So I had to investigate after I read about the recent lawsuit filed by consumer health activists charging that eight makers and sellers of fish-oil supplements violated California law by failing to warn consumers about their exposure to polychlorinated biphenyls (PCBs) in their products. After all, under California’s Proposition 65, the public has a right to be "informed about exposure to chemicals that cause cancer, birth defects, and reproductive harm."California’s Proposition 65 not only provides consumers with safety information, but it also has the effect of pressuring companies to drive risky chemicals out of their products, or at least to within "safe harbor" levels established by the state.
California has officially determined the safe-harbor level of exposure for the cancer risk posed by PCBs, but has not yet made a comparable determination for birth-defect risks posed by PCBs, said David Roe, an attorney for the plaintiffs and principal draftsman of the Prop 65 law. He explained that under Prop 65, safe-harbor levels set for cancer risks aren’t meant to be protective against birth-defect risks, even when the risks come from the same chemical.
I reviewed samples of some of the companies’ fish-oil labels; some gave the impression that the products contained no PCBs. For example, Twinlab’s Norwegian Cod Liver Oil and Emulsified Norwegian Cod Liver Oil both claim to be "PCB/Heavy metal free." But does "free" mean the products contained extremely low levels of PCBs or no detectable PCBs at all? When I asked a company spokesman about the products’ PCB levels, the company declined to comment on advice of counsel due to the lawsuit.The label for Now Foods’ Salmon Oil claims that it has been "screened for the absence of potentially harmful levels of contaminants," including PCBs. But a spokeswoman didn’t answer my specific questions about what the PCB levels actually were.
Pharmavite did provide details about PCB levels in its products. James Brooks, Ph.D., vice president for science and technology, e-mailed me that Nature Made Odorless Fish Oil contains PCBs in an amount less than 0.09 parts per million, per gram. When I asked whether that counts all 209 PCB "congeners," he responded that it counts "seven specific PCB congeners" in accordance with a voluntary monograph issued by an industry association, and that the product label had recently been revised to say so. "We firmly believe our fish-oil products are safe, comply with Prop 65, and do not require the warning," Brooks said.Bottom line: If you choose to take a fish-oil supplement, our experts say to look for products labeled "USP Verified," which means the product has been tested by the U.S. Pharmacopeia, a non-governmental standards-setting authority, for purity and potency. While USP verification is a quality standard, its program does help ensure that supplements contain the ingredients stated on the label, in the amounts listed, and that they meet what USP considers "acceptable limits" for contaminants, including PCBs.
—Doug Podolsky, senior editorSubscribers, use our Natural Medicine Ratings to find out which fish oil supplements are USP-verified.