Toxicological investigation of airborne particulates indoor and outdoor

In 51 selected households in the greater Munich area the airborne particula tes were collected inside and at the same time as reference outside. The ai rborne particulates were extracted and tested in biological assays (neutral red assay with fibroblast-cells and human lung cells and mutation assay by Ames) for cytotoxic and mutagenic effects. The toxicity outside was highes t in the centre of Munich and decreased to the suburbs. In 2/3 of the house holds investigated the indoor air was more toxic than the air outside. The toxicity was on an average inside about 1/3 higher than outside. Noticeable was the much higher toxicity of indoor air in smoker households. Compared to non-smoker houses the toxicity inside was three times higher. So smoking was the highest perceptible influence. In the investigation of mutagenic e ffects only qualitative statements could be given (positive or not positive in the test). Eleven from 51 households were positive inside and five outs ide.