بررسی میزان فلزات سنگین (کروم- کادمیوم- سرب) در آب آبیاری و برنج رقم طارم تولیدی مزارع شهرهای مرکزی استان مازندران

Background and purpose: Water and soil pollution with heavy metals are among serious ever-growing environmental problems. Human activity accounts for much of the poisonous metals and results in increases soil pollution. There are many factors related to soil and plants properties and environmental issues. Release of heavy metal into food chain in critical densities has harmful metabolic and physiologic effects on living creatures. Materials and methods: Three regions including Movaram Kola, Seyyed Mahalleh, Jouybar Mahalleh Kola located in Sari, Jouybar and Qaemshahr (central regions of Mazandaran province) were investigated to determine the concentrations of heavy metals in paddy fields irrigation and Tarom rice within 2010-2011 agricultural year. Sampling included samples of irrigation with water and rice, and field study for qualitative and quantitative properties of rice. Sampling and test method of heavy metals was in accordance with suggestive method of standard book of method. Finally density of heavy metals of samples was measured using atomic absorption machine. For statistical calculation and quantitative study of data Prism, Stata 11 and t-test were applied. Results: In the studied water samples, level of cadmium in Seyyed Mahalleh was higher than standard level which is worrying due to accumulative effect of cadmium. In addition, level of cadmium in rice samples of Jouybar (Mahalleh Kola) and Seyyed Mahalleh was higher than standard level. Levels of chrome in all studied areas were lower than standard levels. Conclusion: Accumulative effects of heavy metals and their harmful effects on human societies could endanger food safety, therefore, more precautions are needed to reduce such effects.