U.S. Water News Online
DANBURY, Conn. -- For more than 150 years, mills in the hat
capital of the world shipped their toppers out to stores, and dumped
their mercury into the river.
Danbury's hatters used a solution of mercury and nitric acid to
convert animal fur into felt for hats. The use of mercury in
hatmaking was banned in the 1940s, and the factories have long been
still. But levels of the toxin are high in Danbury and some 50 miles
downriver, and some are worried about safety.
``These levels are insane,'' said Wesleyan University scientist
Johan Varekamp, who has run tests for mercury in Danbury and on the
banks of the Housatonic River and one of its tributaries, the Still
Mercury, which damages brain tissue, is especially a threat to
developing fetuses and young children. For that reason, health
advisories on the consumption of tainted fish are aimed at children
under 6 and pregnant women first.
Mercury also can cause skin irritations and kidney and muscle
The state standard for requiring a cleanup of mercury in
residential areas is 20,000 parts per billion. Natural concentrations
of mercury in soils are usually 100 ppb or less. The levels of
mercury in soil attributed to air pollution usually don't exceed 400
to 600 ppb.
Varekemp found mercury levels as high as 67,000 ppb on the grounds
of a former hat factory, and 25,000 ppb in a playground across the
street. He also found high levels around the mouth of the Housatonic
and in fish that live in the river.
Although it's difficult for health experts to say with certainty
just how big a health risk the Danbury findings pose, they agree it's
not wise to take chances with such a potent toxin, which particularly
affects pregnant women and young children.
``Anytime you find mercury in an old industrial site it's a red
flag. It's a potentially serious problem,'' said David Brown, a
Westport toxicologist who has worked on public health issues,
including mercury, for the U.S. Agency for Toxic Substances and
Disease Registry, part of the Centers for Disease Control and
The last hat mill in Danbury, the old Mallory factory, closed in
the early 1980s, and was demolished in 2000. A 1999 environmental
study done for the city showed elevated levels of mercury and other
pollutants in the soil around the property, and concluded that it
would need to be cleaned up.
``We're now in the process of trying to remediate and clean up the
property,'' said Jack Kozuchowski, coordinator of Danbury's
environmental and occupational health services.
The city is trying to market the property to prospective
developers and is hoping to get a state grant or loan to pay for the
The federal Environmental Protection Agency awarded the city a
$50,000 grant in May to help clean up another contaminated site,
Barnum Court, using a technique called phytoremediation. The
technique uses plants to clean the soil by drawing the mercury into
their stalks and leaves as they grow.
Kozuchowski and Varekamp are working on a pamphlet that will warn
residents for the first time about possible mercury exposure in and
around the Still River, and hope to distribute it later this year.
Kozuchowski's health office is also planning to post advisories
along the river to warn people to limit their consumption of fish.
Return to the
U.S. Water News Archives page
Return to the U.S. Water
Use a comma to separate e-mail addresses:
Hi, I thought you might like to read this article.