Pesticides And The Environment

butterfly
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A major problem with pesticides is that their continued and widespread use causes resistance to build up in the pest population. This results in more broad spectrum pesticides being used. The results in an imbalance of the natural ecosystem as the pests and their natural predators are killed.
DDT breakdown products have caused bird eggshells to thin. This causes breeding failures in birds of prey as eggs are not strong enough to allow the embryo to develop to full term.
Methyl bromide is a soil fumigant that is especially harmful to wildlife. It is reported to be dangerous to game, wild birds, animals, bees and fish. It is also suspected as an ozone depleter.

Pesticides may leach into the water and contaminate water reserves such as rivers. This can have disastrous consequences to the inhabitants of these habitats.