Last week, the Environmental Protection Agency (EPA) proposed a new rule that would require dentists to dramatically reduce the amount of mercury and other heavy metals they are discharging into public water systems. The new rule would require dentists to drop their mercury emissions down to a level consistent with the use of the best technology available, metal amalgam separators, a practice already encouraged by the American Dental Association (ADA).
A “Common Sense Rule”
The EPA proposed the new rule under the authority granted by the Clean Water Act. According to the deputy assistant administrator for the EPA’s Office of Water, “This is a common sense rule that calls for capturing mercury at a relatively low cost before it is released into [public water systems].” The rule is expected to remove at least 8.8 tons of metal (half of it mercury) that would otherwise be discharged into the water.
Not only that, the rule is expected to reduce overall costs of oversight for this concern by $47 million and simplify the paperwork for dentists. Dentists would now only have to certify that they installed the amalgam separators in order to show the he is compliant with the new rule. Dental offices currently account for about half of the mercury that enters our public water systems and eventually ends up contaminating lakes and streams. And although the mercury may begin as elemental mercury, which has a relatively low toxicity, once in the water system, it can be changed into methylmercury, a highly deadly neurotoxin, which can then concentrate in fish and other lifeforms until they reach dangerous levels.
This is only proposed rule. The EPA will accept comments for 60 days, including at a hearing on November 10. Based on the comments received, the EPA will finalize the rule, which it expects to accomplish by September 2015.
A Deadly Metal
This new rule serves as a reminder that mercury is extremely toxic. With the high level of concern about adding mercury to the water supply, how can we still think it’s safe to add to our mouths, or keep it there, leaking mercury?