Environmental impact of chemical wastes produced by the salmon aquaculture industry

The rapid expansion of the salmon aquaculture industry in the last decade and the intentional and unintentional use of many chemicals have resulted in wastes that may have a direct environmental impact. Thus. methods and criteria are required to assess the environmental impact of these chemicals, in particular to identify the hazards and assess the risks of their uses. We describe a project in progress that is aimed at identifying the source of chemical wastes of salmon aquaculture in the Bay of Fundy, the quantities released, their distribution, and environmental fate. The project is also concerned with the effects of chemical wastes on important fisheries resources. Laboratory studies indicated that chemicals used in the treatment of sea-lice infestations are lethal to shrimp and lobsters. Lobsters exposed to sublethal concentrations of one of these chemicals, azamethipohos, had decreased reproductive success compared to control lobsters. However. more information is required to estimate the associated risk to wild populations of lobster and shrimp.