Many insects are pests. They eat many of the food plants farmers
grow and, not surprisingly, farmers try many tricks to stop the insects.
are the latest human invention for killing pest insects (the '-icide' bit of 'pesticide'
means 'killer'). Pesticides are poisonous chemicals which farmers spray on their
crops. The poison kills the insects.
End of problem. Well not quite. The pesticides don't
just disappear. They stick around and poison many other creatures (including humans
- are thought to die every year because of pesticides poisonings).
Untold
numbers of innocent animals die too, but no-one bothers about them. Pesticides
also pollute water supplies and plants that have been sprayed with them often
contain small amounts when people eat them. People who believe genetic engineering
(GE) is a good idea claim that if farmers use GE plants, they will need less pesticide
which will be better for everyone. Yet pesticide production keeps going up - despite
the large-scale use of GE crops in countries like the USA, Canada and Argentina
which should reverse this trend. Odd that.
Things to think about
- farmers may need to douse their fields with yet more pesticides to get the best out of GE plants. [1]
- world pesticide sales increased in 1996 to $31 billion, up 3.6% on 1995 [2]
- some pesticides resist breakdown for many years and can leapfrog around the globe in the wind. These are the notorious POPs, persistent organic pollutants, and include dioxins, PCBs, DDT, toxaphene and chlordane [3]
[1] New Scientist, 18/12/99, 5
[2] The Gene Exchange, Union of Concerned Scientists, Fall 1997, 13
[3] Science News, 16/3/96, 174-175