PFAS in Pesticides
‘Forever pesticides’
Fidra’s current work focuses on the use of per- and polyfluoroalkyl substances (PFAS) in pesticides, highlighting the serious risks that this practice presents. PFAS in the environment have been shown to accumulate in the tissues of many wildlife species, harm pollinators, damage soil health, and persist in ecosystems for decades — leading to long-term contamination of land and water resources.
Despite these risks, PFAS are amongst some of the most widely used pesticide active substances in the UK [1]. There are currently at least 30 known PFAS active ingredients approved for use in pesticides in Great Britain. Six of which have been identified as highly hazardous [2], [3], [4]. Lack of current regulation is causing farmers to unknowingly pollute their land with harmful forever chemicals, endangering themselves, their consumers, and the environment. With growing concerns over the widespread contamination and public health impacts of PFAS, urgent action is needed to regulate their use in agriculture.
Why are PFAS in pesticides?
Active ingredients refer to the substances that control, repel and kill the target pest. Many PFAS in pesticides can directly disrupt biological processes, proving highly toxic towards insects, microbes and plant species [2], [5]. The chemical properties of PFAS can also lead to greater target organisms’ specificity, faster action and prolonged residual activity [6].
The table below shows known PFAS active substances approved for use in Great Britain, the EU, and Denmark.
This table was compiled by searching for PFAS active substances approved for use in the EU (as identified by PAN EU in July 2025) within HSE’s register for active substances approved for use in pesticides in Great Britain. Northern Ireland continues to follow EU legislation on plant protection products (PPP) under the EU Withdrawal Agreement’s Windsor Framework.
Last updated: December 2025
Pesticides also include ‘inert’ ingredients or co-formulants, which help the formulation work. PFAS can be added to help with pesticide application, acting as propellants in aerosols, reducing uneven spraying, and facilitating greater penetration into target species [7], [8]. As pesticide inert ingredients are not required to be disclosed by manufactures, PFAS-containing pesticides may be being applied to land without the user’s knowledge. Inert ingredients are assumed to be non-toxic, but research indicates that inert substances in pesticides can also be lethal to pollinators [9].
PFAS may also inadvertently contaminate pesticides through the containers in which they are stored and manufacturing processes. For example, many pesticides, like other industrial and household products, are stored in high-density polyethylene (HDPE) containers, which can be lined with PFAS to enhance durability [10]. However, multiple cases of PFAS contamination in pesticides have been reported that are consistent with leaching from these containers [11].
Additionally, studies have shown that glyphosate, the most widely used pesticide in the world, can contain PFAS and other trace elements sold in some countries [36]. This PFAS has been found to be introduced through manufacturing processes, raw materials, or packaging rather than deliberate addition to the formulation.
Together, these examples show how the lack of a group-wide PFAS restriction is leading to the unintentional contamination of our environment with harmful ‘forever chemicals.’
Environmental risks of PFAS in pesticides
PFAS are frequently associated with harmful environmental effects due to their extreme persistence. Because PFAS don’t breakdown, these chemicals continue to travel through the environment and accumulate in ecosystems, meaning their negative impacts can be wide-ranging and long-term. Soil is a major sink for chemicals in the environment, including PFAS from pesticides. When inhabiting contaminated soil, organisms can absorb and accumulate PFAS [12]. PFAS have also been shown to alter microbial activity, leading to a significant increase in pH and modifying growing conditions [13]. Overall, PFAS can alter soil microbial communities and reduce the biodiversity and connectivity of soil bacteria, all of which can impact crop yields[14], [15].
Unhealthy and contaminated soil means unhealthy agricultural ecosystems. PFAS pesticides are not only toxic to the organisms they target, but exposure can impact a wide range of invertebrate species [16]. Existing research consistently reports negative outcomes, with bees being particularly vulnerable to chemical contaminants [17]. PFAS can accumulate in pollen, posing a significant risk to bee species by disrupting hormone regulation [18]. With few ecological studies investigating the direct effects of PFAS exposure, we need a more precautionary approach when considering the chemical cocktails being directly applied to land.
PFAS from pesticides don’t just affect our fields but have an easy pathway to runoff and enter our waterways. The persistence and mobility of PFAS means it is virtually impossible to contain them, with numerous negative outcomes. Research has shown forever chemicals to bioaccumulate in freshwater macro invertebrates and fish species [19] and PFAS have demonstrated toxicity for algae and crustaceans [20]. PFAS in waterways also threaten drinking water supplies, contributing to human exposure and potential health risks.
Health risks of PFAS in pesticides
The negative health effects associated with PFAS are well documented, and their use in pesticides provides yet another pathway for exposure through our food and water supply. Recent research has shown that fruit and vegetables in the UK and across the EU are becoming more and more likely to be contaminated with residues from PFAS pesticides[2] [21]. As PFAS pesticides become increasingly common, analysis reveals that the prevalence of PFAS residues has almost tripled between 2011 and 2021 across the EU. Some samples of strawberries and peaches had contamination rates as high as 37% and 35% respectively. Diet and drinking water are major pathways through which people are exposed to PFAS, with numerous negative health impacts [22], [23]. For example, dietary exposure to PFAS has been connected with adverse effects on the human immune system [24], the liver [25] and other chronic health impacts [26].
Trifluoroacetic Acid (TFA)
As well as posing risks in their own right, PFAS can break down into smaller molecules that have their own distinctive risks. Trifluoroacetic acid (TFA) is a short chained PFAS that is a common breakdown product of other larger PFAS used in pesticides [27]. TFA is very mobile, allowing it to spread quickly, especially through the water cycle [5], [6]. Left unchecked, environmental concentrations of TFA will continue to rise and there are growing scientific concerns over the impact this may have on human health or environmental processes [28], [29], [30], [31]. TFA is readily absorbed by the body and has been shown to be a reproductive toxicant in mammals [32], and is classified as harmful to aquatic life [33] Research in the EU has found TFA to be widespread in surface water [34], ground water [34], drinking water [29] and even bottled mineral water [35].
Our work on PFAS in pesticides
Currently, there are at least 30 PFAS active substances approved for use in Great Britain, including those recently withdrawn by Denmark for their association with TFA formation. In 2026, Fidra investigated PFAS pesticide use in the UK agricultural sector during 2023 and 2024. The key findings from this work were as follows:
PFAS active substances remained widely used across UK agricultural sector in 2023 and 2024, making up on average 14% of the top 50 most commonly applied pesticides (largely unchanged from 13% in 2021 and 2022).
From 2014 to 2024, the top 5 most used PFAS active substances in the arable sector were applied to over 41 million hectares, an area greater than the size of Paraguay.
PFAS active substances recently withdrawn in Denmark have been applied to more than 34 million hectares of UK arable crops between 2014-2024 (an area greater than the size of Finland).
It is important to note that this work only covered PFAS as ‘active’ ingredients. Pesticide products may also contain PFAS as ‘inert’ ingredients, however this information is not currently required to be disclosed by manufacturers.
Removing forever chemicals from pesticides and society
Fidra is calling on the UK Government to align with EU chemical regulation and commit to a universal restriction on PFAS. With over 10,000 PFAS, only with a wide-reaching ban can we prevent further environmental harm via regrettable substitution. A greater variety of PFAS means more uncertainty of their acute environmental effects and gives rise to the potential for more ‘cocktail’ effects – whereby chemical harms are exacerbated when different compounds mix in the environment.
We are also working with farmers to understand the challenges and opportunities in transitioning away from chemical inputs. Our farmer case studies showcase farmer attitudes towards PFAS pesticides, the challenges they are facing and some of the brilliant work they are already doing to reduce pesticide use. Visit our farmer hub for more information.
A call for urgent action
‘Forever chemicals’ threaten both public and environmental health, as well as the long-term productivity of UK agricultural land, with no sustainable solution for remediation. From the widespread pollution of UK rivers to contamination of local wildlife, it is well established that action must urgently be taken to reduce pesticides and wider chemical pollution, as outlined in the UK’s Environmental Improvement Plan, 2023.
We are calling on the UK Government to recognise the significant threat PFAS pesticides presents to public and environmental health and to commit to a group-based restriction on all non-essential uses of PFAS, including use in pesticides. This should be accompanied by effective support for the agricultural sector to transition away from chemical inputs and towards more sustainable practises, such as integrated pest management, wherever possible, and where pesticides are still used, these should come with full transparency of both active and inert ingredients.
Resources
Management of PFAS pesticides – Danish Case Study
This case study reveals how Denmark is leading the way to phase out ‘forever chemicals’ in pesticides and beyond, and what the UK can learn from their approach.
Published: December 2025
Authors: Fidra
Hidden chemical contaminants in agriculture – Farmer Resource
Learn how hidden chemical contaminants like PFAS in pesticides and sewage sludge are damaging soil health, threatening farm productivity, and wider environmental health. Download this resource to find out what action we urgently need from the UK Government to help farmers protect their land.
Published: July 2025
Authors: Fidra
Concentrations of Trifluoroacetic Acid (TFA) in UK Surface Waters
This study monitored TFA concentrations at 54 locations covering 32 rivers across the UK and throughout all seasons. The study aimed to determine whether TFA was present in UK surface water and to establish the degree of contamination compared to findings in other countries.
Published: June 2025
Author: Fidra
PFAS Active Substances in UK Pesticides
This report investigates the use of PFAS as an active pesticide substance in the UK, with particular focus on the UK arable sector. Pesticide active substances present a direct route for PFAS into the environment, threatening soil health and productivity. PFAS are known to alter soil microbial communities and reduce the biodiversity and connectivity of soil bacteria, all of which can impact crop yields.
Published: July 2024
Author: Fidra
Forever Chemicals in Pesticides Factsheet
Explore key facts about the usage and impacts of PFAS pesticides. Use of PFAS in pesticides provides a direct source of environmental contamination, risking soil health and productivity for future generations.
Published: July 2024
Author: Fidra
Farmer Case Study: Sustainable farming for healthy soils
This case study explores how farmer, Philip Sheane, avoids chemical contamination in farming. After growing concerns over the impacts chemical inputs may have on his health, his livestock, and his soil, Philip began investigating regenerative farming practices.
Published: December 2024
Author: Fidra
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