“Heavy metals” are those with high density. They are often implicated in human poisoning, particularly lead, mercury, arsenic and cadmium.
Some heavy metals, such as zinc, copper and chromium, are required by the body in small amounts, but large doses are toxic.
Environmental sources of heavy metals include air emissions from coal burning plants, smelters and waste incinerators, and wastes from mining and industry. We can be exposed to heavy metals through air pollution, and contaminated food, water and soil.
Health effects include childhood developmental problems, cancers, organ damage and autoimmune condition. Heavy metal poisoning may be fatal in severe cases.
- Olivia Rose-Innes, EnviroHealth Editor, Health24, April 2012