What is the chemical preservative used, and is it dangerous?
Until 2003, the preservative most commonly used in residential pressure-treated lumber was chromated copper arsenate (CCA), an extremely toxic chemical. CCA is so toxic that the Environmental Protection Agency, over 20 years ago, imposed strict guidelines regarding the manufacturing practices of companies using CCA. Your local home store or lumberyard is now selling lumber treated with less toxic alternatives… amine copper quat (ACQ) and copper azone (CA)… though you may find other chemical combinations in specific areas.
Until 2003, the preservative most commonly used in residential pressure-treated lumber was chromated copper arsenate (CCA), an extremely toxic chemical. Remember “Arsenic and Old Lace”? How about that old box of rat poison you have lurking in the garage? CCA is so toxic that the Environmental Protection Agency, over 20 years ago, imposed strict guidelines regarding the manufacturing practices of companies using CCA. However, one must distinguish between the toxicity of the chemical and the toxicity of the wood product in everyday use. Extensive studies were done since the mid 1980’s concerning the potential dangers of pressure-treated wood. And rightfully so! Large volumes of CCA were being used, and the treated wood products were beginning to be widely distributed, justifying the need for some hard research. The research was mixed, but the typical hysteria ensued as attorneys and plaintiffs lined up to claim damages from exposure to CCA. In the end, the industry agreed to voluntarily
