Polycyclic Aromatic Hydrocarbons (PAH, Coal tars and pitches)
PAHs are a group of chemicals that are found in every industry, especially where substances are burned. Many PAHs are known carcinogens and are ubiquitous in the environment, occurring naturally in some hydrocarbon mixtures deriving from minerals, such as coal or petroleum. They are also generated in processes involving the combustion of any organic matter, including fuels. Coal-tar pitch volatiles, which contain PAHs, are produced during coking, tar distillation, aluminium smelting and downstream uses of tar and pitch.
Exposure to PAHs is associated with non-melanoma skin cancer (NMSC). Available information from the cancer burden study shows very low numbers of cancer deaths (11) and approximately 545 cancer registrations per year.
A research study in 2006 in Great Britain showed that there were no significant exposures to PAHs other than at sites undertaking timer impregnation. A further study to evaluate historical and current exposures to hazardous substances and their controls in the British construction industry is underway to update the available evidence. This evaluation covers many substances one of which is coal tars.
Further information is available by registering on the Occupational Diseases Community site.