INDOOR AIR SAMPLING AND MUTAGENICITY STUDIES OF EMISSIONS FROM UNVENTED COAL COMBUSTION

To develop sampling strategies and bioassay protocols for indoor air containing emissions from coal combustion in homes of the rural Xuan Wei County in China, we developed a medium-volume sampler to collect the less than 10- mu m particles and semivolatile organics by a filter and an XAD-2 resin, respectively. A high-volume particulate sampler was used for comparison. The coal was burned under conditions that simulated the open-pit combustion that occurs in Xuan Wei. High-volume and medium-volume sampling yield similar, high particulate concentrations of 38-39 mg/m**3. Fifteen percent of the total extractable organic mass was collected in the XAD-2 resin, and the remaining 85% was retained in the filter. The polycyclic aromatic hydrocarbons found in the XAD were composed of four or fewer rings. In the Ames Salmonella assay, the XAD sample showed low mutagenic activity, and most of the mutagenic activity was found in the filter. The coal combustion emitted both direct- and indirect-acting mutagens, most of which were frameshift mutagens.