ABSTRACT
This chapter concerns the insects and weeds, as indicated by the inclusion of the organochlorine, organophosphorous and carbamate pesticides and the phenoxyalkanoic acid, urea, and triazine herbicides. It provides an idea of the environmental concerns of the some classes of pesticides mentioned. Pesticide reactions of aquatic environmental interest can be divided into two broad types–abiotic and biological. Pesticides have been detected in aquatic ecosystems remote from recognizable sources. Pesticides enter the water from various sources. W. M. Edwards, reports major sources to include: runoff from agricultural lands; direct entry from spray operations; industrial effluents; sewage effluents; spraying of cattle; and dust and rainfall. In general, waters contain pesticide concentrations reflecting regional and local usage. The sediment component of aquatic ecosystems can be an ultimate sink of pesticides; suspended particulates entering slower moving waters such as larger water bodies settle out, and their associated pesticides are added to the existing sediment component.
