Even with all their advantages, chemical pesticides pose a very serious threat to our planets due to the over-use of them. Their biggest advantage, the ability to exterminate everything where they are uses, is their greatest drawback too. Useful micro organisms and natural enemies are also eliminated in the area of their application, which in turn affect impact adversely on ecological balance. This forces recurring usage of these chemicals.



However, many pest killing compounds have come out which does not kill the pest outright, but suppress their growth and removes them slowly. The semiochemicals disrupt normal behavioral patterns of a pest, resulting in their eventual destruction. Allelochemicals are mixed with toxicants to attract pests to their doom. Insects like fruit flies are killed in this way. These substances are applied on a sticky trap or sprayed on fruit crops after mixing them up with chemical insecticides.

Sex pheromones are among the most potent chemical attractants which can trap sexually active adult pests and destroy them, thereby greatly reducing their reproduction. These pheromones can even disrupt mating habits in them. Application of them in an insect's living environment can eventually make them lose interest in sexual activity. This kind of pest suppression is known as the air permeation technique or inundation. Fruit and vegetable pests are best removed this way.

Feeding deterrents disrupt the normal feeding patterns of pests. Fly repellents used in cattle rearing, and compounds such as dimethyl phthalate used for protecting human body from ticks and mites are good examples. Moth balls can kill a vast variety of pests that feeds on stored articles like books and clothes. Wood preservatives deter termites and wood borers.