Cytogenetic biomonitoring of road paving workers occupationally exposed to polycyclic aromatic hydrocarbons

Road pavement workers are exposed to many known carcinogens in their complex occupational environment. The study makes an attempt to investigate exposure to polycyclic aromatic hydrocarbons (PAH) from the bitumen fumes among the road pavement workers engaged in different pavement sites at Coimbatore, Tamil Nadu and to thereby determine the genotoxic effects associated with it. The study included 36 road pavers and 37 control subjects with similar mean ages, smoking prevalence and alcohol consumption and was analyzed for DNA damage in blood leucocytes by Micronucleus assay (MN) and the Comet assay. The mean urinary 1-OHP concentration in road pavers (1.68 ∓ 0.93) was significantly higher than in controls (0.55 ∓ 0.42). The results of MN test and comet assay showed that the mean micronuclei rate in workers was significantly higher than those in controls (P <0.05). The results of our study indicated that the genetic damage was detectable in road paving workers occupationally exposed to bitumen and also demonstrate the high sensitivity of comet assay to assess early oxidative effects induced by exposure to bitumen fumes at low doses and confirm the suitability of urinary 1-OHP as a biomarker of PAH exposure.