Health Risk Assessment on Heavy Metals Ingestion Through Groundwater Drinking Pathway for Residents in an Oil and Gas Producing Area of Rivers State, Nigeria

Abstract

In the study, health risk assessment on heavy metals ingestion was presented through the groundwater drinking pathway for residents in an oil and gas producing area of Rivers State, Nigeria. The level of the ground water pollution was examined, the quality of the borehole and the well water was assessed and the quality of the ground water pathway for the resident in the oil and gas producing area was determined and compared with the national and international standards for the drinking water. This study adopted both the field and laboratory experimental analysis of physical and chemical parameters. Water samples were analyzed for Physico-chemical parameters following acceptable methods to determine the compliance, and the results were analyzed according to drinking water guidelines. Interestingly, the results show that the ground water contained high amounts of turbidity (21.5 NTU, 23.00 NTU and 19.0 NTU in the borehole water and well water), iron (5.3 mg/L in the ground water and 6.98 mg/L in the borehole water) and pHs of all water samples were acidic in the study area. These results show that ground waters including the borehole and the well waters of the study area had acquired reasonable levels of pollution. Whereas, other values were found to be lower or above and corresponding to the acceptable threshold limit values for the drinking water set by consensus standards. A high value of turbidity due to suspended minerals is the cause for milky-white colour. Hence, ground waters in the study area are mainly unsuitable for drinking (containing iron, pH and turbidity). This study clearly advises that some health deteriorating chemicals in the drinking water were at dangerous level and; therefore, the water quality could be a major health menace for residents of the oil and gas producing area of Rivers state. Furthermore, additional researches in medical test to ascertain the health of the people are recommended in this study. Comprehensive groundwater monitoring and adequate treatment should be implemented. The government should carry out clean-up exercise immediately because there is oil spill to prevent infiltration of oil into the groundwater. There is also a need for the continuous monitoring and auditing of water quality in the oil producing areas so as to protect the men and the environment.

Keywords: Health Risk, Heavy Metals, Oil Spill, Ingestion, Groundwater, Rivers State, Nigeria