Norway salmon toxic
Pro Research Analysisby 
Searched over 200M research papers
Toxicity in Norwegian Farmed Salmon: An Overview
Introduction to Contaminant Levels in Norwegian Farmed Salmon
Norwegian farmed Atlantic salmon (Salmo salar) has been under scrutiny for potential toxic contaminants. Over a 13-year period from 1999 to 2011, significant efforts were made to monitor and analyze the levels of various contaminants in these fish. The primary contaminants of concern include dioxins, PCBs, heavy metals, and organochlorine pesticides1.
Decrease in Contaminant Levels Over Time
Dioxins and PCBs
The levels of dioxins and dioxin-like PCBs in Norwegian farmed salmon have shown a notable decrease over the years. By 2011, the levels were low enough to allow for the consumption of up to 1.3 kg of salmon per week without exceeding the tolerable weekly intake1. This reduction is significant as dioxins and PCBs are known for their potential to cause chronic health issues in humans.
Heavy Metals and Pesticides
Similarly, the levels of heavy metals such as mercury and arsenic, as well as organochlorine pesticides like DDT, have also decreased. However, the levels of cadmium, lead, and several other pesticides were too low to establish clear trends1. This overall reduction in contaminants suggests improved practices in salmon farming and feed production.
Radionuclides in Farmed Salmon
A comprehensive survey of radionuclides in Norwegian farmed salmon revealed the presence of both natural and anthropogenic radionuclides. The only anthropogenic radionuclide detected was 137Cs, found at low levels. Natural radionuclides like 40K were present at higher levels, but the overall risk from radioactivity in farmed salmon remains very low3.
Chemical Use and Environmental Impact
Antifoulants, Antibiotics, and Disinfectants
The use of chemicals in salmon aquaculture, including antifoulants, antibiotics, parasiticides, anaesthetics, and disinfectants, varies by country. Norway, along with Scotland and parts of Canada, has regulations requiring public reporting of chemical use, which aids in monitoring and mitigating environmental impacts6.
Resistance to Treatments
The salmon louse (Lepeophtheirus salmonis) has developed resistance to several chemotherapeutants, including hydrogen peroxide. This resistance complicates the management of salmon lice, a significant issue for the industry. Non-medicinal methods and the use of cleaner fish have been increasingly adopted to combat this problem7 9.
Health Risks and Safety
Salmonella in Fish Feed
Salmonella is a concern in fish feed, but the prevalence in Norwegian fish feed is low. The risk of transmission to humans via farmed salmon is minimal, given the low concentrations of Salmonella in the feed and the stringent monitoring practices in place8.
Comparison with Other Regions
Farmed salmon from Norway, Maine, and eastern Canada have been compared for contaminant levels. Norwegian salmon, particularly those organically farmed, showed higher concentrations of PCBs and dioxin-like PCBs compared to wild Alaskan salmon. This highlights the need for continued efforts to reduce contaminant levels in farmed salmon4.
Conclusion
Overall, the levels of toxic contaminants in Norwegian farmed salmon have decreased over the years, making it safer for consumption. However, challenges such as chemical resistance in salmon lice and the presence of radionuclides and Salmonella in fish feed require ongoing attention. Continued monitoring and improved farming practices are essential to ensure the safety and sustainability of Norwegian farmed salmon.
Sources and full results
Most relevant research papers on this topic
Contaminant levels in Norwegian farmed Atlantic salmon (Salmo salar) in the 13-year period from 1999 to 2011.
Norwegian farmed Atlantic salmon's contaminant levels generally decreased between 1999 and 2011, allowing safe consumption of up to 1.3kg per week, with dioxins and dioxin-like PCBs being the limiting factor.
Observational Study
Rigorous Journal
Highly CitedFreshwater treatment of amoebic gill disease and sea-lice in seawater salmon production: Considerations of water chemistry and fish welfare in Norway
Freshwater treatment for amoebic gill disease and sea lice in Norwegian Atlantic salmon aquaculture is variable, with varying efficacy and costs, and maintaining water quality during treatments is crucial for optimal fish welfare and treatment efficacy.
Highly CitedNatural and anthropogenic radionuclides in Norwegian farmed Atlantic salmon (Salmo salar).
The risk associated with radioactivity in farmed Atlantic salmon is very low, with levels comparable to or lower than those found in other fish species in the North Atlantic Ocean.
Observational StudyPCBs, PCDD/Fs, and organochlorine pesticides in farmed Atlantic salmon from Maine, eastern Canada, and Norway, and wild salmon from Alaska.
Farmed Atlantic salmon from Maine and eastern Canada have higher PCB concentrations than wild Alaskan Chinook salmon, with organically farmed Norwegian salmon having the highest concentrations, suggesting skin removal does not protect consumers from health risks associated with farmed salmon consumption.
Highly CitedToxic and essential elements in seafood from Mausund, Norway
Elevated levels of Cd in edible crabs in Mausund, Norway, indicate local geogenic sources are not a major cause of high levels in local biota.
Observational StudyChemical use in salmon aquaculture: A review of current practices and possible environmental effects
Salmon aquaculture uses a variety of chemicals, with Norway, Chile, UK, and Canada showing similar environmental impacts, but public reporting of chemical use is inconsistent among countries.
Highly CitedTrends in de-lousing of Norwegian farmed salmon from 2000–2019—Consumption of medicines, salmon louse resistance and non-medicinal control methods
Salmon lice resistance in Norway has declined with the introduction of non-medicinal treatments and cleanerfish, highlighting the importance of avoiding heavy reliance on a few substances to combat ectoparasites.
Observational StudyRigorous JournalSalmonella in fish feed; occurrence and implications for fish and human health in Norway
Salmonella serovars occasionally occur in Norwegian fish feed, but the risk of transmission to humans through fish products is minimal, with no evidence of transmission from fish feed to humans.
Observational StudyHighly CitedFirst report of reduced sensitivity towards hydrogen peroxide found in the salmon louse Lepeophtheirus salmonis in Norway
Reduced sensitivity towards hydrogen peroxide in salmon lice is hereditary, posing a threat to the Norwegian fish farming industry and should be monitored closely.
Highly CitedA report on some metazoan parasites of wild marine salmon (Salmo salar L.) from the west coast of Norway with comments on their interactions with farmed salmon
Copepod Lepeophtheirus salmonis and cestode Eubothrium sp. cause serious economic losses in Norwegian salmon farming, while Anisakis simplex larvae are a well-known problem in wild fisheries.
Try another search
What are the latest findings on the environmental and health impacts of organic versus conventionally produced foods?
What are the benefits of probiotics, and how do I choose the right one?
What are the applications of nanotechnology in medicine and healthcare?
What are the ethical considerations in anthropological research and practice?
prostate cancer
What are the benefits of a plant-based diet?