Detection of Adsorbed Chlordecone on Microplastics in Marine Sediments in Guadeloupe: A Preliminary Study

Plastic pollution in the oceans is recognized as a worldwide problem. Since the 1950s, the production of plastics has been increasing and the first reports of microplastics (particles \u3c 500 μm) in the marine environment began to appear in the 1970s. These particles represent a growing environmental problem due to their dispersion in seawater and marine organisms. Additionally, microparticles in general can adsorb pollutants that will then become bioavailable to organisms by being desorbed during digestion, which could be an important pathway for the contamination of organisms. In Guadeloupe and Martinique, an organochlorine pesticide called “chlordecone” was used from 1972 to 1993 in banana plantations and this very persistent pollutant contaminates soils, rivers, and coastal marine areas and accumulates in marine foodwebs. To examine these issues, we had two goals: 1) to assess the contamination of marine sediments by microplastics surrounding Guadeloupe; and 2) to determine the ability of microplastics to adsorb chlordecone, as has been demonstrated for other organochlorine pollutants. To do so, marine sediments were collected in triplicate from 12 sites in coral reef environments around the island. Microplastics from each sample were then enumerated by size, color and shape under a binocular microscope. The results indicate that microplastics are found in all the studied sites and that their distribution could be linked to marine currents or proximity to areas of significant human activities (port activities, agglomeration, etc.). Finally, our preliminary results indicated that chlordecone could be adsorbed onto microplastics, with a concentration ranging from 0.00036—0.00173 µg/µg of microfilter

Variability of amphidromous organism isotopic niches in three Guadeloupe rivers affected by damming and water catchment

Native fauna of the tropical volcanic part of Guadeloupe is amphidromous: juveniles born in rivers but that grow in the sea need to migrate upstream to colonise their adult habitat in rivers. This migration is affected by any human-made obstacles placed in their way. Moreover, on volcanic tropical islands, streams are the main source of water catchment for the human population. This deeply affects river hydrology and characteristics. Both damming and water catchment potentially affect community diversity and species demography, but they may also alter the trophic ecology of the river fauna. Using stable isotopes and the stable isotope Bayesian ellipses approach in R (SIBER), this study aimed to assess the isotopic niche variability of riverine fauna of three persistent small rivers of Basse-Terre Island (Guadeloupe) affected by damming and water catchment. Using electrofishing, decapods and fishes (gobies) of three rivers were sampled upstream and downstream of dams. Our results demonstrated that the variability of the isotopic niches was extremely high between rivers but varied less between stations of the same river. Our results revealed complex and river-specific effects and a pattern merged with natural variability. Our two hypotheses (i.e., increase of resources upstream of dams and differential responses of trophic guilds to damming and water catchment) were only weakly supported and never in an unambiguous manner. Our study showed that it is necessary to consider the ‘noise’ generated by natural variability to observe and understand changes in the trophic ecology of associated fauna in relation to damming and water catchment.Réponses démographique et adaptative aux perturbations de continuité écologique chez les espèces amphidromes (Gobiidae et Palaemonidae) (2016-05/projet227)

Molecular Demonstration of a Pneumocystis Outbreak in Stem Cell Transplant Patients: Evidence for Transmission in the Daycare Center

Pneumocystis jirovecii pneumonia (PCP) is a life-threatening infection in hematology. Although occasionally reported, the role of interhuman transmission of P. jirovecii in PCP, compared to that of reactivation, remains an unresolved question; the recommendation to isolate PCP patients in the hematology ward are not well evidence-based. Following an unexpected increase in the number of febrile pneumonia patients with P. jirovecii DNA detected in respiratory samples in our hematology ward, we explored 12 consecutive patients from November 2015 to May 2016. Genotyping of P jirovecii was performed using microsatellite markers. The frequency of simultaneous occupancy of these 12 patients in the same unit on the same day from 4 months prior to the first diagnosis was recorded. In three patients, the P. jirovecii genotype could not be determined because DNA was insufficient. One rare single genotype (Gt2) was found in four of the other nine, all allogeneic stem cell transplant recipients. The transmission map showed that these 4 patients had multiple opportunities to meet on the same day (median, 6.5; range, 4–10) at the daycare center. It was much less among the eight non-Gt2 patients (median, 1; range, 0–9; P = 0.048). This study, based on modern molecular technics, strongly suggests that interhuman transmission of P. jirovecii between allogeneic stem cell transplant recipients is possible. P. jirovecii DNA detected in respiratory specimens supports that isolation and respiratory precautions be recommended in such cases in the hematology ward

Modèles et architectures d'interaction interne et externe pour cartes à microprocesseur ouvertes

La carte à microprocesseur a, en presque trente ans d'existence, conquis nos poches en rendant discrètement une multitude de services dans des domaines aussi variés que la finance ou la téléphonie. Aborder la carte à puce est un peu comme jouer à Tetris, jeu d'encastrement de polyominos. Ses contraintes matérielles sont si fortes qu'il faut arranger avec une compacité maximale les composants logiciels lui donnant corps. Son utilisation ne saurait se concevoir sans l'existence d'application cliente issue d'un système d'information réparti dans lequel elle s'intègre. Ceci induit alors un second type de puzzle, consistant à emboîter applications encartées et distantes, non trivial du fait des caractéristiques des cartes en termes de présence et de communication. L'émergence de cartes dites ouvertes, embarquant et exécutant plusieurs applications non-concurrentes, a enfin engendré un dernier type d'emboîtement, visant à faire coopérer plusieurs applications encartées.LILLE1-BU (590092102) / SudocSudocFranceF

Effects of dams on demographic structures of amphidromous fish and crustacean species in Caribbean rivers

International audienceCaribbean island rivers are the home to migratory indigenous macro-fauna. Concurrently, they also serve as the main source of freshwater for human consumption. This production of drinking water involves the construction of a large number of structures across the riverbed, which can slow or even stop the migration of aquatic species. The resident river macro-fauna is composed of crustacean and fish species that all have a diadromous and mostly amphidromous life cycle, involving pro-larval drift downstream towards the sea, marine larval dispersal, followed by an upstream river migration to complete their growth and reproduction cycle. Our study compares, across three rivers on the island of Guadeloupe, the recruitment of five crustacean species and two fish species in the mouths of these rivers with species demographic distributions on either side of the major water withdrawal structure built along these rivers. Post-larval recruitment events were multispecific, discrete over time and their amplitude varied depending on the river. We show differential biological porosity of each obstacle according to species, revealing different specific crossing abilities. Our results also suggested that the impacts were not directly related to the height of the structure but that external, hydrological and environmental, conditions are involved. These achievements can be translated into operational measures such as the maintaining and monitoring of reserved minimal flows that are adapted to passways, as well as the setting up of protective measures for the natural environment.Les rivières caribéennes sont le lieu de vie d’une macrofaune indigène migratrice et aussi le principal lieu de prélèvement pour la production d’eau potable pour la population humaine. Cette production d’eau potable impli-que la construction d’un grand nombre d’ouvrages en travers du lit des rivières, qui peuvent ralentir ou stopper la migration des espèces. La macrofaune résidente est composée d’espèces de crustacés et de poissons qui ont tou-tes un cycle de vie diadrome et majoritairement amphidrome, impliquant une dévalaison larvaire vers la mer, une dispersion larvaire marine puis une montaison en rivière pour terminer leur croissance et se reproduire. Notre étude porte sur la comparaison du recrutement de cinq espèces de crustacés et deux espèces de poissons dans les embouchures de trois rivières proches, ainsi que sur la distribution démographique des différentes espèces de part et d’autre de l’ouvrage majeur de ces trois rivières. Les recrutements sont multispécifiques, discrets dans le temps et leur importance est variable selon l’embouchure. La porosité biologique de chaque obstacle est diffé-rente en fonction des espèces révélant différentes capacités de franchissement. Nos résultats suggèrent aussi que les impacts ne sont pas directement liés à la hauteur de l’ouvrage mais qu’interviennent des conditions externes à celui-ci, hydrologiques et environnementales. Ces acquis peuvent se décliner en mesures opérationnelles comme l’importance du maintien et de la surveillance de débits réservés adaptés et maîtrisés au niveau des passes, ainsi que la mise en place de mesures conservatoires de la ripisylve et de l’environnement naturel proch

The invasive lionfish, Pterois volitans, used as a sentinel species to assess the organochlorine pollution by chlordecone in Guadeloupe (Lesser Antilles)

International audienc

Depth distribution of benthic dinoflagellates in the Caribbean Sea

International audienc

Spatio-temporal dynamics and biotic substrate preferences of benthic dinoflagellates in the Lesser Antilles, Caribbean sea

International audienc

Variability of amphidromous organism isotopic niches in three Guadeloupe rivers affected by damming and water catchment

Native fauna of the tropical volcanic part of Guadeloupe is amphidromous: juveniles born in rivers but that grow in the sea need to migrate upstream to colonise their adult habitat in rivers. This migration is affected by any human-made obstacles placed in their way. Moreover, on volcanic tropical islands, streams are the main source of water catchment for the human population. This deeply affects river hydrology and characteristics. Both damming and water catchment potentially affect community diversity and species demography, but they may also alter the trophic ecology of the river fauna. Using stable isotopes and the stable isotope Bayesian ellipses approach in R (SIBER), this study aimed to assess the isotopic niche variability of riverine fauna of three persistent small rivers of Basse-Terre Island (Guadeloupe) affected by damming and water catchment. Using electrofishing, decapods and fishes (gobies) of three rivers were sampled upstream and downstream of dams. Our results demonstrated that the variability of the isotopic niches was extremely high between rivers but varied less between stations of the same river. Our results revealed complex and river-specific effects and a pattern merged with natural variability. Our two hypotheses (i.e., increase of resources upstream of dams and differential responses of trophic guilds to damming and water catchment) were only weakly supported and never in an unambiguous manner. Our study showed that it is necessary to consider the ‘noise’ generated by natural variability to observe and understand changes in the trophic ecology of associated fauna in relation to damming and water catchment