Investigations on the carcinogenic burden by air pollution in man. XIII. Assessment of the contribution of passenger cars to air pollution by carcinogenic polycylic hydrocarbons.

A total of 100 passenger cars were tested with regard to the amount of polycyclic aromatic hydrocarbons (PAH) emitted during the EUROPA-Test (E.-Test, simulate city driving; 4 times 195 s). As determined by frequency of registration, the 20 most common car models were chosen. Each model was represented by 5 cars. The total amount of selected 14 PAH emitted by all test vehicles during an E.-test is in the range of 1-16 mg. As can be seen from the average of fuel consumption (409.4 g/E.-test) and benzo(a)pyrene emission (41.6 mug/E.-test), 1000 kg of burned fuel yield 101 mg of benzo(a)pyrene. Based on the consumption of gasoline in 1973 in West Germany (18508200 tons), an annual amount of 1.85 tons of benzo(a)pyrene is produced by gas engine vehicles. However, the biological effect of the automobile exhaust is still larger because it contains additional carcinogenic PAH. - A statistical evaluation of the results shows that different car models can not be distinguish by their PAH emission. When evaluating individual vehicles after 5 repeated E.-tests, the margin of error for any single PAH is between 6.3-10.9% (variation coefficient) for this car. A larger margin of error is obtained by pooling 5 different vehicles of the same model.