Concentrations of elements in a marine food chain cultured in sewage wastewater

The use of domestic wastewater as a source of nutrients for aquaculture operations is becoming increasingly attractive. Studies were conducted to learn which elements in such effluents are absorbed by aquatic species and whether the magnitude of absorption may constitute a hazard to consumers. Seaweed, clams, oysters, lobsters, and flounder cultured in secondary wastewater were analyzed. Some organisms accumulated significant levels of cadmium, copper, lead, and zinc. Accumulation of elements is shown to be considerable; monitoring metal concentrations in domestic or industrial wastewater prior to reuse is recommended.