Norwegian salmon toxic
Pro Research Analysisby 
Searched over 200M research papers
Toxicity in Norwegian Farmed Salmon: An Overview
Contaminant Levels in Norwegian Farmed Salmon
Dioxins and PCBs in Norwegian Salmon
Norwegian farmed Atlantic salmon has been under scrutiny for its levels of environmental pollutants such as dioxins and polychlorinated biphenyls (PCBs). A comprehensive study spanning from 1999 to 2011 revealed a significant decrease in the levels of mercury, arsenic, dioxins, dioxin-like PCBs, and DDT in salmon fillets over the years1. However, the levels of cadmium, lead, and several organochlorine pesticides were too low to establish a trend. Despite the reduction, the sum of dioxins and dioxin-like PCBs remains the limiting factor for safe consumption, with tolerable weekly intake levels allowing for up to 1.3 kg of salmon per week1.
Comparison with Other Regions
A comparative study analyzed farmed Atlantic salmon from Maine, eastern Canada, and Norway, alongside wild Alaskan Chinook salmon. It was found that Norwegian farmed salmon had higher concentrations of PCBs and WHO PCB TEQs compared to wild Alaskan salmon. Interestingly, organically farmed Norwegian salmon exhibited the highest PCB concentrations among the samples, suggesting that organic farming practices do not necessarily equate to lower contaminant levels2.
Radionuclides in Norwegian Salmon
Natural and Anthropogenic Radionuclides
Norwegian farmed salmon has also been tested for radionuclides, both natural and anthropogenic. The only anthropogenic radionuclide detected was 137Cs, found at low levels. Natural radionuclides such as 40K were present at higher levels, but overall, the radionuclide levels in farmed salmon were comparable to or lower than those in other North Atlantic fish species. The estimated radiation dose from consuming these salmon is very low, indicating minimal risk from radioactivity3.
Disease and Parasite Concerns
Amoebic Gill Disease and Sea Lice
Amoebic gill disease (AGD) and sea lice are significant issues in Norwegian salmon farming. Freshwater treatments are commonly used, but their effectiveness can vary based on water chemistry. The use of oxidative disinfectants like hydrogen peroxide is being explored, although their interactions with water chemistry and organic loads need further study4. Additionally, the rise of resistance in salmon lice to common treatments has led to increased use of non-medicinal methods, such as cleaner fish, to control these parasites7.
Metazoan Parasites
Wild salmon in Norway are hosts to various metazoan parasites, some of which, like Lepeophtheirus salmonis and Eubothrium sp., also affect farmed salmon, causing economic losses. The presence of these parasites in wild populations poses a risk of transmission to farmed salmon, complicating disease management efforts9.
Heavy Metals and Other Elements
Toxic and Essential Elements
Surveys conducted between 2012 and 2015 in the Mausund area of Norway analyzed the concentrations of various toxic and essential elements in local seafood, including salmon. Elevated levels of cadmium were found in edible crabs, but the study did not indicate significant contamination in salmon from nearby farms. This suggests that local geogenic sources are not a major cause of high metal values in the biota5.
Conclusion
Overall, while the levels of certain contaminants in Norwegian farmed salmon have decreased over the years, issues with dioxins, PCBs, and parasites remain. The presence of radionuclides is minimal and poses a low risk to consumers. Continuous 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 CitedPCBs, 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 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 StudyFreshwater 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 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 StudyInteractions between wild and cultured Atlantic salmon: a review of the Norwegian experience
Norwegian salmon farming has increased the proportion of cultured salmon in small populations, leading to potential ecological effects and increased fishing pressure on wild salmon.
Literature ReviewHighly 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 JournalA critical limit for acid neutralizing capacity in Norwegian surface waters, based on new analyses of fish and invertebrate responses
A critical limit of acid neutralization capacity (ANC) of 20 equiv./l is suggested as the tolerance level for Norwegian surface waters, with Atlantic salmon being the most sensitive and brown trout being useful indicators for lakes.
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.
Salmonella 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 CitedTry another search
What are the latest findings on the health impacts of chronic sleep deprivation?
What are the implications of quantum entanglement for communication?
obesity
What are the implications of the paleo and whole30 diets for health and disease prevention?
parasocial interaction
What are the best treatments for rhuematoid arthritis?