Occupational pulmonary hazards due to chronic exposure to benzene

ABSTRACT

This was a cross-sectional study performed in Khartoum state on 79 workers at petrol stations in October 2003. The population was divided into two groups, one exposed to benzene for 5 years and more and another exposed for less than 5 years, then both groups were compared to a control of unexposed subjects. Lung function was evaluated by a questionnaire and lung function testing using the microplus spirometer. Provocation and reversibility tests were performed using benzene and salbutamol respectively and a full history before and after exposure to benzene was taken. Benzene provocation test was performed in some unexposed subjects. Both restrictive and obstructive pulmonary trends were evident by the reduction of FVC, FEV1 and PEFR in benzene exposed groups which was directly proportional to the duration of the exposure. The results showed significant reduction in FEV1 and PEFR in benzene exposed workers minutes after benzene inhalation [benzene provocation test] while the reductions were insignificant in benzene unexposed control indicating an increase in airways sensitivity to benzene in chronically exposed subjects than non-exposed. 21% of the workers had reported respiratory problems following work at petrol stations