Hematological Parameters, Blood Heavy Metal Levels, and Socio-Demographic Risk Factors among Occupational Metal Scrap Workers in Benin City, Nigeria: A Cross-Sectional Study

Abstract

Background: Heavy metals such as lead, chromium, cadmium, and nickel are widely distributed in the environment due to rapid industrial growth and poor waste management. Occupational metal scrap workers are particularly vulnerable.

Methods: A cross-sectional analytical investigation was conducted in the Iya-Ero area in Benin City, Nigeria. Fifty (50) male volunteers were enrolled: thirty (30) occupational metal scrap workers and twenty (20) age-matched, non-exposed controls. Complete blood counts and blood heavy metal levels (lead, chromium, cadmium, and manganese) were measured. Independent t-tests and Pearson correlation analyses were utilized for statistical evaluation.

Results: The white blood cell count was significantly higher in the exposed group (6.90±1.70 x 10³/μL) compared to the control group (4.93±1.60 x 10³/μL) (p < 0.05). The percentage of lymphocytes was significantly lower in the exposed group (42.80±8.59%) than in the control (45.90±7.50%) (p < 0.05). Blood lead (3.00±0.90 μg/dL vs 0.65±0.15 μg/dL) and chromium (1.61±0.40 μg/dL vs 0.60±0.13 μg/dL) levels were significantly elevated in the exposed group (p < 0.01).

Conclusion: Occupational metal scrap workers in Benin City demonstrated significantly higher blood lead and chromium levels, accompanied by altered white blood cell counts. These findings suggest potential inflammatory responses associated with occupational exposure. Large-scale longitudinal studies will be needed to ascertain the findings from this research work in order to promote more informed health interventions in occupational exposed subjects.