Ecological and Health Risk Assessment of Trace Metals in Waters from North-West Zone of Akwa Ibom State, Nigeria

Document Type : Original Research Paper


1 Department of Zoology and Environmental Biology, College of Natural Sciences, Michael Okpara University of Agriculture, Umudike, Abia State, Nigeria

2 Faculty of Health Sciences, National Open University of Nigeria, Akwa Ibom State, Nigeria



Metals contamination in water is becoming a threat to human health. The studies ecological and health risk assessment of trace metals was conducted in seven water bodies in Akwa Ibom State, between May 2021 and April 2022 (twelve months), to evaluate the levels of trace metals contaminant and suitability of the waters for human consumption. Six trace metals were assessed in the water samples; using atomic absorption spectrophotometer after digestion. Pollution indices such as heavy metal pollution index, comprehensive pollution index, contamination index and health risk assessment for non-carcinogenic were employed. The findings were compared with Nigerian Standard for Drinking Water Quality. The mean concentration of some metals (Pb, Cd, Cr, and Cu) in some stations were exceeded the standard limits, while Fe and Ni exceeded the acceptable limits in all the stations, due to anthropogenic activities. The values for HPI in stations I, II, IV and VII were exceeded the threshold of 100, ranging between 61.4 and 743.5; CPI ranged from 1.05 to 3.72, while Cd ranged from 0.94 to 16.3, indicated that the water bodies are highly contaminated. The CDI and HQ values for Fe, Cd, Cr and Cu exceeded the oral toxicity reference dosage of contaminant and stipulated threshold (1) for HI in some stations both in children and adult, indicated that the water bodies are not suitable for human consumption. The findings call for concern regarding their effects on human health, which could be detrimental to the people drinking from these water.


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