> THE NATION
> Dentists Biggest Mercury Polluters, New Study Finds
> Health: The metal is widely used in fillings and ends up in the nation's
> waste
> water.

> By ELIZABETH SHOGREN
> TIMES STAFF WRITER June 6, 2002 WASHINGTON - Coal-fired power plants are
> notorious for being the biggest source of mercury pollution in the air.
> But
> now, new attention is being directed at another, much less known source of
> mercury contamination in water--dentists. A new report shows that dentists
> are
> the largest single source of mercury pollution in waste water funneled
> into the
> nation's treatment plants. Mercury is a potent toxin that can damage the
> human
> brain, spinal cord, kidney and liver, and is especially dangerous for
> unborn
> children. While many other sources of mercury pollution have drastically
> cut
> their use of the heavy metal, dentists continue to use it widely in
> fillings.
> "Pretty much all the mercury they're using gets released into the
> environment.
> Why aren't they doing more to reduce that use?" said Michael Bender,
> director
> of the Mercury Policy Project, a foundation-funded group that was one of
> the
> authors of the study. Power plants emit mercury into the air and it falls
> into
> streams and rivers. Many dentists flush it down their drains and it goes
> directly into waste-water treatment plants, which do not effectively
> filter it
> from the water. In a statement responding to the report, the American
> Dental
> Assn. said it was aware that some particles from fillings end up in waste
> water, and it urges dentists to follow proper procedures for handling and
> recycling the composite used for fillings, which they refer to as
> "amalgam."
> But the association argued that the mercury from their fillings remains in
> a
> form that is not harmful to humans. "However, a 1996 study found that when
> amalgam particles were subjected to simulated waste-water treatment
> processes,
> no soluble mercury was detected, even at a concentration of 1 part per
> billion," according to the statement. The group stressed that it was
> currently
> implementing a new plan to address the problem. The new report's authors
> said
> that dentists, through voluntary or mandatory measures, should trap their
> waste
> mercury before it flows into plumbing fixtures that have been contaminated
> with
> mercury for years. The report referred to a 2001 study by the Assn. of
> Metropolitan Sewerage Agencies that evaluated seven major municipal
> waste-water
> treatment plants and determined that dental uses were "by far" the
> greatest
> contributors to the mercury reaching their facilities. They were
> responsible
> for 40% of the load, three times more than the next largest contributor.
> Several other countries regulate releases of dental mercury. In Canada, a
> new
> standard requires dentists to trap the pieces of filling before they go
> down
> the drain. The goal is to reduce releases by 95% by 2005. In May, the New
> Hampshire Legislature became the first in the nation to pass legislation
> governing disposal methods for dental mercury. The California Assembly
> considered a measure to phase out the use of mercury in fillings but did
> not
> adopt it. The report suggests that mercury in dentistry has become the
> exception while other major users of mercury have changed their practices.
> In
> 1985 dental facilities used 3% of all the mercury used nationwide. Last
> year,
> although dentists used less mercury, their use accounted for 20% of all
> uses.
> Only two other industries--wiring devices and switches and
> chloralkali--used
> more. Gina Solomon, a physician who focuses on the health effects of
> mercury
> for the Natural Resources Defense Council, said that there was still
> controversy about whether the fillings put dental patients at risk. And
> she
> stressed that those who have such fillings should not get them removed,
> because
> taking them out heightens the chance of exposure. However, she said the
> science
> is clear that the mercury that goes down the drain can end up in the food
> chain. "There is scientific consensus that mercury that ends up in the
> waste
> water and water bodies will accumulate in the fish and pose a direct human
> health problem to people who eat the fish; that is uncontroversial and is
> something that can be fixed," Solomon said. If you want other stories on
> this
> topic, search the Archives at www.latimes.com/archive. For information
> about
> reprinting this article, go to www.lats.com/rights. Copyright 2002 Los
> Angeles
> Times