Health Risks of Pressure Treated Lumber
February 13, 2002 08:00
Regulators see substantial cancer risks in pressure treated lumber/wood that has been a staple of backyard building materials used for decking and railing projects.
Extent of risks may stay hidden
Copyright 2002 Gannett Company, Inc. USA TODAY...01/31/2002
WASHINGTON -- The Bush administration's push to end the use of pressure-treated lumber laced with arsenic leaves no doubt that regulators see substantial cancer risks in wood that has been a staple of backyard building projects. But the public may never get the government's final word on how big those risks may be.
In agreeing to phase out production of the wood, its manufacturers want the Environmental Protection Agency to put aside a long-awaited assessment of the threats faced by people exposed to the carcinogenic arsenic used in its treatment. It seems they will succeed: Industry and government officials involved in negotiations on a phase-out agreement say future risk studies probably will be limited to industrial uses of the treated lumber, such as guardrails and utility poles, which will still be allowed.
The phase-out agreement "indicates that (EPA) thinks there's enough of a problem to pressure the industry to get this lumber off the residential market, but not enough of a problem to seek an immediate ban" on its sale, says Jim Aidala, former assistant EPA administrator for pesticides.
Aidala, now an industry consultant with JSC Inc., says it would be typical for EPA to kill a product assessment once a phase-out is in place because it gives priority to assessing risks of products likely to stay on the market.
At issue is chromated copper arsenate, or CCA, an arsenic-based pesticide used on nearly all pressure-treated lumber. The willingness of the treated-wood industry to stop making CCA-laden lumber under a soon-to-be-final voluntary agreement is unlikely to quell debate on its safety.
There's strong evidence that arsenic from CCA can leach from pressure-treated wood for years, though the amount of the chemical that is released drops off in less than a year.
Some studies suggest that arsenic leaching from pressure-treated lumber can significantly raise risks of bladder, lung and other cancers in children who spend a lot of time playing on it. Competing studies funded by the wood-treatment industry suggest few if any risks beyond those associated with arsenic that occurs naturally, such as in soil or water.
The differences all boil down to the studies' methodology.
When an EPA Scientific Advisory Panel recommended last month that the agency's risk assessment should use the methodology favored by environmental and public interest groups -- a decision that probably would yield higher cancer-threat numbers -- the impetus for a phase-out agreement grew tremendously.
Previously, the wood-treatment industry agreed to voluntarily label CCA-treated lumber with a warning that advises the use of gloves and other protective clothing when working with the material. But environmental officials have complained that the labels are applied inconsistently.
"It was a voluntary agreement where our industry promised to do everything we could to get the message to the retail buyer, but everyone had to recognize that we couldn't control the retail situation," Parker Brugge of the American Wood Preservers Institute says.
Home Depot, Loews and other building supply stores, as well as manufacturers of CCA-treated lumber, have been subject to lawsuits, including a pending class-action case, alleging that they failed to adequately inform consumers of the lumber's risks.
Environmental groups recommend frequent sealing of the wood, preferably with an impervious paint or urethane-type coating. The Environmental Working Group also has teamed with an independent lab to offer the public at-cost arsenic testing kits through its Web site (www.ewg.org).
Many communities have begun using alternative products to build playgrounds and other public structures. Others have ordered frequent sealing of CCA-treated structures. In Florida, state parks are using arsenic-free wood on all new building projects. In California, state Sen. Gloria Romero is introducing legislation next month to ban all use of CCA-treated wood.
Within the wood-treatment industry, the move to alternative products has been slow. Dick Jackson, president of Pacific Wood Preserving, which owns treatment plants in four Western states, is an exception. He has shifted 65% of his pressure treating to non-CCA chemicals. He estimates that it costs anywhere from $ 80,000 to $ 120,000 to convert an average-sized CCA-treatment plant, mostly for new piping and spray equipment.
Jackson says CCA-treated wood is safe if dried and used properly. But because of competition, that doesn't always happen. "The cost of equipping your plant to make sure it's dry vs. switching to these alternatives, it's going to be more economical -- and politically correct -- to switch."