Exposure Neuroepidemiology Study among Occupational Groups with High Exposure to Aviation Emissions

Abstract

Aviation industry personnel working at the airports in Pakistan are confronted with neurasthenic and physical problems mainly because of unprecedented exposure to jet fuels and also there is no proper health monitoring services are extended to them. We aimed to assess dermal exposure of workforce at airports to jet propellant (JP) fuel (e.g. JP4, JP5, and JP8) which contains a complex of mixture of Polycyclic Aromatic Hydrocarbons (PAHs). To document the extent of acute toxic exposure levels, protective strategies, working hours and job nature were used as predictors. Among aviation workforce members, who work for more than six hours per day, we took both skin pad and urine samples to measure dermal exposure by PAH and subsequent secretion through body. To detect biological marker for dermal exposure urinary pyrene metabolite was quantified. The results show that workers at the airport have high jet fuel dermal exposure. However, the mean pyrene exposure levels were reduced to 33% when they use masks during work. Urinary 1-hydroxyprene was detected as the biological measure to quantify the internal exposure to PAHs present in JP fuels whose concentration was relatively low (range 35 and 174 nmol) when compared to dermal exposure levels. Workers exposed to 6 hour per day or more had significantly high prevalence of physical disorders (OR=3.17, 95% CI=1.33–7.12). Neurasthenic symptoms (e.g. energy loss, fatigue, fainting, twitching, sleeplessness, irritability, body aches) were found in 58% of the subjects and were associated with years of involvement in job. In aviation industry, working at the airport for ten years or more attributed substantial development of neurasthenic effects (OR=3.85, 95% CI=1.71–8.84). Results of multiple regression analysis revealed mass balance between dermal pyrene dose and 1-hydroxyprene excretion that confirmed the relevance of the dermal exposure route.