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People living
at polluted sites nationwide could be exposed to the toxin trichloroethylene,
or TCE, at levels higher than the Environmental Protection Agency identified as
a health concern in 2001, because the EPA never set new cleanup standards based
on its study.
The health-risk analysis that identified the danger TCE posed to those who breathe
even minute amounts was never translated into EPA policy, despite the recommendation
of its own Science Advisory Board. At the prompting of industry and other federal
agencies, the EPA has subjected the analysis to a review by the National Academy
of Sciences.
That review will take more than a year, leaving those who live at polluted sites
and the agencies responsible for remedying them using cleanup guidelines for the
ubiquitous solvent that vary from state to state, and even within the boundaries
of one town -- East Fishkill in Dutchess County.
Problem not new Environmental
and health agencies have been grappling with vapors that seep in from polluted
groundwater into homes since 1990. If
the EPA had set regulations based on its draft health analysis, it would have
put national cleanup guidelines between 0.017 to 1.7 micrograms of TCE per cubic
liter of air. The EPA can detect TCE at levels of 0.38 and higher. In
East Fishkill, the EPA has committed to removing all TCE vapors it can detect
in the Hopewell Precision neighborhood, where groundwater is polluted with TCE.
EPA spokesman James Haklar described this as a ''pro-active'' approach, determined
by aspects specific to that site, that will address homes where there is a ''potential
impact.'' It also ultimately saves money because it will reduce long-term monitoring
costs.
In the same town, a few miles to the south, the EPA could permit TCE vapors to
remain in homes in the Shenandoah neighborhood, as long as they don't exceed New
York's guideline of 5 micrograms per cubic liter -- about 13 times higher than
the smallest detectable concentration.
Vapors of TCE and/or a related chemical have been detected beneath 14 homes there,
and the EPA plans to test inside homes before the end of winter. The
apparent discrepancy is based on conditions specific to the two sites, including
that TCE is the main contaminant at the Hopewell Precision site, but a secondary
contaminant in the Shenandoah neighborhood, Haklar said. Some
residents, however, are outraged the EPA won't commit to cleaning their air as
much as the agency will in their neighbors' homes. ''It's
not a case that the danger is not there. It's more a case of whom are we protecting,''
said Denis Callinan, who lives in Shenandoah. ''It's obvious we are protecting
the federal government because they are one of the worst polluters ... and we
are definitely protecting major industry.'' The
discrepancies only grow with the miles.
In Endicott, about 180 miles away, New York and IBM Corp. are using the state's
guidelines -- though residents there have been outraged since learning of the
EPA's goal at the Hopewell Precision site in East Fishkill. Groundwater there
is polluted with TCE from an old IBM facility and vapors have seeped into hundreds
of homes.
''It is ludicrous to me that there are different standards,'' said Betty Hicks,
whose home in Hopewell Precision is being ventilated to reduce vapors. ''People
in Appalachia should die, and people in Scarsdale shouldn't die? It's ridiculous.''
State and federal elected officials have called for clearer, national standards.
National standards lacking With
the EPA's health-risk analysis in limbo, there are no national standards that
dictate when the EPA should take action to clean a site, nor are there national
guidelines for how thoroughly sites should be cleaned.
The EPA uses a variety of guidelines, which can vary among the agency's nine regional
offices, to determine which sites need to be cleaned, and to what extent. ''EPA
is currently evaluating a number of interim approaches for screening levels while
awaiting a final TCE risk assessment. Final clean up standards are determined,
as always, on a site-specific basis,'' Henry Longest II, acting administrator
for EPA's Office of Research and Development, wrote to U.S. Rep. Diana DeGette,
D-Colo., in December, after she requested the EPA finalize its 2001 analysis.
TCE
is one of several common halogenated solvents that were used for decades to clean
metal parts. Demand dropped in the mid-1980s as health concerns prompted new regulations,
but TCE production rebounded in the 1990s after similar chemicals were banned
for depleting the Earth's protective ozone layer.
Manufactured by the Dow Chemical Company and PPG Industries Inc., TCE's main use
now is as a precursor in the manufacture of refrigerants. North America used about
220 million pounds of TCE last year, according to the Halogenated Solvents Industry
Alliance. TCE
is nearly ubiquitous -- present in nearly 60 percent of the nation's 1,430 Superfund
sites, and in the air in most urban environments. It vaporizes easily, and can
seep from polluted groundwater through soil and into homes -- posing a risk not
only to those who drink tainted well water, but also those who breathe the air
in their homes. Three
and a half years ago, the EPA released a draft health-risk assessment that weighed
the latest scientific evidence about the toxicity of TCE. Following recent National
Research Council and presidential guidelines, the analysis was the EPA's first
to evaluate the risk the chemical posed to children, and the risk posed by cumulative
exposure to other contaminants.
The results were sobering:
- TCE is far more toxic than thought -- ''highly likely'' to cause cancer and
linked to a variety of toxic effects on the nervous, immune, reproductive and
other body systems. -
Breathing TCE was identified as a potent risk, even at very small concentrations.
The EPA normally sets cleanup standards for polluted sites based on risk analyses.
The
EPA sets its standards to reduce exposure to the point where no more than one
in 10,000 adults would be expected to get cancer if a 150-pound adult was exposed
for a lifetime -- 24 hours a day for 30 years.
In this case, TCE cleanup standards for contaminated air would have been so low,
the most sensitive instruments could not always detect harmful concentrations.
- Some of TCE's toxic effects are likely to be greater on children and adults
with certain diseases, including diabetes.
- Effects are likely to be exacerbated by exposure to other chemicals, including
alcohol and other chlorinated solvents.
Multiple contaminants found It's
not uncommon to have multiple contaminants at sites, and that's the case in both
East Fishkill neighborhoods
Shenandoah is primarily polluted with tetrachloroethylene, or PCE, which was allegedly
used to cleanse microchip racks by an IBM Corp. contractor in the 1960s and 1970s.
In groundwater, PCE degrades into TCE.
The Hopewell Precision site has the solvent trichloroethane, or TCA, in the water
as well as TCE. The EPA believes a metal cabinet manufacturer, Hopewell Precision,
used both chemicals to cleanse metal parts.
When the body metabolizes any of the three chemicals -- TCE, PCE or TCA -- the
same substance, trichloroacetic acid, is formed, though at different rates for
each chemical. Trichloroacetic acid can also form as a byproduct of chlorinating
drinking water. Trichloroacetic
acid is the metabolite associated with TCE that is most analyzed for its potential
to cause cancer. The EPA's 2001 draft analysis of TCE health risks identified
the cumulative exposure to different chemicals as a concern, in part, because
of the way they interact when the body metabolizes them.
For Debra and David Hall, that raises questions about the many homes in the Hopewell
Precision neighborhood that have detectable levels of TCE and/or TCA, but have
not had water filters or ventilation systems installed. The
couple is concerned about health problems they've heard about among people in
the neighborhood -- birth defects and cancers, including of the liver and kidney.
David Hall's liver showed unusual enzyme activity, similar to what might be seen
in an alcoholic's damaged liver, his doctor told him, yet he has only a handful
of drinks every year. They also had two young parakeets die from liver tumors.
''I go every year for the physical. Nothing was ever detected until we moved into
this house, and then once they started ventilating, the numbers started to drop,''
David Hall said.
''I really believe it had something to do with it,'' Debra said of the contamination.
''They say you can't prove it, but that's scary.'' No
homes in their neighborhood have been outfitted with water filters for TCA, because
it did not exceed the federal drinking water standard. New York has installed
filters on 14 of the 100 homes where TCA was detected because those 14 exceeded
the state's standard. No homes have been ventilated to reduce TCA fumes. IBM
installs filters
In the Shenandoah neighborhood, IBM has installed water filters even in homes
that show no contamination, but are near homes that have contaminated water. In
the Hopewell Precision neighborhood, however, filters are only installed in homes
that have concentrations of either chemical that exceed a state or federal standard.
Because
the EPA's 2001 TCE health-risk analysis is still a draft, any cumulative risk
posed by multiple contaminants is not considered when the EPA sets cleanup goals
at polluted sites. ''It's
something that is on the radar of ORD,'' Haklar said, referring to the Office
of Research and Development, ''but at this point it doesn't enter decisions.''
Industry
groups and government agencies questioned the scientific basis for the EPA's risk
analysis. Responding
to their concerns, and questions raised by its Science Advisory Board, the EPA
joined with the Department of Defense, the Department of Energy and NASA to commission
the National Academy of Sciences review. The EPA also convened a symposium a year
ago to hear about recently published research.
The National Academy of Sciences review should help settle controversy about the
importance of trichloroacetic acid as a human carcinogen, among other issues that
led to the EPA's ''conservative'' risk assessment, said Paul Dugard, science director
for the Halogenated Solvents Industry Alliance. The group represents companies
that manufacture, distribute and use TCE, PCE and other solvents.
Dugard said occupational exposure studies had not identified clear links to health
problems -- though some are cited in the EPA's analysis -- and people with polluted
water or air in their homes are exposed to far smaller concentrations than workers
were. He also questioned the conclusion humans would have the same health problems
identified in lab rats and mice exposed to TCE.
''Most scientists without a green activist edge, if you like, would see the draft
report as being extremely conservative in its treatment,'' Dugard said. ''It pushes
the acceptable levels down very low. For most people, that's not how they see
trichloroethylene. It was widely used and still is used. It's not a super toxin
by any means.'' The
Department of Defense also wanted to see the National Academy of Sciences review
the EPA's work.
''We welcome the NAS coming into it,'' Defense Department spokesman Glenn Flood
said. ''We want a body like that to be able to stand back from both agencies and
say, 'This is what we've got.' ''
Both Dugard and Jennifer Sass, a scientist for the Natural Resources Defense Council,
said the panel assembled by the National Academy of Sciences seems fair and qualified.
Critics: Cost is issue
That hasn't stopped critics from charging the departments of Defense and Energy
are less concerned about sound science than saving money. The federal government
is responsible for at least 46 Superfund sites with TCE, many of them at Air Force
bases, according to an EPA database. More strict cleanup standards would drive
up costs. The
costs can vary, but testing at individual homes often costs $1,000, and ventilation
systems can cost between $1,500 to $5,000, according to New York estimates.
''The military has been complaining about this all along. They complained enough
that they got it delayed,'' Sass said. ''We know that it's a common, widespread
water pollutant. And we know it's very toxic.'' This
isn't the first EPA risk analysis to get caught in limbo amid controversy, Sass
said. The EPA's cancer risk guidelines have yet to be updated.
Based on the agency's 1999 proposed guidelines, TCE would be considered ''highly
likely'' to cause cancer. Under the ''current'' 1986 guidelines, TCE is considered
a ''probable human carcinogen.''
It will be some time before the EPA finishes its TCE health risk assessment and
sets national standards. The National Academy of Sciences panel will convene March
23 and 24. When it completes its 15-month study, the EPA anticipates incorporating
it into its health-risk analysis along with recently published research. It will
subject the analysis to scientific peer review and public comment. ''We
believe this process will not only address the EPA (Science Advisory Board's)
comments, but also provide a risk assessment of the highest quality and scientific
credibility,'' the EPA's Longest wrote in December.
New York's Department of Environmental Conservation has identified more than 400
sites statewide that have the potential for vapor intrusion problems with TCE
and other chlorinated volatile organic compounds. It is working on a draft policy
to test and, if necessary, clean up these sites, most of which had been considered
safe until vapor intrusion was identified as a health risk. The
Department of Health is also convening a scientific panel to review its guidelines
for TCE in air.
Until there are clear guidelines, people in Endicott, Shenandoah and around the
country will continue to worry about their health and know that the longer they
are exposed to chemicals -- if they are indeed at unsafe levels -- the greater
their risk of developing health problems. ''It
is, to me, a tragedy,'' said Lenny Seigel, who has fought for strict cleanup standards
in his Mount View, Calif., neighborhood and around the country. ''People are breathing
this stuff, so it was a victory for the polluters.''
Copyright © 2005, Poughkeepsie Journal
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