Once mercury is released into air, soil, and/or water, it can pose a threat to wildlife for centuries. Dental amalgam mercury pollution is a major contributor to this danger because amalgam fillings, also referred to as silver fillings, are made of about 50% mercury. In addition to posing health risks to humans, the fact that dental amalgam mercury pollution harms the environment has been established in scientific literature. Moreover, the United Nations Environment Programme (UNEP)’s Minamata Convention on Mercury, a global treaty to protect human health and the environment from the adverse effects of mercury, includes initiatives to phase-down the use of dental mercury.
Dental Amalgam Mercury Pollution Harms the Environment in a Number of Ways
- Wastewater from dental offices is the first way that dental amalgam mercury pollution harms the environment. When dental amalgam fillings are placed, cleaned, or removed, mercury can be released into the wastewater from dental offices. The impact is substantial: Dental amalgam has been recognized as the leading end-use sector of mercury in the United States, and dental offices have been recognized as the main source of mercury discharges to publicly-owned treatment works (POTWs). The dental mercury sent to POTWs can, in turn, be re-released to the atmosphere from incineration and can also contaminate soil with mercury if the sludge is used as fertilizer.
- Human waste is a second way that dental amalgam mercury pollution harms the environment. Patients with amalgam fillings excrete over ten times more mercury in their feces than those without mercury fillings. The IAOMT has estimated that in the U.S. alone, this amounts to over 8 tons of mercury flushed out to sewers, streams, and lakes per year.
- Cremation and burial are a third way that dental amalgam mercury pollution harms the environment. If someone with mercury fillings is cremated, the mercury from the fillings is released into the air, and this results in over 3 tons of mercury emitted to the environment per year. Burying an individual with amalgam fillings means that the mercury is re-deposited directly into soil.
- Mercury vapor is a fourth way that dental amalgam mercury pollution harms the environment. Mercury vapor has been found in air inside and outside of dental offices at high levels, and it is also continuously emitted from dental amalgam fillings.
Reducing Harms to the Environment from Dental Amalgam Mercury Pollution
Amalgam separators, which are now required by the U.S. Environmental Protection Agency, can reduce the amount of mercury discharge in wastewater from dental offices. However, it would now be helpful to enforce maintenance requirements for amalgam separators. It should also be remembered that amalgam separators only contribute to reducing dental mercury in wastewater and not the additional burdens on the environment and human health.
Overall, the best way to reduce harms from dental amalgam mercury pollution to the environment is for dentists to stop using dental amalgam, as viable alternatives exist, and for dentists to use protective measures to mitigate mercury releases during amalgam removal.
This video shows how dental amalgam harms the environment with mercury pollution.