I have read about dioxins being high in farm fed salmon - would this mean that salmon oil supplements or omega fat supplements would also be high in dioxin?

linda barton

Dioxins have never been produced intentionally. They may be formed as unwanted by-products in a variety of industrial processes and some domestic ones like household fires. They are found throughout the environment and fish accumulate them from what they eat, including other fish and fish feed.

The manufacture and general use of PCBs stopped in the 1970s and there are strict controls in place on the release of dioxins. In this context the World Health Organization set safety levels for dioxins in 2001 based exclusively on public health protection. As a result the levels in the environment, and thus in foodstuffs, are falling, and between 1997 and 2001 the average adult intake of these chemicals has halved.

Nowadays, the amounts of dioxins present in fish are below the safety levels set by the World Health Organization (WHO), the US Food and Drug Administration, the Canadian Food Inspection Agency and the European Union (EU). These limits are based on achieving minimum risk for someone consuming relatively large amounts of the food in question throughout their lifetime. Therefore, there is no reason to avoid eating farmed salmon or any other fish.

Fish is also an essential part of a healthy diet. Fish should be consumed at least two portions a week, because of the proven wide physical and mental health benefits of the omega-3 fatty acids they contain. The proven benefits of oily fish far outweigh the theoretical risks.

Concerning the fish oil supplements, the Food Safety Authority of Ireland (FSAI) and the Food Standards Agency (UK) have examined a range of the capsules for the presence of dioxins. There is an enormous variation in the level of dioxins found in fish oil capsules. The brands in which the levels exceed the safety limits have been recall from supermarkets. Another survey of fish products (1997) indicated that the fish liver oils contained a higher concentration of the dioxins and PCBs than the fish body oils.

However, it's better to eat fish than take fish oil-supplements, because as well as containing omega-3, fish is an excellent source of other nutrients.

Although the industrial sources of dioxins and PCBs are now strictly controlled, both groups of chemicals are very persistent and will remain in the environment for many more years. The concentrations of both dioxins and PCBs in the diet are expected to continue to fall as further measures to reduce emissions into the environment take effect.

See also:

http://europa.eu.int/comm/environment/dioxin/