News Coverage
Arsenic-Treated Wood May Pose Risks
Published August 28, 2002
After tests of several hundred wood decks and playsets, an environmental group says the risks of being exposed to arsenic from treated, pressurized wood is just as great in old, worn structures as with freshly treated lumber.
The Environmental Working Group said Wednesday that tests conducted by volunteers in 45 states showed that the age of the structures had no effect on arsenic levels found on the surface of the treated wood. Some tests also showed arsenic in soil near or under the structures at levels many times higher than the cleanup standard at a Superfund toxic waste site. In February, lumber companies, in an agreement with the Environmental Protection Agency, said they would phase out the use of an arsenic-based preservative in pressure-treated wood. They said that after December 2003 they no longer would use chromated copper arsenate, or CCA, a powerful pesticide, to protect lumber from decay and insect damage. But the EPA, as part of the agreement, also said it did not believe there was any reason for people to replace the CCA-treated wood, which is used in an estimated 90 percent of all outdoor wooden structures such as decks, play sets and picnic tables.
Arsenic is known to cause cancer and has been at the center of a dispute over how much of it should be allowed in drinking water. The new study claims that "wipe tests" on the wood surfaces of many of the structures produced three to 10 times the arsenic now allowed in drinking water.
EPA spokeswoman Steffanie Bell said the agency had not reviewed the group's results and planned its own formal risk assessment next year. "Right now we don't have any indication that (the wood) poses an unreasonable risk to the public, but we need to get additional information," said Bell.
Jane Houlihan, research director for Environmental Working Group, said the "wipe tests" - using kits provided by the group - showed that the amount of arsenic coming off the wood in many cases exceeds what levels allowed in drinking water by the EPA.
In about one quarter of the samples, the amount of arsenic wiped off the wood surface was at least three times the 10 micrograms that is the most allowed in a liter of tap water. In some samples the amount - collected from an area about size of a child's two hands - was up to 250 micrograms, the group said.
"There's no question that kids are ingesting (arsenic)," Houlihan said in an interview, because children routinely touch the wood and then put their fingers into their mouths.
The group distributed nearly 1,000 test kits, got about half back and sent 263 samples - all those involving structures where children might be most exposed - to the Environmental Quality Institute at the University of North Carolina-Asheville for analysis.
In some samples where soil was tested near the under the structures, the arsenic levels far exceeded the 20 parts per million required in cleaning up a Superfund toxic waste site, said the EWG report. It cited soil beneath a deck in Irvington, N.Y., with 113 part per million arsenic, and a sandbox under a wooden play set in Newton, Mass., that had 32.4 parts per million.
Structures more than 20 years old and those less than a year old showed similar results, the report found. Deck sealant appeared to reduce surface arsenic levels for about six months but then made little if any difference.
The group did not recommend people take the costly step of replacing their decks but said they could seal the wood every six months, replace high-exposure sections with another type of wood, have children wash their hands after playing, or cover picnic tables with a tablecloth before using. The wood preservative industry cited past statements by physicians that the CAA-treated wood has never been linked to skin disease or cancer in children although it has been used for decades. The industry says such wood is safe when used properly.