Is Smoked Salmon High in Mercury? The Definitive Guide

December 12, 2025 •

3 min read

According to the FDA, fresh and frozen salmon has a very low mean mercury concentration of 0.022 ppm, making it one of the safest fish to eat. The question is: does smoking increase these levels, making smoked salmon high in mercury?

Quick Summary

Smoked salmon is not high in mercury, as the smoking process does not affect the fish's low natural mercury content. Potential risks relate to Listeria contamination in cold-smoked varieties and high sodium content, which require consideration for vulnerable groups.

Key Points

Low Mercury: Smoked salmon is a low-mercury fish, consistent with fresh salmon, as the smoking process does not introduce or concentrate mercury.
Listeria Risk: Cold-smoked salmon poses a risk for Listeria bacteria, especially for pregnant women, older adults, and those with weakened immune systems.
High Sodium: The curing process makes smoked salmon significantly higher in sodium than fresh salmon, a concern for individuals on a low-sodium diet.
No Cooking Effect on Mercury: Cooking or smoking does not reduce the mercury content of a fish; it remains in the muscle tissue.
Benefits vs. Risks: For most people, the health benefits of salmon, including Omega-3s, outweigh the minimal mercury risk.
Wild vs. Farmed: Both wild and farmed salmon are low in mercury, though some studies have shown farmed salmon may have slightly lower levels.

Understanding Mercury and How it Gets into Fish

Mercury is a naturally occurring element that enters oceans and waterways through natural events and industrial activities, like burning fossil fuels. Microorganisms convert mercury into methylmercury, a highly toxic form. Fish absorb this compound, which accumulates in their tissue. Bioaccumulation causes methylmercury levels to increase up the food chain, with larger, predatory fish having higher concentrations from eating smaller fish.

Why Salmon Remains a Low-Mercury Choice

Salmon's position low in the marine food chain and its relatively short lifespan are why its mercury content is low. Salmon does not eat as many mercury-containing fish as large predators, such as sharks or swordfish, leading to less mercury accumulation in its muscle tissue. Smoking, which involves curing the fish in salt and exposing it to smoke, does not add mercury. Cooking or processing fish, including smoking, does not significantly reduce the amount of mercury already present. Therefore, because raw salmon is low in mercury, smoked salmon also has low levels.

Is Smoked Salmon High in Mercury? The Verdict

No, smoked salmon is not high in mercury. Health authorities like the FDA and EPA list it as a "Best Choice" or low-mercury fish. A study that tested smoked salmon products showed mercury concentrations were well below safety limits. The health benefits of consuming salmon, specifically its omega-3 fatty acids, often outweigh the minimal risk associated with low mercury content for the general population.

Wild vs. Farmed Salmon Mercury Levels

Research explores mercury levels between wild-caught and farmed salmon, though both are safe and low in mercury. Some studies found that farmed salmon had lower mercury concentrations than wild salmon, possibly due to rapid growth and high lipid content. The diet of farmed fish is controlled, which affects contaminant levels. Both wild and farmed salmon remain excellent, low-mercury choices.

A Comparison of Fish Mercury Levels

To put salmon's low mercury content in perspective, consider the varying levels across different seafood. Below is a comparison using FDA data, showing why salmon is safe.


Species	Mercury Mean (ppm)	FDA/EPA Category	Notes
Swordfish	0.995	Avoid	Large, predatory fish
Shark	0.979	Avoid	Large, predatory fish
Canned Albacore Tuna	0.350	Good Choice	Higher than canned light tuna
Mahi Mahi	0.178	Good Choice	Also known as Dolphinfish
Cod	0.111	Best Choice
Canned Light Tuna	0.126	Best Choice	Includes skipjack
Salmon (Fresh/Frozen)	0.022	Best Choice
Shrimp	0.009	Best Choice

Beyond Mercury: Other Risks and Concerns with Smoked Salmon

While mercury is not a major concern, other factors with smoked salmon must be considered. The processing method can introduce different risks, primarily related to bacteria and high sodium levels.

Listeria Risk in Cold-Smoked Varieties

Cold-Smoked Salmon: This variety is not cooked during the smoking process, only cured and smoked at low temperatures. This makes it susceptible to contamination by Listeria monocytogenes, a bacterium that causes listeriosis.
Who is at risk?: Listeriosis is dangerous for pregnant women, newborns, older adults, and individuals with weakened immune systems.
Safety Precaution: Health authorities recommend that vulnerable groups avoid refrigerated cold-smoked salmon unless cooked to an internal temperature of 165°F (74°C). Hot-smoked varieties, which are fully cooked, are generally safer.

High Sodium Content

The curing process for smoked salmon involves a significant amount of salt, resulting in a higher sodium content compared to fresh salmon. Excessive sodium increases the risk of high blood pressure and other cardiovascular issues. People on low-sodium diets should monitor their consumption of smoked salmon.

Conclusion

Smoked salmon is not high in mercury. Salmon, whether wild or farmed, has low mercury levels due to its place in the food web. The smoking process does not add mercury. For most healthy adults, smoked salmon can be a nutritious part of a balanced diet, offering omega-3 fatty acids and protein. However, consumers should be aware of the potential for high sodium and the risk of Listeria with cold-smoked varieties. Vulnerable populations, including pregnant women, should follow health guidelines regarding cold-smoked fish to minimize risks, mainly those not related to mercury. Understanding the true risks and benefits allows the responsible enjoyment of smoked salmon.

Understanding Mercury in Seafood

For a deeper understanding of mercury's effects on seafood, explore information from the U.S. Environmental Protection Agency (EPA), which provides resources on mercury exposure and safe fish consumption.

Frequently Asked Questions

No, smoked salmon does not contain more mercury than fresh salmon. The smoking and curing process does not increase the mercury content, as mercury is stored in the fish's muscle tissue and is not affected by cooking or processing.

While salmon is low in mercury and beneficial for pregnancy, cold-smoked salmon is not recommended for pregnant women unless cooked until steaming hot. This is due to the risk of Listeria contamination, which can cause serious illness in vulnerable populations. Hot-smoked salmon, which is fully cooked, is a safer option.

Both wild and farmed salmon have low mercury levels. Some studies have indicated that farmed salmon may have slightly lower mercury concentrations than wild salmon, possibly due to controlled diets and faster growth. Regardless, both are considered low-mercury choices.

The primary health concerns with smoked salmon relate to its high sodium content due to the brining process and the potential for Listeria contamination in cold-smoked varieties, particularly for at-risk individuals.

For the general population, the low mercury content in salmon makes regular consumption safe, and the health benefits, such as omega-3 fatty acids, are significant. However, it is always best to eat a variety of fish and seafood to balance nutritional intake.

Salmon consistently ranks among the fish with the lowest mercury levels. For example, fresh/frozen salmon has a mean mercury concentration of 0.022 ppm, significantly lower than high-mercury fish like swordfish (0.995 ppm) or shark (0.979 ppm).

If you are pregnant and have eaten cold-smoked salmon, do not panic. The risk of Listeria contamination is low, but you should monitor for symptoms like fever, fatigue, or muscle aches and contact your healthcare provider immediately if they occur.

In addition to Listeria and high sodium, some sources mention potential contaminants like PCBs, particularly in salmon raised near polluted coastlines. However, mercury levels are generally very low, and many health organizations suggest the benefits of eating salmon still outweigh the risks.