Skip to main content

Researchers criticize exposure limits for PFAS

Danish researchers have shown that the EU’s limits for PFAS are erroneous. This may well have serious consequences for estimating the costs for the anticipated clean-up.

Det new and intense focus on PFAS in recent years has attracted much attention from public authorities and citizens in regard to the serious and lasting PFAS contamination. With time, tolerable limits for PFAS have been lowered.

But they are still too high, according to a scientific article just published in the journal Environmental Health.

In this publication, Professor of Biostatistics at the University of Copenhagen, Esben Budtz-Jørgensen, and Professor of Environmental Medicine at University of Southern Denmark, Philippe Grandjean, review the calculations that form the basis for EU’s most recent exposure limits for PFAS.

Limit ten times too high

The most recent government budget includes funds to evaluate the extent of the environmental contamination. The plans rely on the EU limit for PFAS exposure from 2020.

But now the researchers question the EU limit, which has been developed by the European Food Safety Authority (EFSA).

- We can see from the calculations that EFSA has not complied with their own rules, and we find that EFSA has made erroneous calculations. That means that, for the two most important PFASs (PFOS and PFOA), the limit is about ten time too high, says Philippe Grandjean.

More toxic than anticipated

He collaborated with Professor of Biostatistics Esben Budtz-Jørgensen to review the calculations of health risks associated with different levels of PFAS exposure – and then the estimated dose that does not materially affect human health. This is how the exposure limit is defined.
Meet the researcher

Philippe Grandjean is Professor of Environmental Medicine at the Department of Public Health. His many years of research have made him a well-known figure in the public eye on topics such as mercury in fish, men's sperm quality, asbestos, pesticides, hormone disruption, and more recently, especially PFAS.


Meet the researcher

Esben Budtz-Jørgensen is professor at Section of Biostatistics at the University of Copenhagen.


We have repeatedly seen that PFAS was mote toxic than we feared

Philippe Grandjean, professor

-That’s why it’s particularly unfortunate that the EU experts have so clearly miscalculated. This will undoubtedly cause legal problems and likely delay the clean-up.

If the exposure limit is lowered as indicated by the researchers, it will result is greater amounts of contamination that will need to be removed. And additional costs.

Hoping for attention from the EU

Philippe Grandjean and Esben Budtz-Jørgensen have previously contributed to calculating exposure limits. But not this time, where they were invited to send comments only.

-When we realized that the errors were of a rather general nature, we decided that we needed to review the full procedure in a scientific article. That took some time to compile the details, but we now hope that the EU will listen and tighten the PFAS exposure limit, says Esben Budtz-Jørgensen.

The researchers’ calculations are now published on

Facts about the PFAS limit:

The PFAS limit has been developed by EFSA and can therefore be applied in the EU throughout. The limit represents the highest tolerable weekly intake of the four most common PFASs per kilogram of body weight. The limit can then be translated into specific values for drinking water, food, soil, etc. The limit of 4.4 nanograms has been translated to a limit of 2 nanograms per liter of drinking water. Budz-Jørgensen and Grandjean believe that the health-based limit should rather be 0.2 – one-tenth of the official value.


Editing was completed: 15.05.2023