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The agricultural activity presents the main source of the atmospheric contamination by pesticides. The occurrence of pesticides in the atmosphere concerns the research community due to their potential impacts on population and ecosystems. The volatilization from plants is higher and faster than the volatilization from soil. However, this transfer pathway is difficult to assess with few available models. The lack of knowledge on pesticide volatilization from plants is essentially linked to the complex interactions between processes occurring at the leaf surface and competing with volatilization, such as leaf penetration and photodegradation. This article presents a bibliographic synthesis of the state of knowledge on pesticide volatilization from plants, leaf penetration, photodegradation and control factors of these processes. Measuring methods and existing models describing these processes are also presented and analyzed | Les niveaux de concentration des pesticides dans l’atmosphère méritent une attention particulière de la part de la recherche compte tenu de leurs impacts potentiels sur la population et les écosystèmes. L’activité agricole constitue la principale source de contamination de l’atmosphère par les pesticides. Bien que la volatilisation depuis la plante soit reconnue plus intense et plus rapide que la volatilisation depuis le sol, cette voie de transfert est à ce jour la moins bien renseignée avec peu de modèles disponibles pour sa description. Le manque de connaissances est lié essentiellement à la complexité des interactions entre les processus ayant lieu à la surface de la feuille et qui sont en compétition avec la volatilisation, notamment la pénétration foliaire et la photodégradation. Cet article présente une synthèse bibliographique sur l’état des lieux des connaissances sur le processus de volatilisation des pesticides depuis un couvert végétal, de la pénétration foliaire et de la photodégradation, ainsi que les facteurs de contrôle de ces processus. Les méthodes de mesure ainsi que les modèles existants décrivant ces processus sont également présentés et analysés

International audience | Metabolic disorders induced by endocrine disruptors (ED) may contribute to amphibian population declines but no transgenerational studies have evaluated this hypothesis. Here we show that Xenopus tropicalis, exposed from the tadpole stage, to the ED benzo[a]pyrene (BaP, 50 ng.L−1) produced F2 progeny with delayed metamorphosis and sexual maturity. At the adult stage, F2–BaP females displayed fatty liver with inflammation, tissue disorganization and metabolomic and transcriptomic signatures typical of nonalcoholic steato-hepatitis (NASH). This phenotype, similar to that observed in F0 and F1 females, was accompanied by a pancreatic insulin secretory defect. Metabolic disrupted F2–BaP females laid eggs with metabolite contents significantly different from the control and these eggs did not produce viable progeny. This study demonstrated that an ED can induce transgenerational disruption of metabolism and population collapse in amphibians under laboratory conditions. These results show that ED benzo[a]pyrene can impact metabolism over multiple generations and support epidemiological studies implicating environmental EDs in metabolic diseases in humans.

International audience | The use of the Diffusive Gradient in Thin Film sampler (DGT) as a monitoring tool for regulatory programs is currently evaluated. In this context, the impact of commonly followed procedures on the accuracy of DGT-labile As, Cd, Cu, and Ni quantification was studied. Initial sampler contamination yields to define quantification limits instead of using blank subtraction, thus avoiding artifact concentrations. Not considering the alteration of element diffusion by the filter membrane leads to significant underestimation. However, diffusion coefficients determined on a non-fouled membrane were found to be suitable for the studied site, making it possible to use data from the literature. When diffusive boundary layer formation is neglected, no loss of accuracy is recorded provided the layer is thinner than 0.5 mm. Finally, exploration of potential biases allowed initiating a framework that might help limit inaccuracies in DGT-labile concentration estimation and interpretation, especially in a low contamination context.

International audience

International audience

International audience

International audience

International audience

International audience