The EPA rule requiring mercury amalgam separators in dental offices has been revoked. This turnabout fascinates us. Mercury is, after all, a known neurotoxin with unique properties.
In fact, a 15th century a German sage marveled at its physical  properties,  saying,
This quicksilver is neither too hot, nor too cold, nor too moist, nor too dry, but it is a well-tempered mingling of all four.
Mercury is seductive.  Perhaps you can recall a fascination with the beads of a broken thermometer? How you marveled at the curious dry yet fluid metal as it escaped your grasp?
Mercury proves itself elusive to our intellectual grasp as well.  For even as scientific documentation justifies our fear about mercury’s toxic nature, it plays an intimate role in our daily lives. This shapeshifter has found its safe haven in the most intimate orifice our body, our mouths.
The Minamata tragedy and others like it capture the damage caused by exposure to environmental mercury. But a recounting of historical snapshots only frames part of the picture. There are tragedies we recognize, and tragedies we choose not to recognize. Intellectually, while we know mercury is toxic, many refuse to acknowledge the damage that mercury lodged in teeth poses. For as long as a mercury filling sits in a mouth, mercury vapors leach out, inches from our brain. It’s a silent and chronic toxin. Somehow, this pollution is still allowed in people’s bodies while agencies worldwide work to contain it in the environment.
According to a 1977 article in The Atlantic,
But even if stringent controls on all sources of mercury pollution were strictly enforced, many scientists suspect that mercury already in the water supply will remain a threat for years to come. The reason is that when “inorganic” mercury salts enter a lake or river, they sink to the bottom, where they are slowly converted by microbial action into the “organic” methyl mercury form which killed scores of Japanese twenty years ago and poisoned the Quebec Indians last year. Once converted to the organic methyl mercury form, the poisons move up the food chain from phytoplankton to fish to man. That could mean that microbes will be converting the 200,000 pounds of mercury now resting on the bottom of Lake St. Clair alone into methyl mercury for the next 5000 years. And the mercury now there cannot be easily removed, since dredging operations would disseminate it more widely. Verdict: The mercury crisis may be forgotten, but it is not over.
Documentation of mercury damage can also be elusive. Certainly, mass poisonings have caught our attention, but overall, we appear to be nation with short-term memory loss.
1953 to 1971 — Residents of Minamata, Japan suffered from mercury poisoning after eating fish contaminated by mercury waste products from a local factory. As of 2001, the poisoning has proved fatal to 1784 of its 2265 victims. In addition, children born to women who ate the contaminated fish were born with cerebral palsy and suffered from chorea, ataxia, tremors, seizures, and mental retardation.
1964 to 1965 – What happened in Niigata, Japan is referred to as the “second Minamata Disease.” With 702 “officially certified” victims to date, there are still 2,400 applicants going through the application process to certify them as victims of methylmercury released into wastewater from an industrial plant.
1969 — A New Mexico family of 10 suffered permanent neurological damage when a farmer and his family ate pork inadvertently fed with seed grain that had been treated with methylmercury fungicide.
1971 to 1972 – More than 6500 cases of mercury poisoning were reported, with at least 459 deaths, from consuming grain treated with methylmercury fungicide in Iraq. It’s important to note the death toll appears to have risen with the passing of time. Shortly after this incident, methylmercury used as a fungicide seed treatment was banned worldwide.
1989 – Despite treatment for exposure to dental mercury vapor,  four adult occupants in a home died after one of them tried to separate silver from dental amalgam by heating and melting it in a casting furnace in the basement. The mercury vapor went up the air ducts and circulated in the home where it was inhaled.
1996 – Dartmouth College chemistry professor Karen Wetterhahn spilled a small amount of dimethylmercury on her latex glove. Despite treatment, she died shortly after from mercury intoxication.
2008 – Actor Jeremy Piven was diagnosed with mercury poisoning. Piven at sushi twice a day for 20 years and may have consumed mercury in herbal remedies.
2008 – Tony Winnett died after inhaling mercury vapors while using liquid mercury to separate gold from the alloy, retrieving the gold from computer parts.
In all its forms, mercury is toxic. Mercury is never inert. In the US mercury used in dental amalgam is dumped into wastewater treatment centers at the rate of 4.4 tons per year. This mercury sewage bioaccumulates in the fish we eat. In the US, mercury contaminated fish ushers a constant warning to pregnant women and young children. The set of scientific facts that generated a warning in the US were evaluated in the EU, where the risks were recognized and a ban was issued.
In the US, we’re still debating on how to keep mercury sludge out of wastewater facilities. Even if you never thought of yourself as an activist, you could help keep 4.4 tons of mercury out of our waterways. Read this.  Wherever you go for dental services, ask them if they use a mercury amalgam separator. The question is a simple act that will ensure dentists everywhere hear what’s important to you. Your question gives them an opportunity to not only do the right thing, but for the right thing to matter.