Dioxins and PCBs in Swedish food

Östersjön

Is it possible to eat fatty fish from the Baltic Sea and the lakes Vänern and Vättern? Children and women in their childbearing years (including pregnant and nursing women) should limit their consumption of contaminated fish, such as Baltic Sea herring. Below is information about the organic persistent pollutants called dioxins and PCBs and how they can affect us.

Dietary recommendations for groups at risk

Maximum limits (ML) for dioxins in food and feed are one tool for measures against the sale of foodstuffs contaminated with high levels of dioxins and PCBs. However, in Sweden we have a derogation from the ML, enabling the sale of fatty fish on the market regardless of levels of dioxins and PCB.  The derogation was given by the European Commission under the condition that the Swedish NFA provides and informs about risks and dietary advice to the groups at highest risks (children and women in fertile age). Following the dietary recommendations concerning contaminated fish will give these risk groups adequate protection from a high dioxin intake.

Decreased average dioxin intake

Emissions of dioxins from combustion processes and the chemical industry have been significant sources of contamination to Swedish foodstuff. Owing to decisive steps taken against emissions, today's population is exposed to considerably lower levels of dioxins than in the beginning of the 1970s.

The National Food Agency's investigations of dioxin intake from food suggest that the average intake has been more than halved over the past 15 years (Livsmedelsverket, 2012). The average dioxin level in breast milk, which is a measure of the dioxin concentration in a woman's body during pregnancy, is less than one tenth of the levels measured in the 1970s in the Stockholm-Uppsala area (Norén and Meironyté, 2000; Lignell et al., 2012).

Low consumption of Baltic Sea herring

The average consumption of herring from the Baltic is at present low in Sweden. A National Food Agency dietary study from 2010 ("Riksmaten 2010") showed that adults in Sweden consumed Baltic herring on average two times per year (Livsmedelsverket, 2013). The average consumption of wild-caught Baltic salmon was less than one portion per year.

In 2007 it was estimated that 6% of Swedish women in the age group 18-45 consumed herring at least 2 times per month (Livsmedelsverket, 2013). This is considered as a high consumption which increases the risk of women exceeding the tolerable intake of dioxins (Livsmedelsverket, 2013). The current recommended maximum consumption of Baltic Sea herring and salmon for young women in Sweden is 2-3 times per year.

A dietary study of children in 2003 showed that more than 60% did not consume Baltic Sea herring at all (Livsmedelsverket, 2013). This can be compared with the recommended intake for this group of 2-3 times per year. About 5% of the children consumed this type of fish once a month or more (Livsmedelsverket, 2013).

Tolerable intakes

In the EU, a tolerable weekly dioxin intake of two picogram (pg) WHO-TEQ/kg body weight has been set by the European food safety authority (Efsa, 2018). The tolerable intake represents the level considered safe over a lifetime and exceeding the tolerable intake limit for a brief period does not result in increased risk to health, as long as the average intake is below the tolerable intake over an extended time period.

The average intake of dioxins in the adult Swedish population as a whole is at present 3.5 pg/kg bodyweight/week (Livsmedelsverket, 2013). This can be compared to a reported average dioxin intake in Spain of 14 pg/kg bodyweight/week (2006), about 5 pg/kg body weight/week in the Netherlands (2004) and Belgium (2008), and 9 pg/kg/week in Finland (1998-2000) (Livsmedelsverket, 2013).

Overall, among Swedish adults the consumption of fish contributes on average to approximately 50% of the total dioxin intake (Livsmedelsverket, 2012). Consumption of Baltic Sea herring gives a contribution of about 12% (Livsmedelsverket, 2013). Other dietary sources to dioxins are meat, milk and dairy products, eggs and vegetable fat.

References

Efsa (2018) Risk for animal and human health related to the presence of dioxins and dioxin-like PCBs in feed and food. Scientific opinion

Lignell S, Aune M, Glynn A, Cantillana T, Fridén U. Levels of persistent halogenated organic pollutants (POP) in mother´s milk from first-time mothers in Uppsala, Sweden – results from 2008/2010 and temporal trends 1996-2010. Report to the Swedish EPA. http://www.slv.se/upload/dokument/risker/kemiska/Sakrapport_trend9610_121015.pdf

Livsmedelsverket (2013). Risk and benefit assessment of herring and salmonid fish from the Baltic Sea area. Report no 21-2013.

Livsmedelsverket (2012) Market Basket 2010 – chemical analysis, exposure estimation and health-related assessment of nutrients and toxic compounds in Swedish food baskets. Report no. 7 – 2012. 

Norén K and Meironyté D (2000) Certain organochlorine and organobromine contaminants in Swedish human milk in perspective of past 20-30 years. Chemosphere 40, 1111-1123.

Reviewed 2018-11-23