It’s official: In February, after a series of meetings between the EPA and the three U.S. manufacturers of CCA preservatives, the federal environmental agency announced that all three will voluntarily phase out the arsenic-based preservatives. Wood treaters will begin converting existing plants to a new generation of much less toxic chemicals, and after December 31, 2003, CCAtreated lumber will be off limits for most nonindustrial uses. It will still be approved for utility poles, marine timbers and pilings, highway construction, and possibly some limited residential use, such as in plywood roof decking. No unreasonable risk. Although CCA-treated lumber has been in widespread use for more than half a century, for the past few years it has come under close scrutiny as a potential