From: Robina Suwol
Date: 21 Feb 2004
Time: 15:32:21
Remote Name: 68.116.132.127
Sat, 14 Feb 2004
LATE LESSONS FROM PRESSURE-TREATED WOOD - Part1
by Sandra Steingraber, Ph.D.*
Within the European Union, the European Environment Agency (EEA) is charged with
providing information for environmental decision-making, especially in
situations where the science is uncertain. Three years ago, this agency
published a remarkable book, Late Lessons from Early Warnings: The Precautionary
Principle 1896-2000.[1]
This report explores how scientific knowledge about possible environmental
health threats is gathered and used to make public
decisions. Organized around twelve case studies -- ranging from radiation to mad
cow disease -- the various chapters benefit from
hindsight as they examine the ways in which the first warnings about these
now-known hazards were sometimes wisely heeded but more often foolishly ignored,
cynically scorned, or researched for decades until the evidence for harm became
so egregious that something had to be done. In some cases, the actions finally
taken to redress the problem were so late in coming that "pipelines of
unstoppable consequences" were already set in place.
The earliest warnings on the dangers of asbestos, for example, came from a
British factory inspector, Lucy Deane, who, in 1898, correctly documented the
"evil" effects of inhaling its tiny, glass-like fibers. One hundred years later,
the United Kingdom finally banned white asbestos. The current death rate in
England from asbestos-related disease is 3,000 people per year.[2] An early
warning unheeded. Last month in Brussels, I had the privilege of hearing David
Gee, the report's principle author, address the European Parliament. Why, he
asked, do so many environmental health disasters fall victim to wait-and-see
attitudes? What lessons can be brought from the past to the problems of the
present? In an upcoming issue of Rachel's Environment & Health News, we will
look more closely at the warnings and lessons in Gee's report (which is soon to
be re-released with additional case
studies [3]) and how it is inspiring the implementation of the precautionary
principle in Europe.
Here, we apply Gee's historical approach to an environmental health problem that
continues to haunt back yards and playgrounds throughout the United States:
pressure-treated wood. The name itself is a euphemism. What pressure-treated
wood is actually
treated with is a mixture of pesticides called chromated copper arsenate (CCA).
Pressure-treated lumber is made by placing a freshly milled board inside a
vacuum chamber and sucking from its fibers all water and air. Then, under high
pressure, copper, chromium, and arsenic are forced into the now empty cells.[4]
Pressure treatment is to wood what embalming is to humans.
As of January 1, 2004, after seventy years of production, the manufacture of
pressure-treated (CCA) wood for residential use has ended in the United
States.[5] It turns out that the arsenic in pressure-treated wood rubs off on
the hands of those who touch it. When those who touch it are children, their
risk of developing lung and bladder cancer are significantly raised.[6] Young
children at play put their hands in their mouth an average of 16 times an
hour[7].
CCA is 22 percent pure arsenic by weight. Arsenic is a known human
carcinogen.[8] A recall of all the swing sets, picnic tables, decks, and fences
already constructed from this lumber is, however, not part of the decision to
cancel the registration of CCA. And with 90 percent of all outdoor wooden
structures in the United States made of pressure-treated wood, each with an
expected life span of twenty years or more, a "pipeline of unstoppable
consequences" may, even now, be well under construction.
Weathered lumber leaches as much -- or more -- arsenic than newly milled
boards.[10] Arsenic, like all metals, is absolutely persistent in the
environment. It does not biodegrade. It does not go away. Pressure-treated wood
is a case study not included in the EEA's "Late Lessons" report -- but it could
be.
The story begins in 1933 when an Indian engineer, Sonti Kamesam, made a
discovery that saved the lives of countless coal miners: injected into wood,
arsenic and copper prevent timber beams from rotting. Arsenic, a time-honored
poison, kills wood-eating insects. Copper kills fungus. Kamesam's special trick
was to add chromium to his formula, thereby binding the two toxic metals to the
wood fibers.[11] The result was stronger roofs in the damp underground tunnels
through which coal is extracted. One can imagine that the last thing a coal
miner wants to see in the beams above his head is dry rot or termites.
Kamesam's invention not only extended the life expectancy of miners in India, it
saved money and trees. His work quickly attracted attention in the United
States. A patent was granted in 1938.[12] Meanwhile, researchers in Mississippi
pounded wooden stakes treated with copper chromium arsenate (CCA) into fields
that swarmed with termites. Months later, they were still standing.
In 1950, a highly impressed Bell Telephone applied for permission to use CCAwood
for telephone poles.[13] At this time, arsenic was known to be an acute poison,
but its ability to cause cancer at low doses was notgenerally understood. For
the next two decades, CCA wood remained a specialty product. Porches, fences,
docks, and boardwalks continued to be constructed out
of tree species that are naturally rot-resistant, such as cedar, redwood,
cypress, or fir. When the structures from these woods finally collapsed -- or
some unlucky soul fell through the floorboards -- they were simply rebuilt.
Then, in the 1970s, the price of wood soared. Cheap, plantation-grown southern
pine became the homeowner's construction material of choice.[14] And it could be
made to repel insects and dry rot with a pesticidal formulation originally
intended to
prevent mines from caving in.
Early concerns about pressure-treated wood surfaced during the 1970s as
pressure-treated wood found its way into picnic tables, gazebos, landscaping
timbers, and California-style decks on the backs of suburban homes.[15] No one
eats, barbecues, or sunbathes on the pesticide-soaked rafters of mine tunnels,
but the back yard deck was specifically designed with such activities in mind.
Even more ominous was the growing use of pressure-treated wood in children's
playgrounds. Wooden, castle-style play structures, complete with towers and
swaying suspension bridges, became the rage.
In 1978, the U.S. Environmental Protection Agency began a special review. Ten
years and many delays later, the EPA decided to reregister CCA as a pesticide
without restrictions on the use of the treated wood -- in spite of the fact that
CCA exceeded the agency's risk criteria for carcinogenicity, and all other uses
for arsenical pesticides were canceled.[16] At this point, almost no one in the
general public was aware that pressure-treated wood contained pesticides. Nor
that those sawing or sanding the wood should wear goggles and gloves. Nor that
work clothing that comes in contact with the wood should be washed separately.
Nor that food should never touch it.
The EPA did recommend that pressure-treated wood sold directly to consumers via
lumber yards and home improvement centers bear warning labels. The timber
industry balked, proposing instead that retail stores should distribute fact
sheets to educate buyers about the wood's potential hazards. The government
agreed. Few retailers complied with this decision. The government did little to
enforce it.[17]
Warnings continued to trickle in throughout the 1980s. Workers in wood treatment
plants were found to have elevated levels of arsenic in their
urine. A government employee became completely disabled after building picnic
tables in an unventilated shop. Eight members of a rural Wisconsin family fell
ill with a mysterious neurological disease that turned out to be arsenic
poisoning caused by burning pressure-treated lumber in the wood stove.[18]
In 1990, the Consumer Product Safety Commission released the results of its
investigation into children's exposure to CCA from playing on pressure-treated
wood playground equipment. The study did conclude that contact with such play
structures increases children's exposure to arsenic, but the only health
endpoint considered was skin cancer and the risks were considered insufficient
for a ban.[19]
Then, in the 1990s, the scientific case against pressure-treated wood became
more damning. The National Research Council reported that arsenic exposure
through drinking water was linked to lung and bladder cancers and could exert
its carcinogenic powers at much lower levels of exposure than previously
believed. Children, whose livers metabolize arsenic more slowly, were shown to
be at particular risk.[20] Other discoveries followed: at very low levels,
arsenic interferes with a family of hormones called glucocorticoids, possibly
raising the risk fordiabetes.[21]
Meanwhile, in 1996, far from the lab bench, a Connecticut chemist, David
Stilwell, began crawling around back yard decks throughout New England. A year
later, he reported that the soil under and around pressure-treated structures
contained concentrations of arsenic far in excess of background levels, and in
some cases, far in excess of the clean-up standards for Superfund sites
More than sixty years after Kamesam's humanitarian invention, Stilwell
discovered that chromium does not serve as such an effective binding agentafter
all. Eventually, the arsenic and copper leach out. Especially if thewoodis
rained on.[22]
Still other researchers began to consider if inhalation of arsenic-contaminated
dust -- as when children play in the dirt beneath
decks and play structures -- might be a route of exposure as significant as
ingestion by hand-to-mouth transfer.[23]
In light of these discoveries, two environmental organizations, Environmental
Working Group (EWG) and Healthy Building Network (HBN), teamed up to conduct
their own investigation. Analyzing data from 180 different wood samples, these
researchers concluded that playing on pressure-treated wood is a greater source
of arsenic exposure for children than drinking arsenic-contaminated drinking
water.[24] (At the time this report was released, spring 2001, the Bush
administration had just delayed the implementation of new, tighter drinking
water standards for arsenic -- to the outrage of many.)
EWG and HBN then petitioned the Consumer Product Safety Commission for an
immediate ban on the use of CCA wood in play equipment and a recall onexisting
structures.[25] The Commission responded by launching a new risk assessment. As
did the EPA. Also in spring 2001, an investigative journalist in Florida, Julie
Hauserman of the St. Petersburg Times, wrote a Sunday story, "The Poison in Your
Backyard," that brought the issue to the public at last.[26] The result of
months of investigation, Hauserman collected soil beneath playgrounds in a
five-county area and sent it to labs for testing.
Working closely with scientists at the University of Florida and the University
of Miami, she also looked at what happens to the arsenic in pressure-treated
wood dumped in landfills -- an issue that took on new urgency in the aftermath
of Hurricane Andrew, when tons of demolition materials were added to the waste
stream.
"Arsenic," Hauserman wrote, "is leaking out of huge wooden playgrounds that
volunteers built all over Tampa Bay. It's leaking beneath decks and state park
boardwalks, at levels that are dozens of times -- even hundreds of times --
higher than the state considers safe. And discarded pressure-treated lumber is
leaking arsenic out of unlined landfills... posing a threat to drinking water."
The spring 2001 publication of Hauserman's investigation was a cultural tipping
point. Time magazine, the New York Times, and the Los Angeles Times all followed
up with investigative stories of their own, as did local television stations
throughout the country. Bills were introduced in Congress and in the Florida
legislature; class actions suits were filed.[29] Many parents, school boards,
and parks superintendents did not wait for the outcome of these legal
initiatives. Day care centers ripped out play structures. Arsenic-contaminated
playgrounds closed throughout Florida and around the nation -- including some in
Rochester, New York, where citizen activists had been unsuccessfully pushing for
their closure since 1990.[28] In May 2001, the city council of Cambridge,
Massachusetts passed a resolution to "replace all existing City playground and
park equipment constructed with CCA-treated wood with arsenic-free alternatives
on an expedited, specific time table."[29]
The following fall, EWG and HBN released a new report about arsenic levels in
lumber purchased at Lowe's and Home Depot. Shoppers were sent into retail
outlets in 13 states to purchase pressure-treated lumber. (Note: not a single
buyer was offered the safety warnings required by law.) Arsenic was easily wiped
off the surface of all purchased wood -- at levels up to 1,000 micrograms per
100 square centimeters, which is about the size of a four-year-old's handprint.
This was considerably more arsenic than the EPA's allowable exposure level for
arsenic in drinking water.[30]
Good investigative journalism, combined with the advocacy work of EWG and HBN,
had a powerful effect. Catapulting the issue of pressure-treated wood further up
the chain of command was blue-chip science. In September 2001, the National
Academy of Sciences announced, based on new findings from Chile and Taiwan, that
the cancer risks from arsenic in drinking water were even greater than estimated
in their ground-breaking 1999 report.[31] The EPA now had little choice about
adopting the stricter drinking water standards that it had been quietly trying
to back away from. And the dangers of arsenic were in the news again.
In February 2002, the EPA announced that it had reached an agreement with the
timber industry: CCA production would be phased out over a 22-month period.[32]
This delay was to allow wood treatment facilities to convert to alternative
chemicals, such as ACQ, a copper-based preservative. (Arsenic-free ACQ wood has
been available in Europe for many years. Because it contains more copper, it is
more expensive than CCA.) As of January 1, 2004, CCA would no longer be
registered for use
to treat wood intended for residential settings. While stores would still
legally be allowed to sell left-over stock after the New Year's Eve deadline,
the vice president of merchandizing for Home Depot pledged in the pages of the
Washington Post that the process of phasing in alternatives to CCA wood "will be
complete by December 31."[33]
It was not. At this writing, the shelves of many home improvement stores are
still full of CCA lumber for sale to unsuspecting buyers. The ban is still on
the books -- but not in the stores, many of which have enough stock to last for
months to come.[34] Moreover, there is still no plan to remediate all the
structures already built from CCA wood. What happened? [To be continued.]
*Sandra Steingraber, Ph.D., is a biologist and author (see Rachel's #565, #658,
#776, #777). She is currently a Distinguished Visiting Scholar in the
Interdisciplinary Studies Program at Ithaca College in Ithaca, New York. The
following web sites are all excellent sources of information on CCA wood and
provide assess to many key documents and reports:
http://www.ccaresearch.org
http://www.bancca.org
http://www.noccawood.ca
http://www.beyondpesticides.org
http://www.healthybuilding.net
[1] European Environment Agency, Late Lessons from Early Warnings: The
Precautionary Principle 1896-2000 (Luxembourg: Office for Official Publications
of the European Communities, 2001) Available at
http://www.rachel.org/library/getfile.cfm?ID=301
[2] Late Lessons, p. 11.
[3] David Gee, personal communication (david.gee@eec.eu.int).
[4] C. Cox, "Chromated Copper Arsenate," Journal of Pesticide Reform Vol. 11
(1991), pgs. 2-6.
[5] U.S. Environmental Protection Agency, "Cancellation of Residential
Uses of CCA-Treated Wood: Questions and Answers," (20 March 2003;
http://www.epa.gov/pesticides/factsheets/chemicals/1file.htm)
[6] U.S. Environmental Protection Agency, A Probabilistic Risk Assessment for
Children Who Contact CCA-Treated Playsets and Decks (13 Nov. 2003;
http://www.epa/gov/scipoly/sap )
[7] N. Tulve and others, "Frequency of Mouthing Behavior in Young Children,"
Journal of Exposure Analysis and Environmental Epidemiology Vol. 12 (2002), pgs.
259-64.
[8] U.S. Agency for Toxic Substances and Disease Registry, "ToxFAQs for
Arsenic," 2001;
http://www.atsdr.cdc.gov/tfacts2html
[9] D.A. Belluck and others, "Widespread Arsenic Contamination of Soils in
Residential Areas and Public Spaces: An Emerging Regulatory or Medical Crisis?"
International Journal of Toxicology Vol. 22 (2003), pgs. 109-128.
[10] Evidence is reviewed in Belluck (see note 9 above.)
[11] P.A. Cooper, "Future of Wood Preservation in Canada: Disposal Issues,"
paper presented at the 20th Annual Canadian Wood Preservation Association
Conference, Vancouver, BC (http://www.forestry.utoronto.ca/treated_wood/future.pdf)
[12] I. Lerner, "Potential Litigation Creates Concern for Wood Preservatives,"
Chemical Market Reporter, 14 Oct. 2002, p. 14
(http://www.chemicalmarketreporter.com).
[13] D. Hopey, "Wood Treatment Linked to Dangers," Pittsburgh Post-Gazette 25
Jan. 1998. (Available on http://www.bancca.org.)
[14] C. Rist, "Arsenic and Old Wood," This Old House, Mar. 1998, pp.118-25.
[15] Belluck (cited above in note 9). (See also historical timeline provided on
http://www.bancca.org.)
[16] This history is described in Cox, 1991 (see note 4, above). See also G.
Kidd, "CCA-Treated Lumber Poses Danger from Arsenic and Chromium, Pesticides and
You Vol. 21 (2001), pgs. 13-15. (Available on
http://www.beyondpesticides.org.)
[17] J. Hauserman, "Treated Wood Industry Fights Back," St. Petersburg Times, 2
July 2001;
http://www.sptimes.com/News/070201/Treated_wood_industry.shtml
[18] W. Takahashi and others, "Urinary Arsenic, Chromium, and Copper Levels in
Workers Exposed to Arsenic-Based Wood Preservatives," Archives of Environmental
Health Vol. 38 (1983), pgs. 209-14; Cox, 1991 (cited in note 4, above); H.A.
Peters and others, "Seasonal Arsenic Exposure from Burning
Chromium-Copper-Arsenate Treated Wood," Journal of the American
Medical Association Vol. 251 (1984), pgs. 2393-96.
[19] U.S. Consumer Product Safety Commission, Estimate of Risk of Skin Cancer
from Dislodgeable Arsenic on Pressure-Treated Wood Playground Equipment
(Washington, D.C., 1990).
[20] National Research Council, Arsenic in Drinking Water (Washington, D.C.:
National Academy of Sciences, 1999).
[21] R.C. Kaltreider at al, "Arsenic Alters the Function of
Glucocorticoid Receptor as a Transcription Factor," Environmental Health
Perspectives Vol. 109 (2001), pgs. 245-51.
[22] D. Stilwell and K.D. Gorney, "Contamination of Soil with Copper, Chromium,
and Arsenic Under Decks Built from Pressure-treated Wood," Bulletin of
Environmental Contamination and Toxicology Vol. 67 (1997), pgs. 303-08.
[23] Belluck (cited above in note 9).
[24] Environmental Working Group and Healthy Building Network, Poisoned
Playgrounds: Arsenic in Pressure-Treated Wood (Washington D.C.: May
2001;
http://www.ewg.org/reports/poisonedplaygrounds)
[25] Environmental Working Group and Healthy Building Network, "Petition to the
United States Consumer Product Safety Commission to Ban Arsenic-Treated Wood in
Playground Equipment and Review the Safety of Arsenic-Treated Wood for General
Use," May 22, 2001
(http://www.ewg.org/reports/poisonedplaygrounds/petition.pdf).
[26] J. Hauserman, "The Poison in Your Backyard," St. Petersburg Times, 11 March
2001. (http://www.sptimes.com/News/webspecials/arsenic)
[27] M. Dunne, interview with Julie Hauserman in SEJournal, Society of
Environmental Journalists, Winter, 2001, p. 1.
[28] Contact Rochesterians Against the Misuse of Pesticides for this fascinating
history: Judy Braiman, 716-383-1317.
[29] Cambridge (Mass.) City Council meeting, 7 May 2001.
[30] Environmental Working Group and Healthy Building Network, The Poisonwood
Rivals (Washington, D.C.: Nov. 2001;
http://www.ewg.org/reports/poisonwoodrivals/)
[31] National Research Council, Arsenic in Drinking Water: 2001 Update
(Washington, D.C.: National Academy of Sciences, 2001).
[32] U.S. EPA, 2003 (cited above in note 5).
[33] J.M. Lerner, "New Rules on Treated Wood to Change the Backyard World,"
Washington Post, Sept. 6, 2003, p. G2.
[34] G.C. Bruno, "Confusing Phaseout," Gainesville Sun, Jan. 24, 2004. RACHEL'S
ENVIRONMENT & HEALTH NEWS Environmental Research Foundation P.O. Box 160 New
Brunswick, N.J. 08903 Fax (732) 791-4603; E-mail:
erf@rachel.org
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