Investigation of cadmium content in Iranian rice (Oryza Sativa) :Its weekly intake

Cadmium is one of the dangerous heavy metals which its presence in nature and entrance to humans food chain, causes the serious damage in kidneys, lungs, bones, and also anemia and sometimes hypertension. The major source of cadmium intake is rice for rice eating countries such as Iran. Cadmium in rice comes from soil through plant roots. Thus, Rice may be the best indicator for the environment mentoring of cadmium especially in rice eating countries. The most important sources of soil pollution to cadmium are industrial sludge sewage discharge for increasing its fertility, applying superphosphate fertilizers and etc. At this investigation surveyed Cd content of tarrom rice. A total of 60 samples were collected from four areas of Qaemshahr region in north of Iran (Mazandaran province). The samples were collected in during harvesting of rice in filed. The first step, grains of rice were digested by acid digestion method then were analyzed for cadmium by atomic absorption spectrometer. The results showed that average concentration of Cd in rice was 0.41±0.17 mg/kg dry wt. Notably the Cd content in the rice samples was found to be upper the FAO/WHO Guidelines. We concluded that a substantial exists in Cd contents in the rice of four areas and hence health risk is maximum and this risk will increase to eating other foods such as vegetable, fish and etc and also the situation could worsen in the future. Treatment and remediation of polluted soils and environment, decreasing easing of fertilizer using could reduce Cd intake by plant and consequently health risk.