MEDIA> CCA-TREATED TIMBER
CCA Treated Timber (Copper Chrome Arsenic)
Arsenic based timber treatments will be phased out in the US by the end of this year. Sandra Steingraber looks at the lessons learned in the US in this article from Rachel's Environment and Health News Feb 2004. The use of CCA in Australia is under investigation because of new evidence that it is unsafe. But what about the existing decks, cubby-houses, schools and public playgrounds?
 For 60 years, wood treated with copper, chromium and arsenic has been the preferred solution for a long-lasting, low-cost wooden structure around the home. The timber has also been extensively utilised in park benches, tables, and climbing structures. Evidence against using these products has been mounting, and a risk and hazard analysis is now under way at the Australian Pesticides and Veterinary Medicines Authority. The organisation’s board has already indicated it plans to stop the use of CCA treated timber in certain domestic situations, unless there is conclusive proof that continued use is safe.
Sharon Beder, Professor of Science and Technology at Wollongong University, has analysed the international research on CCA timber and its possible impact on human health. The problem is that over time, as particularly the arsenic leaches out onto the surface of the wood, anyone who touches the wood gets arsenic on their hands. This leaching can go on for up to 20 years, with no reduction in toxicity.
The Croydon Conservation Society in Victoria tested some CCA treated playground equipment in June this year. Their tests revealed staggering levels of not only arsenic, but also chromium and copper. The highest levels wiped from the surface of the timber were 710 micrograms of arsenic, 630 micrograms of chromium and 670 micrograms of copper. To put that into perspective, the level of arsenic available to children on the surface of the timber far exceeds the maximum amount of arsenic allowed in a glass of drinking water. 
Arsenic is a known carcinogen, an endocrine system disruptor and can be toxic to the skin and internal organs. Chromium accumulates in tissues, is a strong skin irritant and a potent skin allergen. There is no data on the effects of ingesting chromium, arsenic and copper together. Burning CCA treated timber releases toxic amounts of arsenic gas. Gloves are recommended to be used when handling CCA treated timber.
A study by the US Consumer Product Safety Commission has found that children between two years and six years old who regularly play on CCA treated playground equipment have a significantly increased lung or bladder cancer risk over their lifetimes.
Professor Beder told Earthbeat (13/09/2003) that some countries have banned treated timber outright. For example, Switzerland, Vietnam and Indonesia. Some countries have severely restricted it, for example Japan, Sweden and Germany. The European Commission has issued a directive that treated timber should not be marketed except for selected industrial purpose. In the US there’s a voluntary phase-out of CCA treated timber for residential uses, and that will become official in January next year.
What will be done to deal with the problem of existing CCA treated timber structures?
Paints and varnishes have been shown to be temporary fixes only. Alternative wood preservatives are available, without the chromium or the arsenic, but are not widely available. LOSP, or Light Organic Solvent Preservative, is a combination of a solvent and a preservative, such as linseed and kerosene. It is suitable for decks and for house framing, and is quite widely available in Sydney and through a number of outlets in Melbourne, and Brisbane.
CCA-treated timber currently goes to landfill in Australia, but is treated as hazardous waste elsewhere in the world.
As consumers and parents, we can demand a national strategy to deal with this problem.
Some ideas that spring to mind are:
A set of guidelines for schools and childcare centres on existing CCA structures
Warning signs on all public structures
Promotion of solutions and safer alternatives through the media and all relevant organisations and departments.
Further Information
Arsenic Based Timber Treatments FAQ
Australian Pesticides and Veterinary Medicines Authority (APVMA)
http://www.apvma.gov.au/chemrev/arsenic_faq.pdf
Ecospecifier
A guide to sourcing environmentally preferable materials.
http://ecospecifier.org
PINETEC
Major West Australian based supplier of Copper Azole
treated timber (sold under the trade name Tanalith-E)
http://www.pinetec.net/
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