AbstractSamples of new and weathered utility lumber pressure‐treated with chromated copper arsenate (CCA) were tested for leaching of copper, chromium and arsenic by submersion in leaching baths of various pH levels. Accumulation of metals was monitored in leachate at pH 3.5, 4.5, 5.5, 7.0 and 8.5 over a period of 40 d by atomic absorption spectroscopy. Copper, chromium and arsenic were found in the leachate of both new and weathered wood with significantly higher levels of all metals occurring at acidic pH levels. Up to 100 of CCA treatment metals were found to have leached at pH 3.5, whereas a maximum of 9 of metals leached at pH 8.5. Metal leaching was found to be higher in citric acid than in dilute sulfuric acid solutions. Leaching of copper, chromium and arsenic was not proportional to the amount of metal present before leachin
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