Intensifying agricultural practices, lead to high input of pesticides and spread of their residue contamination over catchments raising concern over the health hazard posed by the presence of pesticide residues in the environment. This study aim at providing a basis for monitoring pesticides residue contamination of the water bodies in Lake Naivasha catchment through; identifying the pesticides applied in the catchment, the status of selected pesticides and their potential effect to human health and life of aquatic organisms. The study found that 59%of the pesticides applied within the L....