Canned and pouched tuna and large predatory fish — food safety profile

What is this product?

Canned and pouched tuna — along with other large predatory fish (swordfish, shark, king mackerel, tilefish, orange roughy, ahi/bigeye tuna, marlin) — is the primary dietary pathway for methylmercury exposure in the United States. Methylmercury is not a manufacturing contaminant or additive; it is a naturally occurring environmental contaminant that biomagnifies up marine food chains with dramatic efficiency, accumulating at approximately 10× per trophic level. A large predatory fish like swordfish that has consumed hundreds of smaller fish over decades of life will carry mercury concentrations hundreds of times higher than the phytoplankton at the base of the chain. Tuna — one of the most consumed fish proteins in the US — spans a wide range of mercury concentrations depending on species: canned light tuna (primarily skipjack) averages approximately 0.128 ppm mercury, while canned albacore/white tuna averages approximately 0.350 ppm — nearly three times higher. At the upper end, swordfish averages approximately 0.995 ppm, with individual fish sometimes exceeding 1.5 ppm. The regulatory and public health response to mercury in fish has focused on guidance rather than prohibition because fish also provides critical nutritional benefits — high-quality protein, omega-3 fatty acids (DHA and EPA) that are essential for fetal and infant brain development, selenium, and iodine. FDA and EPA co-issue fish consumption advice specifically calibrated to preserve these nutritional benefits for the populations most at risk from mercury while managing the neurodevelopmental risk. The 2024 FDA/EPA fish advice establishes three tiers: 'Best Choices' (eat 2–3 servings per week, includes canned light/skipjack tuna), 'Good Choices' (eat 1 serving per week, includes canned albacore/white tuna and yellowfin), and 'Choices to Avoid' (swordfish, shark, king mackerel, Gulf tilefish, orange roughy, marlin, bigeye/ahi tuna). This guidance applies specifically to pregnant women, breastfeeding mothers, and young children — the populations for whom methylmercury neurodevelopmental risk is greatest. For non-pregnant adults, the risk-benefit calculation shifts substantially in favor of consumption, particularly for lower-mercury species. BPA in can linings is a secondary concern for canned tuna — the epoxy lining in steel cans is typically BPA-based, and BPA migration into acidic or fatty food matrices (including tuna packed in oil) has been documented.

What's in it

Click any compound name for its full safety profile, regulatory consensus, and exposure data.

Who's most at risk

• Pregnant Women — Fetal exposure via placental transfer; developing endocrine systems of fetus
• Children — Higher food-to-body-weight ratio, developing organ systems

How to use it more safely

• Limit consumption to 2-3 servings per week due to mercury content
• Check expiration dates; do not consume expired products
• Ensure cans/pouches are intact with no swelling or damage before opening

Red flags — when to walk away

• Consuming swordfish, shark, king mackerel, Gulf tilefish, orange roughy, marlin, or bigeye/ahi tuna regularly — especially during pregnancy or when feeding young children — FDA/EPA 'Choices to Avoid' species for pregnant women and young children. These fish have average mercury concentrations that make even occasional consumption problematic during pregnancy. Swordfish at ~0.995 ppm average means a single typical serving delivers substantial mercury load against a tight weekly budget. Individual fish can substantially exceed the species average.
• Consuming albacore (white) canned tuna more than once per week during pregnancy — Albacore tuna averages ~0.350 ppm mercury — nearly 3× higher than skipjack canned light tuna. FDA/EPA guidance places albacore in the 'Good Choices' tier limited to 1 serving per week for pregnant women. Exceeding this frequency with albacore accumulates mercury exposure above what the reference dose permits on a consistent basis.

Green flags — what to look for

• Canned light tuna (skipjack); pouch packaging (BPA-free construction); sardines, anchovies, or wild Alaskan salmon as primary seafood protein; brand in FDA/EPA 'Best Choices' tier — Skipjack/light canned tuna at FDA/EPA-recommended frequencies (2–3 servings/week) provides meaningful omega-3 and protein benefit within safe mercury limits for pregnant women. Pouches eliminate the BPA-from-can-lining pathway. Sardines and anchovies are arguably the optimal risk-benefit seafood — very low on the food chain (minimal mercury), very high omega-3, and widely available.

Safer alternatives

• Canned light tuna or skipjack — Lower mercury levels than albacore; safer for frequent consumption
• Canned salmon or sardines — Lower mercury, higher omega-3s, lower environmental concern
• Fresh or frozen smaller fish species — Lower bioaccumulated mercury; better portion control

Frequently asked questions