Pressure-Treated Wood 

Virtually all of the lumber sold for outdoor use in the U.S. is pressure-treated and injected with toxics to preserve the wood and prevent bug damage. The most commonly used wood preservative and pesticide is chromated copper arsenate (“CCA”). The main toxic components of CCA are arsenic and hexavalent chromium. A 12-foot section of pressure-treated lumber can contain up to one ounce of arsenic, or enough to kill 250 people. CCA-treated lumber often has a characteristic green tint. It is difficult, however, to distinguish CCA-treated wood from untreated wood after the wood has aged and lost its green tint.

Health Hazards: Arsenic is classified as a human carcinogen and has been shown to increase the risk of skin cancer and a variety of internal cancers. The extent of the public health threat from arsenic exposures from pressure-treated wood products is still unknown. The state of Connecticut’s health department has been a leader in researching this issue. Several years ago the department issued a warning about CCA-treated wood in playgrounds, noting that exposure from CCA-treated wood can be a major source of arsenic to children because it is easily taken up onto hands from contact with the surface and may be swallowed with hand-to-mouth activity.

How to Avoid or Minimize Exposure:
Wear gloves and dust masks when sawing treated wood. Make sure to catch the sawdust for trash disposal off site.  Wash your hands, and particularly your children’s hands, after touching the pressure-treated wood. Do not burn scraps as they may give off toxic smoke and create toxic ash.  Use alternatives to wood or build with chemical-free wood products.

The Environmental Protection Agency has announced that CCA-treated lumber sold in the U.S. will contain a warning label, and stores will be provided with stickers and signs for their displays. Other agencies and states are responding to the public’s concerns.  For example, the Consumer Product Safety Commission has agreed to ask for public Comments on petitions that could lead to an outright ban of CCA. And in Florida, dozens of playgrounds with treated wood equipment have been shut down.

Links to Related Resources

ERF Chemical Fact Sheet for Arsenic