||Health Effects Research Lab., Research Triangle Park, NC. Genetic Bioassay Branch. ;Environmental Health Research and Testing, Inc., Durham, NC. ;Battelle Columbus Div., OH. ;Acurex Corp., Research Triangle Park, NC.
The incineration of the pesticide dinoseb with staged combustion and reburning reduced not only the NOX by 96% compared to the absence of these two control technologies, but also the mutagenic potency of the emissions were reduced by 60% and the mutagenic emission factor by 60% compared to that of staged combustion alone. Although chemical analysis for a variety of nitroaromatics indicated the presence of only a few such compounds at appreciable levels, mutagenicity bioassays suggested that 70-90% of the mutagenic activity of the dichloromethane-extractable organics in the emissions may be due to nitroaromatics. Therefore, optimization of combustion conditions to reduce NOX emissions from fuels high in nitrogen, although desirable in itself, may lead to the formation of as-yet unidentified nitrated species. Thus, staged combustion and reburning appear to be effective technologies for reducing NOX and minimizing the mutagenic activity of the emissions resulting from the incineration of a nitrogen-containing hazardous waste. This study also illustrates the value of performing both chemical and biological analyses of chemically complex mixtures, such as incinerator emissions, in order to characterize the potential health effects of such mixtures.