Measurements of benzo(a)pyrene in the city of Bombay for the evaluation of carcinogenic risk.

Cigarette smoking, environmental chemicals and ionizing radiations are the three factors known to cause cancer in human beings. The relative importance of each of these is being constantly evaluated. There is an urgent need to monitor the environmental carcinogens on a large scale to assess the role of environmental chemicals in the incidence of cancer in human populations. Polycyclic aromatic hydrocarbons (PAH) are released into the atmosphere as a result of fossil fuel combustion and some of the PAH (e.g. benzo(a)pyrene) are recognised carcinogens. Measurement of benzo(a)pyrene in urban, suburban and rural regions of Bombay is carried out in order to evaluate the possible correlation with lung cancer incidence among different population groups. The variations in the concentration at the three sampling locations are discussed. The wide differences in the concentration at different locations seem to be very suitable for epidemiological investigations.