Occupational exposure to petroleum products and its effects on heavy metal metabolism in automobile mechanics

In fuel filling station attendants various pathological events have been linked with exposure to petroleum products, with the severity of these events correlated with blood levels of benzene, toluene, ethylbenzene and xylene (BTEX). BTEX are volatile compounds, so exposure through the nasal route is possible yet in auto-mechanics because dermal exposure is also pronounced, this may lead to the presence of non-volatile petroleum product constituents (e.g. heavy metals) in their systemic. The aim of the study is estimate heavy metal levels in serum of auto-mechanics.  Random sampling technique was employed to recruit participating age-matched control and auto-mechanics. Questionnaire was administered, with focus on demographic- age, lifestyle, work experience in years, and work hours, and the type of protective gear used during work hours. Serum obtained from 5 mL of venous blood was used to estimate levels of lead, aluminium, nickel, silicon, cadmium, and arsenic by atomic absorption spectrometry. Student’s t-test was used to determine statistical difference between the means of both groups, p ≤ 0.05 was considered significant. The duration of exposure in years was 6- 9 (range) and work-hours (automobile mechanics) per day was an average of 8 hours. All the heavy metals estimated were significantly higher in automobile mechanics compared with control subjects. There are indications that elevated levels of lead, aluminium, nickel, silicon, cadmium, and arsenic is associated with this occupation.