Use of bioassay methods to evaluate mutagenicity of ambient air collected near a municipal waste combustor.

An ambient air sampling study was conducted around a municipal waste combustor; a primary goal was to develop procedures and methods to evaluate the emissions of organic mutagens resulting from incomplete combustion of municipal waste. The products of incomplete combustion from incineration include complex mixtures of organics, particularly polycyclic aromatic compounds, which are present after atmospheric dilution and cooling in emissions as semi-volatile or particle bound organic compounds. Combustion emissions are generally recognized as a potential cancer risk since they contain many carcinogenic and mutagenic polycyclic aromatic hydrocarbons. Analyzing such a complex mixture for the presence of even a few selected chemicals is difficult and provides risk information on only a fraction of the chemicals present. Bioassay methods, however, may be directly applied to evaluate the mutagenic and potential carcinogenic activity of the complex organics from combustion emissions. The Salmonella (Ames) assay was used to determine the mutagenicity associated with particles from ambient air collected near a municipal waste combustor. Dose-response data was generated, and mutagenicity concentrations were calculated to demonstrate the utility of bioassay in assessing the potential impact of emissions from municipal waste combustion. This phase of study quantified mutagenicity concentrations in ambient air but did not detect organic mutagens that could be attributed to incinerator emissions.