For the past two years, there has been a lot of news about a “new” contaminant, “PFAS,” which has caused a lot of inconvenience in the construction and soil industries. Recently it was demonstrated in America that there is a bacterium that breaks down this worrying group of substances. Geofoxx and Orvion are jointly conducting research into the extent to which plants can tackle soil contaminants. The DNA analyses used in this study led us to suspect that this bacterium is also present in the province of South Holland. Specific research was carried out with the support of the province of South Holland and the Omgevingsdienst Midden-Holland.
Poly- and perfluoroalkyl substances or PFAS have many useful applications and are used, for example, in non-stick pans, clothing and fire-fighting foams. Useful properties of these substances are namely water and heat resistance. Unfortunately, this also makes it very difficult for these substances to break down in nature. As a result of large-scale use, these substances can now be found in the soil, groundwater and even in people’s blood. In addition, these substances may cause cancer and infertility if exposed and accumulated for a long period of time. This has led to standards for the permissible concentration of PFAS in soil in the past two years. This led to much controversy and many construction projects were stalled due to the strict standards.
American researchers at Princeton University published a study in late 2019 on a bacterium called ‘Acidimicrobium A6’, which can break down PFAS and render them harmless. In response, environmental consultancy Geofoxx, in collaboration with the Orvion laboratory, conducted a study on the presence of this bacterium (family) in the province of South Holland. The ‘A6’ bacterium itself was not found, but related species were found in places with low acidity, iron- and ammonium-rich soil, and low oxygen concentrations (very wet soils). Laboratory tests have yet to confirm whether the naturally occurring bacterial population in the Netherlands does indeed break down PFAS.
The bacterial family could potentially start to make an important contribution to soil management in the Netherlands, by slowly but steadily degrading PFAS. The natural method would offer a good solution for (large) areas with low concentrations of PFAS. For example, to make areas available for housing or nature in the long term. The biological and physical conditions can be adapted, for example, by raising the groundwater levels and using plants whose roots play an important role in the degradation process.
Another technical possibility is for “hotspots” to grow hyperactive bacteria in reactors and add them to the soil, in places with high concentrations of PFAS (“bioaugmentation”). While this is still in its infancy for these species, it remains promising for the future.
Geofoxx and Orvion are in the starting blocks to gather additional knowledge to capitalize on these opportunities.
The project was carried out as part of the Soil Implementation Programme and commissioned by the Province of South Holland. There is also collaboration with the Omgevingsdienst Midden Holland and a student team from Wageningen UR. For more information please contact Luuk de Vetten (06-53354095), Paul Appeldoorn (06-15905344) and/or Jeroen Oosterwegel (06-20011987).