A Cross-Sectional Study of Heavy Metal Presence and the Health Implications among Automobile Repairers at Benin City Metropolis, Nigeria

Abstract

Background: Heavy metal exposure may manifest as neurological, dermal, immunological, cardiovascular, renal, hepatic, hematological, respiratory effects, and cancers. Automobile repairers are workers who are engaged in adjusting, repairing, and overhauling automobiles. Entry of heavy metals and chemicals into the bodies of automobile repairers through the airways, the skin, and by accidental ingestion could be greatly reduced if they adhered to regulations and standard operating guidelines that require them to wear personal protective equipment while on duty. Purpose: Automobile repairers are a group of artisans who are routinely exposed to heavy metals and petroleum products. In many countries, workplace safety protocols are either not available or are not adhered to. The objective of this study was to evaluate the serum levels of some heavy metals, hematological indices, and some biochemical parameters of automobile repairers vis-à-vis the health implications. Methods:  The study was conducted in August 2022 in Egor Local Government Area (LGA), which is one of the LGAs in Benin City metropolis, Edo State, Nigeria. A total of 45 automobile repairers, consisting of motor mechanics (27), panel beaters (7), automobile electricians (2), and spray painters (9) who consented and met the inclusion criteria, were selected from workshops within Benin City. A structured questionnaire was used to obtain their biodata. Hematological indices, serum concentrations of lead (Pb), mercury (Hg), arsenic (As), copper (Cu), electrolytes and urea, liver function enzymes, and lipids were estimated and compared with control data from similar studies. Results: All the respondents had at least primary education. The majority (71.7%) used protective gadgets. The serum levels of Pb, As, and Cu were significantly (P<0.0001) elevated, and 93.3% of the subjects had higher Pb levels above the normal range. Hemoglobin (P<0.0001), platelet (P<0.0003) and white blood cell count (P<0.0004) were all lower than control, although most subjects were within the normal range. Hematocrit, mean corpuscular hemoglobin concentration, and granulocytes were not significantly different from control. The levels of Na+, K+, Cl-, HCO3-, urea, aspartate transaminase, globulin, total cholesterol, triglycerides and LDL-cholesterol were all significantly elevated. A larger proportion (66.7%) of the respondents had LDL-cholesterol levels above the upper limit. Conclusion: The elevated levels of the assayed heavy metals and the derangement of hematological, renal function parameters, and lipids indicate insidious processes that would adversely affect the health of the automobile repairers. The study points to the need for these workers to be more concerned about occupational safety.