A comparison of the bivalve species Donax deltoides and Mytilus edulis as monitors of metal exposure from effluent discharges along the Ninety Mile Beach, Victoria, Australia

Concentrations of As, Cr, Cu, Hg, Mo, Ni, Se and Zn were determined in Donax deltoides and Mytilus edulis from the area of discharge of two shallow, submarine outfalls located on the Ninety Mile Beach, Victoria, Australia. Donax deltoides occurs naturally along the coast whereas M. edulis were transplanted from commercially cultured stocks from Port Phillip Bay, Victoria. Tissue was collected from both species for analysis in autumn and spring 1994. There were no statistically significant differences detected in tissue metal concentrations between the two bivalve species. Tissue concentrations of Mo were found to be significantly elevated in both species collected from the site of a discharge of effluent containing fly-ash wastewaters sourced from coal-fired power stations. Lack of detectable differences in tissue metal concentrations between the two species together with the relative ease of collection of D. deltoides from the sandy intertidal zone provide a good rationale for its use in monitoring programmes in localities where it occurs.