The PFAS present in plant protection products do not necessarily have the same effects as the substances of concern that generate so much controversy. Some frequently asked questions are answered below (June 2024).
- What are PFAS?
- Why are PFAS used?
- Why are PFAS in the news?
- Are PFAS used in plant protection products?
- How toxic is the breakdown agent TFA?
- Do PFAS in plant protection products pose a risk to public health or the environment?
- What is being done at European level to reduce the risks posed by PFAS?
- Is Belgium taking additional measures for plant protection products?
- Is the share of plant protection products in total PFAS use important?
- Where can I find more information on PFAS?
1.#What are PFAS?
PFAS stands for per- and polyfluoroalkyl substances. They are a diverse group of synthetic substances used for many different applications. Given the broad definition of PFAS, it is not obvious to make general statements about their properties.
It is therefore useful to highlight that there has been some confusion caused by the "broad" definition of this group of molecules. There is a legitimate but well studied concern about the pollution of our environment with perfluoroalkyl substances, with PFOA, PFNA, PFHxS and PFOS as examples.
An extended definition (from ECHA) also includes polyfluoroalkyl substances, which correspond to a number of active substances used as plant protection productsPolyfluoroalkyl substances, in terms of structure and therefore properties, are broadly quite different from perfluoroalkyl substances. Their potential effects on the environment and on human health are therefore not necessarily of the same order as of the examples of PFAS of proven concern cited above.
Active substances of plant protection products, however, are subject to extensive scrutiny before allowing any use, unlike most of the other PFAS.
A useful summary regarding the uses and classifications of PFAS can be found in this OECD document.
2.#Why are PFAS used?
PFAS are designed to be difficult to degrade, or heat-resistant or water-repellent, which can make them useful for manufacturing e.g. non-stick pans, fire extinguishers and rainwear. In plant protection products, they can provide long-lasting and improved efficacy. An overview of the main uses and quantities in Belgium is given in this report.)
3.#Why are PFAS in the news?
There are concerns about the potential harmful effects of PFAS on human health and the environment. Some PFAS are highly persistent, meaning they can remain in the environment for a long time. Some PFAS can also bioaccumulate, meaning they can accumulate in living organisms. There are so many different substances in this group that the toxicity of all of them is not yet sufficiently known. All this together makes it difficult to predict what the long-term effects will be, which is obviously an undesirable situation.
4.#Are PFAS used in plant protection products?
Yes, PFAS are used in a number of plant protection products. Plant protection products are compound mixtures, and both the active substance and the other ingredients can be PFAS.
In Belgium, there are 32 active substances in plant protection products that, according to the broad definition, are PFAS (see also a list of those active substances with their structure). As mentioned under question 1, these are polyfluoroalkyl substances, which are very different from perfluoroalkyl substances.
A breakdown product of these active substances, namely TFA (trifluoroacetic acid), is indeed a perfluoroalkyl substance. However, active substances are approved only if the effects of breakdown products such as TFA also meet the standards. Moreover, TFA is also an important degradation product of numerous other products that are not plant protection products.
There are also a number of other ingredients present in plant protection products on the Belgian market that are PFAS. This concerns only three ingredients present in five products:
- Two of those ingredients are perfluoroalkyl substances present in three identical plant protection products. Belgium has notified one of those ingredients at EU level to be banned because it does not meet the persistence criteria for co-formulants. The other ingredient still meets them. Sales figures for the last five years show that an average of 82 kg of these perfluoroalkyl substances are released into the environment per year through use as plant protection products. The authorisation holder, at the request of the public service, has now announced to remove these substances from the formulation.
- The third ingredient is a polyfluoroalkyl substance used as a propellant in two identical plant protection products. An average of 232 kg/year of that ingredient is released into the environment this way, but based on available scientific information, it is considered non-persistent, non-bioaccumulative and non-toxic. However, it does fall under the new European Regulation 2024/573 on fluorinated greenhouse gases, and will be phased out in application of this legislation.
5.#How toxic is the breakdown agent TFA?
Trifluoroacetic acid (TFA) is currently considered a substance of low toxicity, both to humans and the environment. Its possible presence in groundwater is not problematic for human health. This explains why no maximum standards have been imposed at present either.
However, an application has been submitted at European level to review this, and this is based on study results indicating possible adverse developmental effects in the rabbit following exposure to TFA.
Follow-up studies are needed to determine the human relevance of these developmental effects that may be specific to rabbits. Only after completion of European decision-making can these be taken into account in the approval of active substances of plant protection products (and other products to be registered).
If TFA is effectively found to have adverse effects on human development, the active substances that break down into TFA will probably no longer meet the conditions for approval. In that case, Belgium will urge the European Commission to have the active substances in question re-evaluated.
6.#Do PFAS in plant protection products pose a risk to public health or the environment?
Plant protection products (including polyfluorinated ones) are strictly controlled for their safety to human health and the environment. The maximum concentration that can be present on a crop is determined, taking into account the authorised uses and in such a way that there is no negative impact on consumer health.
In short, based on current knowledge, the safety margin between residue levels in food and possible effects in consumers is sufficient.
Also for environmental exposure, it is guaranteed for all plant protection products that their concentrations in the environment only have effects below the legal standards.
PFAS from plant protection products do not necessarily have the same environmental or health impact as PFAS from other sources, given the diverse group of PFAS.
It should be emphasised that an active substance is only approved if it is not characterised as a very persistent and very bioaccumulative substance (vPvB). The legislation on plant protection products thus very explicitly prevents such substances from being sold and used.
For the other ingredients besides the active substances, only a very limited evaluation is taking place. Given the low volumes involved, and the fact that the perfluoroalkyl substances concerned will be removed from plant protection products, no additional actions are planned for this at present.
7.#What is being done at European level to reduce the risks posed by PFAS?
The European Commission has made a proposal to restrict the use of PFAS. Currently, this proposal foresees that PFAS would be banned except for some exceptions, such as pharmaceuticals, active substances for plant protection products and the like. This proposal is still pending and is a source of scientific debate.
This would result in the disappearance of PFAS as coformulants of plant protection products (their occurrence in these is extremely limited), but thus not necessarily as active substances.
The reason why exemptions are provided for some categories of substances is that these categories are subject to a strict authorisation framework, which excludes an unacceptable risk for a substance. Thus, for all active substances of plant protection products, persistence, toxicity and bioaccumulation are evaluated prior to any authorisation.
On 12/01/2021, the Directive on the quality of water intended for human consumption came into force. It imposes a maximum concentration in drinking water of 0.5 µg/l for all PFAS combined, and an even lower standard of 0.1 µg/l for specified PFAS considered risky for human consumption. According to this legislation, the European Commission had to provide an analytical method for this by 12/01/2024, and Member States have to take measures by 12/01/2026 to ensure that water for human consumption meets this requirement. Implementing this legislation is a regional competence in Belgium. It is important to note that this limit is not specific to PFAS originating from plant protection products, but to PFAS in general.
In addition, Europe has provided for general maximum limits for PFAS in food (also for PFAS not originating from plant protection products) through EU Regulation 2023/915.
8.#Is Belgium taking additional measures for plant protection products?
Regarding active substances, Belgium awaits European measures and will implement them when they are in place. In Belgium, plant protection products containing PFAS are evaluated according to existing legal criteria, ensuring acceptable use. Active substances authorised in application of European legislation cannot simply be banned nationally, even if they contain PFAS.
With regard to other ingredients in plant protection products, Belgium is also awaiting the general ban of PFAS at EU level, which will then be translated into the inclusion of PFAS on the list of banned ingredients so that they will disappear from the composition of plant protection products throughout the EU.
However, the Federal Government fully supports the initiative to further refine the risk assessment of TFA (see question 5) based on field measurements and any new data of concern that will be followed up on a regular basis, as for all other plant protection products.
9.#Is the share of plant protection products in total PFAS use important?
In Belgium, according to a report dated December 2023, an 8330 tons of PFAS would be used on an annual basis.
Based on sales figures of plant protection products, we can state that the share of PFAS active substances in this is less than 5%, and of other PFAS ingredients in plant protection products less than 0.01%.
10.#Where can I find more information on PFAS?
- The website of the European Chemical Agency (ECHA): https://echa.europa.eu/hot-topics/perfluoroalkyl-chemicals-pfas
- The website of the European Commission: https://food.ec.europa.eu/safety/chemical-safety/contaminants/catalogue/pfass_en
- The report by the FPS Economy in cooperation with the FPS Public Health: https://economie.fgov.be/sites/default/files/Files/Entreprises/pfas-belgian-industry-market-study-final-public-report.pdf
- Sciensano's study of the presence and concentrations of a wide range of PFAS in food. https://www.sciensano.be/fr/sujets-sante/substances-et-polyfluoroalkylees-pfas
- FASFC FAQ: https://favv-afsca.be/nl/pfas-veel-gestelde-vragen
- An OECD report: About PFASs - OECD Portal on Per and Poly Fluorinated Chemicals