Seasonal Variation of the Mutagenic Activity of Airborne Particulate Matter in the City of Cold District

Abstract

The seasonal variation of mutagenic activity of air at residential site in Sapporo City was studied over a two year period. Particulate matter was collected on tissue quartz filters for 5 days per month with the standard high-volume air sampler. The mutagenic activity of extracts was tested by the Ames Salmonella assay with and without liver S 9 fraction. The monthly average of the mutagenicity varied between 5.2 and 48.2 revertants/m³ of air for TA 98 and between 2.4 and 44.5 revertants/m3 of air for TA 100 with and without liver S 9 fraction. The increasing order of mutagenic activity per cubic meter of air was clear (summer <spring <autumn <winter). The mutagenicity was 4-6 times as high for the winter period as for the summer period. The monthly variation of mutage nicity showed a pattern similar to those of PAH, 1-NP concentration and kerosene consumption for space heating. The mutagenicity was strongly correlated with PAH and 1-NP concentration. The mutagenicity was negatively correlated with the temperature below 10°C but not correlated between 15°C and 20°C. BaP accounted for 0.3-2.0% and 0.7-4.5 % of the indirect acting mutag enicity of the whole extracts with TA 98 and TA 100, respectively.