Decades of repeated occupational exposure to asphaltic fumes and coal tar pitch could possibly lead to some very hazardous health effects.
The controversy surrounding asphalt compounds used in roofing is focused on the production of very small particulates discharged as volatile organic compounds (VOCs) in the fume generated by heating asphalt. A fume is an extremely small, solid particle with a diameter of 0.1 to 0.01µ (micron). One micron is a millionth of a meter.
Any adverse health effects asphalt workers might incur are probably due to many years of exposure to these fumes. These VOCs are created by condensation from the gases resulting from the high temperature of the asphalt in the dip and pump kettles. These emissions may contain high levels of polycyclic aromatic hydrocarbons (PAHs). The benzene molecule is the basic aromatic hydrocarbon. Similarly, polycyclic (benzoidal) aromatic compounds (PACs) are also formed by combining sulfur, nitrogen and oxygen in the refinement process.