Life-Cycle Assessment of Neonicotinoid Pesticides

Insecticides are a class of pesticides used to kill, harm, or repel different species of insects. They act in different ways in organisms based on their active ingredients. For instance, corn plantations commonly use insecticides that have organophosphates and carbamate as the active ingredient, which acts on the enzyme acetylcholinesterase within an insect nervous system. In many cases, these standard insecticide products are being phased out for a new class of insecticide known as neonicotinoids, which use nicotine as the active ingredient. Neonicotinoid compounds interact withnicotinic acetylcholine receptors (nAChR) of the central nervous systems ofinsects. Nicotine acts in an insect’s system in the same way that it acts in the human body. However, neonicotinoids are more toxic for invertebrates than they are to mammals, birds and other higher organisms.

Neonicotinoids became popular because of their high water solubility, which makes their soil application travel through the entire plant. Nowadays, neonicotinoids are one of the most widely used class of insecticides for controlling sucking insects and soil insects. In 2004, the worldwide annual usage of neonicotinoids was approximately 11-15% of the total insecticides in the market. Differentgenerations of neonicotinoids have been created over time. They have the sameprinciple of action in the nervous system; however, the specific active ingredients are different. The first generation of this pesticide class used was 1-(6-chloro-1,3-thiazol- 5-ylmethyl)-1,3,5-oxadiazinan-4-ylidenene(nitro)amine, known as Imidacloprid. It was first registered for use in the United States by the United States Environmental Protection Agency in 1994.