HAEMATOTOXICITY IN FUEL STATION WORKERS EXPOSED TO PETROLEUM AIR POLLUTANTS: INFLUENCE OF NQO1 GENE POLYMORPHISM

Abstract

Fuel station workers are chronically exposed to petroleum derivatives air pollutants, mainly benzene, primarily through inhalation during vehicle refueling. The adverse health effects of benzene exposure may be primarily related to impairment of haemopoietic system with bone marrow depression. We studied haematological changes among fuel station workers with different NQO1 genotypes in Sudan. The study included 100 fuel station workers, chronically exposed to variable concentration of petroleum derivatives air pollutants during their work on the fuel filling station, there blood cell count (determined by Sysmex KX-21N) and NQO1 genotypes (determined by PCR-RFLP) were determined and compared with 50 normal (non-exposed) subjects as control. Mean TWBC was significantly lower, with lower neutrophils count, among fuel station workers than controls (P value=0.043 and 0.004 respectively). Mean platelet count was also lower among cases than controls (P value=0.001), further reduction in the platelets count was observed among workers with mutant NQO1 genotypes. Significant correlation was observed between work duration and RBC count (P value=0.004), Hb level (P value =0.024) and PCV (P value=0.016). In conclusion, we have demonstrated robust changes in TWBC count, neutrophils count and platelets count among fuel station workers which could be attributed to benzene-containing gasoline exposure at workplace. Lower platelets count among workers with mutant NQO1 genotypes highlighted an evidence of increased susceptibility to benzene-containing air pollutants haemotoxicity among such workers.
Key words: Haematotoxicity, fuel station workers, NQO1, Sudan.