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Genotoxicity in filling station attendants exposed to petroleum hydrocarbons.

OBJECTIVES
Biomonitoring of exposure in workplaces has gained importance in evaluation of human health hazards. Since occupational exposure to petroleum hydrocarbons may have deleterious effects, genotoxicity risk among 200 fuel filling station attendants (FFSAs) and 200 matched controls was investigated.


METHODS
The probable genetic damage was determined by comet assay and micronucleus test in peripheral blood lymphocytes (PBL) of study subjects. Air and blood sample analysis was done to estimate the benzene, toluene, and xylene (BTX) concentrations using gas chromatography-mass spectrometry. The effect of exposure on antioxidant enzymes was also studied by determining the levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and rate of lipid peroxidation measured as concentration of malondialdehyde (MDA) formed.


RESULTS
The results of the present study suggest that there was a statistically significant increase in mean comet tail length (25.09 versus 10.27 μm) and frequency of micronuclei in PBL (11.83 versus 5.83 per thousand; P < 0.05) of FFSAs as compared to controls. BTX concentrations were found to be significantly higher in ambient air of petrol pumps and FFSAs showed elevated levels of these compounds in their breathing zone in comparison to controls (P < 0.05). Blood BTX levels were found to be significantly enhanced in FFSAs. SOD and GPx were significantly decreased with an increased rate of CAT and MDA in FFSAs as compared to controls.


CONCLUSIONS
The results of our study suggest that exposure to BTX has the potential to cause genetic changes in the exposed subjects. The data highlight the need to maintain safety measures and intervention to minimize exposure.