EPA, chemical firms working on phasing out preservative
Wood that's been pressure-treated with chromated copper arsenate to withstand insects and rot could vanish from building suppliers' shelves in the next few years because of concerns over the presence of arsenic, a carcinogen, in the preservative.
An agreement is pending between the Environmental Protection Agency and the chemical companies that produce the compound, abbreviated as CCA, which would result in CCA-treated lumber being phased out over the next few years, according to a report published in USA Today last week.
Treated lumber, more durable and weather resistant, is used for decks, fences and other outdoor structures Ñ including many children's playground structures Ñ a fact that heightened scrutiny of the arsenic-treated wood.
The preserved wood industry says the studies that found CCA-treated wood hazardous used questionable methodology. Handled properly, the industry says, the treated lumber is not unsafe. Arsenic is a naturally occurring element in the environment; however, consumption of it in large quantities has been linked to cancer, development of diabetes and damage to the vascular system.
But Jerry Parks, marketing director for the Western Wood Preservers Institute in Vancouver, Wash., concedes that 'when you have the word 'arsenic' in the product, it doesn't conjure up a lot of good images in the public eye.'
Because the chemical companies that produce CCA are in negotiations with the Environmental Protection Agency, spokesmen for the wood treatment industry are reluctant to talk about specific changes that could be coming Ñ in part because they haven't been privy to the talks.
Some manufacturers, responding to public concerns, already are opting to use different wood-preservative chemicals, however, and others are considering alternatives to CCA.
The largest share of the manufacturing plants for the country's $4 billion a year treated-wood industry is in the South, an abundant source of yellow pine, whose porous grain readily accepts the chemical treatment.
Parks estimates that Western companies account for only about 25 percent of the nation's pressure-treated wood. About 80 percent of locally treated wood is preserved with CCA, Parks says.
Hemlock and Douglas fir, the two woods most often used locally, are denser and less receptive to the preservative treatment. Incisions Ñ parallel rows of shallow dents ÑÊaid the treatment process.
Parks doesn't expect any plant closures in the West if there's an industrywide shift away from the use of CCA, although he adds, 'Certainly there will be an upfront financial expenditure to switch to a new treatment.'
In Oregon, there are treated-wood plants in Sheridan, Hillsboro, Scappoose, McMinnville, The Dalles, Medford, Eugene and Coos Bay. There are several companies in Washington, including two in Washougal.
At Exterior Wood Inc., in Washougal, one of the region's biggest treatment firms, about 40 percent of the lumber already is being treated with an alternative preservative called copper azole, which contains neither arsenic nor chrome, another ingredient in CCA.
Exterior Wood Operations Manager Tim Kredlo says one of the retail chains the firm supplies, Parr Lumber Co., now 'almost exclusively' sells treated lumber that is chrome- and arsenic-free.
Wood treated by Kredlo's company and other wood-treatment firms is sold with tags that caution that 'arsenic is in the pesticide applied to this wood' and direct consumers not to burn treated wood and to wear a dust mask and goggles when cutting or sanding the wood and gloves when working with it.