Nickel
Nickel
Nickel is a heavy metal, and it can be an important toxic chemical in the environment . Natural pollution by nickel is associated with soils that have a significant presence of a mineral known as serpentine. Serpentine-laced soils are toxic to nonadapted plants, and although the most significant toxic stressor is a large concentration of nickel, sometimes the presence of cobalt and/or chromium, along with high pH and an impoverished supply of nutrients also create a toxic environment. Serpentine sites often have a specialized flora dominated by nickel-tolerant species , many of which are endemic to such sites. Nickel pollution can occur through human influence as well—most often in the vicinity of nickel smelters or refineries. The best-known example of a nickel-polluted environment occurs around the town of Sudbury, Ontario , where smelting has been practiced for a century.