Determination of Heavy Metals Ni, Cr, Mn and Co in Salt Obtained By Water Treatment and Its Comparison with Rock Salt

Every year more than a third of people of the developed countries disease caused by the food they are having and the mortality rate of disease resulted from the pollutants of food in the developing countries, 2.2 million people have been reported annually. Heavy metals are such environmental pollutants that if human have any face with some of them through the water and food poisoning can be caused chronic and acute venenation. Among them we can mention to some metals like chromium, nickel and cobalt in all kinds of salt. In this research the aim was to determination of some heavy metals amount like Ni, Cr, Mn and Co in the samples of washed salt by water and rock salt by the flame atomic absorption spectroscopy. The amount average of heavy metals for salt washed was like below: Ni (1.860±0.689), Cr (0.345±0.144), Mn (0.171±0.120) and Co (3.747±0.832) (μg g-1) dry weight (Mean±Standard Error) and for rock salt was like below: Ni (2.001±0.021), Cr (2.549±0.011), Mn (0.200±0.025) and Co (9.041±0.100) (μg g-1) dry weight (Mean±Standard Error). By comparison, and paying attention to the difference between the quantities and reducing the amount of elements in the washed salt we can sense the importance of rock salt infiltration. By statistical analysis (t-Test: mail this article-demonstration equal Assuming Variances) we can be found that quantities of heavy metal (chromium, cobalt, manganese) in unrefined salt with quantities of them in refined salt have meaningful difference of P0.05. And also results showed that with washing the rock salt we can see meaningful change in degree of purity 96.96-98.83%.