ABSTRACT

The use of pesticides is important and essential to protect and facilitate agricultural productivity, since pests are largely responsible for losses incurred during the production of food. Pests can be insects, mice, fungi, microorganisms, and undesirable plants (van der Hoff and van Zoonen 1999). Classifi cation of pesticides can be made according to the Environmental Protection Agency (EPA) regarding the type of pest targeted (e.g., insecticides, fungicides, algaecide, herbicides, and nematicides) but they can also be classifi ed regarding their chemical properties namely organophosphate, organochlorine, carbamate, and pyrethroid pesticides. The World Health Organization (WHO) recommended the classifi cation of pesticides by hazard, that distinguishes between the more and the less hazardous forms of each pesticide, being based on the toxicity of the compound. Pyrethroid pesticides are synthetic insecticides derived from pyrethrins, natural compounds present in the pyrethrum extract from Tanacetum cinerariae folium (Kaneko 2010). The main active constituents of the extract are pyrethrin I and pyrethrin II with smaller amounts of the related cinerins and jasmolins. As can be seen in Fig. 1, the structural difference between the pyrethrum extract constituents is that pyrethrin I, cinerin I, and jasmolin I have a monocarboxylic acid (ester of chrysanthemic acid) while pyrethrin II, cinerin II, and jasmolin II have a dicarboxylic acid (ester of pyrethric acid) (Gosselin et al. 1984; Wakeling et al. 2012).