Strawberry growers are unaware that the plant protection products they use may contain PFAS. Research shows that. Dutch growers were asked about their crop protection choices and their knowledge of the substance group that they know about from mainstream news, but about which they have very little knowledge specifically focused on the crop protection products they use.
PFAS, short for poly- and perfluoroalkyl substances, are often added to crop protection products, the researchers know. Well-known products for Dutchs growers such as Flint, Luna, Switch, Sivanto, Bifasto and Takumi contain PFAS as active ingredients. In response to a parliamentary investigation, the responsible minister revealed just this winter that 105 crop protection products contain PFAS.
In plant protection products, PFAS helps improve the effectiveness of plant protection products, for example. The substances are also found in crop protection product adjuvants, where PFAS can help lower surface tension.
Growing concerns
Among scientists, concerns about PFAS and their impact on the environment, ecosystem and public health do grow. Growers themselves are not worried about health risks as long as concentrations remain low.
Commissioned by the Wetenschapswinkel of Wageningen University and Research (WUR), 6 students interviewed 10 strawberry growers in the Netherlands to gain insight into their views, preferences, and other factors that play a role in making choices about crop protection products and PFAS. These interviews revealed the challenges and considerations experienced by growers in making these important decisions for their operations.
For PFAS to eventually disappear from crop protection products, clear product information, support for alternative solutions and promotion of PFAS-free cultivation practices by advisers are essential, according to the researchers.
Transparency and regulation
The researchers note from their interviews that strawberry growers' knowledge of PFAS is limited. They see a lack of transparency towards growers. This is largely due to the fact that producers are not obliged to explicitly state which chemicals their products contain.
The Ctgb (Board for the Authorisation of Plant Protection Products and Biocides) has a crucial role in this, the authors believe. The Ctgb evaluates and approves crop protection products based on safety criteria, but there is little information available on how specifically PFAS are included in this, the researchers argue. They call for stricter regulations on the use of PFAS.
The Ctgb does recognize the societal concerns about PFAS, according to a publication on their website. In a European context, the Netherlands, Germany, Denmark, Sweden and Norway proposed a total ban on the production, use and sale of PFAS in 2023. This did make an exception for active substances in plant protection products, biocides and (animal) medicines, as "these products are already strictly assessed."
In the Netherlands, the Ctgb is responsible for that. In response to the EU proposal, it writes: "The restriction proposal for PFAS advises the European Commission to take more account of persistence in the authorization procedure for plant protection products and biocides. It is currently being examined at European level how this recommendation can be put into practice."
This spring, it was not yet known when the European restriction would take effect. The European Commission wants to eventually ban the use of PFAS. Especially for adjuvants, this will have consequences. These will be phased out, the minister shared with the House of Representatives.
Importance of advisers
The researchers also advocate requiring producers of plant protection products to provide full information on the contents of their products. "That is crucial for making safer choices," they said.
A quote from a grower interviewed shows why this is important. When asked whether the presence of PFAS in a crop protection product affects the grower's choice of use, it was heard: "No, because I don't know what it does contain. If I did know, that would be an additional consideration factor. There might come a moment that I will have powdery mildew in my crop and I have a choice between an agent containing PFAS I only have to spray once, or other agents have to be applied four times. Is PFAS so harmful that I then have to spray four times with another pesticide?"
On the PFAS issue, the Wageningen students point additionally to the importance of crop advisers, in whom growers have great confidence, according to the talks. "They play an essential role in providing good advice to growers on crop protection products. We consider their advice and expertise an indispensable factor for the success of the transition to PFAS-free cultivation. Advisers should specifically look out for independent and safer choices for the grower."
The minister already advocated independent advisers on crop protection last year. The plan was also included in the Coalition Agreement. A few months after his proposal, the cabinet fell. At the moment, a new minister is in charge of agriculture.
Away from PFAS
There are options to switch to PFAS-free cultivation, and growers know those options too. In fact, many growers already use biological pesticides such as Cucumeris, Tracer, Serenade and chemical crop protection agents without PFAS such as Captan, Batavia and Signum. Some growers are also showing interest in alternative cultivation methods, such as the use of nets against insects and technologies such as UV-C radiation against mildew and robotization. These innovations also reduce workload and costs.
Furthermore, switching to strawberry varieties that are resistant to pests and diseases can also contribute to PFAS-free cultivation, thus reducing the need for chemical plant protection products. This offers a double win, the researchers stress: the environment is less affected and growers can save costs in the long run.
Some growers are considering or have already made the switch to another variety. Varieties that are resistant to common diseases such as mildew and Botrytis need less plant protection products. Growers then rely less on plant protection products containing PFAS.
Challenges
The transition to PFAS-free cultivation does come with challenges. For instance, growers indicate that the list of authorised crop protection products is decreasing and not enough new products are coming online. Growers are open to alternatives, but only if they are as effective in protecting their strawberries. According to them, there is currently a limited supply of good alternatives, which prevents the switch to PFAS-free cultivation.
Not every grower is confident about going full on organic when it comes to crop protection products. One grower does have confidence in organic agents, but quips that apparently this does not automatically apply to everyone: "If a new chemical agent is introduced now, there is always much confidence in it, but organic agents have to prove themselves." It sometimes surprises this grower that seemingly much more extensive testing is required for agents that have already proven themselves in nature, compared to chemical agents. As far as he is concerned, this should be more equivalent.
It further emerged that growing new strawberry varieties with high disease resistance is seen by growers as a necessary step towards reducing chemical protection agents and eventually PFAS-free cultivation. However, new strawberry varieties may also bring uncertainties. They may not perform as well under a grower's specific soil and climate conditions, or they may not fit well with existing cultivation methods.
More importantly, interviews reveal, consumers may not prefer some varieties, making it difficult for growers to sell them. Growers have to meet strict consumer demands, especially on the shape and taste of strawberries. For growers, it is important that new varieties are easy to grow with preferably less labour and good yields.
Will to change
The survey shows that most growers are positive about a greener future by switching to PFAS-free crop protection products. Although there are financial risks, the switch offers opportunities for innovation and sustainability. To eventually eliminate PFAS from crop protection products, clear product information, support for alternative solutions and promotion of PFAS-free agricultural practices by advisers are essential. Involving growers in discussions with other stakeholders, such as government and crop protection product manufacturers, is crucial to facilitate this transition to PFAS-free alternatives, according to the researchers.
The researchers only spoke to strawberry growers, but have an idea of how it applies to other crops. Thijmen Calis, one of the researchers: "We really noticed how every grower is already doing their best to do as much organic as possible. We saw that coming back again and again. So we do expect that the strawberry grower will not be alone in trying to grow the greenest crop possible."
The authors of the study are: Cathy van den Heuvel, Thijmen Calis, Elvin Lodder, Jori Huang, Penny Tsapikouni and Jesús Mariscal Gallardo.