Contaminants commonly detected in fish oil omega-3 supplements, and their negative health effects, include:

Total PCBs (Polychlorinated Biphenyls)

PCBs have been demonstrated to cause a variety of adverse health effects. Human studies have shown potential carcinogenic and non-carcinogenic effects of PCBs. The different health effects of PCBs may be interrelated. Alterations in one system may have significant implications for the other systems of the body.

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Dioxins and Furans

Studies show that dioxins and furans have the potential to produce a range of toxic effects in humans include:

  1. Skin disorders, such as chloracne
  2. Liver problems
  3. Impairment of the immune system, the endocrine system, and reproductive functions
  4. Effects on the developing nervous system and other developmental events
  5. Certain types of cancers

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Dioxin-Like PCBs

Human exposure to dioxins and dioxin-like substances has been associated with a range of toxic effects, including immunotoxicity, developmental and neurodevelopmental effects, and changes in thyroid and steroid hormones and reproductive function. Developmental effects are the most sensitive toxic endpoint making children, particularly breast-fed infants, the population most at risk.

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Chronic exposure to methylmercury may cause numbness and tingling in the extremities, blurred vision, deafness, lack of muscle coordination and intellectual impairment, as well as adverse effects on the cardiovascular, gastrointestinal, and reproductive systems. Prenatal exposure may interfere with fetal development of the central nervous system and cause neurological and developmental delays.

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Exposure to high lead levels can severely damage the brain and kidneys. Chronic exposure can result in decreased neurological performance. In pregnant women, exposure to high lead levels may cause miscarriage, and chronic exposure may affect the development of the fetus.

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Inorganic Arsenic

Inorganic arsenic is a confirmed carcinogen and is the most significant chemical contaminant in drinking water globally. Arsenic can also occur in an organic form. Inorganic arsenic compounds (such as those found in water) are highly toxic while organic arsenic compounds (such as those found in seafood) are less harmful to health.

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Chronic exposure to cadmium may cause kidney damage, bone mineral density loss and hypertension. Acute and chronic inhalation of cadmium can cause potentially fatal pulmonary dysfunction. In addition, cadmium has been classified as carcinogenic by the International Agency for Research on Cancer, with exposure being primarily associated with lung cancer.

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Why are these chemicals found in fish oil in the first place? They enter the environment from industrial activity and persist for a long time, bioaccumulating in large fatty fish. This means that oil derived from these fish could contain too-high concentrations of contaminants.
There’s no way to tell if your supplement is contaminated just by looking at it, or even by reading the label (companies typically only have to show testing documentation to sell legally, and there’s no guarantee of accuracy or legitimacy). Only laboratory testing can tell you for certain.

IFOS takes the guesswork out of it by making it easy to find pure, safe omega-3 supplements. Just look for the IFOS certification mark on product labels which means the product has been tested and verified that it doesn’t contain excess levels of contaminants.

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