Soils contaminated with zinc from mining, refining, or fertilizing with zinc-bearing sludge can contain quite a few grams of zinc per kilogram of dry soil. Amounts of zinc in excess of 500 ppm in soil interfere with the power of plants to absorb other critical metals, including iron and manganese. https://keegansyddb.idblogmaker.com/27741117/how-much-you-need-to-expect-you-ll-pay-for-a-good-infrared-zinc-sulfide