Pesticides
Pesticides is the descriptor applied to chemicals used to kill pests and minimise their impact on agriculture, health and other human interests. Pesticides are often classified according to the organisms which they are used to control, eg as fungicides, herbicides, insecticides, molluscicides, nematicides, rodenticides etc. Since the substances are intended to combat pests they are toxic, and thus not necessarily only toxic to the target but also to non-target organisms and plants.
The problem is that pesticides can magnify in the environment and not easily broken down by naturally occurring bacteria. The ambition is to substitute harmful pesticides with chemicals that exist in nature and have the same pesticidal effects, but not the drawbacks, or with less harmful pesticides.