Since the analyses were initiated in the late 1990s, no residues of illegal drugs have been found in samples of farmed fish, and the level of approved drugs and other undesirable substances analysed has been below internationally accepted limits in all species of farmed fish investigated. The same trend was observed through analyses of drug residues in farmed fish from 2010. The most recent monitoring results (2009) show low levels of organic contaminants and heavy metals in farmed fish fillets compared to the EU’s upper limits for the analysed compounds, where such limits exist. The surveillance activities document good seafood safety with respect to drug residues and other undesirable substances in farmed fish.
On behalf of the Norwegian Food Safety Authority, NIFES has under its surveillance programme for the monitoring of undesirable substances in farmed fish determined the content of residues of illegal drugs, legally used veterinary medicines and other undesirable substances. In 2009 the following species were included in the surveillance programme: salmon, trout, rainbow trout, Arctic char, turbot, halibut, cod and saithe. Analyses were carried out on individual or pooled samples of a total of 12,676 farmed fish harvested that year. The levels of undesirable substances in fillets of farmed fish reflect to a large extent the feed given to the fish. To ensure the safety of the fish feed, the Norwegian Food Safety Authority has its own monitoring programme for undesirable substances in feed and feed materials.
Drug residues
In 1998, Norway introduced a comprehensive control system to ensure that farmed fish for consumption do not contain residues of illegal pharmaceuticals or residues of legal pharmaceuticals in concentrations above internationally accepted levels. The system is based on the control and registration of the use of pharmaceuticals, enforcement of withdrawal times to ensure that fish are not slaughtered until a certain fixed period of time has elapsed after administration of the pharmaceutical, and analytical control of residues of pharmaceuticals in the farmed fish. The Norwegian system for control and analysis of pharmaceuticals and environmental pollutants in farmed fish complies with EU regulations, and is regularly monitored and revised by EFTA’s monitoring body ESA. The analytical control of residues of pharmaceuticals in farmed fish forms part of the surveillance programme for monitoring of undesirable substances.
In the 2010 monitoring programme, samples of fillets of farmed fish to be analysed for illegal pharmaceuticals were collected on farm sites by official inspectors. To test for levels of legally applied pharmaceuticals, samples of marketable fish were collected in slaughtering or packing facilities. The range of the analysis included approved delousing agents and antibiotics, as well as illegal drugs. As in previous years, the level of approved drugs was well below internationally accepted limits. However, residues of the illegal drug chloramphenicol just above the detection limit were found in one sample. The possibility that the result may be due to a contamination during sampling is pursued by the Norwegian Food Safety Authority.
Residues of other undesirable substances
The results from the monitoring of undesirable substances in farmed fish for 2009 show that the levels of organic contaminants and heavy metals in farmed fish fillets are low compared with the EU’s upper limits, where such limits exist. Organic compounds such as dioxins and dioxin-like PCBs are fat-soluble environmental pollutants found primarily in fatty fish. The total content of dioxins and dioxin-like PCBs in the samples analysed was slightly above 1/10 of the EU’s upper limit. Mercury is an environmental pollutant which is absorbed and stored in both fatty and low-fat fish. The average level of mercury in all of the samples analysed was slightly less than 1/10 of the EU’s upper limit. In order to maintain food safety, it is important to monitor the level of these substances in fish for consumption.
- Monitoring programme for residues of therapeutic agents, illegal substances, pollutants and other undesirable substances in farmed fish. Report 2009
- The report with the 2010 monitoring results will be published during summer 2011.