[The behavior of Penicillium spores in air filters for automobile interiors. Testing of germination and propagation under static and dynamic test conditions using microscopic and microbiologic methods].

Microbiological tests show, that 3-layer car-air filters (Polycarbonate-microfiber type AF 901) are not a substrate for fungi frequently present in outdoor air. Microscopical investigations of the filter samples, which were exposed to Penicillium spores under static and dynamic conditions show no growth and no germination. The particles of dust which are trapped in the car-air filter, have no components with fungicidal effect, but include substances for inhibition of spore germination. In static model experiments (without air stream) already driven car-air filters were tested and fungal growth was obtained by very high concentrations of substrate and spores. On the other hand, however, in dynamic tests (with air stream) fungal growth cannot be detected, because the liquid humidity is absent.