Evaluation of trivalent and hexavalent chromium retention on Ain oussera soil by radiotracer technique

Even if the heavy metals are naturally present in the soil. It is the anthropogenic activity which is responsible for the modification of their concentrations. This can lead to a contamination able to reach even the ground water, and the food chain by passage through the plants. Pollutant metals are absorbed by the living organisms according to various processes. The absorption of these elements is function of the chemical composition. Their principal targeted organs are kidneys, liver and secondary muscles and bones. Among the principal pollutants metal: Cu, Pb and Cr. They create particular alarming problems. These elements are non-biodegradable by nature. They have a strong ecotoxicity and could be implied in much pathology: related to central nervous system, liver, embryonic kidneys, and also cancers and malformations. The main objective of this study is to evaluate trivalent and hexavalent chromium behavior in soil sample from the Ain Oussera area, near the Essalam reactor site. Batch sorption method was used to evaluate the retention of chromium in soil. The sorption of radionuclide was investigated using Cr51 obtained in Essalam reactor from Cr50 (n,γ)Cr51 as a radiotracer. Gamma spectrometry was employed to measure activity and determines the percentage retained of chromium. In order to characterize the mineralogical composition of this soil, neutron activation analysis was used. Effects of pH, temperature, and pollutant initial concentration were investigated. The maximum adsorption percentage reached for Chromium (III) and (VI) is respectively 90% and 34%.