Chemical use in salmon aquaculture: A review of current practices and possible environmental effects

The World Wildlife Fund is facilitating a dialogue on impacts of salmon aquaculture. The goal of the dialogue is to establish the state of knowledge in seven subject areas associated with the industry: benthic impacts, nutrient loading, escapees, chemical inputs, diseases, feeds and social issues and to establish international standards for salmon aquaculture practices. Chemical inputs from salmon aquaculture include antifoulants, antibiotics, parasiticides, anaesthetics and disinfectants. The use and potential effects of these compounds are herein summarized for the four major salmon producing nations: Norway, Chile, UK and Canada. Regulations governing chemical use in each country are presented as are the quantities and types of compounds used. The problems associated with fish culture are similar in all jurisdictions, the magnitude of problems is not and the number of compounds available to the fish farmer varies from country to country. Unfortunately, the requirement to publically report chemical use is inconsistent among countries. Chemical use data are available from Norway, Scotland and parts of Canada. The government of Chile and some Canadian provinces, while requiring that farmers report disease occurrence, compounds prescribed and quantities used, do not make this information readily available to the public. The fact that these data are available from regulatory agencies in Scotland and Norway adds pressure for other jurisdictions to follow suit. Data such as these are essential to planning and conducting research in field situations.