Inorganic Arsenical Pressure-Treated Wood
[Including Chromate Copper Arsenate (CCA), Ammoniacal Copper Arsenate (ACA), and
Ammoniacal Copper Zinc Arsenate(ACZA)]

Consumer Information:

February 12, 2002

On February 12, 2002, EPA announced a voluntary decision by industry to move consumer use of treated lumber products away from a variety of pressure-treated wood that contains arsenic by December 31, 2003, in favor of new alternative wood preservatives. This transition affects virtually all residential uses of wood treated with chromated copper arsenate, also known as CCA, including wood used in play-structures, decks, picnic tables, landscaping timbers, residential fencing, patios and walkways/boardwalks. As of January 1, 2004, EPA will not allow CCA products to be used to treat wood intended for any of these residential uses. This decision will facilitate the voluntary transition to new alternative wood preservatives that do not contain arsenic in both the manufacturing and retail sectors. Although the Agency has not concluded that there is unreasonable risk to the public from these products, we do believe that any reduction in exposure to arsenic is desirable. This action comes years ahead of completing the Agency's regulatory and scientific assessment of CCA and will result in substantial reductions in potential exposure to CCA.

After December 31, 2003, wood treaters will no longer be able to use CCA to treat wood intended for use in decks, picnic tables, landscaping timbers, gazebos, residential fencing, patios, walkways/boardwalks, and play-structures. Wood treated prior to this date, however, can still be used in residential settings. Already built structures containing CCA-treated wood are not affected by this action.

EPA has not concluded that CCA-treated wood poses any unreasonable risk to the public or the environment. Nevertheless, arsenic is a known human carcinogen and, thus, the Agency believes that any reduction in the levels of potential exposure to arsenic is desirable. EPA believes that the voluntary transition to non-arsenical containing wood preservatives for residential sites is a responsible action by the registrants.

EPA does not recommend that consumers replace or remove existing structures made with CCA-treated wood or the soil surrounding those structures. Concerned citizens may want to take extra precautions, however, by applying a coating to exposed surfaces on a regular basis. (See below for more information on coating structures.)

While available data are very limited, some studies suggest that applying certain penetrating coatings (e.g., oil-based, semi-transparent stains) on a regular basis (e.g., once per year or every other year depending upon wear and weathering) may reduce the migration of wood preservative chemicals from CCA-treated wood. In selecting a finish, consumers should be aware that, in some cases, "film-forming" or nonpenetrating stains (e.g., latex semitransparent, latex opaque, and oil-based opaque stains) on outdoor surfaces such as decks and fences are not recommended, as subsequent peeling and flaking may ultimately have an impact on durability as well as exposure to the preservatives in the wood. Talk with your local hardware store about available coatings.

Freshly treated wood, if not coated, has a greenish tint, which fades over time. As a practical matter, CCA has been the principal chemical used to treat wood for decks and other outdoor uses around the home. Generally, if your deck has not been constructed with redwood or cedar, then most likely the deck was constructed with CCA-treated wood. Alternatively, if you know who constructed the deck, you may want to call and ask.

A number of preservatives have been registered by EPA, and wood treated with these preservatives are expected to be available in the marketplace. In addition, untreated wood (e.g., cedar and redwood) and nonwood alternatives, such as plastics, metal, and composite materials are available. Your local hardware store or lumberyard can provide more information about available alternatives.

The Permanent Wood Foundation was not noted in the report. CCA preservatives will be used for PWFs after 2003.