Cadmium and Lead Induced Proinflammatory Cytokine Polarization in Petroleum Products Occupationally Exposed Nigerians

The toxicological effects of petroleum product had been associated with various metabolic defects such as cardio-vascular attacks. But there is limited information about the cytokine responses of individual who are occupationally exposed to petroleum products in Nigeria. The study was aimed at evaluating the cytokine responses to the accumulation of cadmium, lead, zinc and copper in the petroleum products using blood levels of interleukin-1 alpha, interleukin-4, cadmium, lead, zinc and copper in occupationally exposed individuals in Abuja, Nigeria. The case-control study randomly selected sixty-three occupationally exposed (test group) and sixty non exposed individuals (control group). The occupationally exposed subjects, consisting of twenty-four automobile mechanics (AM), eighteen generator mechanics (GM) and twenty-one petrol station attendants (PSA) in filling stations who consented to participate in this study. Cytokine levels were determined by enzyme-linked immunosorbent assay method. Heavy metals were analyzed by atomic absorption spectrophotometer method. Full blood count was done using hematology auto-analyzer. All numerical results were analyzed with one-way ANOVA with post hoc multiple comparisons test while student’s t- test was used to compare independent variables. Cadmium levels were significantly higher in AM and PSA (p<0.002) while lead levels were significantly higher in AM and GM (p<0.04) as compared with the control group. Zinc and copper levels were significantly lower in AM and GM as compared with the control group (P<0.002) but within the acceptable levels. Granulocytes count was significantly higher in GM and PSA, whereas, red blood cells count and packed cell volume were significantly lower in GM and PA as compared with control group (p<0.001). IL-1α and IL-4 levels were significantly higher in AM, GM and PSA as compared with the control group (p