In recent years, many anthropogenic chemicals occurring in the environment have been shown to mimic the action of endogenous hormones. These endocrine-disrupting chemicals (EDCs) can potentially lead to a host of adverse effects on wildlife, such as the feminization of fish, the lack of reproductive success of some species, birth defects, and the development of physical abnormality. In an attempt to establish the levels of contamination by EDCs in municipal sewage and sludge, we have collected samples in the Toronto area and analyzed them for alkylphenols, alkylphenol ethoxylates and carboxylates, 17ß-estradiol and its metabolites, testosterone, bisphenol A, as well as butyltin species. Previously developed methods using solvent extraction, solid-phase extraction, supercritical fluid extraction, GC/MS, and HPLC determination have been used for such samples. Levels of these chemicals varied from <1 ng/L for 17ß-estradiol in the effluent to nearly 900 µg/L for nonylphenol ethoxylates in the influent. Levels of EDCs in sludge also varied widely from >500 µg/g for nonylphenol to <0.1 µg/g for bisphenol A. The screening of many of the above EDCs has become an integral part of an on-going wastewater quality monitoring program in Toronto.

The occurrence of endocrine-disrupting chemicals (EDCs) such as bisphenol A (BPA), 4-tert-octylphenol (OP), nonylphenol (NP) and its ethoxylates (NPEO) in wastewater generated in the Toronto area has been studied. In all, 97 samples from 40 facilities in ten different industry classes have been collected and analyzed. Widely divergent concentrations have been observed in these samples. They ranged from <0.01 to 195 µg/L for OP, from <0.1 to 253 µg/L for NP, from <2 to 117,570 µg/L for NPEO, and from <0.01 to 149 µg/L for BPA. The results show that the concentrations of NP and NPEO in these samples generally exceeded City of Toronto By-law (No. 457-2000) limits. The results also suggest that detergents based on NPEO are still extensively used by the commercial laundries, and also by the textile products and clothing industries. These facilities, together with several sources in the chemical and chemical products industries and the fabricated metal products industries are believed to be the major sources of NP and NPEO input into the sewer system in Toronto. In addition to the two facilities in the chemicals and chemical products sector, several commercial laundries also had significant on-site releases of BPA. Except for those collected from three facilities in the chemicals and chemical products industries, the levels of OP in these samples were generally low. Many industries in the Toronto area would have to take drastic actions to reduce releases of NPEO and NP if full compliance with the most recent City By-law regarding wastewater quality were to be achieved.