Liver Damage Risk Assessment Study in Workers Occupationally Exposed to E-waste in Benin City, South-South Nigeria


1 Department of Chemical Pathology, Toxicology and Micronutrient Metabolism Unit, College of Medicine, University of Ibadan, Ibadan, Nigeria

2 Basel Convention Coordinating Centre for Training & Technology Transfer for the African Region & Department of Chemistry University of Ibadan, Oyo State, Nigeria

3 Department of Medical Laboratory Sciences, School of Basic Medical Sciences, College of Medical Sciences, University of Benin, Benin City, Nigeria

4 Chemical Pathology Laboratory, Faith MediPlex Hospital, Benin City, Nigeria


  Large volumes of mostly irreparable electronic waste (e-waste) are shipped to Africa on a monthly basis, of which Nigeria receives the largest share. E-waste management practices in Nigeria have remained completely primitive until date; and e-waste workers have little or no occupational safety knowledge and devices. The thousands of chemicals in e-waste have been reported to be toxic to human health in any degree of exposure. The present study has assessed the risk of liver damage in workers occupationally exposed to e-waste in Benin City, South-south Nigeria in 2014. Serum activities of liver enzymes [alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyltransferase (GGT) and alkaline phosphatase (ALP)]; and levels albumin (ALB), total bilirubin (T/Bil) and conjugated bilirubin (C/Bil) were determined using standard colorimetric methods. Serum Alpha fetoprotein (AFP) was determined using ELISA in Nigerian e-waste workers (n=63) and in age-matched unexposed participants (n=41) in Benin City. The results showed significantly raised activities of enzymatic biomarkers of liver damage (ALT, AST, ALP and GGT) in the e-waste group compared with the unexposed participants. There was no significant difference in the levels of ALB, T/Bil and C/Bil between exposed and unexposed participants. AFP levels in e-waste workers (3.56 ± 0.34 ng/mL) were significantly different compared with the unexposed group (2.14 ± 0.80 ng/mL) (P< 0.045). The significantly elevated cancer risk biomarker (AFP) and the enzymatic biomarkers of liver damage observed in the Nigerian e-waste workers studied may be associated with occupational exposure to known carcinogens and hepatotoxic metals in e-waste.


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