Summary: Chromated copper arsenate, or cca, has been used to preserve wood since
the 1940's. The use of cca in residential applications was banned after
12/31/2003. Cca treated wood chemicals were found to dissolve in water
and leach out of the wood, causing potential harm. Sealing cca treated
lumber will reduce leaching of the chemicals. Be sure to use a
synthetic resin to keep the lumber from becoming a mildew and algae smörgåsbord and read these advisories for safe handling!