p1- Overview.p p2- Sample preparation approaches and methods to detected and quantify different classes of compounds, as well as approaches for iin vivoi and iin vitroi toxicity evaluation.p pThe classes of pesticides will be as follows.p p -Insecticides, such as organochlorines, organophosphates and carbamates. This category also includes insect repellents such as citronella of natural origin and diethyltoluamide DEET, and others. p p-Herbicides or weed killers e.g. paraquat, diquat and glyphosate, and others. p p-Fungicides when applied to wood, these are called wood preservatives.p p-Rodenticides. p -Fumigants, meaning those compounds that exist either as a gas or a vapor at room temperature and may be used as insecticides, fungicides or rodenticides, especially in closed storage places. They are extremely harmful due to their physical properties, rapid environmental dissemination and human or animal absorption examples include aluminum phosphate, cyanide and methyl bromide. pp p-Ot