Dioxins and polychlorinated biphenyls (PCBs)
As of 1 January 2012 and December 2013, respectively, new legally binding maximum levels (limit values) and voluntary action levels (early warning system) apply across Europa to harmful dioxins and polychlorinated biphenyls (PCBs) in various types of food of animal origin, vegetable oils and infant food. In particular, harmonising previously differing national maximum levels for non-dioxin-like PCBs in food, which resulted in tightened provisions as compared to former German limit values, and expanding the provisions to also apply to foods for infants and young children for reasons of precaution are a tangible contribution to improving the protection of consumer health and food safety.
Europe-wide action levels and maximum levels for dioxins and dioxin-like PCBs (dl-PCBs) in selected types of food:
|Europe-wide action||EU action level pg WHO-TEQ/g fat||EU maximum level pg WHO-TEQ/g fat|
|Dioxins||dl-PCBs||Dioxins||Dioxins + dl-PCB|
|Meat and meat products||1,25||0,75||1,75||3,0|
|Oils and fats||-||-||1,75||3,0|
|Hen eggs and egg products||1,75||1,75||2,5||5,0|
|Bovine animals and sheep|
|Meat and meat products||1,75||1,75||2,5||4,0|
|Oils and fats||-||-||2,5||4,0|
|Milk and dairy products including butter fat||1,75||2||2,5||5,5|
|Meat and meat products||0,75||0,5||1,0||1,25|
|Oils and fats||-||-||1,0||1,25|
|Mixed animal fats||1,0||0,75||1,5||2,5|
- Unit of measurement: 1 pg (picogram) = 0.000 000 000 001 gram
- Action levels: Commission Recommendation of 11 September 2014 amending the Annex to Recommendation 2013/711/EU on the reduction of the presence of dioxins, furans and PCBs in feed and food (2014/663/EU; Official Journal of the European Union Number L 272, p. 17-18)
- Maximum levels: Comission Regulation (EU) Number 1259/2011 of 2 December 2011 amending Regulation (EC) Number 1881/2006 as regards maximum levels for dioxins, dioxin-like PCBs and non-dioxin-like PCBs in foodstuffs (OJ L 320, 03/12/2011, p. 18–23)
As of 1 January 2012 the provisions on maximum levels for dioxins and the sum of dioxins and dioxin-like PCBs have been supplemented by an EU-wide maximum level of 40 nanograms per gram of fat (1 nanogram = 0.000 000 001 gram) for the also harmful non-dioxin-like PCBs in food such as meat of poultry, bovine animals, sheep and pigs, as well as milk, eggs and mixed animal fats.
As of 1 January 2014 new maximum levels apply EU-wide for dioxins and PCBs in livers of terrestrial animals and derived products thereof. The Federal Institute for Risk Assessment (Bundesinstitut für Risikobewertung – BfR) recommends continued avoidance of the consumption of sheep liver.
New EU-wide maximum levels for dioxins and PCBs in livers of terrestrial animals as of 1 January 2014
|Foodstuffs||EU maximum pg WHO-TEQ/g wet weight||EU maximum level ng/g wet weight|
|Dioxins||Dioxins + dl-PCB||ndl-PCB|
|Liver and derived products thereof from poultry, bovine animals and pigs||0,3||0,5||3,0|
|Liver and derived products thereof from sheep||1,25||2,0||3,0|
- Unit of measurement: 1 ng (nanogram) = 0.000 000 001 gram
- Unit of measurement: 1 pg (picogram) = 0.000 000 000 001 gram
- Maximum levels: Commission Regulation (EU) Number 1067/2013 of 30 October 2013 amending Regulation (EC) Number 1881/2006 as regards maximum levels of the contaminants dioxins, dioxin-like PCBs and non-dioxin-like PCBs in liver of terrestrial animals
Dioxins and PCBs in the environment
Harmful Dioxins and polychlorinated biphenyls (PCBs) can enter foodstuffs through air, soil or sediments. These substances, which contaminate food, are therefore also referred to as environmental contaminants. Dioxins have never been specifically produced, they are unintended or undesired by-products of chemical processes in the chlorine-based chemical industry and any combustion process involving chlorine or organic carbon under specific circumstances (such as temperatures between 250 degrees and 800 degrees and specific residence times). Unlike dioxins, PCBs used to be produced for specific purposes, mainly as non-burning, non-conductive viscous liquids for use in transformers and hydraulics (mining).
Since the mid-1980s, the release of dioxins and PCBs into the environment has been reduced thanks to numerous regulatory measures. Dioxin emissions from known sources dropped by more than 90 percent between 1990 and 2004. By 2010 values had dropped even further. Today thermal processes of metal production and processing and small combustion systems cause major part of dioxin emissions.
How dioxins and PCBs enter the food chain
Nevertheless, due to their persistence dioxins and PCBs still exist as a kind of pollution legacy all over the environment, although most present levels are quite low. In particular soil and sediments in water bodies are both reservoirs of pollutants and, due to remobilization, major sources for the transfer of these pollutants into the food chain. In addition, negligent disposal of waste products and equipment containing PCBs prevent a further reduction in their presence in the environment and thus in the food chain. Due to the persistence of the substances, the significant drop in dioxin and PCB inputs into the environment in the last 20 years has as yet not been reflected in a similar reduction of pollutant loads in all foodstuff groups from all types of farming.
Accumulation of dioxins and PCBs in the food chain
Milk is the most thoroughly analysed type of food. Between 1987 and 2000 the dioxin content of milk dropped by around 80 percent from approximately 2.3 to around 0.4 picogram dioxin toxic equivalent per gram of milk fat (1 picogram = 0.000 000 000 001 gram). Since then, the content has remained at a low level with minor fluctuations. Thus the average dioxin content in milk is also well below the EU-wide action level or maximum level, which entered into force on 1 January 2012.
Decrease in dioxin levels in milk from 1987 to 2017
However, nationwide findings of the Länder document that dioxin and dioxin-like PCB concentrations exceeding EU maximum levels are regularly found in rare foods such as the liver of lambs, sheep, deer or Baltic cod and in the muscle meat of freshwater fish. As a result, these products may not be marketed. In addition to the legal provisions, the Federal Environment Ministry has also drawn up tips for the health protection of consumers.
The diagram illustrates that 70 percent of dioxin and PCB intake from foodstuffs comes from consuming the animal products eggs, milk and dairy products, poultry, beef and pork.
Early warning system
Alongside binding EU maximum levels for dioxins and PCBs in various types of food, non-binding action levels were stipulated for the first time in 2002 to limit the presence of dioxins and PCBs in food. Dioxins and dioxin-like PCBs are emitted from different sources. Therefore, separate action levels for each group of substances were laid down. Depending on the type of food, action levels are between 25 and 30 percent lower than the respective maximum levels. Action levels serve as an early warning system to help recognise above average concentrations, for example levels exceeding the so-called background contamination which cannot be avoided by producers. Applying action levels helps to reduce dioxins and PCBs in food. They serve to identify, control or eliminate sources of contamination before maximum levels are exceeded. Commission Recommendation 2013/711 of 3 December 2013 on the reduction of the presence of dioxins, furans and PCBs in feed and food includes the different action levels for dioxins and dioxin-like PCBs which entered into force on 1 January 2012.