Application of polyurethane foam for sampling volatile mutagens from ambient air

This paper reports the use of polyurethane foam (PUF) in the sampling of airborne mutagens too volatile to be retained by glass fibre filters. Air was sampled simultaneously with a glass fibre filter and PUF plugs, and the two extracts of the samples were tested for mutagenicity and analysed for polycyclic aromatic hydrocarbons (PAH). As PUF itself was found to contain mutagens, it was thoroughly rinsed, and a blank extract of the same PUF used for sampling was tested as a control. The resulting blank extracts were not mutagenic. In the first series of experiments, in which methanol was used as the extraction solvent, sampling induced clear-cut mutagenic effects in the PUF extracts. As the mutagenicity of the PUF itself appeared only with the use of methanol or other alcohols as extraction solvents, a second series of experiments was carried out in which acetone was used as the extraction solvent. In these experiments sampling induced no mutagenicity in the extracts. The discrepancy between the two series of experiments may be due to the absence of volatile mutagens in the second series, but another explanation may be an artefact induced by the solvent in the first series. Additional experiments suggest that sampling induces the formation, from PUF, of compounds mutagenic upon extraction with methanol. The study leads to the provisional conclusion that no volatile mutagens could be demonstrated in ambient air sampled by the use of PUF as an absorbent, notwithstanding the clear-cut effects of the filter extracts and the presence of volatile PAH in the PUF extracts.