Salmon is toxic
Pro Research Analysisby 
Searched over 200M research papers
Consensus Meter
Toxicity in Salmon: An Overview of Recent Research
Introduction to Salmon Toxicity Concerns
Salmon, a popular and nutritious fish, has been the subject of various studies investigating potential toxic contaminants. These studies have explored different sources of toxicity, including environmental pollutants, heavy metals, and harmful algal blooms. This article synthesizes recent research findings on the toxicity of salmon, focusing on farmed and wild varieties.
Toxic Contaminants in Farmed Salmon
Organic Contaminants
Research has shown that farmed salmon often contain higher levels of persistent organic pollutants compared to wild salmon. These contaminants include polychlorinated biphenyls (PCBs), dioxins, and chlorinated pesticides, which are significantly higher in farmed salmon, particularly those raised in Europe. Additionally, polybrominated diphenyl ethers (PBDEs) have been found in higher concentrations in farmed salmon compared to their wild counterparts, with European farm-raised salmon showing the highest levels.
Heavy Metals
A study on Turkish farmed salmon revealed the presence of various toxic metals, including mercury (Hg), cadmium (Cd), and lead (Pb). However, the levels of these metals were found to be below the permissible values set by health authorities, indicating that the contamination in these fish fillets is insignificant and poses negligible carcinogenic risk.
Environmental and Chemical Toxicity
Uranium Exposure
Exposure to uranium (U) in aquatic environments has been shown to affect Atlantic salmon. A study using depleted uranium (DU) as a model found that uranium exposure led to significant changes in gene expression related to mitochondrial function, oxidative stress, and cellular homeostasis. However, no significant physiological changes were observed, suggesting that while uranium can induce early toxicological mechanisms, its overall impact may be limited.
Selenium Toxicity
Selenium (Se), depending on its chemical form, can be both essential and toxic. Research on Atlantic salmon fed with diets fortified with organic and inorganic selenium showed that high levels of inorganic selenium (selenite) led to reduced growth, increased oxidative stress, and disturbances in lipid metabolism. Organic selenium (selenium-methionine) was found to be less toxic but still caused some adverse effects at high concentrations.
Algal Blooms and Shellfish Toxins
Paralytic Shellfish Poisoning (PSP)
Blooms of the dinoflagellate alga Alexandrium fundyense, which produces toxins causing paralytic shellfish poisoning (PSP), have been linked to substantial mortalities in Atlantic salmon. However, analyses of muscle tissues and viscera from affected salmon indicated that the fish would not pose a health hazard if consumed, despite the presence of PSP toxins in the surrounding environment.
Toxicity from Urban Pollutants
Polycyclic Aromatic Hydrocarbons (PAHs)
Juvenile Chinook salmon exposed to polycyclic aromatic hydrocarbons (PAHs) showed significant reductions in growth and alterations in plasma chemistry and lipid metabolism. These effects were similar to those observed in fish experiencing starvation, indicating that PAHs can induce a state of "toxicant-induced starvation".
6PPD-Quinone
The breakdown product of a common tire rubber additive, 6PPD-quinone, has been identified as highly toxic to coho salmon, causing acute toxicity and mortality. However, studies on Atlantic salmon and brown trout showed no significant adverse effects, highlighting species-specific differences in sensitivity to this contaminant .
Conclusion
The research indicates that while farmed salmon may contain higher levels of certain contaminants compared to wild salmon, the overall risk to human health from these contaminants is generally low. Environmental pollutants such as uranium and selenium can induce toxicological responses in salmon, but their impact varies depending on the chemical form and concentration. Algal blooms and urban pollutants also pose significant risks, particularly to specific salmon species. Continued monitoring and research are essential to fully understand and mitigate the risks associated with consuming salmon.
Sources and full results
Most relevant research papers on this topic
The Health Benefits of Eating Salmon
Paralytic shellfish toxins in zooplankton, mussels, lobsters and caged Atlantic salmon, Salmo salar, during a bloom of Alexandrium fundyense off Grand Manan Island, in the Bay of Fundy
Hepatic transcriptomic profiling reveals early toxicological mechanisms of uranium in Atlantic salmon (Salmo salar)
Farmed Turkish salmon: Toxic metals and health threat
Global assessment of polybrominated diphenyl ethers in farmed and wild salmon.
Sensitivity and toxic mode of action of dietary organic and inorganic selenium in Atlantic salmon (Salmo salar).
Altered growth and related physiological responses in juvenile Chinook salmon (Oncorhynchus tshawytscha) from dietary exposure to polycyclic aromatic hydrocarbons (PAHs)
Flesh quality of market-size farmed and wild British Columbia salmon.
Acute Toxicity Testing of the Tire Rubber–Derived Chemical 6PPD‐quinone on Atlantic Salmon (Salmo salar) and Brown Trout (Salmo trutta)
Acute Toxicity of 6PPD‐Quinone to Early Life Stage Juvenile Chinook (Oncorhynchus tshawytscha) and Coho (Oncorhynchus kisutch) Salmon
Try another search
What are the ethical considerations in the application of technology in mental health care and psychological interventions?
research design
Should I eat more eggs if I want to live forever?
research methods
What is the cultural impact of global streaming services?
Self-esteem and job satisfaction among the academic staff in higher education