Heavy metals pose a serious threat to our health. Among the World Health Organizations (WHO) Top 10 chemicals of major health concerns, four of them are metal or metalloid: arsenic, cadmium, lead and mercury. Because of their toxicity, they are also listed in the National Primary Drinking Water Regulations.
Long-term exposure to inorganic arsenic causes skin pigmentation change and lesions and eventually can lead to cancer.
Cadmium targets mainly the kidneys to cause renal diseases and stays in our body from 10 to 35 years.
Lead has multiple targets in our body and is deposited mainly in bones and teeth. Children absorb four to five times as much lead as adults; children who ingest lead may suffer from neural diseases and anemia.
Both elemental mercury and methyl mercury are toxic. Mercury stays in the air for one year but can be stable in water sediments for millions of years. Long term exposure to mercury in drinking water can lead to irritability, nervousness, changes in vision or hearing, and difficulties with memory. It can also lead to kidney damage.
Another heavy metal of concern is aluminum.
Most of our daily aluminum intake is from food and water. Aluminum in water is in a form that is more readily absorbed by the body, and very high aluminum levels in water can be of concern. Aluminum is used in water treatment to remove disease-causing microorganisms and other drinking water impurities that can affect your health.