Assessment of oral and dermal health risk exposures associated with contaminated water resources: an update in Ojoto area, southeast Nigeria

In this paper, the oral and dermal health risks of potentially toxic elements in water samples collected from Ojoto area in southeast Nigeria were studied using HHRISK code and water quality index. The water samples were analysed for physicochemical parameters based on standard guidelines. Average concentration of the potentially toxic elements in the water was in the order: Pb2+ > Fe2+ > Zn2+ > Ni2+ > Cr3+. To assess the level of surface and groundwater pollution, water quality index was calculated. Results of the water quality index suggest that 11% of the water samples are in good condition; 25% have poor quality, 3% have very poor quality, and 53% have quality that is unfit for human consumption. The HHRISK code was used to quantify the health risks associated with the use of the water resources. Results revealed that most of the water samples expose their users to carcinogenic and non-carcinogenic health risks. Cumulative non-carcinogenic risk scores (for both children and adults) and the majority of cumulative carcinogenic risk values were found to be above regulatory limits. The adult population is exposed to lower non-carcinogenic and carcinogenic health risks, implying that children are more vulnerable. The water supplies are of substandard quality and could cause serious health issues when ingested than when used for bathing and washing purposes. Simple linear regression models showed positive agreement between the results of the WQI and HHRISK code. To safeguard the water resources, avoid additional water contamination, and reduce public health hazards associated with poor water quality, strategic mitigation strategies are recommended.