Organic Contaminants in Urban Lake Sediments: A Preliminary Assessment

Abstract

Bottom sediments from several urban lakes located in the Phoenix metropolitan area were collected and analyzed for organic priority pollutants. The lakes selected for analysis were broadly representative of the diversity of lake characteristics found in the Phoenix area. That is, lakes were sampled that had different types of primary water sources and that were located in watersheds of differing degrees of urbanization. Preliminary results indicate that only nine of the 114 listed organic priority pollutants were found in measurable quantities in the sediments of the lakes surveyed. The pollutants detected were either phthalate esters or volatile or semi-volatile halogenated compounds. None of the pollutants were common to all the lakes sampled. Dibutyl phthalate was detected in three of the six lakes. A larger database is being developed and will be necessary to determine whether a statistical correlation exists between watershed characteristics and feedwater, and organic composition of lake sediments.