Dioxins: Updated risk assessment by the European Food Safety Authority (EFSAshort forEuropean Food Safety Authority) New calculation significantly reduces the tolerable weekly intake
What it's about:
EFSAshort forEuropean Food Safety Authority has updated External Link:its opinion on dioxins and dioxin-like polychlorinated biphenyls (dl-PCBs). Among other things, the opinion lowered the tolerable weekly intake (TWI) for dioxins and dl-PCBs from 2 picograms (2 x10⁻¹²grams) to 0.6 picograms per kilogram of body weight. The TWI value refers to the amount of a substance at which no adverse health effects are expected in humans following lifelong weekly intake.
This new TWI value is more than three times lower than the value previously advocated by EFSAshort forEuropean Food Safety Authority in 2018. This change is primarily based on methodological updates in the derivation of the TWI; no new toxicological data is available that would have necessitated this reduction.
According to EFSAshort forEuropean Food Safety Authority, the average intake of dioxins and dl-PCBs for people of all age groups exceeds this new TWI value. EFSAshort forEuropean Food Safety Authority sees risks of adverse health effects particularly for infants and children. According to EFSAshort forEuropean Food Safety Authority, exposureExposureTo glossary of women of childbearing age may also pose health risks to the unborn child in the womb. For other adults, EFSAshort forEuropean Food Safety Authority sees no evidence that their current exposure is associated with health risks.
At the same time, EFSAshort forEuropean Food Safety Authority emphasises the high levels of uncertainty associated with the derivation of the TWI, the exposure estimates and, ultimately, the risk assessment, which have led to a rather conservative assessment. To address some of the uncertainties regarding exposure, EFSAshort forEuropean Food Safety Authority recommends that the analytical and calculation methods as well as the amount of available data should be further improved, for example by collecting further data on the levels of dioxins in plant-based foods, as well as in breast milk and blood samples.
In general, human exposure to dioxins and dioxin-like PCBs in Germany has declined considerably over the last 30 years.
Given the known teratogenic effects of dioxins, particularly on male offspring, the TWI has been derived for women of childbearing age. Provided the established TWI value is adhered to, no health risks are expected for male offspring. The TWI is based on a study in rats in which a reduced sperm concentration was observed in the offspring with increasing doses of tetrachlorodibenzodioxin (TCDD) (Faqi et al.short foret alii (lat. "and others"), 1998). This TWI is used for all population groups. Therefore, in this opinion, EFSAshort forEuropean Food Safety Authority also discusses the significance of exceeding the TWI for the different population groups in a qualitative assessment.
Dioxins are produced under certain conditions during combustion processes; PCBs were manufactured for various applications, such as insulating oils and hydraulic fluids, as well as plasticisers. PCBs have not been produced since the 1980s. Due to their persistence, they are still present in the environment. Both the dioxin group and the PCB group comprise substances potentially harmful to health and possessing long biological half-lives.
Due to their presence in the environment, their entry into the food chain is unavoidable. The substances accumulate in the fat of animals and are ingested by humans mainly through the consumption of animal-based foods such as meat, fish, eggs, milk and dairy products. When comparing existing human biomonitoring data, particularly dioxin levels in breast milk, with external exposure estimates, it is striking that the external exposure estimate suggests significantly higher values than those actually measured. EFSAshort forEuropean Food Safety Authority interprets this as an indication that the external exposure estimate overestimates actual exposure. If the risk characterisation is based on internal exposure, using existing human biomonitoring data, the overall picture is significantly less problematic, as EFSAshort forEuropean Food Safety Authority also notes. Nevertheless, according to EFSAshort forEuropean Food Safety Authority, the fundamental conclusion remains that the exposure of infants, children and women of childbearing age is too high.
EFSAshort forEuropean Food Safety Authority had put the draft of its updated dioxin opinion out for public consultation on 27 November 2025. The consultation period ended on 26 January 2026. The German Federal Institute for Risk Assessment (BfRshort forGerman Federal Institute for Risk Assessment) also reviewed and commented on the draft.
EFSAshort forEuropean Food Safety Authority also announced that, on behalf of the European Commission, it would carry out a risk-benefit assessment of fish consumption by the end of 2027. The aim is to assess the health benefits of eating fish concomitant with the health risks posed by the intake of undesirable substances, including dioxins.