Polycyclic aromatic hydrocarbons
'Polycyclic aromatic hydrocarbons (PAU, PAH) are suspected or proven carcinogens. They are difficult to detect, mixtures of these substances are usually determined, and the part of PAHs that is bound to the respirable fraction of the aerosol is also determined - from it they reach deep into the respiratory tract. The source of PAHs in buildings are certain activities (among others smoking), but they also enter the body through food (from burnt fats) and from the outdoor environment (burning of fossil fuels, exhaust gases, burning of household waste in domestic fireplaces).
An example of a PAH can be benzopyrene, which in its chemically pure form does not cause malignant growth; however, if it is bound to the respirable fraction of the aerosol, it causes bronchogenic carcinoma.
