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Effects of an environmentally relevant concentration of diuron on oyster genitors during gametogenesis: responses of early molecular and cellular markers and physiological impacts Full text
2016
Akcha, Farida | Barranger, Audrey | Bachere, Evelyne | Berthelin, C. Heude | Piquemal, D. | Alonso, P. | Sallan, R. Rondon | Dimastrogiovanni, G. | Porte, C. | Menard, Dominique | Szczybelski, A. | Benabdelmouna, Abdellah | Auffret, M. | Rouxel, Julien | Burgeot, Thierry
Effects of an environmentally relevant concentration of diuron on oyster genitors during gametogenesis: responses of early molecular and cellular markers and physiological impacts Full text
2016
Akcha, Farida | Barranger, Audrey | Bachere, Evelyne | Berthelin, C. Heude | Piquemal, D. | Alonso, P. | Sallan, R. Rondon | Dimastrogiovanni, G. | Porte, C. | Menard, Dominique | Szczybelski, A. | Benabdelmouna, Abdellah | Auffret, M. | Rouxel, Julien | Burgeot, Thierry
Genitors of the Pacific oyster Crassostrea gigas were submitted during gametogenesis to a short pulse exposure to the herbicide diuron at a realistic environmental concentration. Histological analysis showed no effect of diuron on gametogenesis course, sex ratio and reproductive effort. A non-significant increase in testosterone and progesterone levels was observed in genitors exposed to the herbicide. At cell level, diuron exposure was shown to modulate the phagocytic activity of circulating hemocytes. The results of a transcriptional analysis showed that diuron affected the expression of genes belonging to functions known to play a major role during oyster gametogenesis such as gene transcription regulation, DNA replication and repair, DNA methylation and cytokinesis. Taking into account the results we previously obtained on the same genitors, this study showed a negative effect of diuron on oyster reproduction by inducing both structural and functional modifications of the DNA.
Show more [+] Less [-]Effects of an environmentally relevant concentration of diuron on oyster genitors during gametogenesis: responses of early molecular and cellular markers and physiological impacts Full text
2016
Akcha, F. | Barranger, A. | Bachère, E. | Berthelin, C Heude | Piquemal, D. | Alonso, P. | Sallan, R Rondon | Dimastrogiovanni, G. | Porte, C. | Menard, D. | Szczybelski, A. | Benabdelmouna, A. | Auffret, M. | Rouxel, J. | Burgeot, T.
Genitors of the Pacific oyster Crassostrea gigas were submitted during gametogenesis to a short pulse exposure to the herbicide diuron at a realistic environmental concentration. Histological analysis showed no effect of diuron on gametogenesis course, sex ratio and reproductive effort. A non-significant increase in testosterone and progesterone levels was observed in genitors exposed to the herbicide. At cell level, diuron exposure was shown to modulate the phagocytic activity of circulating hemocytes. The results of a transcriptional analysis showed that diuron affected the expression of genes belonging to functions known to play a major role during oyster gametogenesis such as gene transcription regulation, DNA replication and repair, DNA methylation and cytokinesis. Taking into account the results we previously obtained on the same genitors, this study showed a negative effect of diuron on oyster reproduction by inducing both structural and functional modifications of the DNA.
Show more [+] Less [-]Assessment of the contamination of marine fauna by chlordecone in Guadeloupe and Martinique (Lesser Antilles) Full text
2016
Dromard, Charlotte | Bodiguel, Xavier | Lemoine, Soazig | Bouchon-navaro, Yolande | Reynal, Lionel | Thouard, Emmanuel | Bouchon, Claude
Assessment of the contamination of marine fauna by chlordecone in Guadeloupe and Martinique (Lesser Antilles) Full text
2016
Dromard, Charlotte | Bodiguel, Xavier | Lemoine, Soazig | Bouchon-navaro, Yolande | Reynal, Lionel | Thouard, Emmanuel | Bouchon, Claude
Chlordecone is an organochlorine pesticide, used in the Lesser Antilles from 1972 to 1993 to fight against a banana weevil. That molecule is very persistent in the natural environment and ends up in the sea with runoff waters. From 2003 to 2013, seven campaigns of samplings have been conducted to evaluate the level of contamination of fish, crustaceans, and mollusks. The present study is the first assessment and the first comparison of the concentrations of chlordecone between marine areas, taxonomic groups, and ecological factors like trophic groups or preferential habitat of fish species. The four most contaminated marine areas are located downstream the contaminated rivers and banana plantations. Crustaceans seemed to be more sensitive to the contamination than fish or mollusks. Finally, when comparing contamination of fish according to their ecology, we found that fish usually living at the border of mangrove and presenting detritivores-omnivores diets were the most contaminated by chlordecone. These results are particularly useful to protect the health of the local population by controlling the fishing and the commercialization of seafood products, potentially contaminated by chlordecone.
Show more [+] Less [-]Assessment of the contamination of marine fauna by chlordecone in Guadeloupe and Martinique (Lesser Antilles) Full text
2016
Dromard, Charlotte R. | Bodiguel, Xavier | Lemoine, Soazig | Bouchon-Navaro, Yolande | Reynal, Lionel | Thouard, Emmanuel | Bouchon, Claude
Chlordecone is an organochlorine pesticide, used in the Lesser Antilles from 1972 to 1993 to fight against a banana weevil. That molecule is very persistent in the natural environment and ends up in the sea with runoff waters. From 2003 to 2013, seven campaigns of samplings have been conducted to evaluate the level of contamination of fish, crustaceans, and mollusks. The present study is the first assessment and the first comparison of the concentrations of chlordecone between marine areas, taxonomic groups, and ecological factors like trophic groups or preferential habitat of fish species. The four most contaminated marine areas are located downstream the contaminated rivers and banana plantations. Crustaceans seemed to be more sensitive to the contamination than fish or mollusks. Finally, when comparing contamination of fish according to their ecology, we found that fish usually living at the border of mangrove and presenting detritivores-omnivores diets were the most contaminated by chlordecone. These results are particularly useful to protect the health of the local population by controlling the fishing and the commercialization of seafood products, potentially contaminated by chlordecone.
Show more [+] Less [-]Decadal increase in the number of recreational users is concentrated in no-take marine reserves Full text
2016
Gonson, Charles | Pelletier, Dominique | Gamp, Elodie | Preuss, Bastien | Jollit, Isabelle | Ferraris, Jocelyne
Decadal increase in the number of recreational users is concentrated in no-take marine reserves Full text
2016
Gonson, Charles | Pelletier, Dominique | Gamp, Elodie | Preuss, Bastien | Jollit, Isabelle | Ferraris, Jocelyne
In coastal areas, demographic increase is likely to result in greater numbers of recreational users, with potential consequences on marine biodiversity. These effects may also occur within Marine Protected Areas (MPAs), which are popular with recreational users. Our analysis builds on data collected over a ten-year period during three year-round surveys to appraise changes in recreational boating activities in coral ecosystems. Results show that the number of boaters has greatly increased, particularly so within MPAs during weekends and the warm season, when peaks in boat numbers have become more frequent. We also observed that the number of anchored boats has increased over the period. These changes may be resulting in biophysical impacts that could be detrimental to conservation objectives in MPAs. This steady increase over time may cause changes in the spatial and temporal distribution of users and in their practices, thus highlighting the importance of monitoring recreational activities.
Show more [+] Less [-]Decadal increase in the number of recreational users is concentrated in no-take marine reserves Full text
2016
Gonson, Charles | Pelletier, Dominique | Gamp, Elodie | Preuss, Bastien | Jollit, Isabelle | Ferraris, Jocelyne
In coastal areas, demographic increase is likely to result in greater numbers of recreational users, with potential consequences on marine biodiversity. These effects may also occur within Marine Protected Areas (MPAs), which are popular with recreational users. Our analysis builds on data collected over a ten-year period during three year-round surveys to appraise changes in recreational boating activities in coral ecosystems. Results show that the number of boaters has greatly increased, particularly so within MPAs during weekends and the warm season, when peaks in boat numbers have become more frequent. We also observed that the number of anchored boats has increased over the period. These changes may be resulting in biophysical impacts that could be detrimental to conservation objectives in MPAs. This steady increase over time may cause changes in the spatial and temporal distribution of users and in their practices, thus highlighting the importance of monitoring recreational activities.
Show more [+] Less [-]The role of social marketing, marine turtles and sustainable tourism in reducing plastic pollution Full text
2016
Eagle, Lynne | Hamann, Mark | Low, David R.
Environmental plastic pollution constitutes a significant hazard to marine turtles, human health and well-being. We describe a transdisciplinary approach to draw together findings from diverse disciplines in order to highlight key environmental pollution problems and their consequences, together with social marketing-based strategies to address the problems. The example of plastic pollution and impacts to marine turtles illustrates the severity of the problem. Wildlife tourism and sustainable tourism activity have not focussed on specific behaviours to change and have had minimal impact on subsequent human behaviour regarding environmental issues, indicating the need for new strategies. Social marketing principles offer promise, but there is a need to investigate the utility of various theoretical foundations to aid the design and implementation of interventions. We offer insight towards using sophisticated multi-method research to develop insights into behaviours and segmentation-based strategies, that can aid the identification of barriers to, and enablers of, sustained behaviour change.
Show more [+] Less [-]Effect of nutrient enrichment on the source and composition of sediment organic carbon in tropical seagrass beds in the South China Sea Full text
2016
Liu, Songlin | Jiang, Zhijian | Zhang, Jingping | Wu, Yunchao | Lian, Zhonglian | Huang, Xiaoping
To assess the effect of nutrient enrichment on the source and composition of sediment organic carbon (SOC) beneath Thalassia hemprichii and Enhalus acoroides in tropical seagrass beds, Xincun Bay, South China Sea, intertidal sediment, primary producers, and seawater samples were collected. No significant differences on sediment δ13C, SOC, and microbial biomass carbon (MBC) were observed between T. hemprichii and E. acoroides. SOC was mainly of autochthonous origin, while the contribution of seagrass to SOC was less than that of suspended particulate organic matter, macroalgae and epiphytes. High nutrient concentrations contributed substantially to SOC of seagrass, macroalgae, and epiphytes. The SOC, MBC, and MBC/SOC ratio in the nearest transect to fish farming were the highest. This suggested a more labile composition of SOC and shorter turnover times in higher nutrient regions. Therefore, the research indicates that nutrient enrichment could enhance plant-derived contributions to SOC and microbial use efficiency.
Show more [+] Less [-]Marine environmental protection: An application of the nanometer photo catalyst method on decomposition of benzene Full text
2016
Lin, Mu-Chien | Kao, Jui-Chung
Bioremediation is currently extensively employed in the elimination of coastal oil pollution, but it is not very effective as the process takes several months to degrade oil.Among the components of oil, benzene degradation is difficult due to its stable characteristics. This paper describes an experimental study on the decomposition of benzene by titanium dioxide (TiO2) nanometer photocatalysis. The photocatalyst is illuminated with 360-nm ultraviolet light for generation of peroxide ions. This results in complete decomposition of benzene, thus yielding CO2 and H2O. In this study, a nonwoven fabric is coated with the photocatalyst and benzene. Using the Double-Shot Py–GC system on the residual component, complete decomposition of the benzene was verified by 4h of exposure to ultraviolet light. The method proposed in this study can be directly applied to elimination of marine oil pollution. Further studies will be conducted on coastal oil pollution in situ.
Show more [+] Less [-]Mobile monitoring of particulate matter: State of art and perspectives Full text
2016
Gozzi, Fernando | Della Ventura, Giancarlo | Marcelli, A.
Due to the socio-economic impact and the consequences on human health, the pollution associated to Particulate Matter (PM) represents one of the main emergences at a global scale. For these reasons, in the last decade we assisted to a continuously increasing interest in the mobile monitoring of PM on a regional and a local scale. Here we summarize the current status in this field, outlining the critical issues and the perspectives. The growing availability of instruments designed and optimized to the real-time monitoring of the air quality, considerably increased the spatial and temporal resolution of available datasets, actually improving air pollution maps and forecast models. However, several issues are still unresolved, particularly in terms of data representativeness. Indeed, the future PM monitoring devices have to be designed to support the decisional process but also the management of environmental emergencies in urban and industrial areas. The future of these devices is certainly the development of compact systems that will make possible a real-time characterization of size distribution, morphology, and chemical composition of the airborne particles.
Show more [+] Less [-]Spatial variation and provenance of atmospheric trace elemental deposition in Beijing Full text
2016
Zheng, Xiaoxia | Guo, Xiaoyu | Zhao, Wenji | Shu, Tongtong | Xin, Yanan | Yan, Xing | Xiong, Qiulin | Chen, Fantao | Lv, Ming
Atmospheric dry deposition samples were collected in urban and suburban areas of Beijing during a coal-burning period. Chemical characteristics of lanthanoid elements (La–Lu) and five heavy metals (Cr, Co, Mo, Cd, and Pb) were analyzed to determine the variation in spatial scale and deposition provenances. Factor analysis and ternary diagrams were used to identify principle pollution sources. The LaCeSm ternary diagram was used to identify oil refineries using fluid catalytic converters and steel plants, but could not differentiate crustal materials. Lanthanoid characteristic parameters showed similarity between deposition and soil in the local and southwest area in the vicinity of Beijing. Analysis of the five heavy metals enabled discrimination of contaminants originating from human activities. Cd, Pb, and Mo were found to originate from vehicular traffic, whereas Co and Cr originated from industrial emissions and coal combustion. Discriminant analysis established the causes of spatial variation. The result shows that Co, Mo, and Pb can mark the differences between urban and suburban sites. From the PbMoCo plot, it was inferred that the different chemical characters are mainly due to the differing origins of depositions. Deposition samples in suburban areas are principally influenced by soil, chimney soot, and fertilizer, whereas those in urban area are mainly affected by traffic emissions.
Show more [+] Less [-]Determination of ambient air concentrations and personal exposure risk levels of outdoor workers to carbonyl compounds and BTEX in the inner city of Bangkok, Thailand Full text
2016
Kanjanasiranont, Navaporn | Prueksasit, Tassanee | Morknoy, Daisy | Tunsaringkarn, Tanasorn | Sematong, Saowanee | Siriwong, Wattasit | Zapaung, Kalaya | Rungsiyothin, Anusorn
The ambient and personal air concentrations of benzene, toluene, ethylbenzene and xylenes (BTEX) and carbonyl compounds (CCs) were investigated in Pathumwan district, Bangkok (Thailand), a congested area with a high level of traffic-related air pollution. The potential health risk of three representative groups of street workers (street vendors, motorcycle taxi driver and security guards) exposed to these substances was estimated. The personal air exposure and ambient air samples were collected in the rainy (September 2012) and summer (March 2013) seasons. The 8-h average formaldehyde and acetaldehyde exposure levels for both personal and ambient air concentrations were found to be the major CCs. The highest mean ambient air level of formaldehyde (20.1 μg/m3) was found at the roadside at a busy intersection next to department stores. The highest level of acetaldehyde (9.17 μg/m3) was found in a location with a high traffic load close to the hospital and university. For BTEX, the greatest average concentration was observed around the site located near a bus stop (45.5 μg/m3). In terms of the personal exposure concentrations of CCs and BTEX, no statistically significant differences were found among all sampled locations for street vendors and motorcycle taxi drivers. With respect to the health risk assessment, at a 95% confidence interval (CI) of cancer risk, benzene posed the highest risk followed by formaldehyde and then acetaldehyde (5.36E-06–1.48E-05, 5.58E-06–1.91E-05 and 1.03E-05–5.93E-05 for street vendors, motorcycle taxi driver and security guards) while the 95% CI non-cancer risk values were at an acceptable level. Nevertheless, there were no significant differences in the total cancer risk among the different groups of workers. From the health risk assessment, benzene and formaldehyde were the major traffic related air pollutants that likely affected the human health in this area.
Show more [+] Less [-]Measurement of aerosol nanoparticles from a combustion particle generator by using three types of dilutors Full text
2016
Lee, Byung Uk | Bae, Gwi Nam
Ultrafine aerosol nanoparticles created from combustion were measured by using three types of dilutors: a simple mixing dilutor, an ejector dilutor, and a rotational disk dilutor. The original particle size distribution from combustion was compared to the estimated distribution from these dilutors. The results showed that ultrafine aerosol nanoparticles maintained their particle size distribution, while particle concentrations decreased 10–20 fold in the dilution processes. Therefore, the dilutors not only diluted the aerosol nanoparticle concentration to the level of the measurement devices, but also helped estimate the shape of aerosol particle size distribution, particularly for ultrafine aerosol nanoparticles from combustion.
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