ACQ treated pine is pine wood that has been treated with ACQ Preserve. ACQ Preserve is a specially formulated wood preservative that has removed most of the toxic elements traditionally found in wood preservatives. These offending elements are copper, chromium and arsenic. They have been used together for so long that they are commonly referred to in the industry as "CCA."

Starting in the 1930s, lumber companies started treating wood with chemical preservatives that contained CCA. CCA offered great protection against the chief enemies of wood: wood-eating insects such as ants and termites, water rot, deterioration due to extreme weather changes, and warping and cracking. For the rest of the 20th century, CCA was the industry standard in wood treatment chemicals.

The Birth of ACQ Treated Pine

However, all this changed at the end of the millennium when children's wooden playground sets, which have for decades been made with CCA-treated pine, were found to leach arsenic when they got wet. Arsenic can be deadly when ingested, as well as have untold disastrous effects on the environment. The result of this was an effective halt on the use of CCA in treated wood, and the search for a healthier alternative.

ACQ Preserve is an offshoot of this complicated history. Its formula is the result of much research and development to create an effective preservative without the presence of arsenic or chromium. The new process utilizes "copper plus quat" to arrive at a less toxic and more environmentally acceptable formula that is arsenic and chromium free.