Do Fish Oil Supplements Contain Organic Pollutants?

Fish oil supplements are currently experiencing a wave of increasing popularity among consumers.  Fish oil supplements contain essential polyunsaturated fatty acids (PUFAs) including both Omega 3 Fatty Acids as well as Omega 6 Fatty Acids.  Omega 3 fatty acids are essential fatty acids that mammals are unable to produce while omega 6 fatty acids are found in fish as well as other sources.

 

  1. Are you or a loved one currently taking a fish oil product?
  2. Do you know that some fish oil supplements may actually do more harm than good?

Important! If you’ve answered ‘yes’ to one or both of these questions, continue reading to find out what you need to know BEFORE you start taking a fish oil supplement.

Why are so many people starting to supplement their diets with fish oil?

Recent studies suggest that omega 3 fatty acids may confer potential health benefits including improving vascular health, reducing cardiovascular disease risk, reduce symptoms of rheumatoid arthritis, as well as reducing incidence of diabetes.

  • Improve vascular health
  • Reduce cardiovascular disease risk
  • Reduce symptoms of rheumatoid arthritis
  • Reduce incidence of diabetes

Are there reasons to be concerned about contaminants?

However, despite these health benefits, consumers have to ensure that the fish oil that they consume does not contain contaminants including mercury.  The results of a recent Canadian study also suggests that there are concerns that some fish oil supplements may contain polychorinated biphenyls (PCB’s) and organochlorine pesticides (Rawn et al, 2009).  Both polychorinated biphenyls and organochlorine pesticides are lipophilic which means that they have an affinity towards lipids or fats and are able to dissolve in them–this is one reason for the concern for these compounds being found in fish oil supplements.

Polychlorinated biphenyls (PCBs) are a class of organic compounds that were used in pesticides, flame retardants, paints, pesticides and more–then banned in the 70’s due to adverse health effects associated with their use.   To date, there continue to be several areas that have persistent pollution with PCBs including the Great Lakes.  Though they are no longer produced in the United States, PCBs are still found in the environment.  Adverse health effects linked to PCB exposure include skin conditions such as chloracne, lowered immune response, and possible cancers of the liver and biliary tract in humans among other concerns.

Is there cause for concern?

In this Canadian study which involved a sample of commercially available fish oil products that are marketed in Canada–all of the samples analyzed were found to contain detectable residues of both organochlorine pesticides and PCBs. Highest levels of PCBs were found in shark oil samples while the lowest PCB levels were found in mixed fish oil samples (anchovy, mackerel, and sardine).  This particular study found that seal oil consumption would result in the higher organocholorine pesticide consumption than other types of fish oil.

Total PCB intakes ranged between 0.896 ng/d (0.285 ng/d marker PCBs) and 15700 ng/d (7620 ng/d marker PCBs), in a supplement containing anchovy, mackerel, and sardines and a shark oil supplement, respectively. The seal oil supplement resulted in the next highest intake estimate (1560 ng/d). In comparison, consumption of a single 150 g meal of farmed salmon with an average PCB concentration of 17.5 ng/g would result in exposure to 2630 ng PCBs.

What can you to minimize your exposure to these toxins?

There are two things that you can do as a consumer of both fish oil products as well as fish.  First, try to avoid eating farmed Salmon, for example, as studies suggested that they contain higher levels of these persistent organic pollutants.  Secondly, if you’re going to take a fish oil supplement, ensure that your supplement has been 3rd party tested–specifically to conform to the International Fish Oil Standards (IFOS).

  • Avoid consuming farmed salmon.
  • Ensure that any fish oil product that you buy is 3rd party tested specifically to adhere to International Fish Oil Standards (IFOS).

Reference:

  1. Rawn DF, Breakell K, Verigin V, Nicolidakis H, Sit D, Feeley M. Persistent organic pollutants in fish oil supplements on the canadian market: polychlorinated biphenyls and organochlorine insecticides. J Food Sci. 2009 Jan;74(1):T14-9.