23-79) recorded most of the earlier insecticide uses in his Natural History. Historians have traced the use of pesticides to the time of Homer around 1000 B.C., but the earliest records of insecticides pertain to the burning of "brimstone" (sulfur) as a fumigant. Today, such approaches would be classed as repellents, a category of insecticides.
Chemistry project on insecticides and pesticides skin#
We can guess that among the first approaches used by our primitive ancestors to reduce insect annoyance was hugging smoky fires or spreading mud and dust over their skin to repel biting and tickling insects, a practice resembling the habits of elephants, swine, and water buffalo. Humanoids have been on earth for more than 3 million years, while insects have existed for at least 250 million years. Some 10,000 species of the more than 1 million species of insects are crop-eating, and of these, approximately 700 species worldwide cause most of the insect damage to man’s crops, in the field and in storage. Though by no means exhaustive, we will touch on major classes and technologies whether decades old or recently revealed. The purpose of this brief chapter is to provide a handshake overview of what insecticides are, and a short background and a review of the major insecticide classes that have been or are used today to cope with insect pests. The science of biotechnology has, in recent years, even incorporated bacterial genes coding for insecticidal proteins into various crop plants that deal death to unsuspecting pests that feed on them. Insecticides may be natural or manmade and are applied to target pests in a myriad of formulations and delivery systems (sprays, baits, slow-release diffusion, etc.). Control may result from killing the insect or otherwise preventing it from engaging in behaviors deemed destructive. Insecticides are agents of chemical or biological origin that control insects.
Structural formulae shown in this chapter are reproduced with permission from Alan Wood's Compendium of Pesticide Common Names. (2004), Published by MeisterPro Information Resources, A division of Meister Media Worldwide, Willoughby, Ohio Extracted from The Pesticide Book, 6 th ed*.
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