This study of leaching examined the following variables: CCA loading; marine versus laboratory exposure and length of submergence. Blocks of Pinus sylvestris were treated to a range of nominal retentions from 15 to 50 kg/m³. Each block was then divided into three cubes and all transverse faces were sealed. All cubes were allowed to fix at ambient temperature for a minimum of one week. One set of end cubes were submerged at Sagres, Portugal; the other end cubes were submerged in seawater in a laboratory system to provide a comparison of marine and laboratory leaching. Marine blocks were removed at periods of 1, 6, 12 and 18 months. Laboratory blocks were removed at 1, 2, 4 and 6 months. The middle cube was analysed using atomic absorption spectroscopy to provide the initial preservative loading for each block. After the submergence period end cubes were analysed to determine the amount of preservative remaining. Results showed that there was a time-related decrease in the flux of all metals from the cubes exposed in the laboratory. Leaching of chromium and arsenic was negligible in the marine environment, but copper losses showed a similar time-related pattern of flux, though it was lower than that observed in the laboratory. Measurement of the metals in the laboratory seawater confirmed that copper and arsenic were leached in excess of chromium.

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