What fish are low in PCBs?

Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that accumulate up the food chain, with levels in some fish thousands of times higher than in water. Knowing what fish are low in PCBs is crucial for making healthier seafood choices and reducing your exposure to these concerning chemicals.

Quick Summary

Choosing smaller fish lower on the food chain, like wild salmon, sardines, and various shellfish, can significantly reduce your PCB exposure. Proper preparation is also key to minimizing intake of these fatty-tissue contaminants.

Key Points

• Choose Smaller Fish: Opt for smaller species like sardines and anchovies, which accumulate fewer PCBs due to their shorter lifespans.

• Embrace Shellfish: Clams, oysters, and shrimp are reliably low in contaminants and provide a safe alternative to finfish.

• Favor Wild Salmon: Wild Alaska salmon is an excellent choice, typically containing significantly lower PCB levels than farmed varieties.

• Trim Away Fat and Skin: Since PCBs are stored in fatty tissues, removing the skin and fat before cooking can reduce your overall intake.

• Diversify Your Diet: By eating a wide variety of seafood, you reduce the risk of concentrating exposure to any single contaminant.

• Check Local Advisories: Always consult local fish consumption guidelines for advisories regarding contaminants in fish from specific lakes and rivers.

The Science Behind PCBs in Fish

PCBs are a group of man-made organic chemicals that were widely used in electrical equipment, plastics, and other products before being banned in the United States in 1979. Despite the ban, they persist in the environment from old equipment leaks, spills, and improper waste disposal. PCBs bind to soil and sediment in aquatic environments and are then absorbed by small organisms. This leads to a process called bioaccumulation and biomagnification, where the concentration of PCBs increases as they move up the food chain, from plankton to small fish, and ultimately to larger, predatory fish and the humans who consume them.

PCBs are fat-soluble, meaning they accumulate primarily in the fatty tissues of fish. This is a critical factor when choosing seafood, as fatty, predatory fish that live longer tend to have higher concentrations of PCBs. Understanding this process is the first step toward making informed decisions about which fish to eat to minimize your risk.

What Fish Are Low in PCBs?

To find fish with lower PCB levels, the general rule is to choose smaller, younger fish and those lower on the food chain. These species have had less time and fewer opportunities to accumulate contaminants. Shellfish are also generally excellent low-contaminant choices.

Recommended low-PCB fish species:

• Wild Alaska Salmon: Often cited as a better choice than farmed salmon due to its diet and habitat, wild salmon generally contains lower PCB levels.
• Sardines and Anchovies: These small, oily fish are low on the food chain and reproduce quickly, meaning they don't have time to build up significant levels of mercury or PCBs.
• Shrimp: These are bottom-dwelling shellfish that are consistently reported to have very low levels of contaminants.
• Oysters and Mussels: Like other bivalves, oysters and mussels tend to be very low in contaminants and are excellent seafood options.
• Tilapia and Catfish (Farmed): Farmed freshwater fish like tilapia and catfish are typically fed a controlled diet that can limit their exposure to PCBs found in some wild forage fish.
• Pacific Cod: This whitefish is a lean protein source that is also considered a low-contaminant option.
• Pollock (Wild Alaska): Wild Alaskan Pollock has a lean nutritional profile and is known for its low mercury and low contaminant content.

Shellfish: A Smart Low-PCB Choice

For those concerned about PCBs, shellfish often represent a very safe and healthy choice. Species like shrimp, clams, oysters, and scallops are bottom-feeders but their physiology and shorter lifespans mean they accumulate fewer contaminants compared to large, long-lived predatory fish. The California Office of Environmental Health Hazard Assessment (OEHHA) explicitly recommends shellfish as a low-mercury option and notes that while PCBs accumulate in fat, removing internal organs from crab and lobster can help minimize exposure.

A Note on Wild vs. Farmed Fish

The distinction between wild and farmed fish can be important when considering PCB levels. Historically, farmed fish, particularly salmon, had higher PCB levels due to the fish oil used in their feed. However, the Global Salmon Initiative and other sources report that advances in feed composition, which now includes more plant-based ingredients, have led to farmed salmon containing significantly lower levels of PCBs compared to wild salmon. Always check the source and production methods if this is a major concern for you.

What to Avoid: High-PCB Fish

Certain fish species are known to accumulate higher levels of PCBs due to their position at the top of the food chain, their fatty tissue content, or feeding habits. These include large, predatory, and long-lived fish.

Examples of higher-PCB fish:

• Certain Predatory Fish: This includes species like certain types of bass and bluefish, which can have high PCB levels.
• Fatty Bottom Feeders: Some older, larger bottom-feeding fish can accumulate more PCBs from contaminated sediment.
• European Eel and Bream: Studies on farmed fish in certain regions have found elevated levels of PCBs in species like eel and bream, prompting consumption advisories for vulnerable populations.

How to Further Reduce PCB Exposure When Eating Fish

Beyond choosing low-PCB fish, you can take additional steps to minimize your intake of contaminants, especially with wild-caught varieties from potentially polluted waters.

1. Trim Fat and Skin: PCBs concentrate in the fat and skin of fish. Removing these parts before cooking can significantly reduce the amount of PCBs consumed.
2. Use Healthy Cooking Methods: Bake, broil, or grill fish on an elevated rack to allow fat and juices to drain away. Discard any drippings and avoid using them in sauces or soups.
3. Diversify Your Seafood Choices: Eat a variety of different fish and shellfish species to minimize exposure to any one particular contaminant source.
4. Follow Local Advisories: Pay attention to fish consumption advisories issued by local and state health departments, especially for fish caught in specific lakes, rivers, or coastal areas.

PCB and Fish Comparison Table

Fish Category	Example Species	PCB Level (General Trend)	Omega-3s	Mercury Level	Key Takeaway
Low PCB	Wild Alaska Salmon	Lower than farmed	High	Very Low	Excellent choice for omega-3s.
Low PCB	Sardines, Anchovies	Very Low	High	Very Low	Safe, sustainable small fish.
Low PCB	Shrimp, Clams, Oysters	Very Low	Low	Very Low	Shellfish are reliably low in PCBs.
Low PCB	Farmed Catfish, Tilapia	Very Low	Medium	Very Low	Monitored diets control contaminants.
High PCB Risk	Eel, Bream (Freshwater)	Higher, species-dependent	Varies	Varies	Vulnerable to bioaccumulation.
High PCB Risk	Bluefish, Striped Bass	High (Predatory)	Medium	Varies	Accumulates PCBs as a predator.
Variable	Farmed Salmon (Old)	Higher than wild (historically)	Very High	Very Low	Modern practices have reduced levels.

Conclusion

While PCBs are a lasting environmental concern, consumers can make informed choices to significantly reduce their exposure through seafood. The most effective strategy is to select smaller, younger fish lower on the food chain and to include low-contaminant shellfish in your diet. Wild Alaska salmon, sardines, shrimp, and oysters are among the best choices. Pairing smart seafood selection with proper preparation—such as trimming fat and grilling—provides the best path to enjoying the health benefits of fish while minimizing the risks of contaminants. By staying aware of local advisories and diversifying your seafood intake, you can confidently navigate the waters of safe fish consumption.

For more information on the history and health effects of PCBs, visit the U.S. Environmental Protection Agency's website.

Frequently Asked Questions

Why are some fish higher in PCBs than others?

PCBs are fat-soluble and accumulate through the food chain. Larger, older, and more predatory fish higher on the food chain tend to have higher concentrations, as they consume more contaminated prey and have more time to accumulate the chemical in their fatty tissues.

Does cooking fish reduce PCB levels?

Cooking does not destroy PCBs. However, proper cooking methods can help. Since PCBs are stored in fat, trimming fat and skin and cooking on a rack to allow fat to drain away can help reduce your intake.

Are farmed fish always higher in PCBs than wild fish?

Not necessarily. While historically true, modern farmed fish, particularly salmon, are fed monitored, plant-based diets which have led to lower PCB levels. Always check the sourcing and modern production practices.

How can I find out about local fish advisories for PCBs?

You should check with your state's health department or environmental protection agency. They publish specific consumption advisories for local lakes, rivers, and coastal waters based on contaminant levels.

Is it safe for pregnant women to eat fish with PCBs?

Vulnerable populations, including pregnant women, nursing mothers, and young children, are more susceptible to the effects of contaminants. They should strictly follow fish consumption advisories and choose fish low in both mercury and PCBs.

Can PCBs affect my health?

High-level exposure to PCBs has been linked to various health effects, including potential impacts on the immune, reproductive, and nervous systems, and is considered a probable human carcinogen by the EPA.

What is bioaccumulation?

Bioaccumulation is the process by which persistent contaminants like PCBs build up over time in the fatty tissues of organisms. Biomagnification is the subsequent increase in concentration as these organisms are consumed higher up the food chain.