Some Fish Oil Supplements Fishy on Quality

Dec. 7, 2011 -- Some popular fish oil supplements may be a little fishy when it comes to quality.

A new test of 15 top-selling fish oil supplements by Consumer Reports shows five fell a bit short on quality.

The good news is all 15 of the fish oil supplements evaluated by an independent lab contained their labeled amount of EPA and DHA, omega-3 fatty acids that have been shown to reduce the risk of heart attacks and stroke.

But four of the fish oil supplements tested contained trace levels of polychlorinated biphenyls (PCBs).

“In our recent tests, we found that some were not as pure as one might think,” Ronni Sandroff, editorial director of Health and Family at Consumer Reports, says in a news release.  

Another supplement’s coating failed to meet U.S. Pharmacopeia (USP, a non-government pharmaceutical standards-setting organization) standards for disintegration.

PCBs in Fish Oil Supplements

None of the fish oil supplements contained contaminants, such as lead, mercury, or PCBs, that exceeded levels set by USP or the European Union.

However, four of the fish oil supplements contained total PCBs in levels that would require warning labels under California’s Proposition 65, a consumer right-to-know law.

PCBs are part of a group of man-made organic chemicals that were widely used in industry until they were banned in 1979 after they were linked to cancer.

Although no longer in use, the chemicals accumulate in the environment and are sometimes found in fish and plants that have been exposed to contaminated water or soil.

Researchers say most of the tested fish oil supplements claimed to be “purified” or “free” of PCBs and other contaminants. But those claims have no specific regulatory definition, according to the FDA.

Dietary supplement companies base these claims on self-regulatory or European standards. For example, the USP limit on PCBs is 2 parts per trillion per gram.

The report does not say what levels of PCBs were found in the fish oil supplements. Researchers say the total PCB amounts in four brands (CVS Natural, GNC Triple Organic, Nature’s Bounty Odorless, and Sundown Naturals) were below the USP safe limit but within the range that would require a warning label under California’s Proposition 65, 90 parts per billion.