Potential Toxicity of pesticides in Continental Aquatic Environments – PoToMAC
POTOMAC project brings strong innovation regarding new passive sampling strategies coupled with chemical and biological analyses. Initially, this project aims to develop a range of passive samplers to characterize the contamination levels of surface waters by diffuse pollution from agriculture. According to this metrological axis, we propose to develop innovative tools specifically dedicated to the sampling of hydrophobic or very hydrophilic pesticides (i.e. anionic herbicides), these classes of compounds have been very few, if not addressed since the onset of passive sampling techniques. We also seek to improve the performance of existing tools, for which some project partners have gained experience in recent years. For the different tools developed, we should be better informed for the application range, the exposure duration and the lag phase, especially compared to the peaks of contaminants. Key points to improve the estimates of time-weighted average concentrations of pesticides in natural waters will be addressed with a calibration and, then with the studying of the mechanisms of diffusion and both analyte accumulation and desorption kinetics. This work should ultimately provide the data necessary to quantify a wide range of pesticides.
In a second step, the tools developed will be deployed in representative freshwater systems (i.e. river and lake) in order to study on the one hand, the performance with field conditions and on the other hand, the improvement of either temporal or spatial representiveness. For this purpose, the passive sampling data will be compared with classical spot and automated sampling strategies. Besides the estimation of pesticide exposure in freshwater environments using these passive sampling techniques and innovative analysis, this project proposes to assess the impacts on aquatic communities, especially regarding to the algal and bacterial compartments in biofilms. These impacts will be assessed through the study of the acquisition of tolerance and adaptability of these communities in relation with the pressures associated with the pesticide toxicity. The relevance of passive samplers will be investigated to isolate classes of contaminants really involved in this toxicity.
Finally, we will address the issue for determining the potential toxicity of the fractions sampled by each tool during laboratory experiments. The goal is to assess, by using functional and structural descriptors, the impacts of pesticide mixtures selected by each type of passive sampler, this selectivity being due to both the organic / inorganic nature of contaminants, the range of polarity for organic compounds and the compartment sampled (mostly dissolved, or even colloidal). The results from this study should improve our knowledge on both design and validation of performing tools, and on the relevance of these passive samplers to estimate in situ exposure. A better knowledge and characterization of the fractions of potential toxicants in freshwaters, especially in relation with pesticides, their metabolites and the biological compartment covered in this project are also expected.
Nicolas MAZZELLA (INSTITUT DE RECHERCHE EN SCIENCES ET TECHNOLOGIES POUR L ENVIRONNEMENT ET L AGRICULTURE - IRSTEA) – firstname.lastname@example.org
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
UMR 5805 EPOC UNIVERSITE BORDEAUX I
UMR 5280 - LSA UNIVERSITE CLAUDE BERNARD - LYON I
INRA UMR CARRTEL INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE - CENTRE DE RECHERCHE DE DIJON
UR MALY INSTITUT DE RECHERCHE EN SCIENCES ET TECHNOLOGIES POUR L ENVIRONNEMENT ET L AGRICULTURE - IRSTEA
UR REBX INSTITUT DE RECHERCHE EN SCIENCES ET TECHNOLOGIES POUR L ENVIRONNEMENT ET L AGRICULTURE - IRSTEA
Help of the ANR 499,935 euros
Beginning and duration of the scientific project: February 2012 - 42 Months