Chemical fate and transport in the environment

Abstract

Advection and dispersion are both important transport processes that move pesticides and toxic chemicals from place to place. Because adsorption of these chemicals is so important, especially for the more hydrophobic chemicals (log Kow>2), we must understand sediment transport of adsorbed species as well as water transport of dissolved species. Transport includes input to the water body from the atmosphere, and dry deposition and wet precipitation are additional sources of these chemicals. Chemicals can undergo many physical (sedimentation, adsorption, desorption, volatilization), chemical (hydrolysis, oxidation, photolysis), and biological (biotransformation) reactions. Perhaps biological reactions are the most common in the environment and the least understood. Transformation products of pesticides and chemicals in the environment are occasionally more toxic than the parent compound, and metabolite research wil be very important in the 1990s. -from Author