Persistence, leaching and availability of chromated-copper-arsenate polyethylene glycol, copper naphthenate and pentachlorophenol wood preservatives from pressure treated utility poles

The exposure of chromated-copper-arsenate polyethylene glycol, copper naphthenate and pentachlorophenol pressure treated utility poles to acidic leaching environments was examined. Exposure of CCA-PEG poles to a citric acid/sodium hydroxide buffer solution resulted in significant loss of CCA components. Reduction of leaching solution pH resulted in corresponding increases in loss of Cu, Cr and As. Total losses of Cu, Cr and As from treated poles were approximately 84.1, 48.7 and 29.6 g/m;The toxic effect of CCA-PEG and copper naphthenate leachate to zooplankton and freshwater algae was examined through bioassays with Daphnia magna and Selenastrum capricornutum. The 48hr LC50 concentration for D. magna to CCA leachate corresponded to Cu, Cr and As concentrations of 36.0, 0.5 and 4.1 ;The potential for vertical movement of CCA and copper naphthenate leachates through soil was evaluated by passing the equivalent of one years leachate through three Ontario soils. (Abstract shortened by UMI.).