Which Salmon Should You Avoid Eating? A Guide to Healthier Choices

November 25, 2025 •

3 min read

According to a 2004 study published in Science, farmed salmon had polychlorinated biphenyl (PCB) concentrations that were, on average, almost eight times higher than in wild salmon. This highlights why being aware of which salmon you should avoid eating is a critical part of making informed food choices.

Quick Summary

The debate over wild-caught versus farmed salmon involves environmental impact, contaminant levels, and nutritional differences. Issues with open-net pen farming, including pollutants and high disease rates, raise concerns. Consumers can make safer choices by understanding the origins and characteristics of the fish they buy.

Key Points

Avoid poorly regulated farmed salmon: Prioritize purchasing wild-caught salmon or farmed varieties from certified closed-containment systems to minimize exposure to contaminants like PCBs and antibiotics.
Choose Alaskan wild salmon: Wild salmon from Alaska, including Sockeye and King, are known for their lower contaminant levels and cleaner habitat, making them a top choice for health and safety.
Check for freshness: Use your senses to determine if salmon is fresh; it should have a mild smell and firm, vibrant-colored flesh. Avoid fish with a strong odor or dull, discolored appearance.
Understand the label: Look for certifications like the Marine Stewardship Council (MSC) for wild fish or the Aquaculture Stewardship Council (ASC) for responsibly farmed options.
Consider canned wild salmon: As a budget-friendly and healthy alternative, canned wild Alaskan salmon is a reliable option with a better safety profile than many farmed choices.
Minimize environmental impact: Avoiding open-net pen farmed salmon helps reduce your impact on marine ecosystems affected by waste, pollution, and disease spread.

Understanding the Differences Between Wild and Farmed Salmon

The majority of salmon consumed globally is farmed, primarily Atlantic salmon. While aquaculture provides a consistent supply, it differs significantly from wild-caught salmon in health, nutrition, and environmental impact. These differences are crucial for determining which salmon should you avoid eating.

The Problems with Open-Net Pen Farmed Salmon

Many issues with farmed salmon stem from open-net pen systems. These practices, particularly where regulations are less strict, negatively affect both the farmed fish and the surrounding environment.

Contamination Risks: High-density pens increase the risk of contaminant accumulation. Studies, like one in 2004, have shown farmed salmon with significantly higher PCB levels than wild salmon. Other pollutants, including dioxins and metals like arsenic, have also been found.
Antibiotic and Pesticide Use: Crowded farm conditions lead to disease and parasite outbreaks, often managed with antibiotics and pesticides. This raises concerns about antibiotic resistance and environmental harm.
Lower Nutritional Profile: While some farmed salmon has high omega-3s, its omega-6 levels can be significantly higher than in wild salmon. Wild salmon, with its natural diet, offers a more balanced vitamin and mineral content.
Unsustainable Practices: Salmon feed production can deplete wild fish stocks. Farm waste also causes nutrient pollution and harms ecosystems.

How to Choose Safer, Healthier Salmon

Choosing wisely involves understanding the distinction between wild-caught and farmed salmon.

Best Choices

Wild Alaskan Salmon: Species like Sockeye and Coho from Alaska benefit from regulated fisheries and clean waters, resulting in lower pollutant levels. Look for Marine Stewardship Council (MSC) certification.
Closed-Containment Farmed Salmon: These systems isolate fish from the environment, preventing pollution and disease. Certifications like Aquaculture Stewardship Council (ASC) or Best Aquaculture Practices (BAP) indicate responsible farming.

Options to Consider with Caution

Farmed Atlantic Salmon (Open-Net Pen): This is widely available. While some regions have improved practices, global standards vary, meaning contaminant risks can differ.

Comparison Table: Wild vs. Farmed Salmon


Feature	Wild-Caught Salmon	Open-Net Pen Farmed Salmon
Origin	Natural environments	Controlled environments, often open-net pens
Diet	Natural (krill, shrimp, fish)	Formulated pellets
Contaminants	Lower levels	Historically higher levels
Antibiotics	Not used	Used to combat disease
Nutritional Profile	Leaner, balanced omega ratio	Fattier, potentially higher omega-6
Color	Natural vibrant red-orange	Often artificial coloring
Cost	Generally more expensive	More affordable

Spotting Quality Salmon at the Market

Freshness is also crucial. Use sensory checks to avoid bad salmon:

Smell: Fresh salmon should have a mild, clean, or slightly salty smell, not a strong or unpleasant "fishy" odor. A sour smell indicates spoilage.
Appearance: Look for moist, firm flesh with vibrant color. Avoid brown spots or dryness. The skin should be shiny.
Texture: Fresh flesh is firm and springs back when pressed. Mushy or slimy texture indicates spoilage.

Conclusion: Making the Right Choice for Your Plate

When considering which salmon should you avoid eating, poorly regulated, open-net farmed varieties are the primary concern due to potential contaminants, less balanced nutrition, and environmental impact. Wild-caught salmon, especially from sources like Alaska, is generally the safest and healthiest option. Checking labels, certifications, and freshness indicators helps you choose wisely. Canned wild Alaskan salmon is a good, budget-friendly alternative.

Authoritative Source Link

For additional detailed information on seafood safety and sourcing, you can consult the Environmental Working Group's comprehensive report on contaminants in farmed salmon: EWG Report on PCBs in Farmed Salmon.

Frequently Asked Questions

No, not all farmed salmon is necessarily bad, but there are significant differences. Open-net pen farmed salmon, particularly from less regulated regions, has been linked to higher levels of contaminants like PCBs and a less favorable nutritional profile. Responsibly farmed salmon from closed-containment systems is a safer alternative.

Wild salmon are generally considered healthier because they have a natural diet and live in less crowded, cleaner conditions. This results in lower levels of contaminants, a more balanced ratio of omega-3 to omega-6 fatty acids, and a richer nutritional profile compared to their open-net pen farmed counterparts.

PCBs, or polychlorinated biphenyls, are synthetic industrial chemicals that have been linked to potential health issues, including cancer. They can accumulate in the fatty tissue of fish. Historically, farmed salmon have shown higher PCB levels due to the fat-rich fishmeal used in their feed.

The use of antibiotics varies by country and farm. Due to the high-density nature of many open-net pens, antibiotics are often used to prevent and treat disease outbreaks. While some countries, like Norway, have reduced their use, antibiotic contamination and potential resistance remain a concern.

Check for a firm, moist texture and a vibrant pink or red-orange color. The fish should have a mild, ocean-like smell, not a strong 'fishy' or sour odor. Avoid any fillets that look dull, discolored, or have brown spots or slimy residue.

Yes. Salmon farmed in closed-containment recirculating aquaculture systems (RAS) is considered a more sustainable option. These systems recycle water, minimize waste pollution, and prevent escapes. Look for certifications like ASC or BAP when purchasing farmed salmon.

Yes, if you see Atlantic salmon for sale, it is almost certainly farmed. Due to the endangered status of wild Atlantic salmon populations, there is no longer a commercial wild Atlantic salmon fishery.