Assessment and speciation of chromium in groundwater of south Sohag Governorate, Egypt

Groundwater pollution by hexavalent chromium (Cr (VI)) becomes a very serious and challenging issue owing to its high toxicity. So, the present work was conducted is to investigate Cr (VI) occurrence and origin, for the first time, in the groundwater of Sohag Governorate, Egypt. Therefore, 18 groundwater samples were collected and chemically analyzed. The results indicated that the groundwater chemistry dominated by HCO3 and Na+ while Ca-Mg-Cl-SO4 and Ca-Mg-HCO3 were the main water types in the study area. The unconfined part of the studied aquifer contains elevated levels of the studied parameters than the semi-confined part owing to the hydrogeological condition variation. Generally, the groundwater samples contain unacceptable concentration (>50 μg/l) for drinking purposes of Cr (total and Cr (III). While, the concentration of Cr (VI) were ranged from 12 μg/l to 58 μg/l with only one sample >50 μg/l. Contamination of Cr (VI) in the groundwater can be attributed mainly to human activities with a minor contribution of geogentic sources. Finally, it is important to study the accumulation of Cr (VI) in water resources and its possible effects on human health. [Display omitted] •The current work declared, for the first time, the distribution of the carcinogenic Cr (VI) in Egypt groundwater.•The results emphases the role of MnO2 the oxidation of Cr (III) into Cr (VI).•The pH plays great role in the distribution of Cr species.