The level of trace elements in tripoli city groundwater

Groundwater samples from different regions of Tripoli city (Libya) were analyzed for environmental control purposes. The concentrations of several trace elements (As, B, Ba, Be, Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Sb, Sr, and Zn) were determined by means of ICP-OES and AAS methods. The obtained results were also compared with the European and Canadian standards, as well as with the Egyptian ground, Nile, and drinking water concentrations. As a result, the detected elements were classified into three different groups. The first group of elements, (Na and Sr) was found to have high concentrations. The second group of elements, (Ba, B, Ca, Cr, Cu, K, Li, Mg, and Zn) had comparable concentrations. The third group of elements, (As, Cd, Fe, Mn, and Sb), showed low concentrations. The observed high concentrations of some elements, in particular Sr, and the lower concentrations of the others, such as Fe and Mn are relevant to their levels in Tripoli city soils. In addition to the above elements, some inorganic ions, (NH4+ , NO2- , and NO3-) were also detected using ion chromatography (IC). The elevated concentration of NO3- is mainly due to various industrial activities, the use of fertilizers, and/or pollution from sewage. The concentration of the other inorganic ions, (NH4+ , NO2-) was found to be within the international standard limits. The natural radioactivity in the samples has also been investigated using gamma-spectrometry and was found to be very low.