Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
In order to perform a human and ecological risk assessment of pharmaceutical products (PPs) in natural waters, it is necessary to accurately quantify a broad variety of PPs at low concentrations. Although numerous currently implemented analytical methodologies, less is known about the preservation of PPs in natural water samples within the period before analysis (holding time, storage conditions). This paper is the first literature review about the stability of PPs in natural waters (surface and groundwaters) during sample storage. The current work focuses on a comparison of the performances of the available preservation techniques (filtration, container materials, storage temperature, preservative agents, etc.) for PPs in samples. All 58 reviewed PPs may be successfully stabilized during 7 days in surface waters by at least one appropriate methodology regarding temperature, acidic and non-acidic preservatives. When temperature is not a sufficient preservation parameter f! or some PPs (hormones and fluoxetine) its combination with the addition of chemical agents into the samples may prolong the integrity of the PPs during storage in surface water. There is a strong need to use standard protocols to assess and compare the stability of PPs in environmental water matrices during storage as well as during analytical preparation or analysis (European criteria 2002/657/EC). Since the stability of PPs during sample storage is a critical parameter that could call into question the quality of the data provided for the concentrations, the design of stability studies should rigorously take into account all critical parameters that could impact the concentrations of the PPs with time.
Talanta

insu-00839186
https://hal-insu.archives-ouvertes.fr/insu-00839186
DOI : 10.1016/j.talanta.2013.01.042

Éditeur(s) : HAL CCSD Elsevier
Résumé : absent
ISSN: 0034-4257

hal-01019844
https://hal.archives-ouvertes.fr/hal-01019844
DOI : 10.1016/j.rse.2012.03.012

Éditeur(s) : HAL CCSD Elsevier
Résumé : Vegetation phenology is the study of the timing of seasonal events that are considered to be the result of adaptive responses to climate variations on short and long time scales. In the field of remote sensing of vegetation phenology, phenological metrics are derived from time series of optical data. For that purpose, considerable effort has been specifically focused on developing noise reduction and cloud-contaminated data removal techniques to improve the quality of remotely-sensed time series. Comparative studies between time series composed of satellite data acquired under clear and cloudy conditions and from radiometric data obtained with high accuracy from ground-based measurements constitute a direct and effective way to assess the operational use and limitations of remote sensing for predicting the main plant phenological events. In the present paper, we sought to explicitly evaluate the potential use of MODerate resolution Imaging Spectroradiometer (MODIS) remote sensing data for monitoring the seasonal dynamics of different types of vegetation cover that are representative of the major terrestrial biomes, including temperate deciduous forests, evergreen forests, African savannah, and crops. After cloud screening and filtering, we compared the temporal patterns and phenological metrics derived from in situ NDVI time series and from MODIS daily and 16-composite products. We also evaluated the effects of residual noise and the influence of data gaps in MODIS NDVI time series on the identification of the most relevant metrics for vegetation phenology monitoring. The results show that the inflexion points of a model fitted to a MODIS NDVI time series allow accurate estimates of the onset of greenness in the spring and the onset of yellowing in the autumn in deciduous forests (RMSE <= one week). Phenological metrics identical to those provided with the MODIS Global Vegetation Phenology product (MDC12Q2) are less robust to data gaps, and they can be subject to large biases of approximately two weeks or more during the autumn phenological transitions. In the evergreen forests, in situ NDVI time series describe the phenology with high fidelity despite small temporal changes in the canopy foliage. However, MODIS is unable to provide consistent phenological patterns. In crops and savannah, MODIS NDVI time series reproduce the general temporal patterns of phenology, but significant discrepancies appear between MODIS and ground-based NDVI time series during very localized periods of time depending on the weather conditions and spatial heterogeneity within the MODIS pixel. In the rainforest, the temporal pattern exhibited by a MODIS 16-day composite NDVI time series is more likely due to a pattern of noise in the NDVI data structure according to both rainy and dry seasons rather than to phenological changes. More investigations are needed, but in all cases, this result leads us to conclude that MODIS time series in tropical rainforests should be interpreted with great caution. (C) 2013 Elsevier Inc. All rights reserved.
ISSN: 0034-4257

hal-01032407
https://hal.archives-ouvertes.fr/hal-01032407
DOI : 10.1016/j.rse.2013.01.010

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Veterinary pharmaceuticals, widely used in intensive livestock production, may contaminate surface waters. Identifying their sources and pathways in watersheds is difficult because i) most veterinary pharmaceuticals are used in human medicine as well and ii) septic or sewer wastewater treatment plants (WWTP) can release pharmaceuticals into surface water, even in agricultural headwater watersheds. This study aimed to analyze the spatiotemporal variability of animal-specific, mixed-use, and human-specific pharmaceuticals, from agricultural headwaters with intensive livestock production and a WWTP to a watershed used for Water Framework Directive monitoring. Grab sampling was performed during one hydrological year upstream and downstream from a WWTP and at three dates in seven nested watersheds with areas of 1.9-84.1km2. Twenty pharmaceuticals were analyzed. Animal-specific pharmaceuticals were detected at all sampling dates upstream and downstream from the WWTP and at concentrations higher than those of human-specific pharmaceuticals. The predominance of animal-specific and mixed-use pharmaceuticals vs. human-specific pharmaceuticals observed at these sampling points was confirmed at the other sampling points. Animal-specific pharmaceuticals were detected mainly during runoff events and periods of manure spreading. A large percentage of mixed-use pharmaceuticals could come from animal sources, but it was difficult to determine. Mixed-use and human-specific pharmaceuticals predominated in the largest watersheds when runoff decreased. In areas of intensive livestock production, mitigation actions should focus on agricultural headwater watersheds to decrease the number of pathways and the transfer volume of veterinary pharmaceuticals, which can be the main contaminants
ISSN: 0048-9697

insu-01574739
https://hal-insu.archives-ouvertes.fr/insu-01574739
DOI : 10.1016/j.scitotenv.2017.07.206
PUBMED : 28783916

Éditeur(s) : HAL CCSD
Résumé : International audience
Diffuse contamination of surface water by veterinary pharmaceuticals (VP) has been poorly studied in intensive breeding context. Recycling animal waste on soil is supported to fertilize crops and reduce utilization of mineral fertilizer but may have some environmental impact by recycling pollutants on soils and transferring pollutants from soils to rivers. Most of pharmaceuticals are consumed indifferently by human and animal, especially antibiotics. This study aims to quantify veterinary pharmaceuticals (VP) in superficial water in two agricultural catchments. One is dedicated to the production of drinkable water. Agriculture but also waste water treatment plant may contribute to the contamination of water and it is difficult to distinguish animal versus human source of contamination
1ere conférence internationale sur l’évaluation des risques des résidus de médicament dans l’environnement
Paris, France

insu-01467591
https://hal-insu.archives-ouvertes.fr/insu-01467591

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The cyanobacteria-derived neurotoxin β-methylamino-l-alanine (BMAA) represents a plausible environmental trigger for amyotrophic lateral sclerosis (ALS), a debilitating and fatal neuromuscular disease. With the eutrophication of water bodies, cyanobacterial blooms and their toxins are becoming increasingly prevalent in France, especially in the Brittany region. Cyanobacteria are monitored at only a few recreational sites, preventing an estimation of exposure of the human population. By contrast, phosphorus, a limiting nutrient for cyanobacterial growth and thus considered a good proxy for cyanobacteria exposure, is monitored in many but not all surface water bodies. Our goal was to develop a geographic exposure indicator that could be used in epidemiological research. We considered the total phosphorus (TP) concentration (mg/L) of samples collected between October 2007 and September 2012 at 179 monitoring stations distributed throughout the Brittany region. Using readily available spatial data, we computed environmental descriptors at the watershed level with a Geographic Information System. Then, these descriptors were introduced into a backward stepwise linear regression model to predict the median TP concentration in unmonitored surface water bodies. TP concentrations in surface water follow an increasing gradient from West to East and inland to coast. The empirical concentration model included five predictor variables with a fair coefficient of determination (R2 = 0.51). The specific total runoff and the watershed slope correlated negatively with the TP concentrations (p = 0.01 and p < 10− 9, respectively), whereas positive associations were found for the proportion of built-up area, the upstream presence of sewage treatment plants, and the algae volume as indicated by the Landsat red/green reflectance ratio (p < 0.01, p < 10− 6 and p < 0.01, respectively). Complementing the monitoring networks, this geographical modeling can help estimate TP concentrations at the watershed level, delivering a proxy for cyanobacteria exposure that can be used along with other risk factors in further ALS epidemiologic case–control studies
ISSN: 0160-4120

hal-01175538
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01175538
DOI : 10.1016/j.envint.2015.04.007
PUBMED : 25913322