PFAS in soil
A systematic survey of locally elevated PFAS contamination in German soil has not yet been carried out. However, for several years now, the federal states, Bundeswehr and the Federal Agency for Real Estate (BImA) have been commissioning investigations into suspected cases and instances of contamination. In contrast, current investigation programmes run by the Federal Environment Agency focus on the diffuse, ubiquitous background contamination of soil by PFAS, which results in particular from atmospheric deposition (i.e. via air and rain). A respective recent report is available for download here.
PFAS that reach the soil are carried by seepage water into deeper layers and thus also enter groundwater. Long-chain PFAS are absorbed by soil and as a result it can take years or even decades before they seep into groundwater. In contrast, short-chain PFAS are more mobile and hardly bind to soil components. They are transported to deeper soil layers more rapidly and reach groundwater sooner. If PFAS-contaminated groundwater is used for irrigation of agricultural land, PFAS can be taken up by plants and enter the food chain.
To assess the risk to groundwater in suspected or known cases of PFAS contamination, Annex 2, Table 3 of the Federal Soil Protection and Contaminated Sites Ordinance (BBodSchV) prescribes threshold values for seven PFAS. If these values are exceeded, a detailed risk assessment must be carried out, taking into account the site-specific conditions, which in turn may lead to protective and remediation measures. For the other two exposure pathways to be considered under the BBodSchV, there are as yet no legally binding test values; however, proposed test values, supported by scientific evidence, were published in 2026 for the soil-to-human and soil-to-crop pathways.
Sites suspected of containing PFAS are often locations where fire-fighting foams have been used. These include fire-fighting training grounds, fire ponds, military airfields, airports and areas where large-scale fires have been extinguished.
The soil at (former) industrial sites with chromium electroplating baths may also be contaminated with PFAS. Furthermore, it is known that landfills, textile processing and paper manufacturing sites, as well as the photographic and film industries have caused PFAS contamination in soil and groundwater. Large-scale soil contamination via the air can be caused by fluorochemical companies, e.g. manufacturers and processors of fluoropolymers.
PFAS can enter agricultural land, for example, through the use of PFAS-contaminated sewage sludge, compost or other soil improvement products. It is also known that the ultra-short-chain PFAS compound trifluoroacetate (TFA), as a degradation product of fluorinated plant protection products, causes large-scaled groundwater contamination.
Case studies (hotspots) in Germany:
In southern Germany (Rastatt) and in the Hochsauerland district (Arnsberg, Möhne Dam), widespread PFAS contamination occurred as a result of mixing waste with compost and so-called soil improvers, which in some cases was in breach of the law.
Examples of PFAS entering soil and groundwater via fire-fighting foams include Nuremberg and Düsseldorf airports, and the Bundeswehr base at Manching Airport. These are only some of many airports where PFAS-containing fire-fighting foams were used for training purposes.
An example of soil contamination caused by atmospheric deposition can be found in Bavaria: Fluoropolymers are manufactured at the Gendorf Industrial Park. For decades, the emulsifier PFOA was released into the environment via exhaust air and wastewater. This led to significant contamination of soil and groundwater. Later, another PFAS compound was used instead of PFOA, which is also increasingly being detected in soil and groundwater.