Chromated Copper Arsenate is a pesticide used as a lumber preservative, consisting of arsenic, chromium, and copper. The EPA is currently reassessing the use of CCA:
On February 12, 2002, EPA announced a voluntary decision by industry to move consumer use of treated lumber products away from ... wood that contains arsenic by December 31, 2003, in favor of new alternative wood preservatives. ... By January 2004, EPA will not allow CCA products for any ... residential uses.
Although CCA has been in use since 1940 in the US, it has been more recently banned in other countries, as it has a bad habit of leaching arsenic into the surrounding soil if the wood is not also sealed and re-sealed on a regular basis.

Alternatives to CCA treated wood include:

EPA final report: "Preliminary Evaluation of the Non-dietary hazard and Exposure to Children from Contact with Chromated Copper Arsenate Treated Wood Playground Structures and Contaminated Soil."

Log in or register to write something here or to contact authors.