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Pressure-treated Wood Containing Arsenic: Is it Dangerous? Chromated copper arsenate, or CCA, is a chemical compound mixture containing inorganic arsenic, copper and chromium that has been used for wood preservation since the 1940s. CCA is injected into wood by a process that uses high pressure to saturate wood products with the chemicals. CCA is intended to protect wood from dry rot, fungi, molds, termites, and other pests. On February 12, 2002, EPA Administrator Christie Whitman announced a voluntary decision by industry to move away from consumer use of arsenic-containing treated lumber products by Dec. 31, 2003. New alternative wood preservatives will be used instead. By Jan. 2004, EPA will not allow CCA products for virtually any residential uses, including wood used in play-structures, decks, picnic tables, landscaping timbers, residential fencing, patios and walkways/boardwalks. EPA has not concluded that CCA-treated wood poses unreasonable risks to the public for existing CCA-treated wood being used around or near homes or from wood that remains available in stores. EPA does not believe there is any reason to remove or replace CCA-treated structures, including decks or playground equipment. EPA is not recommending that existing structures or surrounding soils be removed or replaced. 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 (one re-application per year or every other year depending upon wear and weathering) may reduce the migration of wood preservative chemicals from CCA-treated wood. Arsenic is linked to certain types of cancers and, thus, the Agency believes that any reduction in the levels of potential exposure to arsenic is desirable. Use-Site Precautions: All sawdust and construction debris should be cleaned up and disposed of after construction. Do not use treated wood under circumstances where the preservative may become a component of food or animal feed. Examples of such sites would be use of mulch from recycled arsenic-treated wood, cutting boards, counter tops, animal bedding, and structures or containers for storing animal feed or human food. Only treated wood that is visibly clean and free of surface residue should be used for patios, decks and walkways. Do not use treated wood for construction of those portions of beehives which may come into contact with honey. Treated wood should not be used where it may come into direct or indirect contact with drinking water, except for uses involving incidental contact such as docks and bridges. Handling Precautions: Dispose of treated wood by ordinary trash collection. Treated wood should not be burned in open fires or in stoves, fireplaces, or residential boilers because toxic chemicals may be produced as part of the smoke and ashes. Treated wood from commercial or industrial use (e.g., construction sites) may be burned only in commercial or industrial incinerators or boilers in accordance with state and Federal regulations. Avoid frequent or prolonged inhalation of sawdust from treated wood. When sawing, sanding and machining treated wood, wear a dust mask. Whenever possible, these operations should be performed outdoors to avoid indoor accumulations or airborne sawdust from treated wood. When power-sawing and machining, wear goggles to protect eyes from flying particles. Wear gloves when working with the wood. After working with the wood, and before eating, drinking, toileting, or using tobacco products, wash exposed areas thoroughly. Because preservatives or sawdust may accumulate on clothes, they should be laundered before reuse. Wash work clothes separately from other household clothing. More information is available at http://www.epa.gov/pesticides/factsheets/chemicals/1file.htm
Author: Mary E. May, RN, BA, MPH
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