Previous studies have shown that Cu, Cr, and As leach from chromated-copper-arsenate (CCA) pressure-treated wood and can be toxic to various estuarine organisms in the laboratory. The authors investigated concentrations of these metals in tissues of estuarine organisms, including algae, barnacles, and oysters, collected from CCA pressure-treated wood in a residential canal and Santa Rosa Sound, Florida. Organisms living on the open-water dock had significantly (P = .05) elevated concentrations of the contaminants from the wood, while those living inside the canal had considerably higher concentrations. The highest concentrations in barnacles were found in those barnacles growing on 1-year-old wood in the canal. The highest overall concentrations of metals were found in oysters in the canal. (Copyright (c) 1993 Pergamon Press Ltd.)