"Treated wood" is wood that has been impregnated with chemicals to make it resistant to insects, moisture and rot. The chemicals formerly used for this purpose — chromium, copper and arsenic (CCA) — are classified as pesticides, and have been shown to be toxic to humans. Arsenic and chromium VI are known human carcinogens, and arsenic has been linked to nervous system damage and birth defects.

Scientific studies show that chemicals from treated wood contaminate the surface of the wood and readily leach into the soil where children can be exposed through normal hand-to-mouth behavior.

A two-year manufacturing phaseout of CCA-treated wood began in February of 2002, but existing structures continue to present a risk. If the wood cannot be removed or replaced, it should be sealed annually with several coats of water-based latex paint or oil-based sealant to prevent the chemicals from leaching.

Resources:

The Safe Playgrounds Project was developed by the Center for Environmental Health. This is a general information site for parents and community members who want to learn more about the dangers of treated wood, as well as a link to order testing kits for wood or soil.

Beyond Pesticides, a non-profit advocacy organization, has created an excellent four-page "fact sheet' on CCA-treated wood.

Grassroots Environmental Education has extensive information and resources on treated wood playgrounds at their website.