EFFECTS OF CONTAMINANTS FROM CHROMATED COPPER ARSENATE-TREATED LUMBER ON BENTHOS

The fine particle fraction of sediments collected near bulkheads made of chromated copper arsenate (CCA)-treated wood had elevated concentrations of the three chemicals. These decreased with distance from the bulkhead. Although the concentrations in the fine particle fraction of these sediments were quite high, the sediments had less than 1% fine particles, being primarily sand. Concentrations of the three contaminants in benthic organisms adjacent to the bulkhead were also elevated and decreased with distance. However, toxicity tests with the sediments adjacent to the bulkhead did not reveal consistent toxicity, probably because the overall concentration of metals was low. On the other hand, benthic community analysis revealed that there were reduced species richness, total numbers of organisms, and diversity in the sediments adjacent to the bulkheads, compared to reference sediments with lower metal concentrations.