Pesticides are a subject that concerns us all because it affects food. It is a subject under tension from a social, ecological, political and economic point of view. Since 2020, a long-term study has aimed to clarify the impacts of these pesticides on ecosystems and on living organisms. The results of this two-year research were published on 5 May 2022.
Result: the impact of these pesticides on the environment is confirmedAs we shall see in detail.
The study in question: two years of research into pesticides
The use of pesticides in agriculture is a thorny issue between environmental impacts and the capacity of the agricultural sector to meet the needs of the planet. In this sense, a long-term study was commissioned by three ministries from Inrae and Ifremer to be integrated into Ecophyto II +: the Ministry of Agriculture, the Ministry of Ecological Transition and the Ministry of Research.
Ecophyto II + is a government plan, in line with the EU directive 2009/128/EC, around the reduction of plant protection products and the withdrawal of glyphosate. The research was therefore commissioned to provide scientific data in support of this plan.
This research lasted two years and involved nearly fifty experts. It took the form of a collective scientific expertise, i.e. "a state of the art of scientific knowledge to date on a given social issue, commissioned by public actors, in support of public decision-making. The objective of these two years of hard work was therefore mainly to to produce a synthesis of all the knowledge available in France and in the world about plant protection products and their impact on living organisms and ecosystems.
This gathering of knowledge will then help to clarify the situation, make the data more meaningful and thus offer policy makers solid and comprehensive expertise for action. So what do these two years of expertise add up to?
Pesticides do have an impact on the environment
The press release from the study team is clear: "The conclusions of this study confirm that all terrestrial, aquatic and marine environments, particularly coastal ones, are contaminated by plant protection products. "Environments are therefore impacted, as are ecosystems and terrestrial, aquatic and marine life. Moreover, all these elements are impacted directly and indirectly, even if contamination with products that have been banned for several years is fortunately decreasing.
While contamination has been confirmed and identified, the work also provides some grey areas to be clarified. The research highlighted the need for better quantification of environmental impacts, better knowledge of impacts on ultra-marine and marine biodiversity and cocktail effects.
Total impact of pesticides
Whether directly or indirectly, pesticides therefore impact :
- Environments, ecosystems and the services they provide to society and biodiversity;
- Living organisms, whether or not they are targeted by the pesticide use.
On the environmental and ecosystem side, the impact and contamination could be accurately quantified thanks to the evolution of the substances sought and the detection, analysis and sampling capacities. This precision made it possible to highlight a global contamination of all environmentsThe report states that "there is widespread contamination of ecosystems by plant protection products in agricultural areas, soils, small waterways and the air, where they are mainly applied". Despite this, the areas around agricultural plots, sometimes thousands of kilometres away and even in areas of extreme cold, are also contaminated, as are aquatic environments and sediments. We find products banned today that are still present in peripheral areas, as markers of past use.
In this sense, the contamination of ecosystems and living organisms in their close relationships leads to a weakening of biodiversity and ecosystem services. For example, plant protection products used on agricultural land are directly linked to the falling populations of terrestrial and aquatic invertebrates such as pollinators. These essential elements of life are impacted directly by products, but also directly, as these products alter their food resources and habitats.
Finally, all of these impacts make plant protection products a In addition to the "aggravating factor on the health status of ecosystems, ranked 4th among direct aggravating factors [...] ahead of invasive alien species" and behind "land and sea use change, direct exploitation of organisms and climate change."
Levers as impact mitigation
The study not only highlighted the problems, but also raised effective levers to limit contamination and its impacts "while ensuring crop protection" such as levers "related to regulation, product use practices and the structure of agricultural landscapes.
On the one hand, legislation has been recognised as a lever The EU regulation "does not sufficiently take into account the complexity of the effects on biodiversity and underestimates the cocktail effect of substances that mix and accumulate in the environment, as well as their indirect effects. This EU regulation "does not sufficiently take into account the complexity of the effects on biodiversity and underestimates the cocktail effect of substances that mix and accumulate in the environment, as well as their indirect effects.
On the other hand, the notion of surveillance and monitoring is essential in order to have constant data to study and take into account for this "phytopharmacovigilance".
Finally, two important elements were highlighted as levers influencing the environmental impacts of the products used: the way the products are used and the landscape context of the place where the products are used.