Chromated Copper Arsenate (CCA), which was used to preserve pressure treated wood, is the subject of several studies and news articles. There exists a potential danger to people who come in contact with them on a regular basis. Other wood preservatives are also harmful but not as news worthy.

Below you'll find links to study reports provided by scientists and educational research facilities concerning CCA, how its use in outdoor wood is necessary, and the types of coatings required to protect you from them. Notice that CCA was used to keep the wood from decay and that the coatings recommended by these studies are high molecular weight polymers, just like EPL. Other leading deck-coating products do not provide the substantial coating that is suggested for protection from CCA.

CCA's are no longer allowed in outdoor lumber. A new lumber treatment called ACQ (Alkaline Copper Quaternary) is a non-arsenic pressure treatment that has less history in protection of the rot and appearance of your outdoor wood. We would recommend staining this type of wood with a non water-repelant type stain then applying EPL to keep your outdoor wood beautiful.

 

There exists some disagreement on the hazard of CCA. There was, however, consensus among the experts on the need to "inform the public of the ability of certain coatings to substantially reduce leachable and dislodgeable CCA chemicals and thus to reduce potential exposure to arsenic and chromium" and to "begin advising the public about the use of coatings now". They also indicate ".....water repellants are ineffective." (answer to question 15) pg. 54

See page 37 of 84 for the following excerpt: Supplemental treatments include water sealants and plastic coverings for CCA-treated wood products. These treatments EPL to maintain the CCA chemical within the wood product thereby providing greater protection against decay. (Archer, personal communication, 1998).