Roofers have higher levels of cancer Colorado - Arabstoday Roofers and road workers who use asphalt are exposed to high levels of polycyclic aromatic hydrocarbons, which may up their cancer risk, U.S. researchers say. Dr. Berrin Serdar of the Colorado Cancer Center and the Colorado School of Public Health said roofers have higher PAH blood-levels after a shift than before and that these high levels of PAHs are linked with increased rates of DNA damage, and potentially with higher cancer risk. \"We\'ve known for some time that roofers and road workers have higher cancer rates than the general population, but we also know roofers have a higher rates of smoking, alcohol use and higher ultraviolet radiation exposure than the general population, and so it\'s been difficult to pinpoint the cause of higher cancer rates -- was it due to higher PAHs or is it due to lifestyle and other risk factors?\" Serdar asked. Serdar and colleagues at the University of Miami, studied 19 roofers from four work sites in Miami-Dade County and tested their urine -- before and after a 6-hour shift. After acute exposure to hot asphalt, PAH biomarkers were elevated and were highest among workers who didn\'t use protective gloves and workers who reported burns. \"We can\'t say with certainty that exposure to hot asphalt causes roofers\' increased cancer rate,\" Serdar said in a statement, \"but that possibility is becoming increasingly likely. Hot asphalt leads to PAH exposure, leads to higher PAH leads to higher PAH biomarkers, leads to increased DNA damage.\" The study was published in the British Medical Journal Open.