Heavy Metals Pollution and Trend in the River Nile System

Abstract

Due to large amount of sewage of increased population, excessive use of pesticides and fertilizers in agriculture, rapid development of chemical and petrochemical industries and mining activities around the River Nile and its tributaries White Nile and Blue Nile, chemical water quality of those Niles are expected to be deteriorated. River Nile and its tributaries are among the main Khartoum state drinking water supply resources. The main aim of this study is to assess the concentration of heavy metals (in terms of lead Pb, cadmium Cd and chromium Cr) in the River Nile, White Nile and Blue Nile and compare the results of water analysis with the WHO guideline values. And then investigate the trend of heavy metals (in terms of lead and cadmium) in the White and Blue Niles. Three composites samples were collected from River Nile, White Nile and Blue Nile and examined using ICP by applying SOP- CIL-SP-02 test method to evaluate the concentration of heavy metals. Also a comparison study with previously obtained results was carried out. Heavy metals concentration in the River Nile, White Nile and Blue Nile in terms of cadmium, and chromium were found to be within the level according to WHO guidelines for drinking water, but for lead it was in the marginal level. However when comparing the concentrations obtained in this study with those in two previous studies, it was revealed that there is a regular built up of heavy metals concentration in the River Nile tributaries; White Nile and Blue Nile.