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Soil and river contamination patterns of chlordecone in a tropical volcanic catchment in the French West Indies (Guadeloupe)
2016
Crabit A. | Cattan P. | Colin F. | Voltz M.
The aim of this study was to identify primary flow paths involved in the chlordecone (CLD) river contamination and quantify the CLD fluxes to assess CLD pollution levels and duration according to a typical catchment of the banana cropping area in the French Indies (Guadeloupe): the Pérou Catchment (12 km2) characterized by heavy rainfall (5686 mm year?1). Three sub-catchments (SC1, SC2 and SC3) were studied during the hydrological year 2009–2010: a pedological survey combined with a spatialized hydrochemical approach was conducted. The average soil concentration is higher in the Pérou Catchment (3400 ?g kg?1) than in the entire banana cropping area in Guadeloupe (2100 ?g kg?1). The results showed that CLD stocks in soils vary largely among soil types and farming systems: the weakest stocks are located upstream in SC1 (5 kg ha?1), where a majority of the area is non-cultivated; medium stocks are located in Nitisols downstream in SC3 (9 kg ha?1); and the greatest stocks are observed in SC2 on Andosols (12 kg ha?1) characterized by large farms. The annual water balance and the hydro-chemical analysis revealed that the three sub-catchments exhibited different behaviors. Pérou River contamination was high during low flows, which highlighted that contamination primarily originated from groundwater contributions. The results showed that only a small part of the catchment (SC2), contributing little to the water flow, comprises a major CLD contribution, which is in agreement with the highly contaminated andosol soils observed there. Another significant result considers that at least 50 years would be required to export the totality of the actual CLD soil stocks retained in the topsoil layer. The actual time for soil remediation will however be much longer considering (i) the necessary time for the chlordecone to percolate and be stored in the shallow aquifers and (ii) its travel time to reach the river. (Résumé d'auteur)
Afficher plus [+] Moins [-]Analysis of surface water reveals land pesticide contamination: An application for the determination of chlordecone-polluted areas in Guadeloupe, French West Indies
2020
Rochette, Romain | Bonnal, Vincent | Andrieux, Patrick | Cattan, Philippe
In Guadeloupe, the use between 1972 and 1993 of chlordecone, an organochlorine insecticide, has permanently contaminated the island's soil, thus contaminating the food chain at its very beginning. There is today a strong societal requirement for an improved mapping of the contaminated zones. Given the extent of the areas to be covered, carrying out soil tests on each plot of the territory would be a long and expensive process. In this article, we explore a method of demarcating polluted areas. The approach adopted consists in carrying out, using surface water analyses, a hydrological delimitation that makes it possible to distinguish contaminated watersheds from uncontaminated ones. The selection of sampling points was based on the spatial analysis of the actual and potential contamination data existing at the beginning of the study. The approach was validated by soil analyses, after having compared the contamination data of the watersheds with the soil contamination data of the plots within them. The study thus made it possible to highlight new contaminated areas and also those at risk of contamination and to identify the plots to be targeted as a priority during future analysis campaigns by State services.
Afficher plus [+] Moins [-]Integrated modeling of agricultural scenarios (IMAS) to support pesticide action plans: the case of the Coulonge drinking water catchment area (SW France)
2017
Vernier F. | Leccia-Phelpin O. | Lescot J.M. | Minette S. | Miralles A. | Barberis D. | Scordia C. | Kuentz-Simonet V. | Tonneau J.P.
Non-point source pollution is a cause of major concern within the European Union. This is reflected in increasing public and political focus on a more sustainable use of pesticides, as well as a reduction in diffuse pollution. Climate change will likely to lead to an even more intensive use of pesticides in the future, affecting agriculture in many ways. At the same time, the Water Framework Directive (WFD) and associated EU policies called for a “good” ecological and chemical status to be achieved for water bodies by the end of 2015, currently delayed to 2021–2027 due to a lack of efficiency in policies and timescale of resilience for hydrosystems, especially groundwater systems. Water managers need appropriate and user-friendly tools to design agro-environmental policies. These tools should help them to evaluate the potential impacts of mitigation measures on water resources, more clearly define protected areas, and more efficiently distribute financial incentives to farmers who agree to implement alternative practices. At present, a number of reports point out that water managers do not use appropriate information from monitoring or models to make decisions and set environmental action plans. In this paper, we propose an integrated and collaborative approach to analyzing changes in land use, farming systems, and practices and to assess their effects on agricultural pressure and pesticide transfers to waters. The integrated modeling of agricultural scenario (IMAS) framework draws on a range of data and expert knowledge available within areas where a pesticide action plan can be defined to restore the water quality, French “Grenelle law” catchment areas, French Water Development and Management Plan areas, etc. A so-called “reference scenario” represents the actual soil occupation and pesticide-spraying practices used in both conventional and organic farming. A number of alternative scenarios are then defined in cooperation with stakeholders, including socio-economi
Afficher plus [+] Moins [-]Hydrotelluric and industrial fluorosis survey in the dromedary camel in the south of Morocco
2008
Diacono, Emilie | Faye, Bernard | Bengoumi, Mohammed | Kessabi, Mohamed
Morocco is the first country producer of phosphate in the world with a real potential of contamination of the environment and individuals there living by fluorine either by phosphate deposits (hydrotelluric fluorosis) and phosphate manufacturing plants (industrial fluorosis). This survey was achieved on 86 dromedaries in a region of the Sahara (Boujdour and Laâyoune) characterized by the presence of phosphate. In addition, blood, soil, water and plant samples were collected for the dosage of fluorine that has been achieved by potentiometric method. The mean fluorine content was below 0.47 ppm, 513 ppm and 4.8 ppm in water, soil and plants respectively. The provinces of Boujdour and Laâyoune are unscathed zones opposite the sources of fluorine contamination, as water, vegetation and soil. The mean plasma fluorine concentration was below 0.06 ppm, thus, the camels of these regions seem therefore also free of fluorine chronic intoxication. However the increased values of fluorine levels in the soil, vegetables, and the plasma of camels in the region of Boujdour can let suppose that this area is close to a source of fluorine contamination. Indeed, the province of Boujdour is located unless 200 km of Boukraa where is situated a processing plant of phosphates. Thus, according orientation and the strength of the present dominant winds in the region of Boujdour, we can give out the hypothesis that by winds are brought in the region of Boujdour of the fluorine particles coming from the region of Boukraa. These winds carrying particles of fluorine eliminated by the factory and also by the extraction of soil particles by erosion. This hypothesis can be verified by a survey establishing a gradient of pollution by fluorine cleared by the deposit or the processing plant of the phosphates considering the direction and the strength of the dominant winds in these regions. (Résumé d'auteur)
Afficher plus [+] Moins [-]Plant, water and milk pollution in Kazakhstan
2008
Diacono, Emilie | Faye, Bernard | Meldebekova, Aliya | Konuspayeva, Gaukhar
Since its independence in 1991, Kazakhstan is in a state of "ecological crises", due to the specific place for nuclear test by soviet government for long time, and to the development of irrigation for field cottons linked with decreasing Aral Sea level. In addition the manufacturing of metals and the minerals had some impact on environmental contamination. In the South of Kazakhstan, eight farms were sampled close to probable pollution sources. Samples of camel milk, fodder and water were collected in each farm and analyzed for copper, iron, manganese, zinc, arsenic and lead. The mean content in fodder of Cu, Fe, Mn, Zn, As and Pb was 10.40 ± 2.93, 793.69 ± 630.48, 62.38 ± 20.67, 32.95 ± 27.15, 1.03 ± 0.49 and 4.28 ± 9.60 ppm respectively. In camel milk mean content of these heavy metals was respectively of 0.07 ± 0.04, 1.48 ± 0.53, 0.08 ± 0.03, 5.16 ± 2.17, <0.1, and 0.025 ± 0.02 ppm respectively. No heavy metals were detected in samples of water with the analytical methods used. The relationships between heavy metals in water, forages and milk were not clear. Some information's are lacking. We need to extend sampling at more areas where camels, cows, goat and sheep farms are closed to pollution areas, and analyzed other heavy metals suspected in pollution process.
Afficher plus [+] Moins [-]Characterization of river pollution at the watershed scale
2016
Lesueur Jannoyer M. | Mottes C. | Clostre F. | Carles C. | Guene M. | Plet J. | Della Rossa P. | Bazizi A. | Cattan P.
The challenge of knowledge representation to better understand environmental pollution
2016
Cattan P. | Tonneau J.P. | Charlier J.B. | Ducreux L. | Voltz M. | Bricquet J.P. | Andrieux P. | Arnaud L. | Lesueur Jannoyer M.
Crisis management of chronic pollution: contaminated soil and human health
2016
Lesueur Jannoyer M. (ed.) | Cattan P. (ed.) | Woignier T. (ed.) | Clostre F. (ed.)
Crisis Management of Chronic Pollution: Contaminated Soil and Human Health deals with a long term pollution problem, generated by the former use of organochlorine pesticides. Through a case study of the chlordecone pollution in the French West Indies, the authors illustrate a global and systemic mobilization of research institutions and public services. This "management model", together with its major results, the approach and lessons to be learned, could be useful to other situations. This book gathers all the works that have been carried out over the last ten years or more and links them to decision makers' actions and stakeholders' expectations. This reference fills a gap in the literature on chronic pollution. (Résumé d'auteur)
Afficher plus [+] Moins [-]Research of some physicochemical and biological pollution indicators in four fisheries of the northern part of Cameroon
2013
Maïworé J. | Tatsadjieu N.L. | Montet D. | Mbofung C.M.
The bacteriological and physicochemical characteristics of water and sediment collected in four fisheries situated in the north of Cameroon were evaluated. In these locations, all the analysed parameters (temperature, pH, salinity, conductivity, turbidity, suspended matter, organic matter, phosphates, sulphates, nitrates, chloride, calcium, magnesium, iron and nitrogen) were the highest, except for chlorides. Total mesophile aerobic flora varied between 1.4±0.50×105 in Tibati and 5.57±0.50×106 CFU/mL in Lagdo. Salmonella concentration was comprised between 66.66±1.62 in Tibati and 274±3.16 CFU/mL in Yagoua. There was about 10±0.50 CFU/mL Vibrio in Lagdo and 342.27±5.53 CFU/mL in Maga. Staphylococcus concentration was between 1.4±0.55×103 CFU/mL in Tibati and 4.44±0.9×104 in Maga. Clostridia were comprised between 0.33±0.00 in Tibati and 226.66±4.29 CFU/mL in Maga while Pseudomonas concentration was comprise between 16.26±0.70 in Tibati and 326.66±6.00 CFU/mL in Lagdo. Faecal Streptococcus varied between 0.33±0.00 in Tibati and 238.66±8.15 CFU/mL in Yagoua. The total mesophile aerobic flora was significantly high (P<0,005) in Lagdo while Clostridium, faecal streptococcus, and Streptococcus concentration were significantly high in Maga, Yagoua and Lagdo. Lake's sediments in Maga were the most infected. The different analysis revealed that the fisheries were relatively polluted. Some of the bacteria counted like Pseudomonas and Vibrio might be pathogenic for fishes. (Résumé d'auteur)
Afficher plus [+] Moins [-]Linking current river pollution to historical pesticide use: Insights for territorial management?
2017
Della Rossa P. | Jannoyer M. | Mottes C. | Plet J. | Bazizi A. | Arnaud L. | Jestin A. | Woignier T. | Gaude J.M. | Cattan P.
Persistent organic pollutants like organochlorine pesticides continue to contaminate large areas worldwide raising questions concerning their management. We designed and tested a method to link soil and water pollution in the watershed of the Galion River in Martinique. We first estimated the risk of soil contamination by chlordecone by referring to past use of land for banana cultivation and took 27 soil samples. We then sampled surface waters at 39 points and groundwater at 16 points. We tested three hypotheses linked to the source of chlordecone pollution at the watershed scale: (i) soils close to the river, (ii) soils close to the sampling point, (iii) throughout the sub-watershed generated at the sampling point. Graphical and statistical analysis showed that contamination of the river increased when it passed through an area with contaminated plots and decreased when it passed through area not contaminated by chlordecone. Modeling showed that the entire surface area of the watershed contributed to river pollution, suggesting that the river was mainly being contaminated by the aquifers and groundwater flows. Our method proved to be a reliable way to identify areas polluted by chlordecone at the watershed scale and should help stakeholders focus their management actions on both hot spots and the whole watershed. (Résumé d'auteur)
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