ABSTRACT
The US Environmental Protection Agency (EPA) prescribes test guidelines for chemicals subject to environmental effects test regulations under the Toxic Substances Control Act (TSCA). The tests include acute and chronic toxicity tests using freshwater algae, aquatic plants, daphnids, fish, oysters, and shrimp and fish bioconcentration tests. EPA-designated species were used in most of the studies. The toxicity of Alkylphenol Ethoxylates and some of their metabolites have been evaluated for a variety of species under a wide range of conditions. The results suggest that concentrations of APE and their metabolites, such as nonylphenol, in US river waters and sediments do not approach acutely toxic levels. When toxicity tests were conducted over a period of time under static conditions, toxicity decreased slightly with increasing time, presumably due to the gradual biodegradation of the surfactant. Many nonionic surfactants interact with proteins, changing the shape and activity of enzymatic proteins and solubilizing structural proteins which results in changes in cell permeability.
