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A substance for destroying harmful insects.
DDT was the world"s first pesticide. Based on a chemical discovered at the end of the 19th century, and used against humans in the First World War, it was harnessed for use against insects by a Swiss scientist, Paul Muller, after the Second. It was considered such a breakthrough at the time, that he was awarded the Nobel Prize in 1948.
In Britain, the government was determined that should become self-sufficient in food - this after our experiences during the recently-ended war; the thoughts were that this should never happen again. DDT was welcomed as a salvation.
At the same time another related pesticide was being developed. This was also a military spin-off, but although not actually used against Hitler, was tested against weeds and proved most effective; it was called "4-chloro-2-methylphenoxy-acetic acid" known as MCPA. This went on the market as the hormone weed killer "Methoxone", and farmers were positively encouraged to use it, and after the 1947 Agriculture Act, when subsidies were introduced for farmers, they were guaranteed profits however much they spent on chemicals to kill their weeds. In those days no one seemed to worry about possible side effects.
Years later these became apparent, and we now know that pesticide residues of this type (organochlorines), stay in the land, or are eventually are washed into the sea - remaining dangerous for decades. They also accumulate in the human body! These risks weren"t publicly disclosed until the early 1970"s, when DDT itself was banned in the USA; but it took until 1984 for it to be banned in Britain, and a further five years to ban most related organochlorines. Research has now linked this family of drugs to much increased incidences of breast cancer in countries in which they were used. Dieldrin, a member of the same family, was only banned in Britain in July 2000, and then only following a EU directive.
The chemical industry had in the meantime been working on a new family of pesticides, which we were assured had none of the same problems - these were called "organophoshates", and known for short as OP"s. These are even more powerful than their predecessors, working on the brain of insects who come upon them. We are assured that they don"t linger in the ground after their job has been done, as they are broken-down by the sun and lose their deadly qualities. However, some scientists are convinced that it is only a matter of time when their use will be tied to increased incidences of children"s asthma and Alzheimer"s and Parkinson"s disease (which now attack young people as well as the elderly). Sheep farmers are compelled to use these chemicals for their biennial sheep dips, and it seems certain that the high doses they experience has given many neuropathy - a disease of the nerve endings - leading to muscles becoming weaker and weaker. A report from the British Medical Association concluded that the effects of pesticides on the nervous system are difficult to detect but they have no doubt that they exist and have caused considerable suffering to people who are exposed to them.
Yet another family of pesticides - "the pyrethroids" - has now entered service, and we are yet again assured that this is less toxic to humans, and aren"t stored up in our bodies over a period of time!
It has been hard to ban DDT in some countries, as it harmful effects aren"t immediately apparent, and it"s very effective when used against termites and suchlike; also when it was first launched in the early 1940"s, its price was $1.19 a pound - now it sells for 17 cents a pound, which also helps explain its popularity.
In the mean time, we are being encouraged by the government and some health experts, to eat more fruit. It is estimated tat a normal, non-organic, bowl of fresh fruit salad would contain nearly 50 artificial chemical (possibly including DDT or other organochlorines - if imported from countries outside the EU); it is debatable whether these negate the benefits of eating the fruit in the first place!
A non-organic apple receives an average of 16 pesticide sprays, while a crop of lettuce will receive over 11.
Government figures released for 1999 (the latest available in September 2001) show that pesticide residues were present in 71% of the food samples tested.