Summary of environmental impacts

#### SHELLFISH

##### Contaminant Loads

Deployed oysters and mussels have been used to assess the impacts of several outfalls in NSW. These have usually been associated with the larger outfalls in the Sydney and Newcastle regions. Diversion of sewage from nearshore to offshore areas in Sydney resulted in a significant drop in the concentrations of organochlorine compounds in oysters deployed near the shoreline outfalls (Scanes 1996). In mussels deployed near the new deep ocean outfall at Malabar, the outfall was suggested to be a significant source of chromium, arsenic, silver and lead (Andrijanic 1993). Outfalls on the Kurnell peninsula were also found to be a significant source of trace metals in deployed mussels (AWT 1994). In contrast, no outfall effects were found for contaminants in oysters deployed near the Newcastle outfalls (Ajani and Wansborough 1996).

(Impac_6) Last updated May 2000