Mutagenicity of the extract recovered from airborne particles outside and inside a home with an unvented kerosene heater

Abstract

Samples collected over a one month period outside and inside a home without a smoker, but with an unvented heater, in a suburban residential area in winter, were examined for mutagenicity with Ames' Salmonella typhimurium assay system. The extracts recovered with Soxhlet extractor and benzene-ethanol (4:1) exhibited mutagenic activity towards both TA 100 and TA 98 without metabolic activation and showed linear dose-response relationship up to the dose, 300μg plate −1. Addition of microsomal enzymes, however, reduced this activity to a considerable extent. Although there was little difference of mutagenic activity between TA 100 and TA 98 for both indoor and outdoor sample, much stronger mutagenic activity (2–3 fold) was found in the indoor sample than in the outdoor sample towards both TA 100 and TA 98. The present results suggest that such increase in mutagenic activity may be attributed to substances derived from the kerosene heater and the inhabitants' living activity other than smoking.