Determination Of Heavy Metals and Radon Concentration in Soil and Water Samples from Wadi-B Jere Oil Exploration Sites in Maiduguri, Northeast Nigeria

Abstract

Radon gas and heavy metals are two significant risk factors that can cause lung cancer. Wadi B, a locality in Jere local government of  Borno state, is an area where oil exploration is underway. There is a potential health risk of contamination of the drinking water and soil  samples in the area. To investigate radon concentration and heavy metal contamination, several samples of water from wells and  boreholes, as well as soil samples, were collected for analysis. The analysis was conducted using liquid scintillation (LSC) and atomic  absorption spectrometry. The result of radioactivity analysis using LSC shows that water samples have varying levels of radon  concentration ranging from 17.77 Bql-1 to 22.50Bql-1 which exceeded the maximum contaminant levels of 11.1Bq/L set by the USEPA  1999 and the world average value of 10Bq/L set by the World Health Organisation (WHO 2004). The mean annual effective cancer risk of  radon intake varied across sampling points, ranging from 0.164, 0.246, 0.287 to 0.130, 0.218, and 0.227 for adults, children, and infants,  respectively, with mean values of 0.146, 0.219, and 0.255. The mean values of excess lifetime cancer risk (ELCR) associated with radon  inhalation and ingestion for adults, children, and infants were 0.0005110, 0.0007660, and 0.0008930, respectively. Moreover, elevated  conductivity and total dissolved solids in water samples suggest potential contamination, exceeding the recommended limits set by the  World Health Organization. On the other hand, Heavy metals analysis shows a mean value of ELCR 0.125009 for adults and 0.000063 for  infants. Results showed that heavy metal concentrations in soil samples exceeded permissible limits for all metals except chromium and  lead, with the order of concentration being Cr < Cd < Pb < Cu < Zn. These findings underscore the need for ongoing monitoring and  remediation efforts to mitigate environmental and health risks in Wadi B