The European Food Safety Authority (EFSA) has updated its safety threshold for dioxin exposure for the European population.
It said in a release that "dietary exposure to dioxins and dioxin-like polychlorinated biphenyls (PCBs) continues to raise a health concern."
The decision follows the World Health Organization's (WHO) update to its Toxic Equivalency Factor (TEF) calculations in 2022, which are used to assess the combined toxicity of dioxins and dioxin-like PCBs.
EFSA has lowered the Tolerable Weekly Intake (TWI) — the amount of dioxins a person can consume without an appreciable health risk — to 0.6 picograms per kilogram of body weight per week.
This new threshold is three times lower than the TWI established in 2018 using the previous WHO TEFs from 2005.
EFSA said the new health-based guidance value was based on developmental effects on male reproduction and is supported by evidence from both animal studies and human data.
Evidence has suggested that exposure before birth may affect sperm quality, sperm count and reproductive development later in life. The concern is particularly focused on pregnant women and women who may become pregnant.
What are dioxins and dioxin-like PCBs?
Dioxins and dioxin-like PCBs are toxic environmental pollutants that persist for decades. As they break down very slowly, they accumulate in soil, water and animal fat.
Thus, consumers are exposed through foods such as fish, meat, dairy products and eggs rather than through direct environmental contact.
Dioxins are unwanted byproducts from industrial processes, waste incineration and some combustion activities.
PCBs were industrial chemicals used in electrical equipment and other applications before being banned in many countries.
TEFs are internationally agreed values used to express the relative toxicity of dioxins and dioxin-like PCBs compared with the most toxic dioxin, i.e. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).
EFSA added that it had found that dietary exposure among the European population exceeds the new TWI across all age groups, with the highest exceedances in toddlers and children.
What happens next?
Maximum levels for dioxins and dioxin-like PCBs in food and feed are already set in European legislation.
The European Commission and Member States, in their role as risk managers, will consider EFSA's scientific advice when developing dietary guidance and reviewing the existing maximum levels, also taking into account the revised toxic equivalency factors (TEFs) to ensure a high level of consumer protection.
Possible outcomes include tighter limits on dioxins in food and animal feed, more monitoring of contamination, updates to dietary advice and more research into human exposure.
For nutraceutical and functional food formulators, this could impact contaminant limits and increase testing and monitoring requirements.