Elemental mercury is the primary component of dental amalgam. Mercury is a naturally occurring metal in the environment and can exist in liquid, gas or solid form when combined with other metals. Everyone is exposed to mercury through air, drinking water, soil and food. The concern is how much mercury exposure is too much before becoming mercury poisoning, and are mercury levels increasing as a result of interactions with other elements in the environment?
Mercury is released into the environment whenever a dentist removes an old amalgam filling from a cavity, or when excess amalgam is removed during the placement of a new filling. There is a concern that low levels of vapor can be inhaled and absorbed by the lungs even years after an amalgam filling is placed in a patient’s mouth, potentially causing long-term damage to the brain and kidneys. Due to the lack of scientific data surrounding this concern, little has been done over the years to limit the use and/or disposal of dental amalgam.
In 2009, the FDA issued a final rule that classified dental amalgam (dental amalgamator) as a Class II device accompanied by a document that designates special controls for dental amalgam. The Agency for Toxic Substances and Disease Registry (ATSDR) and the EPA have established mercury exposure levels aimed at protecting the most mercury-sensitive populations from the adverse effects of mercury vapor, namely pregnant women, developing fetuses and all children under 6 years old.
It is understood that a number of dental offices may already have an amalgam separator in place, whether to comply with existing state or local amalgam regulations, or because they voluntarily installed an amalgam separator. According to the new EPA ruling, dental offices with existing amalgam separators will not be penalized as long as the separator is certified to remove 95% of total mercury.
The EPA will not require existing separators that still have a remaining useful life to be retrofitted with a new separator, because of the additional costs incurred by dental facilities that proactively installed an amalgam separator ahead of the EPA’s proposed requirements, and because of the additional solid waste that would be generated by disposing of the existing separators.
As long as offices with existing separators continue to properly operate and maintain the separator and comply with BMPs and recordkeeping requirements, these offices will be deemed in compliance with the new ruling until ten years from the effective date of the final rule.