OCCURRENCE AND DISTRIBUTION OF NONYLPHENOL POLYETHOXYLATES AND 4-NONYLPHENOL IN NORTHEAST KANSAS WWTPS

Municipal wastewater treatment plants are potential sources of a variety of hormonemimicking chemicals discharged into surface waters. Nonylphenol polyethoxylates (NPnEOs), surfactants in domestic and industrial cleaning detergents, are often discharged into sewers that transport these chemicals to wastewater treatment facilities. These chemicals are biologically transformed into nonylphenol mono- or di-ethoxylates and nonylphenols during conventional aerobic wastewater treatment. Research has shown that these metabolites constitute a class of endocrine disruptors that are estrogenic to fish, birds, and mammals. We investigated the occurrence and distribution of NPnEOs and their derivatives in three municipal wastewater treatment plants (WWTPs) located in northeast Kansas. It was found that one of the treatment plants received large amounts of NPnEOs in its raw wastewater. Most of the influent NPnEOs appeared to have been converted to 4-nonylphenol (4-NP), which remained associated with the biomass. The effluent contained low concentrations of 4-NP and NPnEOs with n = 1 to 5.