Despite less PFAS in free-range and barn eggs, eggs and egg products still contribute to overall exposure

The German Federal Ministry for the Environment, Climate Action, Nature Conservation and Nuclear Safety (BMUKN) tasked the German Federal Institute for Risk Assessment (BfRshort forGerman Federal Institute for Risk Assessment) with conducting a health risk assessment of data on the occurrence of per- and polyfluoroalkyl substances (PFAS) in chicken eggs based on food monitoring data from 2024. The goal was to make the evaluation as differentiated as possible with respect to production types respectively farming methods.

The results of the evaluation can be summarised as follows:

2.1 Occurrence data from the 2024 monitoring

In the available data set on the occurrence of per- and polyfluoroalkyl substances (PFAS) in chicken eggs from the 2024 monitoring, the proportion of samples with concentrations above the limit of quantification (LOQshort forLimit of quantification) for the sum of the four PFAS (PFOS, PFOA, PFNA and PFHxS) is 24 % in total, with major differences between the types of farming. The mean concentration of the sum of the four PFAS in eggs from organic production is 0.09 μg/kgshort forkilogram (lower bound (LB) approach) and 0.07 μg/kgshort forkilogram (LB) for free-range eggs, while the average concentration of the sum of the four PFAS in barn eggs is many times lower (0.001 μg/kgshort forkilogram, LB).

None of the samples with quantifiable PFAS concentrations exceeded the maximum level of 1.7 µgshort formicrogram/kgshort forkilogram for the sum of the four PFAS compounds specified in Regulation (EU) 2023/915. The corresponding maximum levels for the four individual compounds were also not exceeded.

2.1.1 Exposure assessment

Based on the occurrence data from the monitoring (2024), the BfRshort forGerman Federal Institute for Risk Assessment has conducted an exposure assessment for the four PFAS (PFOS, PFOA, PFNA and PFHxS) named in Regulation (EU) 2023/915 through the consumption of chicken eggs from different farming systems (barn, free-range and organic production) for children and adults. Three hypothetical consumption scenarios for eggs were used, with the assumption that only chicken eggs from one of three farming systems are consumed (only barn, free-range or organic production). For the risk characterisation, the tolerable weekly intake (TWI) of 4.4 nanograms (ng) per kilogram (kgshort forkilogram) of body weight (bw) per week for the sum of the four PFAS mentioned above, as derived by the European Food Safety Authority (EFSAshort forEuropean Food Safety Authority), was used as a basis (EFSAshort forEuropean Food Safety Authority 2020).

a. For adults in Germany, long-term exposure to the sum of the four EFSAshort forEuropean Food Safety Authority PFAS through the consumption of chicken eggs with average concentrations, using the LB, ranges from 0.002 to 0.17 ng/kgshort forkilogram bw per week (50th percentile) to 0.005 to 0.54 ng/kgshort forkilogram bw per week (95th percentile), depending on the consumption scenario considered. This means that the estimated exposure to the four PFAS is below the TWI of 4.4 ng/kgshort forkilogram bw per week and reaches 0.05–4% (50th percentile) or 0.1–11 % (95th percentile) of the TWI. When comparing the three scenarios, long-term PFAS exposure from the consumption of free-range and organic eggs is highest (8–11 % of the TWI in the 95th percentile).

b. In children, long-term exposure to PFAS through the consumption of chicken eggs exceeds that of adults by about three to five times in all scenarios. Depending on the consumption scenario considered, the long-term exposure of children in Germany to the sum of the four PFAS through the consumption of chicken eggs ranges from 0.01–0.57 ng/kgshort forkilogram BW per week (50th percentile) to 0.02–2.00 ng/kgshort forkilogram bw per week (95th percentile). The exposure corresponds to 0.2–13 % (50th percentile) and 0.5–45 % (95th percentile) of the TWI, respectively. As with adults, when comparing the three scenarios, the long-term PFAS exposure of children is highest when consuming free-range and organic eggs (33–45 % of the TWI in the 95th percentile).

2.2 Conclusion

Due to the ubiquitous prevalence of PFAS in the environment and their prevalence in numerous consumer products and foods, overall exposure is composed of many different sources.

The exposure assessment based on three hypothetical scenarios shows that the consumption of chicken eggs – especially free-range and organic eggs – can make a substantial contribution to overall exposure to PFAS. However, if eggs are sourced exclusively from one farming system, these results can be interpreted as realistic lower and upper estimates of actual exposure.

Compared to current concentrations, though, the average PFAS concentrations in eggs from all production types have declined over the years. The average PFAS concentrations in chicken eggs in the 2007–2020 data set are 0.36 µgshort formicrogram/kgshort forkilogram (95th percentile: 1.6 µgshort formicrogram/kgshort forkilogram), in the years 2018–2022 at 0.29 µgshort formicrogram/kgshort forkilogram (95th percentile: 1.00 µgshort formicrogram/kgshort forkilogram) and in the 2024 monitoring at 0.06 µgshort formicrogram/kgshort forkilogram (95th percentile: 0.42 µgshort formicrogram/kgshort forkilogram). This corresponds to a four- to six-fold decrease in PFAS concentrations in chicken eggs. The decline in PFAS concentrations is most pronounced in recent years (2018–2022 compared to 2024). As PFAS concentrations in chicken eggs, especially in eggs from barn and free-range farming, are lower than in 2018–2022, exposure for adults and children is currently lower. While the exposure assessment for children based on the 2018–2022 occurrence data exceeds the TWI (scenario 2: free-range; 95th percentile, LB), exposure based on monitoring data from 2024 (LB) reaches a maximum of 45 % of the TWI (scenario 3, 95th percentile).