Éditeur(s) : Université des Antilles et de la Guyane CEREGMIA : Centre d'Etudes et de Recherche en Economie, Gestion et Modélisation Informatique Appliquée
Extrait de : "The changing world of coastal, island and tropical tourism" : conférence internationale, du 27 au 29 janvier 2011. Université des Antilles et de la Guyane
Description : The globalization process, accelerating in the last 20 years, has raised important developmental stakes : on the one hand, economic questions with the multiplication of exchanges and its concentration in certain regions of the world; on the other hand globalization has also raised important social issues, with the acceleration of demographic flux and the whole question of "inclusion" associated with this; the issues are also environmental, through increased needs and resource limitations. Tourism represents the ideal vector of this globalization and the stakes it represents. By focusing on international tourism in a country in the South, this article seeks to better understand the stakes involved in developing international tourism resources, by seeking an answer to the question : In what ways can ecotourism constitute a real strategy for economic development, poverty alleviation, and contribute to economic growth and the protection of natural resources ? We will be examining this question in the context the Ranomafana National Park in Madagascar.

Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification
Provenance : Université des Antilles et de la Guyane. Service commun de la documentation
Permalien : http://www.manioc.org/fichiers/HASH29f953af13018e4196aff5
HASH29f953af13018e4196aff5

Éditeur(s) : Université des Antilles et de la Guyane CEREGMIA : Centre d'études et de recherche en économie, gestion et modélisation informatique appliquée Université des Antilles et de la Guyane CEREGMIA : Centre d'études et de recherche en économie, gestion et modélisation informatique appliquée
Résumé : The globalization process, accelerating in the last 20 years, has raised important developmental stakes : on the one hand, economic questions with the multiplication of exchanges and its concentration in certain regions of the world; on the other hand globalization has also raised important social issues, with the acceleration of demographic flux and the whole question of "inclusion" associated with this; the issues are also environmental, through increased needs and resource limitations. Tourism represents the ideal vector of this globalization and the stakes it represents. By focusing on international tourism in a country in the South, this article seeks to better understand the stakes involved in developing international tourism resources, by seeking an answer to the question : In what ways can ecotourism constitute a real strategy for economic development, poverty alleviation, and contribute to economic growth and the protection of natural resources ? We will be examining this question in the context the Ranomafana National Park in Madagascar.

Droits : Document protégé par le droit d'auteur
fichiers:HASH29f953af13018e4196aff5

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
CONTEXT: Chlordecone, an environmentally persistent organochlorine insecticide used intensively in banana culture in the French West Indies until 1993, has permanently polluted soils and contaminated foodstuffs. Consumption of contaminated food is the main source of exposure nowadays. We sought to identify main contributors to blood chlordecone concentration (BCC) and to validate an exposure indicator based on food intakes. MATERIAL AND METHODS: We used a food frequency questionnaire (FFQ) completed by a sample of 194 pregnant women to estimate their dietary exposure to chlordecone and compared it to blood levels. In a first approach, chlordecone daily intake was estimated as the product of daily eaten quantity of 214 foodstuffs, multiplied by their chlordecone content, and summed over all items. We then predicted individual blood chlordecone concentration with empirical weight regression models based on frequency of food consumption, and without contamination data. RESULTS: Among the 191 subjects who had BCC determination, 146 (76%) had detectable values and mean BCC was 0.86 ng/mL (range < LOD-13.2). Mean per capita dietary intake of chlordecone was estimated at 3.3 microg/day (range: 0.1-22.2). Blood chlordecone levels were significantly correlated with food exposure predicted from the empirical weight models (r=0.47, p<0.0001) and, to a lesser extent, with chlordecone intake estimated from food consumption and food contamination data (r=0.20, p=0.007). Main contributors to chlordecone exposure included seafood, root vegetables, and Cucurbitaceous. CONCLUSION: These results show that the Timoun FFQ provides valid estimates of chlordecone exposure. Estimates from empirical weight models correlated better with blood levels of chlordecone than did estimates from the dietary intake assessment.
ISSN: 0013-9351

inserm-00517109
http://www.hal.inserm.fr/inserm-00517109
http://www.hal.inserm.fr/inserm-00517109/document
http://www.hal.inserm.fr/inserm-00517109/file/Pesticide_exposureofpregnantwomeninGuadeloupe.pdf
DOI : 10.1016/j.envres.2009.10.015

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
29 inorganic compounds (Al, As, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cu, Fe, Gd, K, Mg, Mn, Mo, Na, Nd, Ni, Pb, Sb, Se, Sr, Ti, U, V and Zn) were measured in the tap water of 484 representative homes of children aged 6 months to 6 years in metropolitan France in 2008-2009. Parents were asked whether their children consumed tap water. Sampling design and sampling weights were taken into account to estimate element concentrations in tap water supplied to the 3,581,991 homes of 4,923,058 children aged 6 months to 6 years. Median and 95th percentiles of concentrations in tap water were in mu g/L: Al: <10, 483, As: 02, 2.1; B: <100, 100; Ba: 30.7, 149.4; Ca: 85,000, 121,700; Cd: <0.5, <0.5; Ce: <0.5, <0.5; Co: <0.5, 0.8; Cr: <5, <5; Cu: 70, 720; K: 2210, 6740; Fe: <20, 46; Mn: <5, <5; Mo: <0.5,1.5; Na: 14,500, 66,800; Ni: <2,10.2; Mg: 6500,21,200; Pb: <1, 5.4; Sb: <0.5, <0.5; Se: <1, 6.7; Sr: 256.9, 1004; TI: <0.5, <0.5; U: <0.5, 2.4; V: <1, 1; Zn; 53, 208. Of the 2,977,123 young children drinking tap water in France, some were drinking water having concentrations above the 2011 World Health Organization drinking water quality guidelines: respectively 498 (CI 95%: 0-1484) over 700 mu g/L of Ba; 121,581 (CI 95%: 7091-236,070) over 50 mg/L of Na; 2044 (CI 95%: 0-6132) over 70 mu g/L of Ni, and 78,466 (17,171-139,761) over 10 mu g/L of Pb. Since it is representative, this tap water contamination data can be used for integrated exposure assessment, in conjunction with diet and environmental (dust and soil) exposure data. (C) 2016 Elsevier Ltd. All rights reserved.
ISSN: 0160-4120

hal-01390976
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01390976
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01390976/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01390976/file/Le%20Bot%202016%20EI%20revision1%20.pdf
DOI : 10.1016/j.envint.2016.06.009

Éditeur(s) : Copernicus Gesellschaft Mbh
Résumé : The distributions of the bio-essential trace element dissolved cobalt (DCo) and the apparent particulate Co (PCo) are presented along the GEOTRACES-A02 deep section from 64(o) N to 50(o) S in the western Atlantic Ocean (longest section of international GEOTRACES marine environment program). PCo was determined as the difference between total cobalt (TCo, unfiltered samples) and DCo. DCo concentrations ranged from 14.7 pM to 94.3 pM, and PCo concentrations from undetectable values to 18.8 pM. The lowest DCo concentrations were observed in the subtropical domains, and the highest in the low-oxygenated Atlantic Central Waters (ACW), which appears to be the major reservoir of DCo in the western Atlantic. In the Antarctic Bottom Waters, the enrichment in DCo with aging of the water mass can be related to suspension and redissolution of bottom sediments a well as diffusion of DCo from abyssal sediments. Mixing and dilution of deep water masses, rather than scavenging of DCo onto settling particles, generated the meridional decrease of DCo along the southward large-scale circulation in the deep western Atlantic. Furthermore, the apparent scavenged profile of DCo observed in the deep waters likely resulted from the persistence of relatively high concentrations in intermediate waters and low DCo concentrations in underlaying bottom waters. We suggest that the 2010 Icelandic volcanic eruption could have been a source of DCo that could have been transported into the core of the Northeast Atlantic Deep Waters. At intermediate depths, the high concentrations of DCo recorded in the ACW linearly correlated with the apparent utilization of oxygen (AOU), indicating that remineralization of DCo could be significant (representing up to 37% of the DCo present). Furthermore, the preferential remineralization of phosphate (P) compared to Co in these low-oxygenated waters suggests a decoupling between the deep cycles of P and Co. The vertical diffusion of DCo from the ACW appears to be a significant source of DCo into the surface waters of the equatorial domain. Summarizing, the dilution due to mixing processes rather than scavenging of DCo and the above-mentioned remineralization could be the two major pathways controlling the cycling of DCo into the intermediate and deep western Atlantic.
Biogeosciences (1726-4170) (Copernicus Gesellschaft Mbh), 2014 , Vol. 11 , N. 6 , P. 1561-1580

Droits : Author(s) 2014. CC Attribution 3.0 License.
http://archimer.ifremer.fr/doc/00241/35223/33727.pdf
DOI:10.5194/bg-11-1561-2014
http://archimer.ifremer.fr/doc/00241/35223/

Éditeur(s) : Université de La Rochelle
Résumé : Shrimp aquaculture in New Caledonia is a developing industry, exclusively based on the species Litopenaeus stylirostris. However, it is subject to mortalities during grow out as observed all over the world. Since 1993, shrimp reared during the cold period are affected by a disease named "syndrome 93". As a consequence, the whole industry has become seasonal and produces essentially during the warm season. The climatic conditions during the periods of transition between the two main seasons could be responsible for an environmental stress and the origin reason for mortality outbreaks. Stocking density is the main risk factor. It increases the probability of the appearance and development of the epizooty in the pond. The "Summer Syndrome", a septicemic vibriosis caused by Vibrio nigripulchritudo, was identified for the first time in December 1997 in an intensive shrimp farm (DF). It has become enzootic ever since and is expressed after 50d of rearing. Since 2003, two others farms located near DF have developed the disease. As a consequence, the summer syndrome is considered to be a potential threat for all the industry. Between 1991 and 2005, the increase of feed input and nitrogen levels in feed has led to a significant increase in the growth rate over the years in the farms affected by the disease. In consequence, an early eutrophication of the water is observed, which is concomitant with the beginning of the mortality outbreaks. An early eutrophication and the virulence level of the pathogen are considered as the main risk factors of the disease. Factors may act synergistically to explain the summer syndrome. As part of a multidisciplinary approach (pathology – physiology – environment), two high-frequency surveys were carried out to analyse the pond ecosystem. Since the feed quantity increases with the biomass of shrimp, the eutrophication level of the pond ecosystem will also tend to increase with the duration of rearing. During the first part of the rearing, the abundance of each picoplankton type is exceptionally high and picophytoplankton dominated the autotrophic compartment. The nanophytoplankton dominated the second part of the rearing and was more unstable. The shift from pico to nanophytoplankton could be considered as an environmental stress and was observed in relation to the beginning of the mortalities, whatever the disease. Shift intensity could play a role by inducing directly or indirectly a stress for shrimp and/or a growth and/or virulence factors of the pathogen. Results from sediment studies show that mortality was best characterized by TAN concentration in pore water and even more when the TAN concentration was high. TAN and pH are potential stress factors for shrimp reared in ponds affected by these diseases.
L'aquaculture mondiale de crevettes est un secteur à très forte croissance. Toutefois, les problèmes liés aux maladies dans les élevages ne cessent d'augmenter depuis 1980. Au cours du développement de la filière de Nouvelle-Calédonie, deux épisodes saisonniers de mortalités associées à la présence de Vibrio pathogènes sont apparus et ont fortement perturbé les techniques et les schémas de production. Les premières mortalités hivernales, décrites sous le nom de « syndrome 93 » ont été observées en mai 1993. Elles ont affecté depuis tous les élevages de saison froide de toutes les fermes de production. Les conditions climatiques pendant les périodes de transitions entre les deux principales saisons caractérisant le climat de la Nouvelle-Calédonie, seraient responsables d'un stress environnemental à l'origine du déclenchement du syndrome 93. La densité initiale d'ensemencement, apparaît comme le principal facteur de risque, augmentant la probabilité d'apparition de la maladie et l'ampleur de ses effets. Le « syndrome d'été » a été identifié pour la première fois en 1997 dans une ferme pratiquant une production intensive. Il s'est déclaré depuis 2003 dans deux autres fermes géographiquement proches. Les mortalités apparaissent 58 jours en moyenne après l'ensemencement des post-larves dans les bassins. La recherche d'une croissance maximale des animaux a induit, avec les années, une intensification progressive du système caractérisée par une augmentation de la quantité d'aliment distribuée. L'examen des données historiques fait apparaître une eutrophisation du milieu de plus en plus précoce concomitante au déclenchement des mortalités. En l'état actuel de nos connaissances, cette évolution précoce de l'écosystème en présence de façon récurrente de la souche hautement pathogène du Vibrio incriminé et à une période où la fréquence des mues des crevettes est élevée, constitue le principal facteur de risque de la maladie. Avec l'apport croissant en aliment, la colonne d'eau évolue vers une autotrophie croissante alors que le sédiment devient de plus en plus hétérotrophe au fur et à mesure que l'élevage progresse. Au cours du processus d'eutrophisation, le compartiment autotrophe montre une succession de deux assemblages. Le picophytoplancton domine sur la première partie de l'élevage et laisse place à du nanophytoplancton en seconde partie. Cette phase de transition, concomitante à l'apparition des mortalités quel que soit le syndrome, caractérise un stress environnemental dont l'intensité pourrait favoriser ou non le déclenchement des mortalités. Les suivis de différents indicateurs dans les sédiments - pH, potentiel d'oxydoréduction et concentration en ammoniaque dans l'eau interstitielle – indiquent dans les bassins déclarant les épizooties des conditions qui ont été définies expérimentalement comme potentiellement plus stressantes pour les animaux.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2007/these-2643.pdf
http://archimer.ifremer.fr/doc/00000/2643/

Éditeur(s) : Montpellier 1
Résumé : Understanding bioaccumulation mechanisms of persistent organic pollutants (POPs) is a major issue for environmental risk assessment. In this work, polychlorinated biphenyls (PCBs), a model contaminant family, has been studied in the European hake (Merluccius merluccius), a high trophic level species from the Gulf of Lions. High concentrations of PCBs were measured in hake from this area compared to those encountered in the population of the Bay of Biscay. PCB biomagnification was highlighted along its food web from marine phytoplankton, suggesting a strong influence of diet on contamination levels. The role of other biological processes was also apprehended in order to understand the high variability of observed levels. Thus, growth, sex, and also the degree of sexual maturity appear as major factors explaining the measured concentrations in fish. A PCB bioaccumulation model in the hake, based on the Dynamic Energy Budget theory (DEB), was developed. This approach is based on a bioenergetic model, reproducing the main physiological functions of an organism (feeding, growth and reproduction), coupled with a kinetic model of contaminants. The growth and evolution of contamination levels of several PCB congeners during the life of male and female hakes is satisfactorily simulated, both in the Gulf of Lions and in the Bay of Biscay, validating the processes taken into account. This combined modelling approach appears well adapted to study the fate of contaminants in fish, and paves the way for a realistic understanding of their effects on major biological functions of fish.
La compréhension des mécanismes de bioaccumulation des contaminants organiques persistants (POP) est un enjeu majeur pour l'évaluation des risques environnementaux. Lors de ce travail, le devenir d'une famille de contaminants modèles, les polychlorobiphényles (PCB), a été étudié chez une espèce de rang trophique élevé du golfe du Lion, le merlu Européen (Merluccius merluccius). Des concentrations élevées en PCB ont été mesurées dans les merlus de ce secteur en comparaison à celles rencontrées dans la population du golfe de Gascogne. La mise en évidence d'une bioamplification des PCB le long de son réseau trophique, depuis le phytoplancton marin, suggère une influence importante de l'alimentation sur les niveaux de contamination. Le rôle d'autres processus biologiques a également été appréhendé afin de comprendre la forte variabilité des niveaux observés. Ainsi, la croissance, le sexe, mais également le degré de maturité sexuel apparaissent comme des facteurs explicatifs majeurs des concentrations en PCB mesurées dans les poissons. Un modèle de bioaccumulation des PCB chez le merlu, basé sur la théorie de Budget d'Energie Dynamique (DEB), a été développé. Il s'agit d'une approche basée sur le couplage d'un modèle bioénergétique, reproduisant les principales fonctions physiologiques de l'organisme (nutrition, croissance et reproduction), avec un modèle de cinétique des contaminants. La croissance et l'évolution des niveaux de contamination de plusieurs congénères de PCB au cours de la vie des merlus mâles et femelles est simulée de manière satisfaisante, tant dans le golfe de Gascogne que dans le golfe du Lion, validant ainsi les processus pris en compte. Cette approche combinée de modélisation apparaît tout à fait adaptée à l'étude du devenir des contaminants chez les poissons, et ouvre la voie à une compréhension réaliste de leurs effets sur les grandes fonctions biologiques de ces organismes.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2008/these-6490.pdf
http://archimer.ifremer.fr/doc/00000/6490/

Éditeur(s) : Yale University
Résumé : Sea-surface temperature images of the coastal upwelling regions off Northwest Africa show that the core of upwelling is sometimes located far from the coast. This has been documented in three regions that share a common feature, namely a wide and shallow continental shelf. This upwelling feature plays a key role in the ecology of the Canary Current System. It creates an innerfront which provides retention for biological material, e.g. fish eggs and larvae, in the highly productive nearshore environment. An analytical model has been developed based on a two dimensional extension of Ekman's solution. The linear and steady response of a homogeneous ocean forced by an upwelling-favorable wind provides a mechanism for the upwelling separation from the coast. The merging of the surface and bottom Ekman layers induces a very weak cross-shore circulation and a "kinematic barrier" for the Ekman transport divergence. In the case of an alongshore wind, the barrier is located near the isobath h ≈ 0.4D, where D is the thickness of Ekman layers. This yields an upwelling cell which is essentially concentrated in the region 0.5D < h < 1.25D, with upwelling occurring preferentially near the isobath h ≈ 0.6D. It turns out that the cross-shore width of upwelling scales with D/S, the ratio of Ekman depth to bottom topographic slope. The application of this solution to real bathymetric profiles rationalizes, not only the offshore upwelling observations in Northwest Africa, but also the influence of topography on the cross-shelf structure of a wind-driven coastal upwelling. The model also quantifies the effect of the cross-shore wind component showing how it drives the nearshore pressure gradient adjustment and how it affects the upwelling. A linear numerical experiment reproduces the theoretical steady solution, thereby allowing investigation of the transient regime. Relaxation of the hypothesis in the numerical model validates the linear assumption of the theory and then allows investigation of the sensitivity to friction parameterizations and the influence of stratification. The latter leads to an "oscillation" of the upwelling cell with seaward migration driven by outcropping and homogeneization of the water column, and, coastal incursion driven by a "boundary layers splitting" process caused by shoreward advection of the isopycnal dome and stratification of the inner shelf.
Journal of Marine Research (Yale University), 2008-09 , Vol. 66 , N. 5 , P. 589-616

Droits : 2008 Yale University
http://archimer.ifremer.fr/doc/2008/publication-6334.pdf
DOI:10.1357/002224008787536790
http://archimer.ifremer.fr/doc/00000/6334/

Éditeur(s) : Adac-cryptogamie
Résumé : Very few attempts have been made in order to investigate the role of nutrients on cellular growth and toxin production in dinoflagellates associated with DSP (Diarrhetic Shellfish Poison). Some preliminary results are presented here, aiming at a better knowledge of inorganic nitrogen and organic phosphorus effects upon division rate and toxin content of Prorocentrum lima (PL2V spanish strain). Nitrogen have a positive effect on growth rate, up to a threshold value of 880muM.l-1. Above this threshold the rate decreases. There is no effect on toxin content since okadaic acid and DTX1 cell contents remain low (4.8 +/- 0.5 pg.cell.-1) and steady. Phosphorus effect upon division rate follows a non-linear relationship, whereas cellular toxic content is inversely proportional to growth rate.
Peu d'études ont été réalisées sur l'influence des nutriments sur la croissance et la toxicité de dinoflagellés producteurs de poisons diarrhéiques (Diarrhetic Shellfish Poison = DSP). Des résultats préliminaires sont présentés ici en ce qui concerne l'effef de concentrations croissantes d'azote inorganique et de phosphore organique sur le taux de division et la production toxinique de Prorocentrum lima (souche espagnole PL2V). L'azote a une influence positive sur la croissance de cette microalgue jusqu'à une valeur seuil de 880 μM.l#-1. Au-delà de ce seuil, le taux de division diminue. Par contre, l'effet sur la toxicité n'est pas significatif, les concentrations en acide okadaïque et DTXI restant relativement faibles (4.8 ± 0.5 pg.cell.· l ) et stables. Le phosphore agit intégralement sur le taux de division et il y a une relation inverse entre ce dernier et le contenu toxinique cellulaire.
Cryptogamie Algologie (0181-1568) (Adac-cryptogamie), 1992-08 , Vol. 13 , N. 3 , P. 187-195

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00133/24469/22483.pdf
http://archimer.ifremer.fr/doc/00133/24469/

Éditeur(s) : Pergamon-elsevier Science Ltd
Résumé : Sites of monomethylmercury (MMHg) production in Amazonian regions have been identified in hydraulic reservoirs, lake sediments and wetlands, but tailings ponds have not yet received sufficient attention for this purpose. This work evidenced high MMHg production within the water column and the interstitial water of two tailings ponds of French Guiana Au mines located; (i) in a small scale exploitation (Combat) where Hg was used for Au amalgamation, and (ii) in an industrial on-going Au mine (Yaoni) processing without Hg. The (MMHg)(D) maximum (2.5 ng L-1) occurred in the oxic water column above the sediment-water interface (SWI) of the most recent tailings pond (Combat), where the substrate was fresh, the redox transition was sharp and the pool of total Hg was large. In the Yaoni pond, the (MMHg)(D) maximum concentration (1.4 ng L-1) was located at the SWI where suboxic conditions prevailed. Using the (MMHg)(D) concentration as a proxy for Hg methylation rates, the present results show that Hg methylation may occur in various redox conditions in tailings ponds, and are favored in areas where the organic matter regeneration is more active. A 3-month long laboratory experiment was performed in oxic and anoxic boxes filled with high turbidity waters from the Combat Au mine to simulate tailings ponds. Slaked lime was added in an experimental set (2 mg L-1)and appeared to be very efficient for the reduction of suspended particulate matter (SPM) to environmentally acceptable concentrations. However, at the end of the experiment, large (MMHg)(D) concentrations were monitored under treated anoxic conditions with the (MMHg)(D) maximum located at the SWI above the Fe-reducing zones. No (MMHg)(D) was detected in oxic experiments. The use of slaked lime for SPM decantation appears to be an efficient and non-onerous process for Au miners to avoid Hg methylation in tailings ponds when it is combined with rapid drainage of the mine waters. A subsequent human intervention is however necessary for the recovery of soil structure through the cover of dried ponds with organic rich materials and reforestation to avoid the stagnation of rain waters and the occurrence of anoxia. (C) 2010 Elsevier Ltd. All rights reserved.
Applied Geochemistry (0883-2927) (Pergamon-elsevier Science Ltd), 2011-02 , Vol. 26 , N. 2 , P. 222-229

Droits : 2010 Elsevier Ltd All rights reserved.
http://archimer.ifremer.fr/doc/00030/14117/12133.pdf
DOI:10.1016/j.apgeochem.2010.11.022
http://archimer.ifremer.fr/doc/00030/14117/

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Ce numéro de la Revue Etudes Caribéennes consacré au tourisme vise à poser les bases d’une réflexion sur le fonctionnement des lieux touristiques, les programmes d’aménagement touristique et les différents enjeux pour les territoires. Lieu ouvert ou lieu fermé, flux concentré ou flux diffus, la nature du lieu touristique, avec ses pratiques, classiques ou originales, oriente les types d’impacts potentiels. Les choix opérés en matière d’aménagement touristique sont donc primordiaux : dans quelles conditions opte-t-on pour un tourisme balnéaire classique, massif, ou pour une approche touristique alternative ? Ces différentes déclinaisons sont-elles attachées à des territoires spécifiques ? Faut-il opposer ces deux approches ou les considérer complémentaires dans leurs environnements respectifs, peuvent-elles partager un même espace ? L’objectif de ce numéro thématique est de réunir des approches diverses et renouvelées qui développent des analyses sous l’angle de l’économie, de l’aménagement du territoire, de la sociologie, de la géographie… Les articles pourront proposer une réflexion théorique ou privilégier des études de cas, traitant des relations tourisme de masse – tourisme alternatif ou s’attachant à illustrer l’une de ces deux aspects. Les terrains privilégiés ne seront pas exclusivement caribéens et américains, ils pourront relever de n’importe quelle région du monde et illustrer des situations présentes et/ou passées. Les thématiques privilégiées seront : 1. Les concepts de tourisme de masse et de tourisme alternatif (identification, caractéristiques, logiques spatiales, enjeux économiques, sociaux, environnementaux). 2. Les lieux du tourisme masse (stations balnéaires, villes historiques, formes spécifiques d’aménagement des lieux et les types de structures d’accueil) 3. Alter-tourismes et renouvellement des pratiques touristiques (écotourisme, tourisme communautaire, agrotourisme …) 4. L’aménagement des lieux touristiques et les modalités de gestion des environnements protégés (conservation, protection et pratiques touristiques et récréatives) 5. Les enjeux économiques, sociaux, environnementaux autour de différents types de lieux touristiques. This issue of the Revue Etudes Caribéennes, devoted to tourism, aims to lay the foundations of a reflection on the functioning tourist places, their development programs and the different challenges presented to them. Exposed/Open or closed location, concentrated or diffused flows, the nature of these tourist places with their traditional or original customs, orientate different types of potential impacts. The choices made in tourism development are essential: in which conditions should be opted for the traditional seaside tourism, or for mass tourism, or for alternative tourism? Are certain properties linked to specific territories? Should we oppose these two approaches or consider them as complementary in their environments and can they share the same place? The objective of this thematic issue is to call for various and renewed approaches which develop analysis in terms of the economy, regional planning, sociology, geography etc. Articles may propose a theoretical reflection or focus on case studies, dealing with the relations of mass tourism, alternative tourism, or to illustrate one of these two aspects. Priorities fields will not exclusively be Caribbean and American but can come from any part of the world and can illustrate post and/or present situations. The prioritized analysis will include: 1. The concepts of mass tourism and alternative tourism (identification, characteristics, spatial logics, and economic, social and environmental issues). 2. Places of mass tourism (resorts, historic cities, specific forms of site layout and reception facilities) 3. Alter-tourism and the renewal of tourism practices (ecotourism, community tourism, agrotourism) 4. The development of tourist spots and of management methods concerning protected environments (conservation, protection, tourism practices and recreational practices) 5. Economic, social, and environmental issues surrounding different types of tourist places. Este número de la Revista Estudios Caribeños consagrado al turismo apunta a poner las bases de una reflexión sobre el funcionamiento de los lugares turísticos, los programas de ordenación turística y las diferentes apuestas para los territorios. Lugar abierto o cerrado, flujos concentrados o flujos difusos, la naturaleza del lugar turístico, con sus prácticas, clásicas u originales, orienta los tipos de impactos potenciales. Las elecciones operadas en materia de ordenación turística son primordiales: ¿en qué condiciones se opta por un turismo balneario clásico, masivo, o por un enfoque turístico alternativo? ¿Estas diferentes declinaciones están relacionadas a territorios específicos? ¿Se debe oponer estos dos enfoques o considerarlos complementarios en sus ambientes respectivos, pueden compartir el mismo espacio? El objetivo de este número temático es de reunir los diversos y renovados enfoques que desarrollan los análisis sobre el ángulo de la economía, la ordenación del territorio, la sociología, la geografía… Los artículos podrán proponer una reflexión teórica o privilegiar los estudios prácticos, tratando las relaciones turismo de masa-turismo alternativo o dirigirse a ilustrar uno de estos dos aspectos. Los terrenos privilegiados no serán exclusivamente caribeños y americanos, podrán hacer frente a cualquier región del mundo e ilustrar situaciones presentes y/o pasadas. Los temas privilegiados serán: 1. Los conceptos de turismo de masa y de turismo alternativo (identificación, características, lógicas espaciales, apuestas económicas, sociales, ambientales). 2. Los lugares de turismo de masa (estaciones balnearias, ciudades históricas, formas específicas de ordenación de lugares y de tipos de estructuras de recepción). 3. Alter-turismos y renovación de las prácticas turísticas (ecoturismo, turismo comunitario, agroturismo...). 4. La ordenación de lugares turísticos y las modalidades de gestión de los ambientes protegidos (conservación, protección y prácticas turísticas y recreativas). 5. Las apuestas económicas, sociales, ambientales alrededor de diferentes tipos de lugares turísticos.

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.7521
http://journals.openedition.org/etudescaribeennes/7521

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Le bassin du fleuve Sixaola est un bassin transfrontalier partagé entre le Costa Rica et le Panama. Localisé sur la façade caraïbe de l’isthme centraméricain, il est depuis une vingtaine d’années considérées par les organismes de coopération et les organisations non gouvernementales comme un espace privilégié pour la coopération en matière environnementale. Ce bassin concentre en effet d’importantes richesses naturelles et culturelles propres à cette façade caraïbe. Dans le même temps, on y constate une importante vulnérabilité sociale et des dégradations environnementales croissantes, d’autant plus qu’on trouve autour de ce bassin des activités productives polluantes (monocultures, tourisme, etc.), ainsi que les villages les plus pauvres des deux pays.Cet article cherche à analyser comment, à côté des mécanismes d’intégration et des initiatives appuyées par les États, cet espace connaît aussi de nombreux projets et programmes de coopération menés par des organismes internationaux et des organisations non gouvernementales (ONG). Ces projets visent principalement à accroître la coopération transfrontalière pour la conservation et la gestion environnementale.En revanche, leur rôle est de plus en plus remis en cause par des acteurs locaux qui affirment que ces organismes « transnationaux » déplacent les États et imposent des projets qui ne prennent pas en compte les réalités et les besoins locaux tout en développant des discours « hégémoniques » sur la gestion intégrée des bassins transfrontaliers, le changement climatique, entre autres.
The Sixaola River basin is shared by Costa Rica and Panama. On the Caribbean side of the Central American Isthmus, it has been considered by cooperation organisms and non-governmental organizations as a privileged space for environmental cooperation for the past 20 years. This basin in fact concentrates an important amount of natural and cultural heritage that is endemic to this side of the Caribbean. At the same time, one can observe increasing social vulnerability and environmental degradation related to the presence of the poorest communities of both Panama and Costa Rica within the basin, and to polluting activities (monoculture, tourism, etc.) carried out around it.This article analyzes how this space is the locus of State integration mechanisms and other initiatives, at the same time that it harbors international organism and non-governmental cooperation programs. These latter projects claim to increase trans-border cooperation for conservation and environmental management.But their role is increasingly being contested by local stakeholders, who more and more claim that these “transnational” organisms displace States and impose projects that do not take into account local realities and needs, while developing “hegemonic” discourses on integrated management of trans-border basins and climate change, among other issues.
Amérique centrale
Costa Rica
Panama

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.5747
http://journals.openedition.org/etudescaribeennes/5747

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
BACKGROUND: The insecticide chlordecone was extensively used in the French West Indies to control banana root borer. Its persistence in soils has led to the widespread pollution of the environment, and human beings are still exposed to this chemical. Chlordecone has been shown to impair neurological and behavioural functions in rodents when exposed gestationally or neonatally. OBJECTIVES: The aim of the study was to evaluate the impact of prenatal and postnatal exposure to chlordecone on the cognitive, visual, and motor development of 7-month-old infants from Guadeloupe. METHODS: Infants were tested at 7 months (n=153). Visual recognition memory and processing speed were assessed with the Fagan Tests of Infant Intelligence (FTII), visual acuity with the Teller Acuity Card, and fine motor development with the Brunet-Lezine. Samples of cord blood and breast milk at 3 months (n=88) were analyzed for chlordecone concentrations. Postnatal exposure was determined through breast feeding and frequency of contaminated food consumption by the infants. RESULTS: Cord chlordecone concentrations in tertiles were associated with reduced novelty preference on the FTII in the highly exposed group (β=-0.19, p=0.02). Postnatal exposure through contaminated food consumption was marginally related to reduced novelty preference (β=-0.14, p=0.07), and longer processing speed (β=0.16, p=0.07). Detectable levels of chlordecone in cord blood were associated with higher risk of obtaining low scores on the fine motor development scale (OR=1.25, p<0.01). CONCLUSION: These results suggest that pre- and postnatal low chronic exposure to chlordecone is associated with negative effects on cognitive and motor development during infancy.
ISSN: 0013-9351

hal-00875939
https://hal.archives-ouvertes.fr/hal-00875939
DOI : 10.1016/j.envres.2012.07.006
PUBMED : 22910562

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
Are bisphenol A (BPA) and BPA analogs (BPA-A) safe for male human reproductive function? The endocrine function of human testes explants [assessed by measuring testosterone and insulin-like factor 3 (INSL3)] was impacted by exposure of the human adult testis explants to BPA/BPA-A. The few epidemiologic studies performed suggest that bisphenols have potential endocrine disruptive properties, but they did not identify clear and direct patterns of endocrine disruption. Adult human testis explants in culture were exposed to BPA and the analogs bisphenol F (BPF), bisphenol S (BPS), bisphenol E (BPE), bisphenol B (BPB) and bisphenol A diglycidyl ether (BADGE) at 10(-9)-10(-5) M for 24 or 48 h. Human adult testes were obtained from prostate cancer patients who had no hormone therapy, or from multiorgan donors. After ex vivo exposure to the investigated bisphenols, the measured outcomes were related to histopathology (gross morphology and germ cell viability determined by anti-caspase three immunohistochemistry), and the levels of testosterone, INSL3 and inhibin B were measured using immunoassays. The levels of mRNA encoding key enzymes of bisphenol biotransformation were investigated by quantitative PCR: UGT2B15 UDP (glucuronosyltransferase two family, polypeptide B15), GUSB (glucuronidase beta), SULT1A1 and 3 (sulfotransferase family 1 A member 1 and 3) and STS (steroid sulfatase). A significant dose-dependent inhibition was found between testosterone levels measured in the culture medium and concentrations of BPA (P = 0.00778 at 24 h and P = 0.0291 at 48 h), BPE (P = 0.039) and BPF (P = 0.00663). The observed BPA and BPA-A-induced inhibition of testosterone production varied according to duration of exposure and BPA/BPA-A concentrations. BPA (10(-9) M; P < 0.05), BPB (10(-9) M; P < 0.05), BPS (10(-9) and 10(-8) M; P < 0.05) and BADGE (10(-5) M; P < 0.05) increased Leydig cell INSL3 production. By contrast, BPE dose dependently inhibited INSL3 (P = 0.0372). Conversely, Sertoli cell function (inhibin B) and germ cell viability were not significantly affected by either bisphenols. N/A. Environmental compounds cannot be deliberately administered to men, justifying the use of an ex vivo approach. A relatively low number of testes samples were available for analysis (n = 3, except for testosterone secretion with n = 5). The active concentrations of BPA and BPA-A used in the study were higher than those found in human biological fluids. Under our experimental conditions, direct exposure to BPA or BPA-A can result in endocrine disturbance in the adult human testis.
ISSN: 0268-1161

hal-01578582
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01578582
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01578582/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01578582/file/Parallel%20assessment%20of%20the%20effects%20of%20bisphenol%20A_accepted.pdf
DOI : 10.1093/humrep/dex093

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Diffusion parameters for HTO, 36Cl−, and 125I− were determined on Upper Toarcian argillite samples from the Tournemire Underground Research Laboratory (Aveyron, France) using the through diffusion technique. The direction of diffusion was parallel to the bedding plane. The purpose of the present study was 3-fold; it was intended (i) to confirm the I− interaction with Upper Toarcian argillite and to verify the effects of initial I− concentration on this affinity, as previously observed by means of radial diffusion experiments, (ii) to highlight any discrepancy between Cl− and I− diffusivity, and (iii) to investigate the effect of an increase of the ionic strength of the solution on the anionic tracers' diffusive behaviour. The results show that the effective diffusion coefficient (De) and diffusion accessible porosity (εa) values obtained with an ionic strength (I.S.) synthetic pore water of 0.01 eq L−1 are: De = 2.35-2.50 × 10−11 m2 s−1 and εa = 12.0-15.0% for HTO, and De = 14.5-15.5 × 10−13 m2 s−1 and εa = 2.5-2.9% for 36Cl−. Because of anionic exclusion effects, anions diffuse slower and exhibit smaller diffusion accessible porosities than HTO, taken as a water tracer. The associated effective diffusion coefficient (De) and rock capacity factor (α) obtained for 125I are: De = 7.00-8.60 × 10−13 m2 s−1 and α = 4.3-7.2%. Such values make it possible to calculate low 125I distribution ratios (0.0057 < RD < 0.0192 mL g−1) which confirm the trend indicating that the 125I rock capacity factor increases with the decrease of the initial I− concentration. Additional through-diffusion experiments were carried out with a higher ionic strength synthetic pore water (I.S. = 0.11 eq L−1). No evolution of HTO diffusion parameters was observed. The anionic tracers' effective diffusion coefficient increased by a factor of two but no clear evolution of their accessible porosity was observed. Such a paradox could be related to the particularly small mean pore size of the Upper Toarcian argillite of Tournemire. The most significant finding of this study is the large discrepancy (factor of two) between the values of the effective diffusion coefficient for 125I and 36Cl. Whatever the ionic strength of the synthetic solution used, 125I exhibited De values two times lower than those of 36Cl. A detailed explanation for this difference cannot be given at present even if a hypothesis based on ion-pairing or on steric-exclusion cannot be excluded. This makes questionable the assumption usually made for quantifying 125I sorption and postulating that 36Cl and 125I would diffuse in the same porosity. In other terms, at Tournemire, 125I sorption could be more pronounced than previously indicated.
ISSN: 0883-2927

hal-00757749
https://hal.archives-ouvertes.fr/hal-00757749
DOI : 10.1016/j.apgeochem.2011.12.017

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
The release of polycyclic aromatic hydrocarbons (PAHs) into the environment has increased very substantially over the last decades. PAHs are hydrophobic molecules which can accumulate in high concentrations in sediments acting then as major secondary sources. Fish contamination can occur through contact or residence nearby sediments or though dietary exposure. In this study, we analyzed certain physiological traits in unexposed fish (F1) issued from parents (F0) exposed through diet to three PAH mixtures at similar and environmentally relevant concentrations but differing in their compositions. For each mixture, no morphological differences were observed between concentrations. An increase in locomotor activity was observed in larvae issued from fish exposed to the highest concentration of a pyrolytic (PY) mixture. On the contrary, a decrease in locomotor activity was observed in larvae issued from heavy oil mixture (HO). In the case of the third mixture, light oil (LO), a reduction of the diurnal activity was observed during the setup of larval activity. Behavioral disruptions persisted in F1-PY juveniles and in their offspring (F2). Endocrine disruption was analyzed using cyp19a1b:GFP transgenic line and revealed disruptions in PY and LO offspring. Since no PAH metabolites were dosed in larvae, these findings suggest possible underlying mechanisms such as altered parental signaling molecule and/or hormone transferred in the gametes, eventually leading to early imprinting. Taken together, these results indicate that physiological disruptions are observed in offspring of fish exposed to PAH mixtures through diet.
ISSN: 0944-1344

hal-01121865
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01121865
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01121865/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01121865/file/Exposures%20of%20zebrafish_accepted.pdf
DOI : 10.1007/s11356-015-4157-8

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Children are exposed to toxic metals and metalloids via their diet and environment. Our objective was to assess the aggregate chronic exposure of children aged 3–6 years, living in France, to As, Cd, Cr, Cu, Mn, Pb, Sb, Sr, and V present in diet, tap water, air, soil and floor dust in the years 2007–2009. Dietary data came from the French Total Diet Study, while concentrations in residential tap water, soil and indoor floor dust came from the ‘Plomb-Habitat’ nationwide representative survey on children's lead exposure at home. Indoor air concentrations were assumed to be equal to outdoor air concentrations, which were retrieved from regulatory measurements networks. Human exposure factors were retrieved from literature. Data were combined with Monte Carlo simulations. Median exposures were 1.7, 0.3, 10.2, 34.1, 60.3, 0.7, 0.1, 44.3, 1.5 and 95th percentiles were 4.4, 0.5, 15.8, 61.3, 98.3, 2.5, 0.1, 111.1, 2.9 μg/kg bw/d for As, Cd, Cr, Cu, Mn, Pb, Sb, Sr, and V respectively. Dietary exposures dominate aggregate exposures, with the notable exception of Pb - for which soils and indoor floor dust ingestion contribute most at the 95th percentile. The strengths of this study are that it aggregates exposures that are often estimated separately, and uses a large amount of representative data. This assessment is limited to main diet and residential exposure, and does not take into account the relative bioavailability of compounds. These results could be used to help target prevention strategies.
ISSN: 0160-4120

inserm-01404061
http://www.hal.inserm.fr/inserm-01404061
http://www.hal.inserm.fr/inserm-01404061/document
http://www.hal.inserm.fr/inserm-01404061/file/rev1%20-%20MS%20Expo%20metals.pdf
DOI : 10.1016/j.envint.2016.10.009

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Introduction Evidence has accumulated that exposure to ambient air pollution during pregnancy may influence preterm birth (PTB) in urban settings. Conversely, this relation has barely been investigated in rural areas where individual characteristics (demographic, socioeconomic, and psychosocial factors) and environmental co-exposures may differ. Objective We examined the association between prenatal exposure to traffic-related air pollution and PTB among pregnant women from the PELAGIE mother–child cohort (Brittany, France, 2002–2006) living in urban (n=1550) and rural (n=959) settings. Methods Women’s residences were classified as either urban or rural according to the French census bureau rural–urban definitions. Nitrogen dioxide (NO2) concentrations at home addresses were estimated from adjusted land-use regression models as a marker of traffic-related pollution. Associations between NO2 concentrations and PTB were assessed with logistic regression models. Results Prevalence of PTB was similar among women living in urban (3.2%) and in rural (3.5%) settings. More positive socioeconomic characteristics and health behaviors but more single-parent families were observed among urban women. NO2 exposure averaged 20.8±6.6 µg m−3 for women residing in urban areas and 18.8±5.6 µg m−3 for their rural counterparts. A statistically significant increased risk of PTB was observed among women exposed to NO2 concentrations ≥16.4 µg m−3 and residing in urban areas but not among their rural counterparts. Discussion The results of this study, conducted in a region with interspersed urban–rural areas, are in line with previous findings suggesting an increased risk of PTB associated with higher NO2 concentrations for women living in urban areas. The absence of association among their rural counterparts for whom exposure levels were similar suggests that environmental mixtures and psychosocial inequalities might play a role in this heterogeneity
ISSN: 0013-9351

hal-01165108
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01165108
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01165108/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01165108/file/Air%20pollution%20%26%20preterm%20birth%20PELAGIE_HAL-accepted.pdf
PUBMED : 26092808

Éditeur(s) : Université de Paris 7
Résumé : The Seine estuary and its adjacent region Pays de Caux are two significant sources of mercury for coastal marine environments. It is carried through fluvial means for the Seine bay and through karstic fresh water emergences for Pays de Caux's coastal area. Mercury cycle in the Seine estuary and bay is affected by additional anthropical activities. The estuary's maximal turbidity area acts like a trap and a chemical reactor for fluvial mercury. Within this area, we can confirm: (i) the non conservative behaviour of dissolved mercury; (ii) mercury enrichment of particles when comparing the Seine's and marine environment and we suggest mercury particle redistribution from the organic fraction to the oxyhydroxydes fraction. A large fraction of mercury is exported in this state towards coastal areas. Mercury reduction in surface coastal waters and its atmospherical recycling are major phenomena. Photoreduction and biological reduction play quantitative roles equivalent to total mercury recycling via the atmosphere corresponding approximately to 30 % of fluvial exchanges. We are demonstrating that reactive forms of mercury are supporting photoreduction. Mercury behaviour within Pays de Caux's karst depends of the hydrogeological context of the system (time and flow speed, turbidity, flow); regardless of the speciation and/or partition in underground waters, the total amount of mercury in intertidal areas is quantitatively the same as in the Seine estuary. Mercury brought through intertidal emergences (karstic exudations) is not « filtered » by a maximal turbidity area and is more widely bio-available for mussels than in the Seine estuary. Even being free from growth factor influences through simple models, mussels found in Pays de Caux still show one of the highest mercury contamination on the French coast; for the first time this places the emphasis on how much mercury is brought from underground waters to the coastal environment. Surface complexation modelisation tests are able to reproduce the major part of mercury partition in the Seine estuary and bay if a very low mercury exchangeable fraction and minimum complexation parameters are taken into account; thermodynamic calculations also suggest that a strong or highly concentrated « dissolved » ligand must be present in the water in order to compete with chlorocomplex formations and explain our measures.
L'estuaire de la Seine et la région adjacente du Pays de Caux sont deux sources significatives en mercure pour le milieu marin côtier. Les apports sont d'une part fluviatiles en ce qui concerne la Baie de Seine et karstiques via des émergences d'eau douce pour la zone côtière du Pays de Caux. Le cycle du mercure en estuaire et baie de Seine est perturbé par les apports liés aux activités anthropiques. La zone de turbidité maximum de l'estuaire joue le rôle de piège et de réacteur chimique pour le mercure fluviatile. Au sein de cette zone, nous mettons en évidence : (i) un comportement non-conservatif du mercure dissous; (ii) un enrichissement en mercure des particules par rapport à celles de la Seine et du milieu marin et suggérons une redistribution du mercure particulaire de la fraction organique vers la fraction oxyhydroxydes. C'est sous cette forme qu'une fraction importante du mercure est exportée vers la zone côtière. La réduction du mercure dans les eaux côtières de surface et son recyclage atmosphérique sont des phénomènes majeurs. En effet, la photoréduction et la réduction biologique jouent des rôles quantitativement équivalents avec un recyclage total du mercure via l'atmosphère correspondant à environ 30% des apports fluviatiles. Nous montrons que les formes réactives du mercure constituent le substrat de la photoréduction. Le comportement du mercure au sein du karst du Pays de Caux dépend du contexte hydrogéologiques du système (temps et vitesse de circulation, turbidité, débit) ; quelle que soit la spéciation et/ou la partition dans les eaux souterraines, l'apport en mercure total à la zone intertidale est quantitativement du même ordre de grandeur que les apports de la Seine. Le mercure apporté par les émergences intertidales (exutoires karstiques) n'est pas « filtré » par une zone de turbidité maximale et se trouve plus largement biodisponible pour les moules qu'en estuaire de Seine. En s'affranchissant, par des modèles simples, de l'influences des facteurs de croissance, les moules du Pays de Caux affichent toujours une contamination par le mercure parmi les plus élevées du littoral français; ceci met pour la première fois l'emphase sur l'importance de l'apport en mercure par des eaux souterraines dans un environnement côtier. Les essais de modélisation de complexation de surface reproduisent la majeure partie de la partition du mercure dans l'estuaire et la baie de Seine si l'on tient compte d'une fraction échangeable en mercure très faible et de paramètres de complexation minimums ; les calculs thermodynamiques suggèrent aussi qu'un ligand « dissous » fort ou présent à de fortes concentrations doit être présent dans l'eau afin d'entrer en compétition avec la formation de chlorocomplexes et expliquer nos mesures.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2001/these-1842.pdf
http://archimer.ifremer.fr/doc/00000/1842/

Éditeur(s) : HAL CCSD
Résumé : Pregnancy is a sensitive and critical period for the development of the child and the health of adults-to-be. The biological and physiological adaptation of the body dealing physical and psychosocial stressors during this period may exert its effects in adulthood (and possibly over several generations). This delayed toxicity presupposes intrinsically the need to study the effects of exposure to environmental risk factors during fetal life using a holistic approach involving risk factors at both the micro (individual characteristics) and the macro level (physical and psycho-social context). Given the heterogeneity of the Breton territory in which this work was conducted, we explored whether the impact of social inequalities and the physical environment (air pollution) on birth outcomes (fetal growth and the risk of prematurity) could be modified according to an urban or rural place of residence. This work was based on data collected as part of the Breton mother-child cohort PELAGIE, which had included 3421 pregnant women between 2002- 2006. The anthropometric parameters and gestational age at birth were measured by medical personnel at delivery. We defined urban and rural areas according to the definition of “urban units” from the National Census Bureau (INSEE). The annual concentrations of air pollution (nitrogen dioxide (NO2)) were estimated using a land-use regression modeled at a 100 m scale and developed as part of an European project. Finally, neighbourhood deprivation was estimated using a composite index developed at census blocks level and whose use was legitimated over both urban and rural areas. Neighbourhood deprivation was associated with an increased risk of infants with fetal growth restriction, only for women living in rural areas. We also observed an increased risk of preterm birth associated with NO2 concentrations > 16.4 μg.m-3, only among women residing in urban areas. The associations between air pollution and fetal growth, although sex-specific, did not seem on the other hand, to vary significantly according to the urban-rural spectrum. This work confirms the need to explore the influence of both social and environmental inequalities on intrauterine development, and to assess the role of place-based factors, such as the urban-rural context, in shaping these inequalities.
La grossesse est une période sensible et déterminante pour le développement de l’enfant et l’état de santé à l’âge adulte. L'adaptation biologique et physiologique de l'organisme face à des « stresseurs » physiques et psychosociaux au cours de cette période peut ainsi exercer ses effets à l'âge adulte (et possiblement sur plusieurs générations). Cette toxicité différée suppose intrinsèquement la nécessité d’étudier les conséquences des expositions environnementales au cours de la vie foetale et ce suivant une approche holistique intégrant autant les facteurs de risque à des niveaux micro (caractéristiques individuelles) et macro (expositions physiques externes et contexte psycho-social). Etant donné l’hétérogénéité du territoire breton dans lequel s’inscrit ce travail de thèse, nous avons cherché à explorer l’impact des inégalités sociales et de l’environnement physique (pollution atmosphérique) sur l’issue de la grossesse (croissance foetale et risque de prématurité) indépendamment chez des femmes enceintes résidant dans des zones urbaines et rurales. Ce travail s’est appuyé sur les données issues de la cohorte bretonne mère-enfant PELAGIE, qui a inclus 3421 femmes enceintes entre 2002- 2006. Les paramètres anthropométriques et l’âge gestationnel à la naissance ont été renseignés à l’accouchement par le personnel médical. Le contexte urbain et rural breton a été caractérisé à partir de la définition des unités urbaines de l’INSEE. Les concentrations annuelles de pollution atmosphérique (dioxyde d’azote (NO2)) ont été modélisées à une échelle de 100 m à partir d’un modèle de "land-use regression" développé à l’échelle européenne. Enfin, le niveau socio-économique des IRIS a été estimé à l’aide d’un indice de désavantage social - construit à partir des données du recensement de l’INSEE et dont la validité et l’adaptabilité à des territoires à la fois urbains et ruraux a été examinée au préalable. Nos résultats suggèrent une influence délétère d’un contexte de vie socioéconomique défavorable sur la croissance intra-utérine, spécifiquement chez les femmes résidant en milieu rural. Nous avons également observé une augmentation du risque de prématurité associée à des niveaux > 16.4 μg.m-3 de NO2 dans l’air, à l’inverse, uniquement chez les femmes résidant dans des zones urbaines. Les associations entre l’exposition à la pollution atmosphérique et les marqueurs de la croissance intra-utérine, bien que sexe-spécifiques, ne semblent en revanche pas varier sensiblement suivant le gradient urbain-rural. Ce travail confirme la nécessité d’évaluer l’influence des inégalités sociales et environnementales sur le développement intra-utérin et de considérer l’importance et le rôle du contexte de vie, notamment urbain-rural, dans la formation de ces inégalités.
https://tel.archives-ouvertes.fr/tel-01308518

NNT : 2015REN1B010
tel-01308518
https://tel.archives-ouvertes.fr/tel-01308518
https://tel.archives-ouvertes.fr/tel-01308518/document
https://tel.archives-ouvertes.fr/tel-01308518/file/BERTIN_M--lanie.pdf