Growing scientific evidence
suggests the most widespread industrial contaminant
in drinking water -- a solvent used in adhesives,
paint and spot removers -- can cause cancer in
people.
The
National Academy of Sciences reported that a lot
more is known about the cancer risks and other
health hazards from exposure to trichloroethylene
than there was five years ago when the Environmental
Protection Agency took steps to regulate it more
strictly.
"Armed
with the results from the NAS review, EPA will
aggressively move forward" on a new risk assessment
of TCE, spokeswoman Jennifer Wood said. "EPA will
determine whether or not to address the drinking
water standard once the risk assessment is complete."
TCE, which is also widely
used to remove grease from metal parts in airplanes
and to clean fuel lines at missile sites, is known
to cause cancer in some laboratory animals. EPA
was blocked from elevating its assessment of the
chemical's risks in people by the Defense Department,
Energy Department and NASA, all of which have
sites polluted with it.
TCE
is a colorless liquid that evaporates at room
temperatures and has a somewhat sweet odor and
taste. It is one of the most common pollutants
found in the air, soil and water at U.S. military
bases. Until the mid-1970s, it also was used as
a surgical anesthetic.
TCE
also has been found at about 60 percent of the
nation's worst contaminated sites in the Superfund
cleanup program, the academy said.
Its 379-page report recommends that EPA revise
its assessment of TCE's risks using "currently
available data" so no more time is
wasted.
That's a step that could lead to stricter regulations.
EPA currently requires limiting TCE to no more
than 5 parts per billion parts of drinking water.
A stricter regulation could, in turn, force the
government to require more thorough cleanups at
military and other sites.
A committee of academy experts said "a large
body of epidemiologic data is available"
on TCE showing the chemical is a possible cause
of kidney cancer, reproductive and developmental
damage, impaired neurological function and autoimmune
disease.
"The committee found that the evidence on
carcinogenic risk and other health hazards from
exposure to trichloroethylene has strengthened
since 2001," the report said. "Hundreds
of waste sites are contaminated with trichloroethylene,
and it is well documented that individuals in
many communities are exposed to the chemical,
with associated health risks."
In 2001, EPA issued a draft document saying the
risks of TCE causing cancer in humans were higher
than previously thought. But that pronouncement
was dropped after other federal agencies accused
EPA of inflating the risks.