Pesticide use and the environment.

Pesticides are intended to kill unwanted organisms. Most act by interfering with a variety of biochemical and physiological processes that are common to a wide range of organisms. Besides target pests, weeds and fungi, they also affect wildlife and human health. Some can be lethal, and many can cause illness at sublethal levels. But the risks differ greatly from pesticide to pesticide. Some are acutely toxic but produce no long-term effects, whilst others are of long-term health or environmental concern. Much of the information on these side-effects of pesticides remains contested, and so there is no agreement about how much harm they cause.