Arsenic has taken a big hit recently—from studies showing elevated levels in school playgrounds in Florida to public outcry about President Bush’s decision to relax drinking water standards for the element. Not surprisingly, product manufacturers are getting the message. In the July/August issue of
EBN (
Vol. 10, No. 7/8) we reported on one playground equipment manufacturer abandoning CCA; in this issue we report on another: Kompan (see newsbrief at left). In a directly related move, one of the largest manufacturers of CCA has introduced to the U.S. market a nonarsenic, nonchromium replacement for CCA: Wolman
® E.
Arch Wood Protection, Inc., a division of Arch Chemicals, Inc., which acquired Hickson International PLC in August 2000, now offers a copper-based preservative in its “Wolmanized
®” line of chemicals for pressure-treating lumber. Wolman E has been available in Europe since 1992 under the trade name Tanalith E. It was referred to as “Copper Azole” in our March 1997 article addressing problems with disposal of CCA-treated wood (
EBN
Vol. 6, No. 3); at that time, Hickson had chosen not to market the chemical in the U.S. Wolman E is now licensed to seven pressure-treating plants in the U.S., with two to four others expected by the end of the year. Pressure-treated wood produced with Wolman E is being marketed under the name Natural Select™. Natural Select was first produced in the United States in the fall of 2000. Wood treaters that currently produce Natural Select treated wood are currently located in South Carolina, Louisiana. Pennsylvania, California, Oregon, and Washington.
Wolman E differs in a number of ways from ACQ Preserve™, the other widely marketed alternative to CCA. According to Huck DeVenzio, Marketing Manager for Arch Wood Protection, Inc., both ACQ and Wolman E are copper-based, but they rely on different co-biocides to supplement the primary fungicide: copper. “We think our preservative is superior because of its lower corrosivity and because our co-biocide has lower toxicity characteristics than the quaternary compounds used by our competitors,” said DeVenzio. Wolman E includes borates to improve decay resistance, though the company does not seem convinced that the borates really improve long-term performance. Pointing out that no one has yet found a way to lock borates into wood, DeVenzio said that “long-term testing has demonstrated that Natural Select wood does not rely on the borate for its effectiveness. Future versions of the product may not include the borate.” Arch Chemicals is quick to point out that it remains fully committed to CCA and that the introduction of Wolman E in no way implies that there is anything wrong with the more common arsenic- and chromium-containing compounds. “We believe CCA serves and continues to serve many customers’ needs in terms of a long-lasting and easily available product,” said DeVenzio. The company says that alternative wood treatment technologies are emerging because of both regulatory restrictions and consumer concerns prompted by media reports. “Despite the lack of a scientific basis,” says DeVenzio, “these trends are happening; we recognize this and offer Natural Select wood as an alternative choice.”
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