Arsenic-treated wood linked to increased cancer risk, CPSC says.

Playground equipment made from wood treated with chromated copper arsenate (CCA) puts children at increased risk of developing lung or bladder cancer, according to a recent study by the Consumer Product Safety Commission (CPSC). The report marks the first time a government agency has acknowledged the dangers of arsenic-treated wood. (The study is available at www.cpsc.gov/library/foia/foia03/ brief/cca0.pdf.)

"This shows that independent groups are recognizing the inherent dangers of this wood, and shows why it is unfit for the purposes for which the manufacturers have been selling it," said Eulis Simien of Baton Rouge, Louisiana, who represents plaintiffs in treated-wood litigation. (As Arsenic Leaches, Pressure Builds on Treated-Wood Industry, TRIAL, Nov. 2002, at 12.)

In May 2001, the Environmental Working Group (EWG) and the Healthy Building Network (HBN) petitioned the CPSC to ban the use of CCA-treated wood in playground equipment. In response, the commission launched a study to determine the risks, if any, to children from direct contact with the wood.

The study involved field tests of 20 CCA-treated wood structures (8 decks and 12 play sets) in the Washington, D.C., metropolitan area. Using adult hands and cloth swabs, researchers measured the "dislodgeable arsenic levels" on the surface of the wood and how much rubbed off from direct contact. They correlated their findings with data from published studies linking exposure to high levels of arsenic in drinking water in Taiwan to increased risk of lung and bladder cancer.

The researchers concluded that "a young child who plays on CCA-treated wood playground structures in early childhood has an increased risk of 2 to 100 per million of developing lung or bladder cancer during his or her lifetime."

However, they recommended that the commission defer action on the EWG/HBN petition until after the Environmental Protection Agency (EPA) completes its plan to phase out the wood. In March, the EPA finalized a voluntary phase-out agreement with wood-treatment companies, which stipulates that after December 30, 2003, CCA may not be used to treat wood intended for residential uses and for structures in public playgrounds. The plan will allow sale of wood already treated by that date, and will not affect existing structures.

In testimony before the CPSC regarding the petition, Jane Houlihan, EWG's vice president for research, criticized the study for underestimating the risks and failing to recommend action. She pointed to two studies released earlier this year that were not considered in the commission's risk assessment.

An EPA cancer-risk assessment released in March found that children ages 2 to 15 are three times more vulnerable to carcinogens than adults are. The other study, conducted by the National Cancer Institute and the National Institute of Environmental Health, found that in mice, a 10-day exposure to arsenic in utero increased rates of malignant, benign, and precancerous lesions in later life.

The Treated Wood Council and the American Wood Preservers Institute, trade groups representing the manufacturers of CCA-treated wood, said the CPSC had released its study prematurely. In a press release, the groups pointed to other studies being conducted by federal agencies, in particular the EPA, and cautioned against drawing conclusions before all the data have been reviewed.

Jack Housenger, associate director of the EPA's Antimicrobials Division, testified at a CPSC hearing in March that the EPA is working on two risk assessments of CCA-treated wood. An occupational and environmental risk assessment, on hazards associated with uses not subject to the phase-out plan, will be released this spring.

A report on the EPA study of the risks to children is expected next year. The research includes a "surface bioavailablity study" to examine the surface residues of arsenic on the wood and how much of it the body can absorb; a "soil-residue bioavailability study" to estimate the amount of arsenic the body absorbs from contact with contaminated soil; and a "hand-wipe study" similar to the CPSC's research.

The CPSC and the EPA are also planning to jointly study ways to reduce the amount of arsenic that leaches from treated wood. For example, some evidence suggests that coating the wood with a penetrating stain or paint every year or two may seal the chemical into the wood. Some experts insist that arsenic does not leach to the surface when the wood is allowed to dry for a lengthy period after treatment. (Hasty Treatment Leads to Arsenic Leaching, TRIAL, Mar. 2003, at 12.)

In related news, a federal judge in Miami denied class certification in a suit filed on behalf of consumers who have CCA-treated wood structures on their property. Judge Donald Middlebrooks ruled that "the umpteen uses of treated wood and the diversity of climates to which the wood is exposed create great differences among the various plaintiffs in this matter." (Jacobs v. Osmose, Inc., No. 01-944-CIV-Middlebro, No. 01-944-CIV-Bandstra, 2003 WL 1060155 (S.D. Fla. Feb. 25, 2003).)