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Consequences of Different Types of Littoral Zone Light Pollution on the Parental Care Behaviour of a Freshwater Teleost Fish Full text
2016
Foster, Jordann G. | Algera, Dirk A. | Brownscombe, Jacob W. | Zolderdo, Aaron J. | Cooke, Steven J.
Ecological light pollution occurs when artificial lights disrupt the natural regimes of individual organisms or their ecosystems. Increasing development of shoreline habitats leads to increased light pollution (e.g., from cottages, docks, automobile traffic), which could impact the ecology of littoral zones of lakes and rivers. Smallmouth bass (Micropterus dolomieu) engage in sole paternal care, guarding their nest continually, day and night, to protect their developing offspring. Any alterations to their behaviour—either directly because of the response to light or indirectly due to changes in nest predator activity and associated response of the bass—could lead to increased energetic demands for fish that have a fixed energy budget and ultimately reduce reproductive success. To examine this issue, tri-axial accelerometer biologgers were externally attached to nesting smallmouth bass during the egg stage to determine whether light pollution (i.e., dock lights with low levels of continuous light and spotlights with high intensity irregular light simulating automobile traffic) altered behaviour of nesting males relative to control fish. Our study revealed that both types of light pollution increased overall bass activity level compared with the control group. The intermittent light treatment group had the highest activity and exhibited large fluctuations between night and day activity levels. Fish in the continual light treatment group displayed statistically higher activity than the control fish but showed limited fluctuations between day and night activity levels. Our results suggest that continuous or intermittent light sources, common in shoreline habitats that have been developed, have the potential to alter the behaviour and thus energy use of nest-guarding fish. This study contributes to the growing body of literature on the ecological consequences of light pollution in aquatic ecosystems.
Show more [+] Less [-]The Effect of Air Pollution on Leaf Iron (Fe) Concentration and Activity of Fe-Dependent Antioxidant Enzymes in Maple Full text
2016
Iron (Fe) nutrition status and activity of Fe-dependent enzymes is suggested to be affected by air pollution. This study was aimed to investigate changes in leaf Fe, zinc (Zn), chlorophyll (a, b), and carotenoid concentration and activity of catalase (CAT) and peroxidase (POX) in the leaves of maple (Acer negundo L.) with distance from two major sources of air pollution, i.e., Oil Refinery of Shiraz (ORS) operations and urban traffic of Imam Hossein square (AS) in Shiraz, Iran. By increasing the distance from the ORS, Fe, Zn, and chlorophyll concentration in the maple leaves increased. These changes were associated with lower intensity of chlorosis symptoms on the leaves of maple trees with distance from the ORS. Leaf activity of CAT increased with increasing distance from the ORS. Changes in concentration of carotenoids and activity of POX did not follow a distinct trend with distance from both pollution sources. No regular pattern was observed for changes in the measured parameters with distance from the urban traffic of Imam Hossein square (AS), as another major source of air pollution in the studied region. This was due to irregular changes in the concentrations of air pollutants across the sampling pathway. According to the results, significant impairment in Fe nutritional status is expected for plants exposed to the air pollution, although further studies are needed to clarify the physiological reasons of Fe chlorosis under air pollution stress.
Show more [+] Less [-]Comparison Between Sorption and Sono-Sorption Efficiencies, Equilibriums and Kinetics in the Uptake of Direct Red 23 from the Aqueous Solutions Full text
2016
Oguz, Ensar | Bire, Murat | Nuhoglu, Yasar
Using ZnO nanoparticles, comparisons between sorption and sono-sorption efficiencies, equilibrium and kinetics in Direct Red 23 have been researched under the various experimental conditions. Pseudo-second-order model was practiced for the experimental data. The mechanism of the dye uptake was clarified based on the analyses of X-ray diffraction (XRD) and scanning electron microscopy (SEM). Brunauer-Emmett-Teller (BET) surface area and total pore volume of the nanoparticles were obtained. The highest Direct Red 23 (DR23) removal efficiencies by sorption and sono-sorption processes were determined as 78.6 and 96.8 %, respectively. Experimental data have been evaluated according to Langmuir, Freundlich and Dubinin-Radushkevich. The mean energies of sorption and sono-sorption processes were calculated to be 16.22 and 25.41 kJ/mol, respectively. Arrhenius equation was used to calculate the activation energies. ΔH° and ΔG° values indicated that sorption and sono-sorption processes were endothermic processes. But, negative free energy values of ΔG° indicated that sorption and sono-sorption processes were favoured at high temperatures.
Show more [+] Less [-]Status of hormones and painkillers in wastewater effluents across several European states—considerations for the EU watch list concerning estradiols and diclofenac
2016
Schröder, P. | Helmreich, B. | Škrbić, B. | Carballa, M. | Papa, M. | Pastore, C. | Emre, Z. | Oehmen, A. | Langenhoff, A. | Molinos, M. | Dvarioniene, J. | Huber, C. | Tsagarakis, K.P. | Martinez-Lopez, E. | Pagano, S.M. | Vogelsang, C. | Mascolo, G.
Present technologies for wastewater treatment do not sufficiently address the increasing pollution situation of receiving water bodies, especially with the growing use of personal care products and pharmaceuticals (PPCP) in the private household and health sector. The relevance of addressing this problem of organic pollutants was taken into account by the Directive 2013/39/EU that introduced (i) the quality evaluation of aquatic compartments, (ii) the polluter pays principle, (iii) the need for innovative and affordable wastewater treatment technologies, and (iv) the identification of pollution causes including a list of principal compounds to be monitored. In addition, a watch list of 10 other substances was recently defined by Decision 2015/495 on March 20, 2015. This list contains, among several recalcitrant chemicals, the painkiller diclofenac and the hormones 17β-estradiol and 17α-ethinylestradiol. Although some modern approaches for their removal exist, such as advanced oxidation processes (AOPs), retrofitting most wastewater treatment plants with AOPs will not be acceptable as consistent investment at reasonable operational cost. Additionally, by-product and transformation product formation has to be considered. The same is true for membrane-based technologies (nanofiltration, reversed osmosis) despite of the incredible progress that has been made during recent years, because these systems lead to higher operation costs (mainly due to higher energy consumption) so that the majority of communities will not easily accept them. Advanced technologies in wastewater treatment like membrane bioreactors (MBR) that integrate biological degradation of organic matter with membrane filtration have proven a more complete elimination of emerging pollutants in a rather cost- and labor-intensive technology. Still, most of the presently applied methods are incapable of removing critical compounds completely. In this opinion paper, the state of the art of European WWTPs is reflected, and capacities of single methods are described. Furthermore, the need for analytical standards, risk assessment, and economic planning is stressed. The survey results in the conclusion that combinations of different conventional and advanced technologies including biological and plant-based strategies seem to be most promising to solve the burning problem of polluting our environment with hazardous emerging xenobiotics.
Show more [+] Less [-]Examination of Lead and Cadmium in Water-based Paints Marketed in Nigeria Full text
2016
Ajoke F. I. Apanpa-Qasim | Adebola A. Adeyi | Sandeep N. Mudliar | Karthik Raghunathan | Prasant Thawale
Background. In spite of the availability of substitutes for lead and cadmium compounds in paints, manufacturers continue to produce paints with high levels of these metals. As the population continues to grow and there is a continued shift from oil-based to water-based paints, the sales and use of these paints will increase the exposure of humans and the environment to these metals. Objectives. We measured the levels of lead (Pb) and cadmium (Cd) in 174 paint samples marketed in Lagos and Ibadan, Nigeria. Paint samples from different manufacturers registered with and without Standards Organization of Nigeria (SON) were considered. Methods. Samples were acid digested using a microwave digester and the levels of the elements were determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). Discussion. The levels of Cd and Pb (dry weight) in all samples ranged from 98–1999 μg/g and 170–3231 μg/g, respectively. All the samples were above the permissible limits of 90 ppm of the US Consumer Product Safety Commission and 100 ppm limit of the European Union (EU) for Pb and Cd in paint. Conclusions. We concluded that water-based paints marketed in Nigeria still contain substantial amounts of lead and cadmium which are detrimental to human health and the entire ecosystem. These metals are among the EU priority metals due to the increased risk of occupational exposure to humans and vulnerable groups such as children. Competing Interests. The authors declare no competing financial interests.
Show more [+] Less [-]Analysis of Artisanal Small-scale Gold Mining Sector in West Sumbawa Regency, Indonesia Full text
2016
Baiq Dewi Krisnayanti | Ivano Vassura | Maywin Dwi Asmara | Ardiana Ekawanti | Herman Suheri
Background. The high value of gold reserves in West Sumbawa Regency (WSR) and West Nusa Tenggara Province, Indonesia has resulted in an increase in small-scale gold mining activity in this area. Artisanal and small-scale gold mining (ASGM) is an attractive alternative livelihood for rural workers because it has good potential to improve the wealth of a community. Miners need very little training to mine gold and the transition from traditional farming or fishing is easy to make. However, the key environmental consequence of ASGM in West Sumbawa is the extensive use of mercury and its impact on human health. Objectives. The ASGM activity in WSR is quite recent when compared to other ASGM activity in Indonesia. The current study was conducted to better understand the lifestyle, extent of mercury exposure, and the health of people living in WSR, West Nusa Tenggara Province, Indonesia. Methods. The present study was designed as a purposive field sampling study conducted in WSR, West Nusa Tenggara Province, Indonesia. The subjects were miners and families from three different sites within the WSR: individuals directly exposed to mercury, indirectly exposed individuals and non-exposed individuals. Hair mercury analysis was done with all subjects. Health questionnaires, physical examinations and socio-economic surveys were conducted with exposed subjects. Results. The ASGM sector in the WSR consists of a high number of migrant workers who have a great economic impact on the local area, high mercury use, a great deal of illegal mercury trading, and a high mercury concentration (>13 mg/kg) in their hair. The results suggest that ASGM activities affect the health of exposed and indirectly exposed individuals. Conclusions. The current scale of ASGM activity in the WSR is predicted to rise. ASGM activities in the WSR is an important challenge that needs to be addressed. Competing Interests. The authors declare no competing financial interests. Informed Consent. Obtained Ethical Approval. The protocols and informed consent documents were approved by the Ethics Committee (Medical Faculty) of the University of Mataram, West Nusa Tenggara Province, Indonesia.
Show more [+] Less [-]Biodegradation of Methanol Using Thiosulphate as an Electron Acceptor Under Anaerobic Conditions Full text
2016
Mekonnen Maschal Tarekegn
Background. Methanol is a volatile organic compound commonly found in the effluent of the pulp and paper industries. Because of its toxicity, methanol can cause metabolic acidosis, neurologic sequelae, and even death when ingested. Information on biokinetic activity such as biodegradation rate of methanol and thiosulphate, biomass growth rate and biomass yield coefficient is limited in the literature. Objectives. To study the biomass growth rate and biomass yield coefficients of methanol and thiosulphate biodegradation. This research aims to increase knowledge of how to reduce the emission of toxic gas to the environment. Methods. The biodegradation trends of both methanol and thiosulphate were studied under anaerobic conditions using batch experiments at ambient temperature and alkaline conditions. Both supplement each other for their degradation. Methanol is an electron donor, whereas thiosulphate acts as an electron acceptor. A mixed culture from a previously used biomass in a biotrickling filter reactor from theUnited Nations Educational, Scientific and Cultural Organization (UNESCO), International Graduate Water Education Facility and fresh activated sludge from the Harnaschpolder wastewater treatment plant were used as a biomass source. Results. A specific biomass growth rate of biomass ranging from 0.04 to 1.7g per day was observed. The thiosulphate is biologically degraded by the biomass grown inside the reactor. The biodegradation rate of thiosulphate in the reactor varied from 0.02 to 0.80g per unit gram of biomass per day. A biodegradation rate of methanol in the reactor was observed in the range between 0.04 to 3.9g per unit gram of biomass per day. Bacterial biomass was grown as per the amount of methanol present inside the reactor. A maximum biomass yield coefficient of 0.7g biomass per gram of methanol was recorded. Thiosulphate was converted to sulphate that indirectly served as an electron acceptor for methanol degradation. Both degradation of methanol and thiosulphate in this experiment were in the range of the degradation rate shown for sulphate and organic compounds in other studies. Conclusion. Simultaneous removal of thiosulphate and methanol using an anaerobic bioreactor is promising and can be applied on an industrial scale. This finding is an important contribution to public health as it reduces the emission of toxic gas to the environment. Competing Interests. The authors declare no competing financial interests.
Show more [+] Less [-]Environmental Performance of Xylene, Hydrochloric Acid and Ammonia Solution During Pap Stain for Diagnosing Cervical Cancer Full text
2016
Jeel J. Moya-Salazar, MT | Victor A Rojas-Zumaran, MT
Background. Little importance has been placed on sustainability of the Papanicolaou (Pap) stain, the gold standard for the diagnosis of cervical cancer, for global environmental health. The standard Pap stain uses environmentally toxic and carcinogenic reactants such as xylene, hydrochloric acid and ammonia solution. Objectives. To eradicate the use of environmentally toxic and carcinogenic reactants through the validation of the Ecologic Papanicolaou (Eco-Pap) test. Methods. Reagent handling strategies were divided in three phases: used Harris' progressive hematoxilin, polychromatic solution and direct mounting that were analyzed by PEED-Cytology, Staining Quality Index (ICT) and the Bethesda system 2014. Results. A total of 52,319 Pap smears stained with Eco-Pap were admitted (ICT=0.91). Validation of the Eco-Pap versus conventional staining was optimal (Kappa =0.89) and the sensitivity and specificity of the method were 57% and 98%, respectively. Eco-Pap reduced the environmental contamination produced by xylene (66 liters), hydrochloric acid and ammonia (5.5 liters each) over nine months, and all diagnoses coincided with the cytological details. Conclusions. The Eco-Pap is an innovative method that transforms Pap testing into a sustainable and supportable technology.
Show more [+] Less [-]Analysis of cloudiness and solar radiation diurnal cycles for a better understanding of the forests greenness mean annual cycle in Central Africa. | Apport de l'analyse des cycles diurnes de nébulosité et de radiation solaire pour comprendre le cycle saisonnier moyen d'activité photosynthétique de la forêt en Afrique Centrale. Full text
2016
Philippon, Nathalie | de Lapparent, B. | Gond, V. | Bigot, S. | Brou, Yao Télesphore | Camberlin, Pierre | Cornu, G. | Dubreuil, Vincent | Martiny, Nadège | Morel, Béatrice | Moron, M. | Seze, G. | Laboratoire d'étude des transferts en hydrologie et environnement (LTHE) ; Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG) ; Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]) | Biens et services des écosystèmes forestiers tropicaux : l'enjeu du changement global (UPR BSEF) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad) | UMR 228 Espace-Dev, Espace pour le développement ; Institut de Recherche pour le Développement (IRD)-Université de Perpignan Via Domitia (UPVD)-Avignon Université (AU)-Université de La Réunion (UR)-Université de Montpellier (UM)-Université de Guyane (UG)-Université des Antilles (UA) | Biogéosciences [UMR 6282] (BGS) ; Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS) | Littoral, Environnement, Télédétection, Géomatique (LETG - Rennes) ; Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG) ; Université de Caen Normandie (UNICAEN) ; Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN) ; Université de Nantes (UN)-Université de Nantes (UN)-Université de Caen Normandie (UNICAEN) ; Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN) ; Université de Nantes (UN)-Université de Nantes (UN) | Energy Lab (ENERGY Lab) ; Université de La Réunion (UR) | Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE) ; Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Météorologie Dynamique (UMR 8539) (LMD) ; Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X) ; Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-École nationale des ponts et chaussées (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS-PSL ; École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL) | CNES (projet VEGREENE 2014-2015) | J.-M. Fallot, D. Joly & N. Bernard
6 pages | International audience | To better understand the Central Africa forests sensitivity toclimate variability, we jointly analyse the mean annual cycles of greenness, rainfall, cloudiness and solarradiation for the target region 0-5°N/12-19°E using high resolution satellite data. Our results demonstrate theimportance of the diurnal scale for understanding the mean annual cycles of rainfall, cloudiness and solarradiation and the way they shape those of forest greenness. They also suggest that whereas the March-Mayrainy season appears optimal for greenness especially because of favorable light conditions, water availabilityis the main controlling factor in December-January the main dry season and in February at the start of the firstvegetative season. Regarding the little dry season and the second rainy season (July-October) light availabilitymight be the main limiting factor to forests photosynthetic activity. | Afin de mieux comprendre la sensibilité de la forêt d'Afrique Centrale à la variabilité climatiqueactuelle, une analyse détaillée des cycles saisonniers moyens d'activité photosynthétique, de précipitations, decouverture nuageuse et de radiation solaire est menée pour la région 0-5°N/12-19°E, en s'appuyant sur desobservations satellites haute résolution spatiale et temporelle. Nos résultats montrent tout d'abord que l'échellediurne est une échelle clé pour comprendre les cycles saisonniers moyens de précipitations, nébulosité etradiation solaire, et comment ils façonnent celui d'activité photosynthétique des forêts. Ensuite, alors que lasaison mars-mai semble optimale pour l'activité photosynthétique des forêts en raison d'une bonne disponibilitéen lumière, la disponibilité en eau est le facteur de contrôle principal durant la grande saison sèche (décembrejanvier)et au démarrage de la 1ère saison végétative (février). De juillet à octobre, la plus faible disponibilitéen lumière pourrait être le principal facteur explicatif à la baisse de l'activité photosynthétique.
Show more [+] Less [-]Crisis management of chronic pollution: contaminated soil and human health Full text
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)
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