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Those silver mercury fillings whose vapors readily pass through cell membranes, across your blood-brain barrier, and into your central nervous system? The damage doesn’t stop there.

The US Environmental Protection Agency (EPA) recently cited studies showing that approximately
half of the mercury in the environment is there due to dental offices’ amalgam (i.e. silver filling) waste.

In fact, dental clinics are the main source of mercury discharges to public water treatment centers, according to the EPA, which estimates there are about 160,000 dentists in the US who use or remove amalgam and virtually all of them discharge their wastewater to water treatment centers.

In all, dentists discharge about 4.4 tons of mercury a year to such centers. The problem, of course, is that the mercury then settles into sewer systems or the biosolids and sewage sludge that are generated during water treatment.

What happens to the sludge? Some of it ends up in landfills, while other portions are incinerated (thereby polluting the air) or applied as agricultural fertilizer (polluting your food), or seep into waterways (polluting fish and wildlife).

Unfortunately, mercury is persistent and bioaccumulative once it reaches the environment. And when it is exposed to certain microorganisms in water, it can change into highly toxic methylmercury – the type that now contaminates most seafood.

Most Americans don’t realize that there is a simple solution that could drastically cut down on the environmental pollution caused by mercury waste, if only dentists would choose to use it.

EPA Proposes Rule Requiring Dentists to Use Amalgam Separators

The road to a federal rule mandating separators for American dentists has been long and circuitous.

The US is a federal system, so ideas generally start at the state level. A century ago, a distinguished Supreme Court Justice, Louis Brandeis, called the states “laboratories of democracy.”

Fourteen years ago, Michael Bender of the Mercury Policy Project launched a campaign to persuade state and local governments to mandate separators. He enlisted state-based environmental groups, plus national groups like Clean Water Action and the Natural Resources Defense Council.

The prototype for action was the city of Toronto, Canada, which cut the mercury in water by more than half by mandating separators. Over the decade of the 2000s, 12 states, most of them in the Northeast, mandated separators, as did many US cities, such as Duluth, Wichita, and San Francisco.