DNA damage in humans exposed to environmental and dietary polycyclic aromatic hydrocarbons

The paper describes recent research on human DNA damage related to environmental and dietary polycyclic aromatic hydrocarbon (PAH) exposures. The study populations either represent general populations of large geographical regions, or their exposure situation may have relevance to the general population. In Silesia, Poland, and Northern Bohemia, Czech Republic, where coal-based industry and domestic heating are the major sources of PAHs, significant differences have been observed in white blood cell DNA adducts and cytogenetic biomarkers between environmentally exposed and rural control populations, and significant seasonal variations of DNA damage have been detected. Bus drivers, traffic policemen and local residents have been involved in biomarker studies in Copenhagen, Athens, Genoa and Cairo, and differences have been measured in the level of DNA damage of urban and rural populations. Burning of smoky coal in unvented homes in Xuan Wei region, China, causes high PAH exposure of residents, which has been reflected in DNA adduct levels in different tissues. Indoor wood burning in open fireplaces did not increase human DNA adduct levels. Oil-well fires left burning in Kuwait after the Persian Gulf war created an unprecedented environmental pollution. However, insignificant environmental PAH levels were measured several miles from these fires. Aromatic and PAH-DNA adduct levels in white blood cells of US Army soldiers were lower during their deployment in Kuwait, than in Fulda, Germany, where they were stationed before and after serving in Kuwait. The contribution of dietary PAH exposure to blood cell DNA adduct levels had been demonstrated in studies in which volunteers consumed heavily charbroiled beef. Environmental tobacco smoke did not cause detectable changes, as measured by 32P-postlabelling, in DNA adduct levels in non-smokers. In the reviewed studies, observed DNA adduct levels were generally in the range of 1 to 10 adducts, and not higher than 40 adducts in 108 nucleotides. Typically, 1.5 to 3-fold differences have been detected in DNA adduct levels between the exposed and control groups.