Axe 1 – Use of SDHI and alternatives

Agronomy, economy

Rémy Ballot and Marion Desquilbet

We are reviewing the worldwide scientific literature describing the past and current agronomic uses of the main SDHI active substances and their chemical and agronomic alternatives. We will then present an overview of SDHI uses in France. It will describe their effects on yield and on the costs of fungicides, energy and labour, as well as alternative practices ranging from fungicide substitution to the redesign of cropping systems.

Axe 2 – Mechanisms of toxicity in rodents

Toxicology, physiology
Erwan Bézard, Colette Denis

We are studying the mechanisms of SDHI toxicity in vivo in rodents, focusing on mitochondrial function and energy metabolism. We evaluate the impact of dysfunctions linked to an alteration of mitochondrial and metabolic functions on physiology, and their association with the development of neurodegenerative, renal and intestinal diseases.

Axe 3 – Mechanisms of toxicity in humans

Toxicology, biology
Sylvie Bortoli, Judith Favier, Thierry Gauthier

In humans, genetic inactivation of SDH by mutations leads to partial or total blockage of its activity, resulting in the development of severe pathologies (neuropathies, kidney diseases, cancers). Exposure to SDHI could lead to chemical inactivation with effects comparable to those observed in subjects with SDH genetic mutations. Thus, using cellular models, we aim to determine whether exposure to these pesticides may cause known alterations linked to SDH, such as epigenetic deregulations, metabolic reprogramming and/or oxidative stress. These mechanisms could be associated with the onset of chronic diseases.

Axe 4 – Human exposure and pathologies

Exposures and epidemiology
Jean-Marc Bonmatin, Pierre Lebailly, Joost Schanstra

Sensitive and reliable analytical methods are developed to measure actual exposure to SDHI. They will be used to measure human exposure through food (beverages, fruits, cereals, vegetables, etc.). Some exposures related to bee health will also be measured (honey, pollen).

On the epidemiological level, we are seeking to determine whether urinary SDHI levels in cohorts of farmers and subjects from the general population are correlated with the incidence of cancers and chronic kidney diseases.

Axe 5 – Impacts of SDHI on target organisms
Cécile Ménez, Olivier Puel

SDHI are used against pathogenic fungi, but also against certain worms (nematodes). We study the effect of SDHIs on the synthesis of mycotoxins produced by pathogenic fungi and toxicity in nematodes. These effects are compared with those observed in non-target organisms, in order to question the specificity of these substances.

Axe 6 – Impacts of SDHI on non-target organisms

Frédéric Delbac, Séverine Jean, Christophe Roux

SDHI are persistent in air, water and soil. They target a process that is widely conserved in living organisms: cellular respiration. Thus, like the target organisms, all other living beings are potentially subject to alterations in mitochondrial function and energy metabolism. We are studying these mechanisms in vivo, particularly in certain species of fish, soil fungi, as well as in the honeybee.

Axe 7 – Risk assessment and regulation of SDHI

Sociology and history of science, economics
David Demortain, Marion Desquilbet, Nathalie Jas

We are interested in the risk assessment methods applied to pesticides, the controversies surrounding them and their possible evolution or reform. We study the knowledge mobilised in the regulatory procedures to assess the off-target effects of pesticides and the delays in taking into account public research data in these procedures. In particular, we analyse the practices and tools used to assess the carcinogenicity of pesticides, the arguments put forward to explain their modes of action, the limitations of standard methods and their possible alternatives.

Cross-cutting theme

Network animation and knowledge co-construction
Jean-Marc Bonmatin, François Chamaraux, Laurence Huc

In order to produce knowledge according to the EcoHealth, approach, we set up a scientific animation through the organisation of workshops and transversal seminars – internal or public.

We ensure the scientific and ethical coordination and management of the data produced within the different research axes. The results are brought together in order to obtain an integrated vision of the issue of SDHIs use.

Some keys to understanding