Fish Oil Lawsuit Raises Safety Questions

A lawsuit charges that many fish oil supplements contain harmful PCBs, but don't throw out your pills just yet.

March 9, 2010

Oil from anchovies or other small fry, or from wild salmon, is less likely to be contaminated.

RODALE NEWS, EMMAUS, PA—Some of the largest fish oil supplement producers, and the stores that carry them, are selling supplements contaminated with a class of now-banned industrial chemicals known as polychlorinated biphenyl compounds, or PCBs, charges a lawsuit filed earlier this month by the Manteel Justice Foundation and two other citizens. "Consumers who want the health benefits of fish oil shouldn't have to take the health risks of an extremely toxic man-made chemical," David Roe, one of the attorneys for the plaintiffs, said in a press release.


THE DETAILS: The lawsuit names eight makers and sellers of fish oil, shark oil, fish liver oil, and shark liver oil supplements that the plaintiffs say are contaminated above the "safe harbor" limits set for human PCB consumption under California's Proposition 65, a law that requires consumers be warned about such harmful exposures. So far, defendants named in the lawsuit include CVS Pharmacy Inc.; General Nutrition Corp. (GNC); Now Health Groups, Inc.; Omega Protein, Inc.; Pharmavite LLC (Nature Made brand); Rite Aid Corp.; Solgar, Inc.; and TwinLab Corp. However, the plaintiffs say further testing will likely result in more manufacturers and marketers being added to the lawsuit.

PCBs, chemicals used extensively in the electricity industry decades ago, were banned in the late 1970s but still persist in our environment today. They were listed as known carcinogens and reproductive toxins in California 20 years ago. Although there are more than 200 different types of chemicals that fall under the PCB umbrella, only 12 of them are considered a serious hazard to human health. These are known as dioxinlike PCBs.

WHAT IT MEANS: When people take fish oil supplements, they're looking for health benefits associated with the oil's omega-3 fatty acids, not a mouthful of harmful toxins. However, some supplement-safety experts suggest the lawsuit is misleading to consumers. "Prop 65 in California is all about minimizing exposure," explains Tod Cooperman, MD, president of, an independent company that evaluates health-and-nutrition products. "It's not really about the safety of the product, but it's an admirable push to get contaminants out of products as much as possible."

The reality is, there's some level of PCB contamination in all fish. And while (unfortunately) there's no limit to PCB levels in fish oil sold in the United States, there are very strict limits in place in Europe. Dr. Cooperman explains that in Europe and generally in scientific research, scientists base limits on the 12 dioxinlike PCBs that have been shown to harm human health. However, Prop 65 doesn't distinguish between the more dangerous and less-benign PCBs. "In the law suit, the amount of these dioxin-like PCBs in a daily serving was less than one picogram [one trillionth of a gram] for seven products, and three had between 2 and 12 picograms," he explains. "To put these levels in context, experts convened by the World Health Organization concluded that an adult can ingest 160 picograms per day of the dioxin-like PCBs and dioxins (which are more toxic) over a lifetime without detectable health effects. [NOTE: erroneously reported that as 1600 picograms; 160 is the correct amount.] So we're talking about minuscule amounts of PCBs in these products, but it is best to avoid those with the highest levels.

"Nevertheless," he adds, "the case raises some legitimate issues as far as minimizing the amount of PCBs in fish oil."

Read on to find out how to spot the best fish oil supplements.

Dr. Cooperman also pointed out that the lawsuit focused on sources of fish oil most likely to be contaminated—oil pressed from the livers, and oil taken from larger fish. (As a rule of thumb, the larger the predatory fish, the greater the contamination.) However, these aren't the supplements consumers usually pick.

Here's how to choose the best fish oil supplement:

• Find oil from fish lower on the food chain. Stay away from cod liver or shark oils. Toxins accumulate in these large, predatory fish. Instead, opt for fish oil supplements made from smaller fish rich in omega-3s, such as anchovies, mackerel, or sardines. "These fish are going to have much lower levels [of contaminants]. There will still be a little bit," Dr. Cooperman adds. "It's unavoidable. It's in the water. But these are not dangerous levels at all."

You can keep salmon on your fish list too. Even though a salmon oil supplement was named in the lawsuit (NOW Foods Salmon Oil) because of its overall PCB levels, testing found it was extremely low in the harmful dioxinlike PCBs. Salmon oil is considered safe as long as its source is wild-caught Alaskan salmon, not its farmed counterpart. Fish taken from open bodies of water tend to have lower contamination levels than ones taken from more polluted inland bodies of water.

• Take note of the origin. Fish oils taken from the fish liver are going to be higher in PCBs because the liver is the organ that deals with contaminants. You want a fish oil pressed from the whole fish or fish flesh to get lower levels of PCBs and heavy metals.

For more information, offers a subscription report on fish oil and plans to release an updated report this summer.