Mutagenicity studies of ambient airborne particles. I. Comparison of solvent systems

Organic materials were extracted from airborne particles by shaking with different solvent systems including acetone, benzene, cyclohexane, dichloromethane (DCM), methanol, a mixture of acetone and DCM and a combination of benzene, cyclohexane and methanol. The solvent-extracted materials were tested for mutagenic activity with the Ames Salmonella/microsomal assay system. Acetone- and cyclohexane-extracted materials gave the highest and lowest mutagenic activities, respectively. Re-extraction experiments confirmed that most of the mutagenic material from air particles cannot be extracted by cyclohexane. The sequential extraction with acetone followed by DCM gave a better mutagenic response than acetone alone or acetone in combination with DCM. Extraction with varying amounts of solvent indicated that 1 ml of acetone per mg of airborne particles reached the maximum recovery of mutagenic material.