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Pesticides Reduction
Pesticides, unlike some synthetic chemicals, are deliberately introduced into the environment, especially in the context of modern intensive farming. They include herbicides, insecticides, and fungicides. Their use is on the increase, and they represent a serious threat to sustainable agriculture and biodiversity.
Then there is the rapidly worsening problem of resistance. Pests develop immunity to specific substances. New pesticides are invented to combat this, and in a vicious circle resistance increases in line with them. The newer organophosphate insecticides are a case in point. These are fast-degrading, but so poisonous and unselective that they encourage resistance while destroying the insects' natural predators. Use of pesticides is increasing and continues to inflict terrible damage. Seals in coastal areas have been found to have severely depressed immune systems. Around the North American Great Lakes, the drainage area for a vast agricultural region, bald eagles, lake trout, mink, and snapping turtles are among species exhibiting reproductive and endocrine problems. Although it is impossible to single out any one cause, there are signs that beluga whales in the heavily polluted St Lawrence estuary in Canada may be reproducing at less than a third of the rate of Arctic belugas, and there are instances of hermaphroditism.
Any threat to the world's biodiversity threatens us too. This
is partly because we depend on a large number of species for the
manufacture of medical drugs and other consumptive uses. Less
directly, but more significantly, it is because what happens to
other species could also happen to us. Nobody invents a pesticide
compound with the intention of doing away with songbirds or whales.
But we need to remember that pesticides are, by definition, toxic.
They are designed to kill. |