Sunday, August 29, 2010

Part 2: Poison in Food (Chemicals and Pathogen)

DDT (from its trivial name, dichlorodiphenyltrichloroethane)
is one of the most well-known synthetic pesticides.


Dr Abe V Rotor

The other kind of food poisons is man-made or man-induced. The most prevalent is farm chemicals. Modern pesticides are designed to cope up with the increasing resistance of insects and pathogens. As a result their residues on food and in the environment have likewise increased tremendously. This is even worst in the case of systemic pesticides that penetrate into the innermost part of the plant as they are absorbed and carried throughout the plant's body via its sap. Any insect that feeds on the sap is killed. This property is also present in some phosphatic pesticides and chlorinated hydrocarbons.

Among the first chlorinated hydrocarbon is DDT that was introduced in the forties as the final answer to the malaria problem, controlling mosquitoes, which spread the disease. It is true that DDT is highly effective not only against mosquitoes but other insects as well that its inventor received the Nobel Prize. It was however, discovered years later that it has a residue that is both persistent and cumulative, and transferred through the food chain. Thus, from the mosquito, the DDT is passed on to the fish, to animals that feed on the fish, and ultimately to man. In spite of the fact that it has long been banned there are still traces of DDT residues found in many places, showing either its persistence, or its illegal manufacture and distribution.

Food Poisoning

There was a case of cheese dog poisoning in Rizal. Scores of children, teenagers and adults attending a party were rushed to the nearest clinics and hospitals. Fortunately all of the victims fully recovered.

Cases of typhoid, hepatitis and gastrointestinal diseases have been on the rise because of unsafe water. In Tokyo and nearby cities Escherichia coli, a common gastrointestinal pathogen spread into an epidemic level. It was controlled after banning the suspected source - hamburger.

There is always a cardinal rule in observing food safety, and that is sanitation. Cleanliness speaks of an establishment's image, and has become an important basis in issuing government permits in the operation of food manufacturing plants, hotels and restaurants.

But how clean is clean? The scientist Lister discovered the principle of aseptic cleanliness. Listerine, a mouthwash brand was named after him. Florence Nightingale, the founder of the nursing profession applied Lister's principle in hospital management. But we often exaggerate cleanliness. We use a variety of cleaning agents such as detergents, pesticides, deodorants, air fresheners, and cosmetics.

My father used to warn us in the family, "We are unwittingly introducing into our bodies materials which may be more harmful than the germs we are trying to control." Rub-on mosquito repellant is carcinogenic.

So with Chlorine, which is added to drinking water and swimming pool. Greenpeace, a vocal environment vanguard organization once raised a "Chlorine Kills" campaign against the excessive use of the chemical. Sodium fluoride mistaken for baking powder or wheat flour is extremely harmful, yet fluoride used in small amount in toothpaste helps keep our teeth strong and healthy.

I remember a story of a boy whose anemic condition had for so long remained a puzzle, until one morning his doctor dropped by, and while having coffee with the family, exclaimed, "Why, I know now why your son is sick!" He observed that the gold lining of the coffee cup was being worn out. The boy, or whoever was using the cup, was slowly being poisoned. The fine gold rim was actually painted with lead as paint medium.

How many of our utensils at home contain harmful metals? Do not cook food with vinegar in aluminum pots. Do not use Antimony- or Cadmium-plated utensils. Remember that plastic containers react with food, specially the acidic ones. The microwave oven is not as safe as the conventional oven. There are scientists who believe that microwave triggers radiation, which may be harmful to the body in the long run. In spite of this warning the use of microwave, because of its convenience, has increased.


NOTE: DDT was first synthesized in 1874, DDT's insecticidal properties were not discovered until 1939, and it was used with great success in the second half of World War II to control malaria and typhus among civilians and troops. The Swiss chemist Paul Hermann Müller was awarded the Nobel Prize in Physiology or Medicine in 1948 "for his discovery of the high efficiency of DDT as a contact poison against several arthropods." After the war, DDT was used as an agricultural insecticide, and soon its production and use skyrocketed.

In 1962, American biologist Rachel Carson wrote Silent Spring. The book cataloged the environmental impacts of indiscriminate DDT use in the US and questioned the logic of releasing large amounts of chemicals into the environment without fully understanding their effects on the environment or human health. The book suggested that DDT and other pesticides cause cancer and that their agricultural use was a threat to wildlife, particularly birds. Its publication was a signature event in the birth of the environmental movement. It produced a large public outcry that led to a 1972 ban in the US. DDT was subsequently banned for agricultural use worldwide under the Stockholm Convention, but limited, controversial use in disease vector control continues.

Along with the Endangered Species Act, the US DDT ban is cited by scientists as a major factor in the comeback of the bald eagle, the national bird of the United States, from near-extinction in the contiguous US. (Wikipedia)

Continued...

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