Cov hlau hnyav yog ib pawg ntawm cov kab mob uas suav nrog cov hlau thiab hlau xws li arsenic, cadmium, chromium, cobalt, tooj liab, hlau, lead, manganese, mercury, npib tsib xee, tin thiab zinc.Cov hlau ions paub tias yuav paug cov av, cov huab cua thiab cov dej thiab yog cov toxi ...
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