Determination of Different Trace Heavy Metals in Ground Water of South West Bank/Palestine by ICP/MS

Abstract

Heavy metal contamination of the groundwater of south West Bank in Palestine was assessed. The groundwater samples were analyzed for different trace heavy metals (Tl, Pb, Bi, Cr, Mn, Co, Ni, Cu, Zn, Mo, Ag, and Cd), and Al content by ICP/MS. This study was conducted to determine the water quality of ground water which is used for drinking in the study area. Water samples from ten groundwater wells were obtained in four different dates of the year (October 2012, November 2012, March 2013, and April 2013). Three water samples were obtained from each well for each sampling date. A total of 120 water samples were collected from the ten wells. The samples were analyzed for their pH, electrical conductivity, total dissolved solids, and different trace metals content. The pH, electrical conductivity, and total dissolved solids of all water samples were found to be within the US Environmental protection Agency limits. Results showed that Pb, Al, Cr, Co, Ni, Cu, Zn, and Mo were detected in all water samples analyzed in this study, while Tl, Bi, Mn, Ag, and Cd were detected in 80%, 88%, 90%, 75%, and 95% of the water samples analyzed in this study, respectively. In general, 93% of all samples analyzed contained one or more of the 13 metals studied each in varying concentration. Furthermore, results showed that the concentration of Cr, Mn, Ni, Cu, Zn, and Mo is within the allowed WHO limits in drinking water. However the concentration of Pb Cd, and Al are found to be higher than the allowed WHO limits in 40%, 8%, and 33% of the water samples analyzed in this study, respectively. Statistical analyses showed that concentrations of the metals studied in this study vary significantly between the ten ground water wells, indicating that the wells analyzed in this study is different from each other in terms of heavy metal content. Additionally, from the statistical results obtained, it was found that there is a significant difference in the concentration of the metals in each well for the four sampling times (October 2012, November 2012, March 2013, and April 2013), denoting that metal concentration in the wells vary significantly with sampling time. The results obtained from this study suggest a possible risk to the population of the study area given the toxicity of these metals, and the fact that for many people in the study area, ground water is a main source of their water supply.