Between 270 and 341 tonnes of mercury are consumed globally for use in amalgam each year. Accounting for at least 10% of global mercury consumption, amalgam is among the largest consumer uses of mercury in the world.
Pathways to the environment
Dental mercury enters the environment via many different pathways. For example, dental mercury pollutes:
- air via human cremation, sewage sludge and waste incineration, and dental clinic emissions
- water via human waste disposal and dental clinic releases
- land via landfills, human burials, and fertilizers
Environmental health risks
After amalgam enters the environment, certain microorganisms can change its elemental mercury into methylmercury, a highly toxic form of mercury that builds up in fish, shellfish, and people that eat fish. Methylmercury can damage children’s developing brains and nervous systems even before they are born.
After environmental costs are taken into account, amalgam is significantly more expensive than the mercury-free alternatives. According to the 2012 report The Real Cost of Dental Mercury, an amalgam filling can cost up to $87 (USD) more than an equivalent mercury-free composite filling once the full lifecycle costs of each filling is considered.