Environmental and labor groups from the U.S. and Canada have teamed up in a lawsuit challenging the continued U.S. use of wood preservatives containing arsenic and other harmful substances. The groups say the U.S. Environmental Protection Agency has "overwhelming data" regarding the health and environmental risks posed by the preservatives, and cite the availability of safer, affordable alternatives. Citing "inadequate and long delayed" government action on wood preservatives, the groups filed suit in federal district court in Washington DC, asking the court to force the EPA to halt all use of the wood preservatives chromated copper arsenate (CCA), pentachlorophenol (penta) and creosote.