amino acid is missing or not present in sufficient quantity, then its biological value and chemical score goes down from 100 (maximum) to zero as in the case of collagen and gelatin.
Limiting Amino Acids:
The measurement of protein quality is a very highly technical subject, and also very difficult to understand for those are not trained in nutritional medicine, nutritional biochemistry or clinical physiology. But I shall try to make it very simple to understand for the lay person using the analogy of a wooden water barrel made of wooden ribs sealing it from top to bottom.
Imagine this barrel is complete with all the ribs complete and intact. Such a barrel can contain water, wine or oil right to the brim. Imagine there are 9 ribs, each representing an essential amino acid to make the barrel complete (complete protein like whole egg protein). Suppose one of the ribs is broken somewhere at the top, say 10 % from the top with 90 % still intact from the bottom.
In that case, no matter how perfect the remaining 8 ribs are, it can only hold water up to 90 % of its maximum capacity. You can even pour the entire Pacific Ocean into that barrel; still it can only remain 90 % full at maximum. The rest of the water just leached out from 10 % of the broken rib. The lower the broken rib, the less water it can contain. Thus the ‘limiting amino acid’ to measure the quality of the protein to retain nitrogen in the body, is the ‘limiting level of the rib’ to hold water in that barrel. This measures the quality of that water barrel.
The meaning of ‘limiting amino acids’:
Please note that in a protein, it does not mean that all the amino acids in there are all complete (all the ribs in perfect condition), except with one amino-acid missing or partly complete. This is not true. In a protein all the amino acids may be there, or may not be there. They may be present in different levels as if they are the barrel ribs broken or partly complete at different levels. But the amino acid that has the lowest content among the rest, is the one that limits the value of that particular protein. That specific amino acid with the lowest content among all of them, or is completely absent in the protein, is called the limiting amino acid. In short, it is liken a water barrel with several incomplete ribs, but it is the rib that is the lowest that limits the barrel to contain water only up to that level. That is the meaning of ‘limiting’.
The brains of the Jews:
It is as simple to understand as that. Unfortunately when I was a postgraduate student in London, this was taught to us in a highly technical manner with so many mathematical and biological models to grabble in the calculations. It was really complex and highly intricate, and we have to strain our brains to the maximum capacity to understand and how to calculate both the quality and quantity of protein values, their absorption, retention and their metabolic utilization. It gave us all students a lot of headache trying to understand this world expert on protein utilization by humans and by animals. All my course mates at London University were already highly qualified doctors and research scientists coming from various countries, but this Jewish professor’s brain who taught us, beat us all to it with his highly complex research on proteins.
The Jews who literally heads all the university departments are a highly intelligent race. They won almost all the Nobel Prizes in Science, Medicine or Physiology, Literature, Economics and Peace. They are exceptionally brilliant, and powerful. Einstein was a Jew, as an example. The Bible says they are God’s chosen people. With God protection over them, no wonder no country can defeat them whether they are settled in Israel, Middle East or even in the United States. They are such a powerful and intelligent race.
Quality more important…
This means that no matter how much protein you eat, similar to pouring the entire Pacific Ocean into that barrel, the body just cannot retain them for growth, development and repair if only one of the 8 + 2 essential amino acids out of 20 + 2 in a protein is incomplete or totally missing. The body can hold as much protein as the ‘limiting amino acids’ in the protein it prescribes and limits.
In the case of collagen, two very important essential amino-acids called lysine and tryptophan are missing even though it is rich in glycine and proline which account for about 50% of the amino acids present in collagen. But because these two very important body building amino acids are missing in collagen, it is like having a water barrel with two of its ribs completely missing. How can this barrel store any water in the same way as how the body can retain the amino acids from collagen when these two very important amino acids almost completely missing. The body has no choice but to throw it out like any sensible person will throw away a water barrel with even just one of its ribs missing or almost all missing?
Thus it is not just how much protein-rich foods you eat that is important for health, but also the type and quality of protein you choose. Hence you may eat the entire Pacific Ocean of proteins on this planet, but the body will still throw all of them away if only one of the 9 essential amino acids is completely missing. An egg or a glass of milk is far better because of their protein quality. The body will keep all of them. It is as simple to understand as that.
Hence it is not the quantity of protein foods, but also the quality as well, with whole eggs and milk right on the top. These two foods are specially designed by Mother Nature for babies and young animals that depended solely on their mother’s milk, and the protein inside an egg for the un-hatch chicken or other egg-laying animals for their growth and development. No other protein-rich foods can beat these two for their protein quality. You can clearly see how logical Mother Nature gave us for our survival immediately after birth.
This analogy I give here is 10 million times easier to understand than the complexities of protein nutrition we have to crack our brains day and night to understand with endless discussions among ourselves as postgraduate students. Thank God, we all passed with a Postgraduate Diploma in Nutrition as Internal Students from the University of London in 1966.
Net Protein Utilization:
There is another measure to evaluate the quality of protein. This is called the net protein utilization (NPU). It is measured by the ratio of amino acid converted to proteins to the ratio of amino acids supplied, but this is affected by the amount of limiting amino acids present. We will not go into that, as it is meant for nutritionists only and not for ordinary housewives and consumers to understand.
The reason why I extended this article from the previous one is that I do not want you all to think that eating collagen or gelatin is completely useless for our health and should not be eaten. The reason is because as Alice in Wonderland (Lewis Carroll) asks 'do we eat to live or live to eat'.
Severe protein deficiency is not a problem in Malaysia:
My answer to this question is very simple: both. In situations like Malaysia there is really no shortage of food and proteins these days. Unlike in some deprived communities like in some countries in Africa, people, especially the children are very deprived of valuable good protein so important for their growth, development, and against diseases. The children before they even reach one year old they were already deprived of their mother’s milk (which is the best protein) when the mother gets pregnant again before the first child can be properly nourished and brought up. They suffer severely from a protein-deficiency disorder called kwashiorkor, and often from energy-deficient as well leading to another condition called marasmus.
More often than not, they are severely malnourished on both, leading the child with marasmic-kwashiokor (protein-energy malnutrition). This leads to very high infantile mortality. These children need very high protein diet which is not available to them when the mother took them off breast milk, and feed them on dilute solutions or porridge of cereal grains of cassava or maize with hardly any protein or very poor quality protein as in maize / corn. The child simply dies or fails to thrive. This is a very serious health problem.
Over-nutrition is the problem:
But in Malaysia the situation is almost the opposite these days. In the 1950s and earlier, to the 1970s health and nutrition status in the rural areas, especially in Kelantan were almost like those in African countries, albeit not as bad. Malnutrition due to protein, energy, iron and vitamin deficiencies were quite common in the rural areas, especially among the Malays and Indians in the estates, although the Chinese in similar areas are better off. This was due to rural poverty among the Malays and Indians living in the rubber estates and oil palm plantations in the rural villages respectively. But with the overall economic improvement in the country since the 1980s the situation changes quite dramatically in recent years. Instead of suffering from various deficiency diseases as in World War II, the people in this country are now eating far too much to the extent they suffer from diseases of over-nutrition and nutritional excesses.
Hardly anyone in Malaysia suffers from any of the protein and energy deficiencies anymore. In fact they are obese due to far too much food available to them that is beyond their physiological needs.
Fair ‘to live to eat’:
It is this group of people that eating collagen-rich foods will not compromise their daily nutritional needs for adequate protein. They have excess of proteins in their diet of meat, fish, chicken, eggs, soy-beans, legumes and eggs. They do not require extra proteins. By eating chicken and duck’s legs, joints and ligaments of beef, mutton and pork, albeit has little nutritional benefits except for taste.
Thus, consumption of these foods is not going to compromise their needs for extra quality proteins. Food consumption surveys showed most Malaysians, especially in the cities and urban areas, and especially among the Chinese who have a very rich diet of fish, pork and chicken, eating collagen-rich foods is not going to make any difference to their daily protein requirements. They already have enough from other sources, and pig’s totters are just for fun eating and enjoyment and nothing more.
Holistic and Psychological health:
Just as Alice in Wonderland asks 'do we eat to live or live to eat' the answer has to be holistic to our health. It is important to realize that psychological health is just as important as physical health and health and enjoyment is part and parcel of physical, mental and social well-being. Humans are not laboratory rats and animals that can thrive well with adequate synthetic diets and water. Rats reared in the laboratory for medical, drug, toxicological testing etc can easily thrive and reproduce when kept in cages, but given adequate food in the form of synthetic nutrients and water. But man eat food, not nutrients for the sense of enjoyment, psychological and social well-being besides ‘eat to live’
There is a big difference between synthetic nutrients for rats and complete and nice-tasting foods for humans. Laboratory animals can be kept alive throughout their natural life-spans by just artificial nutrients and water, but no similar trials has been done on humans, because humans are not rats. They demand food, not nutrients.
Once again, nutritionists need to remind themselves that man eat food, not nutrients.
jb lim
-----------------------
On Sun, Jul 25, 2010 at 11:51 AM, Tan Seng Khoon ++
Dear Dr. Lim JB,
Fantastic piece of Medical thesis. Brilliant. Absolutely brilliant, intelligent and deep are your scientific knowledge
I absolutely, completely and fully agree with you on all your views. No holes for any spear to go through. So David, your spears tak laku again.
Thank you for sharing your thoughts.
Now that the nutrition law will come into effect, you will be higher in demand in the market for your services.
This is very very good news. I think one table for all. Pig trotter a must I suppose. Ha..ha..ha...
Rgds,
khoon.
Monday, August 30, 2010
Would boiling or frying an egg damage it nutritive value?
Question:
An e-mail enquiry was received from Mr. Tan Khoon Seng as follows:
Concerning all those good things said about eggs and nutrients, may I know if they are destroyed if the egg is hard boiled or fried? Frying is intense heat. Will the heat destroy the good stuffs?
We can see that the albumin and yolk protein hardens when heated. So its structure is changed. Will these changes harm the natural good nutrients in eggs? If not, why not?
Your comment will be greatly appreciated.
Regards
Khoon
Answer:
Physical, not chemical changes to eggs:
No! Moderate heat over a short time like boiling an egg for 2 minutes, or lightly fry an egg does not alter its nutritive values. Heat merely alters the physical properties of egg protein by coagulating its albumin, but this does not change it nutritive values.
However high heat and cooking the egg, especially frying it with oil in open air over a long time does cause heat damage to the proteins, and irreversibly change its nutritive values. (Digestion of Heat-damaged Egg Albumen by the Rat by Jose Valle-Riestra and Richard H. Barnes, Graduate School of Nutrition, Cornell University, Ithaca, New York 14850).
High temperatures not only physically and chemically denature the egg protein, but they also destroy almost all the vitamins, especially the heat labile B group of vitamins.
Nutritive values improve instead:
However moderate heat over short period just to cook or fry the egg on the contrary improves its nutritive value of the whole egg by inactivating a substance called avidin which is a glycoprotein found in the white of egg. This substance binds with one of the B vitamins called biotin and renders it unavailable to the body. Cooking destroys this avidin, and releases the biotin. This makes the egg more nutritive and more wholesome. However, this is compensated by the fact that the yolk contains a lot more of biotin, and it makes only a little difference even if the biotin in the white is not available because of the avidin. However, eating too much white of egg can lead to biotin deficiency.
Whole and wholesome eggs:
Egg should be eaten whole. I know of a lot of people who because of their ill-advised knowledge of nutrition throw away the best part of egg – the yolk, and eat only the white of egg.
I saw many of them doing this in front of me while we were on the same table for breakfast. Even though I did not know them as they were strangers on the same table, I still asked them why. They told me the yolk contains cholesterol and it causes heart disease. I then asked them how they knew that egg yolk contains cholesterol. They replied they got it from the Internet.
I then asked them why they thought that eating eggs high in cholesterol causes heart disease. They told me they also read this from the Internet. That’s the problem of people looking up information from the Internet instead of seeking the advice of a qualified health-care professional. I have previously written a lot on the myth of cholesterol, CHD, and health, and cited huge studies having concluded that dietary cholesterol neither raise or decrease blood lipids and serum cholesterol, and that ischemic heart disease is faintly correlated to elevated blood lipids. This was the conclusion in the follow up study from the immensely huge and longitudinal Framingham Heart Study. I don’t intend to repeat it anymore.
Raw and boiled eggs:
There is also some difference in the digestibility between raw and cooked egg in humans as assessed by stable isotope techniques. The study was conducted by Pieter Evenepoel, Benny Geypens, Anja Luypaerts, Martin Hiele, Yvo Ghoos, and Paul Rutgeerts from the Department of Medicine, Division of Gastroenterology and Gastrointestinal Research Centre, University Hospital Leuven, B-3000 Leuven, Belgium.
They used 15N-dilution technique to demonstrate that the assimilation of cooked egg protein is efficient, albeit incomplete, and that the true ileal digestibility of egg protein is significantly enhanced by heat-pretreatment. A simple 13C-breath test technique furthermore proved to be a suitable alternative for the evaluation of the true ileal digestibility of egg protein.
However others claimed the opposite that cooked eggs are more digestible than raw eggs. However, they did not cite the literature where the studies were conducted. Every claim needs research and evidence-based studies
Avidin:
Except for this slight statistical difference on protein bio availability, eggs to the best of my professional opinion are equally nutritious whether eaten raw, or lightly cooked, except for the presence of a glycoprotein called avidin which blocks the bioavailability of a vitamin called biotin. Biotin is a member of the B group of vitamins. The cooking process deactivates the avidin in the egg, allowing biotin to be made available to the body.
The avidin-biotin blockage in the white of eggs is compensated by its yolk which is very rich in biotin. In fact the yolk contains one of the highest biotin content among all foods. Hence it is wise to eat the entire egg, the yolk and white together. Even the shell is a rich source of calcium. In fact it is so rich in calcium that traditional beliefs (as told to me by my mother when I was a child), that eating egg shell may cause may cause the flow of urine to be blocked.
This does make scientific sense to me as I see it now. The difficulty of micturition (urination) may be caused by renal calculi (stones in the kidneys) passing down into the urinary tract caused by excessive calcium leaching out into the urine and blocking the urinary passage-way with calcium stones. Of course I am aware of other causes impeding the flow of urine, like benign prostatic hyperplasia (BHP) or prostate enlargement. But we are not talking about this here. This is an irrelevant topic here.
Biotin deficiency:
Thus it may be true that eating too many raw egg whites by themselves may cause biotin deficiency, which is normally missed out in the diagnosis by doctors who are not competent in nutritional disorders unless they have additional postgraduate degrees in clinical nutrition to be clinically competent in nutritional medicine. In fact the assessment of nutritional status is one of the hardest and most challenging fields of medicine and even for a very well qualified and expert nutritionist.
Salmonella in eggs:
An added advantage of cooking an egg reasonably well, but not over fry it, is that it may prevent the risk of a food poisoning caused by a bacterial infection called salmonella. This is a serious health risk. Salmonella are gram stain-negative intracellular anaerobes (microbes) that cause a wide spectrum of gastrointestinal diseases. They include gastroenteritis, enteric fever (caused by typhoid and paratyphoid serotypes), bacteremia, focal infections, to a convalescent lifetime carrier state. The type of infection depends on the serotype of Salmonella and host factors. Each type is distinctly identifiable by its specific protein coating. They are known to cause disease in humans, animals, and birds (especially poultry) worldwide.
No more about eggs please!
Kindly do not ask me anymore things about eggs as I have a lot of other things I want to complete writing on other subjects and other work to do, but unable to do so because of all these distractions. My mails contain too many questions people ask off and on.
jb lim
An e-mail enquiry was received from Mr. Tan Khoon Seng as follows:
Concerning all those good things said about eggs and nutrients, may I know if they are destroyed if the egg is hard boiled or fried? Frying is intense heat. Will the heat destroy the good stuffs?
We can see that the albumin and yolk protein hardens when heated. So its structure is changed. Will these changes harm the natural good nutrients in eggs? If not, why not?
Your comment will be greatly appreciated.
Regards
Khoon
Answer:
Physical, not chemical changes to eggs:
No! Moderate heat over a short time like boiling an egg for 2 minutes, or lightly fry an egg does not alter its nutritive values. Heat merely alters the physical properties of egg protein by coagulating its albumin, but this does not change it nutritive values.
However high heat and cooking the egg, especially frying it with oil in open air over a long time does cause heat damage to the proteins, and irreversibly change its nutritive values. (Digestion of Heat-damaged Egg Albumen by the Rat by Jose Valle-Riestra and Richard H. Barnes, Graduate School of Nutrition, Cornell University, Ithaca, New York 14850).
High temperatures not only physically and chemically denature the egg protein, but they also destroy almost all the vitamins, especially the heat labile B group of vitamins.
Nutritive values improve instead:
However moderate heat over short period just to cook or fry the egg on the contrary improves its nutritive value of the whole egg by inactivating a substance called avidin which is a glycoprotein found in the white of egg. This substance binds with one of the B vitamins called biotin and renders it unavailable to the body. Cooking destroys this avidin, and releases the biotin. This makes the egg more nutritive and more wholesome. However, this is compensated by the fact that the yolk contains a lot more of biotin, and it makes only a little difference even if the biotin in the white is not available because of the avidin. However, eating too much white of egg can lead to biotin deficiency.
Whole and wholesome eggs:
Egg should be eaten whole. I know of a lot of people who because of their ill-advised knowledge of nutrition throw away the best part of egg – the yolk, and eat only the white of egg.
I saw many of them doing this in front of me while we were on the same table for breakfast. Even though I did not know them as they were strangers on the same table, I still asked them why. They told me the yolk contains cholesterol and it causes heart disease. I then asked them how they knew that egg yolk contains cholesterol. They replied they got it from the Internet.
I then asked them why they thought that eating eggs high in cholesterol causes heart disease. They told me they also read this from the Internet. That’s the problem of people looking up information from the Internet instead of seeking the advice of a qualified health-care professional. I have previously written a lot on the myth of cholesterol, CHD, and health, and cited huge studies having concluded that dietary cholesterol neither raise or decrease blood lipids and serum cholesterol, and that ischemic heart disease is faintly correlated to elevated blood lipids. This was the conclusion in the follow up study from the immensely huge and longitudinal Framingham Heart Study. I don’t intend to repeat it anymore.
Raw and boiled eggs:
There is also some difference in the digestibility between raw and cooked egg in humans as assessed by stable isotope techniques. The study was conducted by Pieter Evenepoel, Benny Geypens, Anja Luypaerts, Martin Hiele, Yvo Ghoos, and Paul Rutgeerts from the Department of Medicine, Division of Gastroenterology and Gastrointestinal Research Centre, University Hospital Leuven, B-3000 Leuven, Belgium.
They used 15N-dilution technique to demonstrate that the assimilation of cooked egg protein is efficient, albeit incomplete, and that the true ileal digestibility of egg protein is significantly enhanced by heat-pretreatment. A simple 13C-breath test technique furthermore proved to be a suitable alternative for the evaluation of the true ileal digestibility of egg protein.
However others claimed the opposite that cooked eggs are more digestible than raw eggs. However, they did not cite the literature where the studies were conducted. Every claim needs research and evidence-based studies
Avidin:
Except for this slight statistical difference on protein bio availability, eggs to the best of my professional opinion are equally nutritious whether eaten raw, or lightly cooked, except for the presence of a glycoprotein called avidin which blocks the bioavailability of a vitamin called biotin. Biotin is a member of the B group of vitamins. The cooking process deactivates the avidin in the egg, allowing biotin to be made available to the body.
The avidin-biotin blockage in the white of eggs is compensated by its yolk which is very rich in biotin. In fact the yolk contains one of the highest biotin content among all foods. Hence it is wise to eat the entire egg, the yolk and white together. Even the shell is a rich source of calcium. In fact it is so rich in calcium that traditional beliefs (as told to me by my mother when I was a child), that eating egg shell may cause may cause the flow of urine to be blocked.
This does make scientific sense to me as I see it now. The difficulty of micturition (urination) may be caused by renal calculi (stones in the kidneys) passing down into the urinary tract caused by excessive calcium leaching out into the urine and blocking the urinary passage-way with calcium stones. Of course I am aware of other causes impeding the flow of urine, like benign prostatic hyperplasia (BHP) or prostate enlargement. But we are not talking about this here. This is an irrelevant topic here.
Biotin deficiency:
Thus it may be true that eating too many raw egg whites by themselves may cause biotin deficiency, which is normally missed out in the diagnosis by doctors who are not competent in nutritional disorders unless they have additional postgraduate degrees in clinical nutrition to be clinically competent in nutritional medicine. In fact the assessment of nutritional status is one of the hardest and most challenging fields of medicine and even for a very well qualified and expert nutritionist.
Salmonella in eggs:
An added advantage of cooking an egg reasonably well, but not over fry it, is that it may prevent the risk of a food poisoning caused by a bacterial infection called salmonella. This is a serious health risk. Salmonella are gram stain-negative intracellular anaerobes (microbes) that cause a wide spectrum of gastrointestinal diseases. They include gastroenteritis, enteric fever (caused by typhoid and paratyphoid serotypes), bacteremia, focal infections, to a convalescent lifetime carrier state. The type of infection depends on the serotype of Salmonella and host factors. Each type is distinctly identifiable by its specific protein coating. They are known to cause disease in humans, animals, and birds (especially poultry) worldwide.
No more about eggs please!
Kindly do not ask me anymore things about eggs as I have a lot of other things I want to complete writing on other subjects and other work to do, but unable to do so because of all these distractions. My mails contain too many questions people ask off and on.
jb lim
Sunday, August 15, 2010
Furadan in watermelon? An Analysis & Comment by jb lim
Dear Dr Lim,
Is the info below true?
Furadan in watermelon! Pictures and warning in attachment.
I would like to hear your comments.
Thank you and regards,
Helen
-------------------------------------------------------------
JB Lim's reply to
Helen Tee Guat Hiong
Scientist and Colleague
Formerly, Institute for Medical Research
Currently, Public Health Institute
Ministry of Health Malaysia
Dear Helen,
Thank you very much for your enquiry on the presence of Furadan in watermelon. I have received the same e-mail warnings from many other e-mailers like Ms. Annie Lee, Ir. Tai Onn Lau, Dr Ganeshadeva Muthu Ramalingamm and Ms Josephine Wong, among others.
Thank you to all of you who have written to me about the presence of Furadan-laced watermelons.
This story and warning has also appeared in a few websites and blogs. The following are my analysis and critical opinion
It really beats me to understand whoever puts that piece of warning about watermelon being laced with Furadan (Carbofuran) should specifically target watermelon as the only fruit to be cautioned about the presence of this chemicals. Why only watermelon? Why not in papaya, banana, pineapple, star fruit, dragon fruit, pomelo, and so on? Why single out watermelon only? It really beats my understanding. To make it even more unconvincing, at least to a scientific mind, no data as evidence was given. There was not a single report of a chemical analysis done to actually show the amount of Furadan present in the watermelon, let alone compare the data on amount with other fruits and vegetables. What I receive from this chain e-mails is just a bunch of absolute rubbish without any evidence given.
Evidence-based:
Not a single data from chemical analysis was give. It was just claims, claims, and highly unscientific claims to discredit watermelons and the farmers that all. To produce such a claim in a Court of Justice without a single shred of data or evidence, would instantly, not only just thrown out, but the claimant would be asked to pay with cost for damage and compensation to the watermelon producers. All claims must produce data, data and evidences. Don’t just claim by cooking up a story and send them out through chain mails to confuse and deceive the less educated. Not every recipient of chain e-mails are morons, imbecile and idiotic.
Difficult without food analysis report:
But this does not imply that watermelon or any fruits and vegetables are not laced with Furadan if farmers deliberately add them to kill off pests. What I am asking is for people to show proof and evidences. That all I am asking. Even if they spray the crops with Furadan or any pesticides, this does not mean the watermelon, or any other fruits and vegetables harbor them. They must show the data and report of a chemical analysis from a credited and registered laboratory, and the report need to be carried out and signed by a qualified Chemist or a Food Quality Controller whose university degree in Analytical Chemistry must be registrable with the Malaysian Institute of Chemistry under the Chemist Act 1975. Less than that, are all rubbish reports and claims.
Furadan broad spectrum action:
In the best of my understanding, Furadan is a broad spectrum carbamate pesticide that kills insects, mites, and nematodes on contact or after ingestion. It has a potential to cause damage to the reproductive system to all pest, and probably to the health of humans as well by prolonged and chronic exposure. Carbofuran is not alone in the list of pesticides where its widespread use in agriculture that has caused severe environmental pollution and public health risk.
Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) generally called as Furadan is a broad spectrum carbamate compound which has been used against soil and foliar pests of field, fruit, vegetable, and forest crops. So why only on watermelon as the e-mail has portrayed to mislead consumers and the public. Whoever started it must have a grudge against watermelon farmers, probable those in Cameron Highlands. I think they are out to sabotage their livelihood.
Toxicity:
Carbofuran is highly toxic by inhalation and ingestion and moderately toxic by dermal absorption. But this is also true with many other pesticides. So why only specifically target on carbofuran and watermelon? But I really failed to understand why many e-mailers are out only to mislead others by inventing stories to pass them on to others through their chain e-mails. I receive this from a friend and former colleague for my comment.
Most of the pesticides, especially the organophosphate insecticides, work by interfering with the electrochemical mechanism that nerves use to communicate with muscles and with one another. A key chemical in this communication between synapses is neurotransmitter called acetylcholine. .This chemical produced by the body is used to "fire" the neuron, and this in turn contracts a muscle such as the high frequency flapping of the wings of an insect. Acetylcholine is then inhibited by an enzyme called cholinesterase to prevent further contraction so that the insect can rest.
Toxicodynamics of pesticides (mode of action):
These pesticides lock or block the action of cholinesterase so that it can no longer inactivate the acetylcholine. As the acetylcholine builds up, the muscles of the body become over-stimulated, leading to paralysis and death. The insect literally dies of exhaustion. This mode of action of a pesticide, or in some drug action, we called it the ‘key and lock’ theory. That is how they act on insects by preventing cholinesterase from erasing the acetylcholine to exhaust their muscular activity. It is in this way classified as a neurotoxin.
Carbamate insecticides have similar toxic mechanisms to organophosphates, but have a much shorter duration of action and are thus somewhat less toxic. However, other feel that it has the highest acute toxicity to humans of any insecticide widely used on field crops. A quarter teaspoon (1 mL) is said to be fatal. Most carbofuran is applied by commercial applicators using closed systems with engineered controls, so that there is no exposure to the chemical through pouring or measuring. Whatever the level of toxicity, it remains true that all pesticides need to be handled with care, including Furadan.
Paraquat mode of action:
This mode of action of an insecticide (pesticide) s different from that of a Paraquat which is not an insecticide but is a weed-killer. Weeds may also be considered as a plant pest, and in this way it is also a pest to a farmer.
Paraquat inhibits photosynthesis. In light-exposed plants, it transfers electrons to molecular oxygen to form highly destructive reactive free radicals. The oxidized form of paraquat is regenerated to shunt electrons from photo system I to start the cycle again. Another way of putting it, is that it involves diverting the flow of energy captured from sunlight in photosynthesis to produce highly reactive free radicals which destroy cell membranes to quickly desiccate leaves. This happens within hours in bright sunlight because of its high energy levels.
Pesticides may also induce oxidative stress, leading to generation of free radicals and alteration in antioxidants, oxygen free radicals, the scavenging enzyme system, and lipid peroxidation (Banerjee et al. 1999, Etemadi et al. 2002).
In 2002, anti-paraquat campaigners were jubilant when, after a 10-year campaign, they succeeded in persuading the Malaysian government to clamp down on the substance. The government issued a circular that year saying that pesticides containing paraquat and calcium cyanide would not be re-registered and all forms of advertising of the two substances would be banned.
But victory for anti-paraquat campaigners lasted only four years. The government's decision now to ‘‘temporarily lift the ban'' swings the lobbying war in Syngenta's favour. The Swiss agrochemical giant, Syngenta markets this herbicide under the brand name Gramoxone, and other industry groups.
‘‘We want to do an extensive study on paraquat, its harmful effects and positive aspects, before the set date for its total ban in November next year,'' Pesticide Control Division director Nursiah Tajul Arus was quoted as saying. The Pesticides Board is now allowing registration of paraquat for all crops ‘‘to facilitate the study''.
Effect of Carbofuran on neurotransmission:
According to The US Environmental Protection Agency (EPA) carbofuran can over-stimulate the nervous system, causing nausea, dizziness. Since organophosphates bind to acetylcholinesterase and other cholinesterases, this results in disruption of nerve impulses, killing the insect or interfering with its ability to carry on normal functions. Organophosphate insecticides and chemical warfare nerve agents (such as sarin, tabun, soman and VX) work in the same way. Organophosphates have an additive toxic effect to wildlife, so multiple exposures to the chemicals amplify the toxicity. But as with other carbamate compounds, carbofuran’s cholinesterase-inhibiting effect is short term and reversible.
Carbofuran on wildlife:
Carbofuran is highly toxic to fish and birds particularly in granular form. Birds often eat them mistaken them for seeds, or through contaminated drinking water. One granule of carbofuran according to one source is enough to kill a small songbird.
EPA has banned the use of carbofuran on all food crops, not just for watermelon because it poses an real health risk, especially to children. It is marketed under the brand name Furadan This has been under EPA review for years. Its granular form was prohibited in the mid-1990s because it was blamed for killing millions of migratory birds. The agency fought to remove the pesticide from the market in 2006.
However, Furadan's manufacturer, FMC Corp. of Philadelphia, Pennsylvania, has fought the federal action. In March, the company voluntarily scaled back its uses, in hopes of preventing broader restrictions.
Pesticides in Human and Animal Health:
Currently, there are more than 865 recorded pesticides according to the Environmental Protection Agency. However, fewer than half of these pesticides are employed for agriculture in the United States and this is even less in Malaysia. Pesticides are man-made and are regulated by the U.S. Department of Agriculture, and here in Malaysia, our list is also controlled by the Malaysian Pesticide Board. However, the EPA determines how much these pesticides can be deposited on crops as well as how much of the pesticides linger on the foods being bought by consumers. Such study as far as we know is not available in Malaysia.
The toxicity of pesticides, are such that we can expect some health risks as they are intended to kill insects and pests. Some pesticides can be extremely toxic. Pesticides containing nicotine are one example. Pesticides can be harmful not only to intended insects and pests, but also to humans, animals and the environment simply because they are specially formulated to be harmful to all live organisms.
Position of pesticides usage in Malaysia:
Since 2003, the Pesticide Board of Malaysia has either totally banned, or partially banned a list of pesticides in Malaysia. A total ban was imposed on DDT, Chlordane, Heptachlor. Sodium penthachlorohenate, Endosulphan (not allowed for rice), Lindane gamma-BHC (not allowed for cocoa), Methomidophos, and Monocrotophos (not allowed for oil palm), while others such as Aldrin, Diledrin, Endrin, etc were withdrawn by the manufacturers. Endosulphan is an organochlorine, and this is completely banned in most countries, but not totally banned in Malaysia.
Biological control:
However, today, scientists have developed bio-pesticides or biologically-based pesticides and these are becoming more acceptable to the public since they are considered to be safer than the traditional chemical pesticides.
To the best of my knowledge even though Carbofuran (Furadan) was not in the list of banned pesticides in Malaysia, there has also not been any report of Carbofuran being used in the cultivation of water melon in Malaysia even though a number of countries have already banned it. In the United States for instance, this pesticides have been applied also in the cultivation of soy beans, potatoes, and corn (maize), but as far as we know, this practice is now banned.
However one report says that Carbofuran usage has increased in recent years since 2002 in most soybean-growing regions of the U.S. because it is one of the few insecticides effective on soybean aphids. We are unable to verify.
Chemical analysis needed:
Carbofuran is a systemic water soluble insecticide that can enter into the root system This means the plant absorbs it through the roots, and from there distributed to the rest of the rest of the plants mainly the vessels, stems and leaves where the insecticidal concentrations are attained. But this does not mean it has also gone into the fruit. I shall explain this later.
Although it has not been found in fruits that are fleshy such as in water melons so far, this does not mean it cannot happen. The only way to find out for sure is to do a chemical analysis on the fruit concerned. This is the only way. The rest are all guessing, rumors and fairy tales. Just show us the analytical chemical report of pesticides inside the fleshy part of a fruit which is the edible portion, not outside on the skin. Also, we need to know how much is present inside the flesh. That’s all that is needed.
Perhaps this pesticide has been used externally in the cultivation of water melons in Malaysia and elsewhere, but I don’t think we have evidence that water melon itself stores the pesticide after harvest.
Molecular weight and absorption:
Plants normally can only assimilate simple compounds of low molecular weights like carbon dioxide from the air through photosynthesis to manufacture starches and sugars, and water (hydrogen and oxygen) through the root systems, together with major macronutrients in the form of elements like nitrogen through nitrogen-fixation, meaning, conversion of atmospheric nitrogen into nitrates and nitrites, or supplied by decaying matter, nitrogen fixing bacteria, animal waste, or through the agricultural application of purpose made fertilizers, phosphorus and potassium, minor macronutrients - calcium, sulphur and magnesium, and other micronutrients like iron, molybdenum, boron, copper and manganese. All these have to be in its elemental form and not in complex compounds.
Some evidence of organic absorption:
However, there are some studies in the literature that some plants can absorb organic nitrogen, but these have to be in very simple nitrogen organic compounds of very low molecular weights like amino-acids. Using all these simple elements and water in the soil together with carbon dioxide from the air, plants manufacture all the starches, sugars, plant acids, aromatic compounds, carotenes and carotenoids, colours and all other phyto-chemicals we know off. It cannot absorb and utilize complex organic compounds such as high molecular weights pesticides, insecticides, or even fertilizers without breaking them down first into simpler elements usually with the help of soil bacteria. They just cannot pass through. There is a cellular and membrane barrier there in place to prevent undesirable substances, especially high molecular weight substances from passing through.
Systemic absorption are possible if the molecular weights of the pesticides are low, but they may be confined on the roots, stems and leaves, and in between the folds of leaves and vegetable. But so far there has been no known absorption into the fruit themselves.
Fruits and seeds are plant babies:
The watermelon, and literally all fleshy fruits which are considered a ‘baby plant’ with the seeds in there are even harder to pass through. Like all living things the mother plant (inclusive of animals) will protect its babies first. It is just a program Mother Nature has written and designed to ensure the ‘babies’ are well protected from harmful substances.
So this means it is less likely that Carbofuran, organophosphates, or other pesticides, or any other exogenous (external) organic substances not produced by the plant itself can ever get through the plant into the fruit because of a membrane barrier that selectively screened out all substances that should not be part of the fruit by nature. They just cannot get through that’s all. In fact, as far as I know, no fruit has been shown to have pesticide residues. Perhaps almost all the pesticides shown to be present are found to be on the outside of fruits, namely on the skin. These are residues left after even the fruits were sprayed with pesticides.
Accumulative poisons:
Pesticides tend to accumulate in fatty material if they are oil soluble like DDT. Hence fatty meats, fish, and dairy products will have higher pesticide residue than the low-fat products. The wax coating on cucumbers facilitates the retention of the fungicides used on cucumbers. But almost all fruits and vegetables are non-fat. So oil-soluble pesticides just cannot get into their root system of plants of fruits and vegetables since plants absorb water, not oil.
Overall, the consumption of low-fiber, fat-rich and calorie-rich diets, along with the use of alcohol, pose a much, much greater threat to human health than chemical residues on our food.
Fruits and vegetables are known to protect against heart disease and cancer. They are rich in vitamins, minerals, fiber, and health-promoting phytochemicals. However, many fruits and vegetables test positive for pesticide residues, with about one-third of them showing up with multiple residues. Research reveals that prolonged exposure to pesticide residues may increase the risk of various cancers and neurological problems (such as Parkinson's disease), and impair the immune system. It is claimed that they cause:
1. Cancer
2. Fertility problems
3. Brain tumors
4. Childhood leukemia
5. Non-Hodgkin's lymphoma
6. Birth defects
7. Irritation to skin and eyes
8. Hormone or endocrine system problems
Nervous system damage:
But so far I have not come across literature of human studies to substantiate the above claim. It is not easy to do such an experiment on humans to prove these claims. The reasons are too long and technical for me to discuss them here unless readers are medical researchers who understand toxicology, statistics, study designs, epidemiology, etc.
Nutritive values of watermelon:
Watermelon is mainly water at 92.6 percent; low in energy at just 28 kilocalories per 100 gm of the fruit. It also contains 5.50 mg vitamin C, and a good source of potassium at 78 mg. per 100 gm, and a very rich source of carotenes. This makes watermelon one of the most nutritious, health-promoting, and cancer-preventive, especially against prostate cancer fruits available. Its carotenoid content in microgram per 100 gm of watermelon is:
Crypto 457
Lycopene 5301
Gamma-carot 90
Beta-carotene 324
Carotenes 410
Sum carot: 6171
What else do we need?
Moreover, fruits, unlike vegetables are normally very fleshy. The plants do not manufacture fruits out of pesticides. I have already mentioned that plants through photosynthesis manufacture all their starches, sugars, and fleshy parts of the fruit as their food, and all other protective substances such as thousands of high molecular weights antioxidants, and photochemical with the help of just water, and all the essential simple nutrients in the form of elements taken in by the roots.
No complicated organic compounds are used for the manufacture of the fleshy parts of the plants. These pesticides are not part of their natural flesh – the fruits, including watermelon. Fruits and vegetables are made up of 99.999999 % natural biological materials produced absolutely, totally, and completely by the plants only using only water and nutrients from the soil, and carbon dioxide from the air, and energy from the Sun.
Plants are made from pesticides:
Plants inclusive of their roots, stems, flowers, fruits and seeds, and vegetables too are not made from pesticides. If they are present, they are sprayed there by man only, and after sometime, even these will suffer biodegradation leaving only very trace amounts – in parts per million on the outside of the leaves, fruits and vegetables. They normally do not get into the fleshy parts inside the plant unless the pesticides are a systemic poison, and must be water soluble.
Mainly on the surface:
Most of the residues remain outside on the leaves, stems, branches, flowers and fruits, and when they are exposed to the air and wind, light, ultra-violet rays of the Sun, heat, moisture and bacteria, these pesticides rapidly decompose even on the outside surface (skin) of the fruit.
Life span of pesticides:
I do not know the t ½ (t 50) value of Furadan, meaning the time taken for half the amount of Furadan left after decomposition, decay, biodegradation or when ingested. This is called ‘half-life’ meaning 50% of the Furadan left given by the symbol‘t ½’ or‘t 50’. This is a term used especially in pharmacology to determine the half life of a drug inside a body.
Even if Carbofuran is left in the soil, or has been sprayed onto a fruit like watermelon, the half-life will depend on many decomposition factors such as the amount of heat, light and water, their amount and intensity.
It is unlikely they can stay too long even if they are present inside the flashy part of a fruit or plant, as the living plant itself will quickly try to destroy them with their tens of hundreds of antioxidants and other phytochemicals present. These are manufactured by a plant in a plant specially to protect them. The plants too do not need these chemicals inside their body.
Antioxidants in plants:
Plants bear not just leaves, stems, flowers and fruits, but they also manufacture tens of hundreds of different antioxidants to protect themselves from free radicals, especially free oxygen (singlet oxygen) radicals produced by the ultra-violet light of the Sun as they have to remain in the Sun for at least 10 to 12 hours everyday to manufacture food for themselves through photosynthesis.
This is no joke as they have to remain immobile in the Sun especially in the hot tropical Sun for so long everyday. They cannot move into the shade like animals. So Mother Nature programmed into the plants so that they can produce tens of hundreds of different antioxidants of varying molecular weights to protect themselves from free radicals generated by the ultraviolet rays of the Sun. Most of them are very high molecular weights antioxidants of over 30,000. These are all not biologically available to humans and other animals. These antioxidants are manufactured by the plants to protect themselves and are not meant for humans and animals to take away for their own protection.
Low molecular antioxidants:
But these plants in their mercy as Mother Nature prescribes leave only a very small amounts of very low molecular weight antioxidants for humans and other animals. Their molecular weights are less than 30000 such as vitamin C, vitamin B2, carotenes, catechin, polyphenols, flavonoids. Their molecular weights are in the range of 200-400 only. These are bio-available to humans and animals as they can pass through the human intestinal gut even without ‘active transport’ across the intestinal membrane.
But we are getting so few of the huge range of antioxidants and protective phytochemicals the plants produce, maybe just less than 1 % of them. Only these, vitamin C, carotenes, bioflavonoids, etc are given to us out of mercy and kindness of the plants. We literally live on their scrapes and morsels like beggars.
The ‘selfish’ plants:
The rest of the 99.9 % of protective antioxidants the plants keep for themselves because they have to stand out in the hot Sun all day long against UV-ray generated oxygen radicals. We can remain in the shade, and are given just a little vitamin C of low molecular weight which the plants hardly need. That’s how Mother Nature works to prioritizes in order to keep all living creatures and plants alive. God is very fair.
Free radicals are also needed:
Oxygen radicals are fine and good for the body in limited qualities as when required to protect the body against infection against invading bacteria, but in excess these oxygen radicals released by the phagocytes attack not just pathogenic bacteria, but they also attack the body by damaging the cells and the DNA in them The role of the endogenous (produced within the body) radical scavengers (antioxidants) is to remove the excess free radicals from the body.
The body’s antioxidants:
There are 3 endogenous antioxidants produced by the body to combat free radicals in the body. These are: Superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-Px).
Of the 3 endogenous antioxidants, SOD is the most active in removing free radicals from the body, while catalase and GSH-Px have extremely high molecular weights, and they cannot be used for the treatment of disease even by injection. As SOD’s levels rise to fight against pathogenic invasion, this capacity to rise, called ‘induction capacity’ or ‘inducibility’ declines rapidly with age.
Only by injections:
Because SOD, catalase and GSG-Px are of such high molecular weights they just cannot pass through the intestinal gut. So some health companies synthesize these products to be given by injections to bypass the intestine.
My answer to these rubbish products produced by some of these health product companies and sell them as food supplements and even as pharmaceuticals is because these products cannot be retained by the body.
It has been shown that just 6 minutes after an injection of SOD into the body, the body starts to throw half of them out into the urine. These people who believes SOD injection is good for health in combating oxygen and peroxide radicals in the body is completely wasting their money. This is the same as those who take high doses of vitamin C in the erroneous belief that they would be retained in the body for a long time even after the blood has been saturated by them. They think that if a little vitamin does me good, a lot will do me even better? They have been brain-washed by health freaks. A little knowledge is a dangerous thing.
The protective barrier:
The body is so protective against any undesirable substances entering it, that it is far harder for them to enter (be absorbed) than it is for them to be excreted out through the kidneys into the urine. In other words the threshold of the kidney is much lower for expulsion than the much higher threshold of the intestines to absorb.
Most substances, even salts and nutrients have to be chemically pumped through the intestines, a process in physiology we call it as ‘active transport’ such as the ‘sodium pump’
It is a energy-demanding mechanism across a concentration gradient by using chemical energy such as adenosine triphosphate (ATP). In cells accumulating high concentrations of molecules that the cell needs, such as ions, glucose, amino acids they have to be chemically pumped across, or actively transported across a membrane.
Human gut barrier:
The human gut barrier bars the absorption of any high molecular substances over 30000 trying to enter the body. This is just a protective mechanism in place. All complicated organic substances including starches, complex sugars, proteins and fats need to be broken down first before entering the body for security reason. This is like stripping a person naked, and searching his body first before allowing him or her to enter through a narrow gate into a high security area. This is how God plan, architect, and program our body and the bodies of all other creatures to safe guard us on this Planet.
Not easy to get through:
So it is not so easy for toxic substances to get into the blood stream in humans even if there is no such barrier in plants bearing flowers and fruits as Nature’s first filter.
The Carbofuran or any pesticides has to cross two biologically active protective barriers – one in the plant bearing fruits and seeds as their ‘babies’ , and even if these chemicals get through in traces (perhaps in just a few parts per million or even per billion), these pesticides still have to face the human protective intestinal barrier. It is not as easy as that.
The liver detoxifying chemistry:
Even if toxins do squeeze their way into the body, the liver is there to recognize them by destroying them. In the event the liver is unable to do this because of the complexities of its molecules, it will quickly pass it on to the kidney for expulsion.
We will not go into the highly complex biochemistries of how the liver recognizes a toxin, be it Furadan or anything else, but one example will do here. The enzymes secreted by the liver are like (chemical) knives. If a highly complex molecule is presented to it, the liver will study its chemical structure first to see how it can break it down. It will examine where their weak links are.
Simple chemistry:
These normally are the covalent bonds that bind the molecular fragments together as a whole molecular structure. Once it identifies where the chemical knot is, the liver will produce the specific enzymes (the chemical knife) to cut the knot into pieces so as to loosen the entire knot (the complex molecules, toxins, drugs, etc). Once the chemical knot is cut, the whole structure loosens. The toxin / poison will instantly lose its chemical nature and identity and can no longer act as one. Even a single bond has been sliced off, the chemical nature of a substance including a toxin will be lost. It is a matter of the various enzymes of a liver to cut the various chemical knots in a molecule to render it harmless before sending it to the kidney for expulsion.
Simpler molecules:
The complex molecules will become simpler monomers or isomers or other substances so unlike its original polymer (example). They no longer become a chemical threat to the body. The liver then passes on its metabolic waste products to the kidneys to be thrown away.
This is just one simple example how the liver deals with any poison, drug, or any substance that enters the body willfully (as drugs), or unintentionally as accidental ingestion of a toxin through food. There are thousands of highly complex biochemistries going on in the liver to deal with various kinds of toxins, and we are not going into pharmacokinetics, or biochemical toxicology.
The defensive body:
‘I praise thee because I am fearfully and wonderfully made; thy works are wonderful, I know that full well’ (Psalm 139:14). Truly, the body is fearfully and wonderfully made by God to do this job to protect us. The liver together with the kidneys can easily handle toxins and drugs most of the time, but if they cannot, they may be deposited into various body systems as chronic accumulative poisons. This, in brief is how the body is made and programmed by our Creator. He has designed us this way, and we need to be grateful and respect and honour our Creator for ensuring our safety.
It is the scientists who invented all these chemicals, pesticides, food additives for the food technologists, and all sorts of harsh chemical drugs for the doctors to use who are to blame.
Mother Nature has never prescribed we should live this way.
Toxicity to other animals:
Carbofuran usage has increased in recent years because it is one of the few insecticides effective against soybean aphids. Its usage has expanded since 2002 to include most soybean-growing regions of the U.S. Carbofuran is also known to be highly toxic to birds. In its granular form, a single grain will kill a bird. Birds often eat numerous grains of the pesticide, mistaking them for seeds. Shortly thereafter they die. Before it was banned, granular Carbofuran was blamed for millions of bird deaths per year. The liquid form of the pesticide is less hazardous to birds because they are not as likely to ingest it directly. Nevertheless, it is still very hazardous.
Banned agro-chemicals continue to be used in rice fields:
Kedah is the rice growing State of Malaysia. Some 96,558ha the Muda Agriculture Development Agency (Mada) is used in rice cultivation. This is the largest rice production centre in the country. But many Malaysians may not have a clue as to what goes into the production of this staple grain.
Set up in the late 1960s, Mada was envisioned to be the proverbial rice bowl as part of the socio-economic development plan of Malaysia. Today, it accounts for close to 50% of the country’s rice production of 2.3 million tonnes.
Farmers’ complaints:
In June, Mada will be 39 years old. However, things are not all going well in the rice fields and among the 48,500 farmers who toiled to put rice on our plates. Farmers have suffered floods and droughts in previous years. They blamed this to climate change as well as diminishing soil fertility and pesticide poisoning. Rice farming has never been more difficult. Other problems appear that agro-chemicals misuse, a habit inevitably inculcated by the government subsidy scheme, is proving to be a hard habit to kick. More and more pesticides of different kinds are now being used.
Banned pesticides:
However under the Pesticides Act 1974, 28 insecticides, herbicides and fungicides have been banned. However, the notorious Endosulfan, a highly acute toxin and a suspected endocrine disruptor, which was banned in November 2005 with a one year phase-out period to clear existing stocks, is still widely applied in rice farms.
Marketed under the trade name of Thiodan by Bayer, Endosulfan is heavily relied on by farmers in the Mada scheme to solve all sorts of pest attacks.
However, Endosulfan is banned in more than 50 countries. Due to its high toxicity and high potential for bioaccumulation and environmental contamination, a global ban on the use and manufacture of endosulfan is being considered under the Stockholm Convention. The international agreement to phase out harmful chemicals referred to as Persistent Organic Pollutants (POPs) decided at its meeting last October to list endosulfan as a POP by its next meeting at the end of the year.
Situation in Malaysia
Rice farmers say farmers say they have no choice but to rely on the banned pesticide for its effectiveness. Endosulfan is an organochlorine compound that is used as an insecticide and acaricide. This colourless solid has emerged as a highly controversial agrichemical due to its acute toxicity, potential for bioaccumulation, and role as an endocrine disruptor.
Banned in more than 62 countries, including the European Union, several Asian and West African nations, and soon in the United States, it is still used extensively in many other countries including India, Brazil, and Australia. It is produced by Bayer CropScience, Makhteshim Agan, and Government-of-India–owned Hindustan Insecticides Limited among others. Because of its threats to the environment, a global ban on the use and manufacture of endosulfan is being considered under the Stockholm Convention.
Chemicals-dependent
The dilemma in Malaysia:
However, rice farmers in the Mada scheme openly admit that the prohibited substance Endosulfan is available and constantly sprayed to rid the farms of pests, especially the golden apple snail (siput gondang emas).
Generally referred to as racun Cina (Chinese poison) as the packaging carries only descriptions in Chinese words, farmers say they have no choice but to rely on the banned pesticide for its effectiveness.
From time to time, there have been newspaper reports of farmers complaining of skin rashes and sprayers falling sick after applying the chemicals in the field.
As the Agriculture Department has beefed up enforcement, sellers and buyers have devised ingenious ways to evade detection. For example, farmers would place orders in the shop but pick up the contraband in a rubbish bin at another location.
Another farmer says his problem with pests began after he switched from the traditional transplanting practice to direct seeding 15 years ago. Before Mada intervention, farmers sow rice seeds in a nursery and transplant the saplings to the growing plot later.
Twenty years ago, a farmer said he used buffaloes to plough his farm and he never used pesticides. But now, his farm cannot do without these chemicals, he adds.
His 60 year old neighbor shares his frustrations. The number of pesticides used has increased tremendously. For one relong they spend RM120 for two rounds of herbicide spraying and RM45 for three times of pesticide spraying and that excludes labour costs, he explains.
Fruits and vegetables in Malaysia:
The following are a list of common fruits and vegetables grown in Malaysia. Note that some fruits are either considered botanically as vegetables and vice versa or eaten as vegetables.
The fleshy fruits:
Almost all fruits we know are fleshy. Here are the examples:
Cashew apple (fleshy), Otaheite apple (fleshy), mango (fleshy), custard apple, soursop, durian, pineapple, papaya, melon, watermelon, persimmon, Malay gooseberry, mangosteen, avocado, langsat, duku, breadfruit, jackfruit, banana, guava, water apple, java plum, starfruit or belimbing manis, camias or belimbing asam, coconut, nipa palm fruit or buah atap, salak, sugar palm fruit or kabung, passion fruit, pomegranate, apple, lime, orange, pomelo, dragon eye fruit or mata kucing or longan, lychee, rambutan, sapodilla or ciku,
The leafy-fleshy vegetables:
Some of them are fleshy, but a lot are leafy. Here are the examples:
Banana bud (fleshy), red-streaked bean (fleshy), long, twisted cluster, winged bean (fleshy), bamboo shoots, bean sprouts, celery, flowering mustard, white and mustard cabbages (leafy), capsicum (fleshy), cassava (fleshy), chayote (fleshy), chilli (fleshy), Chinese chives (leafy), chrysanthemum (leafy), corn (fleshy), breadfruit (fleshy), eggplant (fleshy), garlic (fleshy), ginger (fleshy), angled gourd (fleshy), bitter gourd (fleshy), bottle gourd (fleshy), snake gourd (fleshy) winter gourd (fleshy), horseradish tree (bean), jackfruit (fleshy), Chinese kale (leafy), lettuce (leafy), lotus root (fleshy), oyster, shiitake and straw mushrooms (fleshy), okra or lady’s finger (fleshy), spring onion (leafy), papaya (fleshy), snow or sugar pea (fleshy), pumpkin fleshy), giant white radish (fleshy), sayur manis (leafy), shallot (fleshy), soybean (fleshy), Ceylon, Chinese, and English spinach (leafy), sweet potatoes (fleshy), taro or cocoyam (fleshy), water chestnut (fleshy), water convolvulus or kangkong (leafy), watercress (leafy), yam bean or sengkuang, or bengkuan (fleshy)
Guide on decision:
Generally, almost all fruits are more fleshy and sweeter than vegetables, hence they are less likely to contain pesticides except on the outside (skin) where pesticides are sprayed. In contrast, vegetables are generally leafier than fleshy, example cucumber, pumpkin, and various gourds. Hence where vegetables are leafy and thinner, there is more likelihood for larger amounts of pesticides to be deposited over a larger surface areas of the leafy vegetables, and in between the folds of the leaves, example in sawi, bayam, spinaches, cabbage, and lettuce, than in solid vegetables with smaller surface areas like in cocoyam, yam bean and ginger.
How to ensure minimum risk: My recommendation
One of the best approaches is to wash all fruits and vegetables under running water, preferably under warm running water for at least 10 minutes, especially between the foliage where the pesticides may be trapped, examples in between the layers of cabbages. Tear them open under a running tap. This would have removed at least 99.999 % of any water soluble pesticides therein.
Blanching:
If the vegetables are to be eaten straight away, then soak them in a pot of almost boiling water between 96 -98 degrees Celsius for between 30 seconds to 2 minutes. This process in food technology is called ‘blanching’ The very hot water in this process (blanching) will inactivate all the browning enzymes like polyphenol oxidases that cause browning reactions in fruits and vegetables when they are crushed, bruised or cut and also it inacvtivates vitamin C destroying enzymes called ascorbinase or ascorbate oxidase.
Deactivate enzymes and stabilizes vitamins:
This will not only remove all the remaining residual pesticides still present (unlikely), but the destruction of the enzymes by the heat of hot water will also stop the browning reaction, and at the same time, stabilize the amount of vitamin C in them. The vegetables will look fresher and also retain their nutritive values. Please do not boil the vegetables or keep them for over 2 minutes. Longer than that is no longer blanching, but cooking.
Buy time for natural biodegradation in the kitchen:
If the vegetables are not for immediate consumption, do not blanch them, but just wash them throughout under a good flow of running tap water for at least 3 minutes, after which they may be kept in a refrigerator at around 5-10 degrees for another 3-4 days to borrow time for anymore pesticide residues still left (very unlikely) to biodegrade and decompose on their own.
After that, the fruits and vegetables may be taken out and rewash under a tap once more for another 1-2 minutes.
Simple Home Science & Food Technology:
Applying such a home science and simple and cheap food technology in the kitchen would have ensured not a trace of pesticide is left if you follow my advice. If there are still, it would be in the tune of just 1 part in 10 trillion – almost nothing left, maybe a molecule in a swimming pool of water
Better than ‘organic’ foods:
This is far, far better than believing in all those ‘organic fruits and vegetables’ where you waste your money. Organic foods do not mean there is no chemical inside. It is a very long story which may take me another 10 pages to explain, and I am not going to waste my time.
Just trust and have faith in me in what I tell you. Just follow me. Do not believe in all those sales talks by health freaks, and health fanatics.
by:
Research Nutritionist jb lim BSc (Physiol & Chem) PG Dip Nutr MSc (Food QC) MD PhD (Med) FRSPH FRSM
Formerly,
Food & Nutrition Research Toxicologist
Massachussetts Institute of Technology
Researcher in Community Medicine
Instititute for Medical Research
Currently,
Special Medical and Chief Science Adviser &
Head of the Technical Advisory Board
The Dynapaharm Int'l Group
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On Wed, Aug 18, 2010 at 10:48 AM, guat hiong tee wrote:
Dear Dr Lim,
Thank you so much for your lengthy and comprehensive explanation to my query of Furadan and watermelon.
You have taken so much effort to explain the toxicology, pharmacology, physiology, biochemistry, nutrition, current situation of pesticides, herbicides and fungicides usage in Malaysia; and last but not least, the very important home science in handling our fruits and vegetables at home. You made it so simple to understand, I am sure your article will benefit a lot of people. I really enjoy reading and digesting the facts given in the article.
Once again, thank you for your effort and sacrifice for your sleep.
Warm regards,
Helen
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JB Lim Reply to Helen:
Dear Helen,
I am so glad you replied for the time and effort I took to explain to your query. I was actually quite disappointed when you did not initially acknowledge my trouble.
But now having heard from you, I am glad to reciprocate in reply to you in Mandarin Chinese - méishì (its nothing), bùyòngkè (no need to thank, you are welcomed), bu kèqi (no need to be polite).
I am glad you enjoyed my opinion. I have a number of feed back from others too and they too felt the same thing. One girl told me a health company sent some watermelon to a lab for chemical analysis, and the report came back that Furadan was not detected as much as I have argued and explained.
Our Malaysian Food Act 1983, and Food Regulations 1985 do not allow all these pesticides to be present in our foods except in very trace amounts of 1-2 ppm.
The Food Quality Division of MOH and the Dept of Chemistry are closely monitoring all these food additives especially those from China and Cameron Highlands as best as they can.
So I think our foods here are quite safe albeit some may escape detection.
Regards
jb lim
Is the info below true?
Furadan in watermelon! Pictures and warning in attachment.
I would like to hear your comments.
Thank you and regards,
Helen
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JB Lim's reply to
Helen Tee Guat Hiong
Scientist and Colleague
Formerly, Institute for Medical Research
Currently, Public Health Institute
Ministry of Health Malaysia
Dear Helen,
Thank you very much for your enquiry on the presence of Furadan in watermelon. I have received the same e-mail warnings from many other e-mailers like Ms. Annie Lee, Ir. Tai Onn Lau, Dr Ganeshadeva Muthu Ramalingamm and Ms Josephine Wong, among others.
Thank you to all of you who have written to me about the presence of Furadan-laced watermelons.
This story and warning has also appeared in a few websites and blogs. The following are my analysis and critical opinion
It really beats me to understand whoever puts that piece of warning about watermelon being laced with Furadan (Carbofuran) should specifically target watermelon as the only fruit to be cautioned about the presence of this chemicals. Why only watermelon? Why not in papaya, banana, pineapple, star fruit, dragon fruit, pomelo, and so on? Why single out watermelon only? It really beats my understanding. To make it even more unconvincing, at least to a scientific mind, no data as evidence was given. There was not a single report of a chemical analysis done to actually show the amount of Furadan present in the watermelon, let alone compare the data on amount with other fruits and vegetables. What I receive from this chain e-mails is just a bunch of absolute rubbish without any evidence given.
Evidence-based:
Not a single data from chemical analysis was give. It was just claims, claims, and highly unscientific claims to discredit watermelons and the farmers that all. To produce such a claim in a Court of Justice without a single shred of data or evidence, would instantly, not only just thrown out, but the claimant would be asked to pay with cost for damage and compensation to the watermelon producers. All claims must produce data, data and evidences. Don’t just claim by cooking up a story and send them out through chain mails to confuse and deceive the less educated. Not every recipient of chain e-mails are morons, imbecile and idiotic.
Difficult without food analysis report:
But this does not imply that watermelon or any fruits and vegetables are not laced with Furadan if farmers deliberately add them to kill off pests. What I am asking is for people to show proof and evidences. That all I am asking. Even if they spray the crops with Furadan or any pesticides, this does not mean the watermelon, or any other fruits and vegetables harbor them. They must show the data and report of a chemical analysis from a credited and registered laboratory, and the report need to be carried out and signed by a qualified Chemist or a Food Quality Controller whose university degree in Analytical Chemistry must be registrable with the Malaysian Institute of Chemistry under the Chemist Act 1975. Less than that, are all rubbish reports and claims.
Furadan broad spectrum action:
In the best of my understanding, Furadan is a broad spectrum carbamate pesticide that kills insects, mites, and nematodes on contact or after ingestion. It has a potential to cause damage to the reproductive system to all pest, and probably to the health of humans as well by prolonged and chronic exposure. Carbofuran is not alone in the list of pesticides where its widespread use in agriculture that has caused severe environmental pollution and public health risk.
Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) generally called as Furadan is a broad spectrum carbamate compound which has been used against soil and foliar pests of field, fruit, vegetable, and forest crops. So why only on watermelon as the e-mail has portrayed to mislead consumers and the public. Whoever started it must have a grudge against watermelon farmers, probable those in Cameron Highlands. I think they are out to sabotage their livelihood.
Toxicity:
Carbofuran is highly toxic by inhalation and ingestion and moderately toxic by dermal absorption. But this is also true with many other pesticides. So why only specifically target on carbofuran and watermelon? But I really failed to understand why many e-mailers are out only to mislead others by inventing stories to pass them on to others through their chain e-mails. I receive this from a friend and former colleague for my comment.
Most of the pesticides, especially the organophosphate insecticides, work by interfering with the electrochemical mechanism that nerves use to communicate with muscles and with one another. A key chemical in this communication between synapses is neurotransmitter called acetylcholine. .This chemical produced by the body is used to "fire" the neuron, and this in turn contracts a muscle such as the high frequency flapping of the wings of an insect. Acetylcholine is then inhibited by an enzyme called cholinesterase to prevent further contraction so that the insect can rest.
Toxicodynamics of pesticides (mode of action):
These pesticides lock or block the action of cholinesterase so that it can no longer inactivate the acetylcholine. As the acetylcholine builds up, the muscles of the body become over-stimulated, leading to paralysis and death. The insect literally dies of exhaustion. This mode of action of a pesticide, or in some drug action, we called it the ‘key and lock’ theory. That is how they act on insects by preventing cholinesterase from erasing the acetylcholine to exhaust their muscular activity. It is in this way classified as a neurotoxin.
Carbamate insecticides have similar toxic mechanisms to organophosphates, but have a much shorter duration of action and are thus somewhat less toxic. However, other feel that it has the highest acute toxicity to humans of any insecticide widely used on field crops. A quarter teaspoon (1 mL) is said to be fatal. Most carbofuran is applied by commercial applicators using closed systems with engineered controls, so that there is no exposure to the chemical through pouring or measuring. Whatever the level of toxicity, it remains true that all pesticides need to be handled with care, including Furadan.
Paraquat mode of action:
This mode of action of an insecticide (pesticide) s different from that of a Paraquat which is not an insecticide but is a weed-killer. Weeds may also be considered as a plant pest, and in this way it is also a pest to a farmer.
Paraquat inhibits photosynthesis. In light-exposed plants, it transfers electrons to molecular oxygen to form highly destructive reactive free radicals. The oxidized form of paraquat is regenerated to shunt electrons from photo system I to start the cycle again. Another way of putting it, is that it involves diverting the flow of energy captured from sunlight in photosynthesis to produce highly reactive free radicals which destroy cell membranes to quickly desiccate leaves. This happens within hours in bright sunlight because of its high energy levels.
Pesticides may also induce oxidative stress, leading to generation of free radicals and alteration in antioxidants, oxygen free radicals, the scavenging enzyme system, and lipid peroxidation (Banerjee et al. 1999, Etemadi et al. 2002).
In 2002, anti-paraquat campaigners were jubilant when, after a 10-year campaign, they succeeded in persuading the Malaysian government to clamp down on the substance. The government issued a circular that year saying that pesticides containing paraquat and calcium cyanide would not be re-registered and all forms of advertising of the two substances would be banned.
But victory for anti-paraquat campaigners lasted only four years. The government's decision now to ‘‘temporarily lift the ban'' swings the lobbying war in Syngenta's favour. The Swiss agrochemical giant, Syngenta markets this herbicide under the brand name Gramoxone, and other industry groups.
‘‘We want to do an extensive study on paraquat, its harmful effects and positive aspects, before the set date for its total ban in November next year,'' Pesticide Control Division director Nursiah Tajul Arus was quoted as saying. The Pesticides Board is now allowing registration of paraquat for all crops ‘‘to facilitate the study''.
Effect of Carbofuran on neurotransmission:
According to The US Environmental Protection Agency (EPA) carbofuran can over-stimulate the nervous system, causing nausea, dizziness. Since organophosphates bind to acetylcholinesterase and other cholinesterases, this results in disruption of nerve impulses, killing the insect or interfering with its ability to carry on normal functions. Organophosphate insecticides and chemical warfare nerve agents (such as sarin, tabun, soman and VX) work in the same way. Organophosphates have an additive toxic effect to wildlife, so multiple exposures to the chemicals amplify the toxicity. But as with other carbamate compounds, carbofuran’s cholinesterase-inhibiting effect is short term and reversible.
Carbofuran on wildlife:
Carbofuran is highly toxic to fish and birds particularly in granular form. Birds often eat them mistaken them for seeds, or through contaminated drinking water. One granule of carbofuran according to one source is enough to kill a small songbird.
EPA has banned the use of carbofuran on all food crops, not just for watermelon because it poses an real health risk, especially to children. It is marketed under the brand name Furadan This has been under EPA review for years. Its granular form was prohibited in the mid-1990s because it was blamed for killing millions of migratory birds. The agency fought to remove the pesticide from the market in 2006.
However, Furadan's manufacturer, FMC Corp. of Philadelphia, Pennsylvania, has fought the federal action. In March, the company voluntarily scaled back its uses, in hopes of preventing broader restrictions.
Pesticides in Human and Animal Health:
Currently, there are more than 865 recorded pesticides according to the Environmental Protection Agency. However, fewer than half of these pesticides are employed for agriculture in the United States and this is even less in Malaysia. Pesticides are man-made and are regulated by the U.S. Department of Agriculture, and here in Malaysia, our list is also controlled by the Malaysian Pesticide Board. However, the EPA determines how much these pesticides can be deposited on crops as well as how much of the pesticides linger on the foods being bought by consumers. Such study as far as we know is not available in Malaysia.
The toxicity of pesticides, are such that we can expect some health risks as they are intended to kill insects and pests. Some pesticides can be extremely toxic. Pesticides containing nicotine are one example. Pesticides can be harmful not only to intended insects and pests, but also to humans, animals and the environment simply because they are specially formulated to be harmful to all live organisms.
Position of pesticides usage in Malaysia:
Since 2003, the Pesticide Board of Malaysia has either totally banned, or partially banned a list of pesticides in Malaysia. A total ban was imposed on DDT, Chlordane, Heptachlor. Sodium penthachlorohenate, Endosulphan (not allowed for rice), Lindane gamma-BHC (not allowed for cocoa), Methomidophos, and Monocrotophos (not allowed for oil palm), while others such as Aldrin, Diledrin, Endrin, etc were withdrawn by the manufacturers. Endosulphan is an organochlorine, and this is completely banned in most countries, but not totally banned in Malaysia.
Biological control:
However, today, scientists have developed bio-pesticides or biologically-based pesticides and these are becoming more acceptable to the public since they are considered to be safer than the traditional chemical pesticides.
To the best of my knowledge even though Carbofuran (Furadan) was not in the list of banned pesticides in Malaysia, there has also not been any report of Carbofuran being used in the cultivation of water melon in Malaysia even though a number of countries have already banned it. In the United States for instance, this pesticides have been applied also in the cultivation of soy beans, potatoes, and corn (maize), but as far as we know, this practice is now banned.
However one report says that Carbofuran usage has increased in recent years since 2002 in most soybean-growing regions of the U.S. because it is one of the few insecticides effective on soybean aphids. We are unable to verify.
Chemical analysis needed:
Carbofuran is a systemic water soluble insecticide that can enter into the root system This means the plant absorbs it through the roots, and from there distributed to the rest of the rest of the plants mainly the vessels, stems and leaves where the insecticidal concentrations are attained. But this does not mean it has also gone into the fruit. I shall explain this later.
Although it has not been found in fruits that are fleshy such as in water melons so far, this does not mean it cannot happen. The only way to find out for sure is to do a chemical analysis on the fruit concerned. This is the only way. The rest are all guessing, rumors and fairy tales. Just show us the analytical chemical report of pesticides inside the fleshy part of a fruit which is the edible portion, not outside on the skin. Also, we need to know how much is present inside the flesh. That’s all that is needed.
Perhaps this pesticide has been used externally in the cultivation of water melons in Malaysia and elsewhere, but I don’t think we have evidence that water melon itself stores the pesticide after harvest.
Molecular weight and absorption:
Plants normally can only assimilate simple compounds of low molecular weights like carbon dioxide from the air through photosynthesis to manufacture starches and sugars, and water (hydrogen and oxygen) through the root systems, together with major macronutrients in the form of elements like nitrogen through nitrogen-fixation, meaning, conversion of atmospheric nitrogen into nitrates and nitrites, or supplied by decaying matter, nitrogen fixing bacteria, animal waste, or through the agricultural application of purpose made fertilizers, phosphorus and potassium, minor macronutrients - calcium, sulphur and magnesium, and other micronutrients like iron, molybdenum, boron, copper and manganese. All these have to be in its elemental form and not in complex compounds.
Some evidence of organic absorption:
However, there are some studies in the literature that some plants can absorb organic nitrogen, but these have to be in very simple nitrogen organic compounds of very low molecular weights like amino-acids. Using all these simple elements and water in the soil together with carbon dioxide from the air, plants manufacture all the starches, sugars, plant acids, aromatic compounds, carotenes and carotenoids, colours and all other phyto-chemicals we know off. It cannot absorb and utilize complex organic compounds such as high molecular weights pesticides, insecticides, or even fertilizers without breaking them down first into simpler elements usually with the help of soil bacteria. They just cannot pass through. There is a cellular and membrane barrier there in place to prevent undesirable substances, especially high molecular weight substances from passing through.
Systemic absorption are possible if the molecular weights of the pesticides are low, but they may be confined on the roots, stems and leaves, and in between the folds of leaves and vegetable. But so far there has been no known absorption into the fruit themselves.
Fruits and seeds are plant babies:
The watermelon, and literally all fleshy fruits which are considered a ‘baby plant’ with the seeds in there are even harder to pass through. Like all living things the mother plant (inclusive of animals) will protect its babies first. It is just a program Mother Nature has written and designed to ensure the ‘babies’ are well protected from harmful substances.
So this means it is less likely that Carbofuran, organophosphates, or other pesticides, or any other exogenous (external) organic substances not produced by the plant itself can ever get through the plant into the fruit because of a membrane barrier that selectively screened out all substances that should not be part of the fruit by nature. They just cannot get through that’s all. In fact, as far as I know, no fruit has been shown to have pesticide residues. Perhaps almost all the pesticides shown to be present are found to be on the outside of fruits, namely on the skin. These are residues left after even the fruits were sprayed with pesticides.
Accumulative poisons:
Pesticides tend to accumulate in fatty material if they are oil soluble like DDT. Hence fatty meats, fish, and dairy products will have higher pesticide residue than the low-fat products. The wax coating on cucumbers facilitates the retention of the fungicides used on cucumbers. But almost all fruits and vegetables are non-fat. So oil-soluble pesticides just cannot get into their root system of plants of fruits and vegetables since plants absorb water, not oil.
Overall, the consumption of low-fiber, fat-rich and calorie-rich diets, along with the use of alcohol, pose a much, much greater threat to human health than chemical residues on our food.
Fruits and vegetables are known to protect against heart disease and cancer. They are rich in vitamins, minerals, fiber, and health-promoting phytochemicals. However, many fruits and vegetables test positive for pesticide residues, with about one-third of them showing up with multiple residues. Research reveals that prolonged exposure to pesticide residues may increase the risk of various cancers and neurological problems (such as Parkinson's disease), and impair the immune system. It is claimed that they cause:
1. Cancer
2. Fertility problems
3. Brain tumors
4. Childhood leukemia
5. Non-Hodgkin's lymphoma
6. Birth defects
7. Irritation to skin and eyes
8. Hormone or endocrine system problems
Nervous system damage:
But so far I have not come across literature of human studies to substantiate the above claim. It is not easy to do such an experiment on humans to prove these claims. The reasons are too long and technical for me to discuss them here unless readers are medical researchers who understand toxicology, statistics, study designs, epidemiology, etc.
Nutritive values of watermelon:
Watermelon is mainly water at 92.6 percent; low in energy at just 28 kilocalories per 100 gm of the fruit. It also contains 5.50 mg vitamin C, and a good source of potassium at 78 mg. per 100 gm, and a very rich source of carotenes. This makes watermelon one of the most nutritious, health-promoting, and cancer-preventive, especially against prostate cancer fruits available. Its carotenoid content in microgram per 100 gm of watermelon is:
Crypto 457
Lycopene 5301
Gamma-carot 90
Beta-carotene 324
Carotenes 410
Sum carot: 6171
What else do we need?
Moreover, fruits, unlike vegetables are normally very fleshy. The plants do not manufacture fruits out of pesticides. I have already mentioned that plants through photosynthesis manufacture all their starches, sugars, and fleshy parts of the fruit as their food, and all other protective substances such as thousands of high molecular weights antioxidants, and photochemical with the help of just water, and all the essential simple nutrients in the form of elements taken in by the roots.
No complicated organic compounds are used for the manufacture of the fleshy parts of the plants. These pesticides are not part of their natural flesh – the fruits, including watermelon. Fruits and vegetables are made up of 99.999999 % natural biological materials produced absolutely, totally, and completely by the plants only using only water and nutrients from the soil, and carbon dioxide from the air, and energy from the Sun.
Plants are made from pesticides:
Plants inclusive of their roots, stems, flowers, fruits and seeds, and vegetables too are not made from pesticides. If they are present, they are sprayed there by man only, and after sometime, even these will suffer biodegradation leaving only very trace amounts – in parts per million on the outside of the leaves, fruits and vegetables. They normally do not get into the fleshy parts inside the plant unless the pesticides are a systemic poison, and must be water soluble.
Mainly on the surface:
Most of the residues remain outside on the leaves, stems, branches, flowers and fruits, and when they are exposed to the air and wind, light, ultra-violet rays of the Sun, heat, moisture and bacteria, these pesticides rapidly decompose even on the outside surface (skin) of the fruit.
Life span of pesticides:
I do not know the t ½ (t 50) value of Furadan, meaning the time taken for half the amount of Furadan left after decomposition, decay, biodegradation or when ingested. This is called ‘half-life’ meaning 50% of the Furadan left given by the symbol‘t ½’ or‘t 50’. This is a term used especially in pharmacology to determine the half life of a drug inside a body.
Even if Carbofuran is left in the soil, or has been sprayed onto a fruit like watermelon, the half-life will depend on many decomposition factors such as the amount of heat, light and water, their amount and intensity.
It is unlikely they can stay too long even if they are present inside the flashy part of a fruit or plant, as the living plant itself will quickly try to destroy them with their tens of hundreds of antioxidants and other phytochemicals present. These are manufactured by a plant in a plant specially to protect them. The plants too do not need these chemicals inside their body.
Antioxidants in plants:
Plants bear not just leaves, stems, flowers and fruits, but they also manufacture tens of hundreds of different antioxidants to protect themselves from free radicals, especially free oxygen (singlet oxygen) radicals produced by the ultra-violet light of the Sun as they have to remain in the Sun for at least 10 to 12 hours everyday to manufacture food for themselves through photosynthesis.
This is no joke as they have to remain immobile in the Sun especially in the hot tropical Sun for so long everyday. They cannot move into the shade like animals. So Mother Nature programmed into the plants so that they can produce tens of hundreds of different antioxidants of varying molecular weights to protect themselves from free radicals generated by the ultraviolet rays of the Sun. Most of them are very high molecular weights antioxidants of over 30,000. These are all not biologically available to humans and other animals. These antioxidants are manufactured by the plants to protect themselves and are not meant for humans and animals to take away for their own protection.
Low molecular antioxidants:
But these plants in their mercy as Mother Nature prescribes leave only a very small amounts of very low molecular weight antioxidants for humans and other animals. Their molecular weights are less than 30000 such as vitamin C, vitamin B2, carotenes, catechin, polyphenols, flavonoids. Their molecular weights are in the range of 200-400 only. These are bio-available to humans and animals as they can pass through the human intestinal gut even without ‘active transport’ across the intestinal membrane.
But we are getting so few of the huge range of antioxidants and protective phytochemicals the plants produce, maybe just less than 1 % of them. Only these, vitamin C, carotenes, bioflavonoids, etc are given to us out of mercy and kindness of the plants. We literally live on their scrapes and morsels like beggars.
The ‘selfish’ plants:
The rest of the 99.9 % of protective antioxidants the plants keep for themselves because they have to stand out in the hot Sun all day long against UV-ray generated oxygen radicals. We can remain in the shade, and are given just a little vitamin C of low molecular weight which the plants hardly need. That’s how Mother Nature works to prioritizes in order to keep all living creatures and plants alive. God is very fair.
Free radicals are also needed:
Oxygen radicals are fine and good for the body in limited qualities as when required to protect the body against infection against invading bacteria, but in excess these oxygen radicals released by the phagocytes attack not just pathogenic bacteria, but they also attack the body by damaging the cells and the DNA in them The role of the endogenous (produced within the body) radical scavengers (antioxidants) is to remove the excess free radicals from the body.
The body’s antioxidants:
There are 3 endogenous antioxidants produced by the body to combat free radicals in the body. These are: Superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-Px).
Of the 3 endogenous antioxidants, SOD is the most active in removing free radicals from the body, while catalase and GSH-Px have extremely high molecular weights, and they cannot be used for the treatment of disease even by injection. As SOD’s levels rise to fight against pathogenic invasion, this capacity to rise, called ‘induction capacity’ or ‘inducibility’ declines rapidly with age.
Only by injections:
Because SOD, catalase and GSG-Px are of such high molecular weights they just cannot pass through the intestinal gut. So some health companies synthesize these products to be given by injections to bypass the intestine.
My answer to these rubbish products produced by some of these health product companies and sell them as food supplements and even as pharmaceuticals is because these products cannot be retained by the body.
It has been shown that just 6 minutes after an injection of SOD into the body, the body starts to throw half of them out into the urine. These people who believes SOD injection is good for health in combating oxygen and peroxide radicals in the body is completely wasting their money. This is the same as those who take high doses of vitamin C in the erroneous belief that they would be retained in the body for a long time even after the blood has been saturated by them. They think that if a little vitamin does me good, a lot will do me even better? They have been brain-washed by health freaks. A little knowledge is a dangerous thing.
The protective barrier:
The body is so protective against any undesirable substances entering it, that it is far harder for them to enter (be absorbed) than it is for them to be excreted out through the kidneys into the urine. In other words the threshold of the kidney is much lower for expulsion than the much higher threshold of the intestines to absorb.
Most substances, even salts and nutrients have to be chemically pumped through the intestines, a process in physiology we call it as ‘active transport’ such as the ‘sodium pump’
It is a energy-demanding mechanism across a concentration gradient by using chemical energy such as adenosine triphosphate (ATP). In cells accumulating high concentrations of molecules that the cell needs, such as ions, glucose, amino acids they have to be chemically pumped across, or actively transported across a membrane.
Human gut barrier:
The human gut barrier bars the absorption of any high molecular substances over 30000 trying to enter the body. This is just a protective mechanism in place. All complicated organic substances including starches, complex sugars, proteins and fats need to be broken down first before entering the body for security reason. This is like stripping a person naked, and searching his body first before allowing him or her to enter through a narrow gate into a high security area. This is how God plan, architect, and program our body and the bodies of all other creatures to safe guard us on this Planet.
Not easy to get through:
So it is not so easy for toxic substances to get into the blood stream in humans even if there is no such barrier in plants bearing flowers and fruits as Nature’s first filter.
The Carbofuran or any pesticides has to cross two biologically active protective barriers – one in the plant bearing fruits and seeds as their ‘babies’ , and even if these chemicals get through in traces (perhaps in just a few parts per million or even per billion), these pesticides still have to face the human protective intestinal barrier. It is not as easy as that.
The liver detoxifying chemistry:
Even if toxins do squeeze their way into the body, the liver is there to recognize them by destroying them. In the event the liver is unable to do this because of the complexities of its molecules, it will quickly pass it on to the kidney for expulsion.
We will not go into the highly complex biochemistries of how the liver recognizes a toxin, be it Furadan or anything else, but one example will do here. The enzymes secreted by the liver are like (chemical) knives. If a highly complex molecule is presented to it, the liver will study its chemical structure first to see how it can break it down. It will examine where their weak links are.
Simple chemistry:
These normally are the covalent bonds that bind the molecular fragments together as a whole molecular structure. Once it identifies where the chemical knot is, the liver will produce the specific enzymes (the chemical knife) to cut the knot into pieces so as to loosen the entire knot (the complex molecules, toxins, drugs, etc). Once the chemical knot is cut, the whole structure loosens. The toxin / poison will instantly lose its chemical nature and identity and can no longer act as one. Even a single bond has been sliced off, the chemical nature of a substance including a toxin will be lost. It is a matter of the various enzymes of a liver to cut the various chemical knots in a molecule to render it harmless before sending it to the kidney for expulsion.
Simpler molecules:
The complex molecules will become simpler monomers or isomers or other substances so unlike its original polymer (example). They no longer become a chemical threat to the body. The liver then passes on its metabolic waste products to the kidneys to be thrown away.
This is just one simple example how the liver deals with any poison, drug, or any substance that enters the body willfully (as drugs), or unintentionally as accidental ingestion of a toxin through food. There are thousands of highly complex biochemistries going on in the liver to deal with various kinds of toxins, and we are not going into pharmacokinetics, or biochemical toxicology.
The defensive body:
‘I praise thee because I am fearfully and wonderfully made; thy works are wonderful, I know that full well’ (Psalm 139:14). Truly, the body is fearfully and wonderfully made by God to do this job to protect us. The liver together with the kidneys can easily handle toxins and drugs most of the time, but if they cannot, they may be deposited into various body systems as chronic accumulative poisons. This, in brief is how the body is made and programmed by our Creator. He has designed us this way, and we need to be grateful and respect and honour our Creator for ensuring our safety.
It is the scientists who invented all these chemicals, pesticides, food additives for the food technologists, and all sorts of harsh chemical drugs for the doctors to use who are to blame.
Mother Nature has never prescribed we should live this way.
Toxicity to other animals:
Carbofuran usage has increased in recent years because it is one of the few insecticides effective against soybean aphids. Its usage has expanded since 2002 to include most soybean-growing regions of the U.S. Carbofuran is also known to be highly toxic to birds. In its granular form, a single grain will kill a bird. Birds often eat numerous grains of the pesticide, mistaking them for seeds. Shortly thereafter they die. Before it was banned, granular Carbofuran was blamed for millions of bird deaths per year. The liquid form of the pesticide is less hazardous to birds because they are not as likely to ingest it directly. Nevertheless, it is still very hazardous.
Banned agro-chemicals continue to be used in rice fields:
Kedah is the rice growing State of Malaysia. Some 96,558ha the Muda Agriculture Development Agency (Mada) is used in rice cultivation. This is the largest rice production centre in the country. But many Malaysians may not have a clue as to what goes into the production of this staple grain.
Set up in the late 1960s, Mada was envisioned to be the proverbial rice bowl as part of the socio-economic development plan of Malaysia. Today, it accounts for close to 50% of the country’s rice production of 2.3 million tonnes.
Farmers’ complaints:
In June, Mada will be 39 years old. However, things are not all going well in the rice fields and among the 48,500 farmers who toiled to put rice on our plates. Farmers have suffered floods and droughts in previous years. They blamed this to climate change as well as diminishing soil fertility and pesticide poisoning. Rice farming has never been more difficult. Other problems appear that agro-chemicals misuse, a habit inevitably inculcated by the government subsidy scheme, is proving to be a hard habit to kick. More and more pesticides of different kinds are now being used.
Banned pesticides:
However under the Pesticides Act 1974, 28 insecticides, herbicides and fungicides have been banned. However, the notorious Endosulfan, a highly acute toxin and a suspected endocrine disruptor, which was banned in November 2005 with a one year phase-out period to clear existing stocks, is still widely applied in rice farms.
Marketed under the trade name of Thiodan by Bayer, Endosulfan is heavily relied on by farmers in the Mada scheme to solve all sorts of pest attacks.
However, Endosulfan is banned in more than 50 countries. Due to its high toxicity and high potential for bioaccumulation and environmental contamination, a global ban on the use and manufacture of endosulfan is being considered under the Stockholm Convention. The international agreement to phase out harmful chemicals referred to as Persistent Organic Pollutants (POPs) decided at its meeting last October to list endosulfan as a POP by its next meeting at the end of the year.
Situation in Malaysia
Rice farmers say farmers say they have no choice but to rely on the banned pesticide for its effectiveness. Endosulfan is an organochlorine compound that is used as an insecticide and acaricide. This colourless solid has emerged as a highly controversial agrichemical due to its acute toxicity, potential for bioaccumulation, and role as an endocrine disruptor.
Banned in more than 62 countries, including the European Union, several Asian and West African nations, and soon in the United States, it is still used extensively in many other countries including India, Brazil, and Australia. It is produced by Bayer CropScience, Makhteshim Agan, and Government-of-India–owned Hindustan Insecticides Limited among others. Because of its threats to the environment, a global ban on the use and manufacture of endosulfan is being considered under the Stockholm Convention.
Chemicals-dependent
The dilemma in Malaysia:
However, rice farmers in the Mada scheme openly admit that the prohibited substance Endosulfan is available and constantly sprayed to rid the farms of pests, especially the golden apple snail (siput gondang emas).
Generally referred to as racun Cina (Chinese poison) as the packaging carries only descriptions in Chinese words, farmers say they have no choice but to rely on the banned pesticide for its effectiveness.
From time to time, there have been newspaper reports of farmers complaining of skin rashes and sprayers falling sick after applying the chemicals in the field.
As the Agriculture Department has beefed up enforcement, sellers and buyers have devised ingenious ways to evade detection. For example, farmers would place orders in the shop but pick up the contraband in a rubbish bin at another location.
Another farmer says his problem with pests began after he switched from the traditional transplanting practice to direct seeding 15 years ago. Before Mada intervention, farmers sow rice seeds in a nursery and transplant the saplings to the growing plot later.
Twenty years ago, a farmer said he used buffaloes to plough his farm and he never used pesticides. But now, his farm cannot do without these chemicals, he adds.
His 60 year old neighbor shares his frustrations. The number of pesticides used has increased tremendously. For one relong they spend RM120 for two rounds of herbicide spraying and RM45 for three times of pesticide spraying and that excludes labour costs, he explains.
Fruits and vegetables in Malaysia:
The following are a list of common fruits and vegetables grown in Malaysia. Note that some fruits are either considered botanically as vegetables and vice versa or eaten as vegetables.
The fleshy fruits:
Almost all fruits we know are fleshy. Here are the examples:
Cashew apple (fleshy), Otaheite apple (fleshy), mango (fleshy), custard apple, soursop, durian, pineapple, papaya, melon, watermelon, persimmon, Malay gooseberry, mangosteen, avocado, langsat, duku, breadfruit, jackfruit, banana, guava, water apple, java plum, starfruit or belimbing manis, camias or belimbing asam, coconut, nipa palm fruit or buah atap, salak, sugar palm fruit or kabung, passion fruit, pomegranate, apple, lime, orange, pomelo, dragon eye fruit or mata kucing or longan, lychee, rambutan, sapodilla or ciku,
The leafy-fleshy vegetables:
Some of them are fleshy, but a lot are leafy. Here are the examples:
Banana bud (fleshy), red-streaked bean (fleshy), long, twisted cluster, winged bean (fleshy), bamboo shoots, bean sprouts, celery, flowering mustard, white and mustard cabbages (leafy), capsicum (fleshy), cassava (fleshy), chayote (fleshy), chilli (fleshy), Chinese chives (leafy), chrysanthemum (leafy), corn (fleshy), breadfruit (fleshy), eggplant (fleshy), garlic (fleshy), ginger (fleshy), angled gourd (fleshy), bitter gourd (fleshy), bottle gourd (fleshy), snake gourd (fleshy) winter gourd (fleshy), horseradish tree (bean), jackfruit (fleshy), Chinese kale (leafy), lettuce (leafy), lotus root (fleshy), oyster, shiitake and straw mushrooms (fleshy), okra or lady’s finger (fleshy), spring onion (leafy), papaya (fleshy), snow or sugar pea (fleshy), pumpkin fleshy), giant white radish (fleshy), sayur manis (leafy), shallot (fleshy), soybean (fleshy), Ceylon, Chinese, and English spinach (leafy), sweet potatoes (fleshy), taro or cocoyam (fleshy), water chestnut (fleshy), water convolvulus or kangkong (leafy), watercress (leafy), yam bean or sengkuang, or bengkuan (fleshy)
Guide on decision:
Generally, almost all fruits are more fleshy and sweeter than vegetables, hence they are less likely to contain pesticides except on the outside (skin) where pesticides are sprayed. In contrast, vegetables are generally leafier than fleshy, example cucumber, pumpkin, and various gourds. Hence where vegetables are leafy and thinner, there is more likelihood for larger amounts of pesticides to be deposited over a larger surface areas of the leafy vegetables, and in between the folds of the leaves, example in sawi, bayam, spinaches, cabbage, and lettuce, than in solid vegetables with smaller surface areas like in cocoyam, yam bean and ginger.
How to ensure minimum risk: My recommendation
One of the best approaches is to wash all fruits and vegetables under running water, preferably under warm running water for at least 10 minutes, especially between the foliage where the pesticides may be trapped, examples in between the layers of cabbages. Tear them open under a running tap. This would have removed at least 99.999 % of any water soluble pesticides therein.
Blanching:
If the vegetables are to be eaten straight away, then soak them in a pot of almost boiling water between 96 -98 degrees Celsius for between 30 seconds to 2 minutes. This process in food technology is called ‘blanching’ The very hot water in this process (blanching) will inactivate all the browning enzymes like polyphenol oxidases that cause browning reactions in fruits and vegetables when they are crushed, bruised or cut and also it inacvtivates vitamin C destroying enzymes called ascorbinase or ascorbate oxidase.
Deactivate enzymes and stabilizes vitamins:
This will not only remove all the remaining residual pesticides still present (unlikely), but the destruction of the enzymes by the heat of hot water will also stop the browning reaction, and at the same time, stabilize the amount of vitamin C in them. The vegetables will look fresher and also retain their nutritive values. Please do not boil the vegetables or keep them for over 2 minutes. Longer than that is no longer blanching, but cooking.
Buy time for natural biodegradation in the kitchen:
If the vegetables are not for immediate consumption, do not blanch them, but just wash them throughout under a good flow of running tap water for at least 3 minutes, after which they may be kept in a refrigerator at around 5-10 degrees for another 3-4 days to borrow time for anymore pesticide residues still left (very unlikely) to biodegrade and decompose on their own.
After that, the fruits and vegetables may be taken out and rewash under a tap once more for another 1-2 minutes.
Simple Home Science & Food Technology:
Applying such a home science and simple and cheap food technology in the kitchen would have ensured not a trace of pesticide is left if you follow my advice. If there are still, it would be in the tune of just 1 part in 10 trillion – almost nothing left, maybe a molecule in a swimming pool of water
Better than ‘organic’ foods:
This is far, far better than believing in all those ‘organic fruits and vegetables’ where you waste your money. Organic foods do not mean there is no chemical inside. It is a very long story which may take me another 10 pages to explain, and I am not going to waste my time.
Just trust and have faith in me in what I tell you. Just follow me. Do not believe in all those sales talks by health freaks, and health fanatics.
by:
Research Nutritionist jb lim BSc (Physiol & Chem) PG Dip Nutr MSc (Food QC) MD PhD (Med) FRSPH FRSM
Formerly,
Food & Nutrition Research Toxicologist
Massachussetts Institute of Technology
Researcher in Community Medicine
Instititute for Medical Research
Currently,
Special Medical and Chief Science Adviser &
Head of the Technical Advisory Board
The Dynapaharm Int'l Group
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On Wed, Aug 18, 2010 at 10:48 AM, guat hiong tee wrote:
Dear Dr Lim,
Thank you so much for your lengthy and comprehensive explanation to my query of Furadan and watermelon.
You have taken so much effort to explain the toxicology, pharmacology, physiology, biochemistry, nutrition, current situation of pesticides, herbicides and fungicides usage in Malaysia; and last but not least, the very important home science in handling our fruits and vegetables at home. You made it so simple to understand, I am sure your article will benefit a lot of people. I really enjoy reading and digesting the facts given in the article.
Once again, thank you for your effort and sacrifice for your sleep.
Warm regards,
Helen
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JB Lim Reply to Helen:
Dear Helen,
I am so glad you replied for the time and effort I took to explain to your query. I was actually quite disappointed when you did not initially acknowledge my trouble.
But now having heard from you, I am glad to reciprocate in reply to you in Mandarin Chinese - méishì (its nothing), bùyòngkè (no need to thank, you are welcomed), bu kèqi (no need to be polite).
I am glad you enjoyed my opinion. I have a number of feed back from others too and they too felt the same thing. One girl told me a health company sent some watermelon to a lab for chemical analysis, and the report came back that Furadan was not detected as much as I have argued and explained.
Our Malaysian Food Act 1983, and Food Regulations 1985 do not allow all these pesticides to be present in our foods except in very trace amounts of 1-2 ppm.
The Food Quality Division of MOH and the Dept of Chemistry are closely monitoring all these food additives especially those from China and Cameron Highlands as best as they can.
So I think our foods here are quite safe albeit some may escape detection.
Regards
jb lim
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