Distribution and significance of copper, lead, zinc and cadmium in the Corio Bay ecosystem

Abstract

Levels of copper, lead, zinc and cadmium in sediments, waters and mussels (Mytilus edulis) from Corio Bay (Vic.) were measured on two occasions in 1977. The bay has restricted water exchange with Port Phillip Bay and is known to have received a major input of cadmium. The respective concentrations of copper, lead, zinc and cadmium in the sediments were 2-50,2-2l0,4-398 and up to 12.6 µg/g; in the unfiltered waters, I .5-25, <0.4-11, 3.9-67 and 0.11-5.6 µg/l; and in the mussels, 4.8-21. 1.2-9.7, 105-110 and 9.8-53 µg/g on a dry weight basis.

The observed levels of heavy metals are compared with threshold levels reported in the literature as causing significant interference with growth of phytoplankton and nutrient cycling by bacterial processes.