Arsenic timber treatments review history and regulatory outcomes

Nomination for review

In March 2003 the APVMA announced its decision to review the registration of timber treatment products containing arsenic. Arsenic timber treatments were nominated for review because of information that suggested that arsenic might leach out of treated timber and pose a risk to people and the environment.

Preliminary review

In December 2003 the APVMA released the Arsenic Timber Treatments Preliminary Review Findings Report* for public comment. In the preliminary review, the APVMA looked at a variety of issues related to protection of the environment, worker safety and residues in commodities.

The APVMA considered all of the information available, including submitted data, public submissions and advice from APVMA’s advisory agencies (the Australian Government Department of Health and Ageing and the Department of the Environment and Heritage). The APVMA proposed that:

• to protect timber treatment workers and the environment, CCA product labels should be amended to include more detailed instructions for timber treatment operations, waste management and disposal
• CCA timber treatment products should be declared to be restricted chemical products (RCP)
• supply and use of CCA timber treatment products should be restricted to authorised persons
• registrations and approvals for arsenic trioxide products could continue as before.

Final review and outcomes

In March 2005 the APVMA released the Arsenic Timber Treatments Final Review Report. The APVMA found there could possibly be a health risk for people, particularly children, who had frequent and close exposure to CCA-treated timber such as decks, garden furniture and playground structures.

However, there was no evidence to justify cancelling the use of CCA to treat timber for materials such as telegraph poles, fence posts, fence palings or other structural timbers, where frequent contact is unlikely. For these uses the levels of exposure, and hence the health risks, are low.

In the final review the APVMA recommended:

• cancelling the use of CCA used in situations where people might come into frequent contact with the treated timber. These uses might include garden furniture, picnic tables, exterior seating, children’s play equipment, patio and domestic decking, and handrails (7 June 2006).
• permitting the continued use of CCA to treat timber in situations where there would not be frequent and intimate contact with people. Acceptable uses include power and telegraph poles, fencing, building structural uses and a range of other uses
• varying product labels to include more detailed instructions for timber treatment operations, including waste management and disposal and protection of the environment
• requiring that timber treated with CCA is clearly identified.

Use patterns for arsenic trioxide were determined to present a low risk to public health. Only trained, authorised pest control operators can use arsenic trioxide and the areas of treated timber are concealed.

For more information please contact the Chemical Review Program on (02) 6210 4749 or by email to chemrev@apvma.gov.au

* Contact the APVMA for copies of this report.