Soils contaminated with zinc from mining, refining, or fertilizing with zinc-bearing sludge can consist of various grams of zinc per kilogram of dry soil. Levels of zinc in surplus of 500 ppm in soil interfere with the ability of crops to absorb other necessary metals, which include iron and manganese. https://zincsulfide39405.creacionblog.com/28004503/zinc-sulfide-options