This report reviews the occurrence and distribution of manmade organic compounds in the surface waters of the United States. On the basis of their aqueous solubilities, nonionic organic compounds partition themselves between water, dissolved organic matter, particulate organic matter, and the lipid reservoirs of aquatic organisms. Ionized organic compounds can be absorbed to sediments, thereby reducing their aqueous concentrations. Transformation processes of photolysis, hydrolysis, biodegradation, and volatilization can attenuate organic compounds, and attenuation rate commonly follow a first-order kinetic process.
Eight groups of manmade organic compounds are discussed:
1. Polychlorinated biphenyls and organochlorine insecticides,
2. Carbamate and organophosphorus insecticides,
3. Herbicides,
4. Phenols,
5. Halogenated aliphatic and monocyclic aromatic hydrocarbons,
6. Phthalate esters,
7. Polychlorinated dibenzo-p-dioxins, and
8. Polycyclic aromatic hydrocarbons.
For each compound group, data pertaining to use, production, and properties are presented and discussed. Processes that influence that the environmental fate of each group, as determined primarily through laboratory studies, are reviewed, and important fate processes are identified. Environmental concentrations of compounds from each group in water, biota, and sediment are given to demonstrate representative values for comparison to concentrations determined during ongoing research. Finally, where sufficient data exist, regional and temporal contamination trends in the United States are discussed.
