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Risk of tuberculosis in high-rise and high density dwellings: An exploratory spatial analysis Texte intégral
2013
Lai, Poh C. | Low, Chien-Tat | Tse, Wing-Sze Cindy | Tsui, Chun-Kan | Sun Ra, | Hui, Pak-Kwan
Studies have shown that socioeconomic and environmental factors have direct/indirect influences on TB. This research focuses on TB prevalence of Hong Kong in relation to its compact urban development comprising of high-rise and high-density residential dwellings caused by rapid population growth and limited land resources. It has been postulated that occupants living on higher levels of a building would benefit from better ventilation and direct sunlight and thus less likely to contract infectious respiratory diseases. On the contrary, those on lower floors amid the dense clusters of high-rises are more susceptible to TB infection because of poorer air quality from street-level pollution and lesser exposure to direct sunlight. However, there have not been published studies to support these claims. As TB continues to threaten public health in Hong Kong, this study seeks to understand the effects of housing development on TB occurrences in an urban setting.
Afficher plus [+] Moins [-]Effects of plant species identity, diversity and soil fertility on biodegradation of phenanthrene in soil Texte intégral
2013
Oyelami, Ayodeji O. | Okere, Uchechukwu V. | Orwin, Kate H. | De Deyn, Gerlinde B. | Jones, K. C. (Kevin C.) | Semple, K. T. (Kirk T.)
The work presented in this paper investigated the effects of plant species composition, species diversity and soil fertility on biodegradation of 14C-phenanthrene in soil. The two soils used were of contrasting fertility, taken from long term unfertilised and fertilised grassland, showing differences in total nitrogen content (%N). Plant communities consisted of six different plant species: two grasses, two forbs, and two legume species, and ranged in species richness from 1 to 6. The degradation of 14C-phenanthrene was evaluated by measuring indigenous catabolic activity following the addition of the contaminant to soil using respirometry. Soil fertility was a driving factor in all aspects of 14C-phenanthrene degradation; lag phase, maximum rates and total extents of 14C-phenanthrene mineralisation were higher in improved soils compared to unimproved soils. Plant identity had a significant effect on the lag phase and extents of mineralisation. Soil fertility was the major influence also on abundance of microbial communities.
Afficher plus [+] Moins [-]Air Quality Standards for Particulate Matter (PM) at high altitude cities Texte intégral
2013
Bravo Alvarez, H. | Sosa Echeverria, R. | Sanchez Alvarez, P. | Krupa, S.
The Air Quality Standards for Particulate Matter (PM) at high altitude urban areas in different countries, must consider the pressure and temperature due to the effect that these parameters have on the breath volume.This paper shows the importance to correct Air Quality Standards for PM considering pressure and temperature at different altitudes. Specific factors were suggested to convert the information concerning PM, from local to standard conditions, and adjust the Air Quality Standards for different high altitudes cities. The correction factors ranged from: 1.03 for Santiago de Chile to 1.47 for El Alto Bolivia. Other cities in this study include: Mexico City, México; La Paz, Bolivia; Bogota, Cali and Medellin, Colombia; Quito, Ecuador and Cuzco, Peru.If these corrections are not considered, the atmospheric concentrations will be underestimated.
Afficher plus [+] Moins [-]Extreme precipitation appears a key driver of mercury transport from the watershed to Cottage Grove Reservoir, Oregon Texte intégral
2013
Curtis, Lawrence R. | Morgans, Donna L. | Thoms, Bryn | Villenueve, Daniel
An abandoned cinnabar mining and roasting site is in the major sub-basin of the watershed for Cottage Grove Reservoir, Oregon. Average surface sediment total mercury concentration in the river draining this sub-basin (0.61 ± 0.52 μg/g) was about ten-fold higher than three smaller tributaries to the reservoir. Total mercury in reservoir surface sediments averaged 1.66 ± 0.70 μg/g. Stratigraphy for two sediment cores indicated generally decreased reservoir mercury loading from 1963 to 2002 but two pronounced peaks in mercury deposition. Years of extreme precipitation immediately prior to these peaks at least partially explained them. Epaxial muscle total mercury concentrations of largemouth bass increased with body weight up to 2.5 μg/g. A gradient of mercury concentrations in soils from a 3.3 km diameter grid indicated condensation of mercury vapors from the mine site polluted the sub-basin.
Afficher plus [+] Moins [-]Assessing microbial carbon sources and potential PAH degradation using natural abundance 14C analysis Texte intégral
2013
Mahmoudi, Nagissa | Fulthorpe, Roberta R. | Burns, Leanne | Mancini, Silvia | Slater, Greg F.
Natural abundance 14C analysis was applied to PLFAs collected from an industrial site in southern Ontario in order to assess microbial carbon sources and potential PAH biodegradation in soils. Δ14C of microbial phospholipid fatty acids (PLFA) at the site ranged from +54‰ to −697‰. Comparison of these values to surrounding carbon sources found that microbial carbon sources were derived primarily from vegetation and/or natural organic matter present in the soils rather than PAHs. This study highlights that microbes are able to utilize almost all available pools of organic matter including older pools which are thought to contain recalcitrant compounds. Furthermore, it shows that even with the presence of an active microbial community, there may be little biodegradation of PAHs. This study illustrates challenges in assessing microbial activity in the environment and the advantage of using natural abundance 14C analysis as a tool to elucidate microbial carbon sources.
Afficher plus [+] Moins [-]Increased antioxidant response and capability to produce ROS in hemocytes of Pinna nobilis L. exposed to anthropogenic activity Texte intégral
2013
Sureda, Antoni | Natalotto, Antonino | Álvarez, Elvira | Deudero, Salud
Increased antioxidant response and capability to produce ROS in hemocytes of Pinna nobilis L. exposed to anthropogenic activity Texte intégral
2013
Sureda, Antoni | Natalotto, Antonino | Álvarez, Elvira | Deudero, Salud
Environmental pollutants exert immunotoxical effects on aquatic organisms. The aim was to determine the antioxidant response, markers of oxidative damage and reactive oxygen species production in hemocytes of Pinna nobilis, the largest endemic bivalve in the Mediterranean Sea, under anthropogenic pressure. P. nobilis individuals were collected from two locations along Mallorca Island waters attending to different degree of human impact and the hemocytes were obtained. Specimens from the impacted area showed increased activities of the antioxidant enzymes – catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase –, myeloperoxidase activity and reduced glutathione levels. No differences in oxidative damage markers – malondiahdehyde and carbonyl index – were evidenced between the pristine and polluted areas. Hemocytes from the polluted area presented increased capability to generate reactive oxygen species and nitrite/nitrate when activated. In conclusion, the human activities primed hemocytes for oxidative burst and increased the antioxidant mechanism without evidence of oxidative damage.
Afficher plus [+] Moins [-]Increased antioxidant response and capability to produce ROS in hemocytes of Pinna nobilis L. exposed to anthropogenic activiy Texte intégral
2013
Sureda, Antoni | Natalotto, Antonino | Álvarez, Elvira | Deudero, Salud
Environmental pollutants exert immunotoxical effects on aquatic organisms. The aim was to determine the antioxidant response, markers of oxidative damage and reactive oxygen species production in hemocytes of Pinna nobilis, the largest endemic bivalve in the Mediterranean Sea, under anthropogenic pressure. P. nobilis individuals were collected from two locations along Mallorca Island waters attending to different degree of human impact and the hemocytes were obtained. Specimens from the impacted area showed increased activities of the antioxidant enzymes - catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase -, myeloperoxidase activity and reduced glutathione levels. No differences in oxidative damage markers - malondiahdehyde and carbonyl index - were evidenced between the pristine and polluted areas. Hemocytes from the polluted area presented increased capability to generate reactive oxygen species and nitrite/nitrate when activated. In conclusion, the human activities primed hemocytes for oxidative burst and increased the antioxidant mechanism without evidence of oxidative damage.
Afficher plus [+] Moins [-]Terrestrial mosses as biomonitors of atmospheric POPs pollution: A review Texte intégral
2013
Harmens, H. | Foan, L. | Simon, V. | Mills, G.
Terrestrial mosses as biomonitors of atmospheric POPs pollution: A review Texte intégral
2013
Harmens, H. | Foan, L. | Simon, V. | Mills, G.
Worldwide there is concern about the continuing release of persistent organic pollutants (POPs) into the environment. In this study we review the application of mosses as biomonitors of atmospheric deposition of POPs. Examples in the literature show that mosses are suitable organisms to monitor spatial patterns and temporal trends of atmospheric concentrations or deposition of POPs. These examples include polycyclic aromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs), dioxins and furans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs). The majority of studies report on PAHs concentrations in mosses and relative few studies have been conducted on other POPs. So far, many studies have focused on spatial patterns around pollution sources or the concentration in mosses in remote areas such as the polar regions, as an indication of long-range transport of POPs. Very few studies have determined temporal trends or have directly related the concentrations in mosses with measured atmospheric concentrations and/or deposition fluxes.
Afficher plus [+] Moins [-]Terrestrial mosses as biomonitors of atmospheric POPs pollution: a review Texte intégral
2013
Harmens, Harry | Foan, Louise | Simon, Valérie | Mills, Gina | Centre for Ecology and Hydrology (UKCEH) ; Natural Environment Research Council (NERC) | Chimie Agro-Industrielle (CAI) ; Institut National de la Recherche Agronomique (INRA)-Ecole nationale supérieure des ingénieurs en arts chimiques et technologiques (ENSIACET) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT) | United Kingdom Department for Environment, Food and Rural Affairs (Defra) [AQ0816] ; UNECE (Trust Fund) ; Natural Environment Research Council (NERC)
International audience | Worldwide there is concern about the continuing release of persistent organic pollutants (POPs) into the environment. In this study we review the application of mosses as biomonitors of atmospheric deposition of POPs. Examples in the literature show that mosses are suitable organisms to monitor spatial patterns and temporal trends of atmospheric concentrations or deposition of POPs. These examples include polycyclic aromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs), dioxins and furans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs). The majority of studies report on PAHs concentrations in mosses and relative few studies have been conducted on other POPs. So far, many studies have focused on spatial patterns around pollution sources or the concentration in mosses in remote areas such as the polar regions, as an indication of long-range transport of POPs. Very few studies have determined temporal trends or have directly related the concentrations in mosses with measured atmospheric concentrations and/or deposition fluxes.
Afficher plus [+] Moins [-]Trophodynamics of inorganic pollutants in a wide-range feeder: The relevance of dietary inputs and biomagnification in the Yellow-legged gull (Larus michahellis) Texte intégral
2013
Ramos, Raúl | Ramirez, Francisco | Jover, Lluís
Trophodynamics of inorganic pollutants in a wide-range feeder: The relevance of dietary inputs and biomagnification in the Yellow-legged gull (Larus michahellis) Texte intégral
2013
Ramos, Raúl | Ramirez, Francisco | Jover, Lluís
The suitability of sentinel species to monitor environmental pollution is often hampered by an insufficient knowledge on pollutant trophodynamics. We simultaneously evaluated the influence of individuals' trophic position (as revealed by δ15N values) and dietary exploitation of particular systems (using δ13C and δ34S as proxies) on inorganic pollutant concentrations measured on fledglings' feathers of a wide-range feeder, the Yellow-legged Gull (Larus michahellis), sampled at four locations throughout the Western Mediterranean. Concentrations of total Hg and Se in fledgling feathers (2.43 ± 1.30 and 1.16 ± 0.43 μg/g, respectively) were under the threshold points for deleterious effects on seabirds. On the contrary, alarming Pb concentrations were found in one colony (mean: 1.57 ± 2.46 μg/g, range: 0.16–12.13). With the exception of Pb, pollutant concentrations were positively influenced by consumption of marine resources (as suggested by the positive relationship with δ34S values), whereas trophic position played a minor role in determining pollutant body burdens.
Afficher plus [+] Moins [-]Trophodynamics of inorganic pollutants in a wide-range feeder: The relevance of dietary inputs and biomagnification in the Yellow-legged gull (Larus michahellis) Texte intégral
2013
Ramos, Raül | Ramírez Benítez, Francisco | Jover, Lluís
The suitability of sentinel species to monitor environmental pollution is often hampered by an insufficient knowledge on pollutant trophodynamics. We simultaneously evaluated the influence of individuals' trophic position (as revealed by ο15N values) and dietary exploitation of particular systems (using ο13C and ο34S as proxies) on inorganic pollutant concentrations measured on fledglings' feathers of a wide-range feeder, the Yellow-legged Gull (Larus michahellis), sampled at four locations throughout the Western Mediterranean. Concentrations of total Hg and Se in fledgling feathers (2.43 ± 1.30 and 1.16 ± 0.43 οg/g, respectively) were under the threshold points for deleterious effects on seabirds. On the contrary, alarming Pb concentrations were found in one colony (mean: 1.57 ± 2.46 οg/g, range: 0.16-12.13). With the exception of Pb, pollutant concentrations were positively influenced by consumption of marine resources (as suggested by the positive relationship with ο34S values), whereas trophic position played a minor role in determining pollutant body burdens. © 2012 Published by Elsevier Ltd. | Peer Reviewed
Afficher plus [+] Moins [-]Role of arbuscular mycorrhizal fungus Rhizophagus custos in the dissipation of PAHs under root-organ culture conditions Texte intégral
2013
Aranda, Elisabet | Scervino, José Martín | Godoy, Patricia | Reina, Rocío | Ocampo, Juan Antonio | Wittich, Regina-Michaela | García-Romera, Inmaculada
Role of arbuscular mycorrhizal fungus Rhizophagus custos in the dissipation of PAHs under root-organ culture conditions Texte intégral
2013
Aranda, Elisabet | Scervino, José Martín | Godoy, Patricia | Reina, Rocío | Ocampo, Juan Antonio | Wittich, Regina-Michaela | García-Romera, Inmaculada
Polycyclic aromatic hydrocarbons (PAHs) are one of the most common contaminants in soil. Arbuscular mycorrhizal (AM) fungi make host plants resistant to pollutants. This study aims to evaluate the impact of anthracene, phenanthrene and dibenzothiophene on the AM fungus Rhizophagus custos, isolated from soil contaminated by heavy metals and PAHs, under monoxenic conditions. We found a high level of tolerance in R. custos to the presence of PAHs, especially in the case of anthracene, in which no negative effect on AM-colonized root dry weight (root yield) was observed, and also a decrease in the formation of anthraquinone was detected. Increased PAH dissipation in the mycorrhizal root culture medium was observed; however, dissipation was affected by the level of concentration and the specific PAH, which lead us to a better understanding of the possible contribution of AM fungi, and in particular R. custos, to pollutant removal.
Afficher plus [+] Moins [-]Role of arbuscular mycorrhizal fungus Rhizophagus custos in the dissipation of PAHs under root-organ culture conditions Texte intégral
2013
Aranda, Elisabet | Scervino, Jose Martin | Godoy, Patricia | Reina, Rocío | Ocampo, Juan Antonio | Wittich, Regina Michaela | García Romera, Inmaculada
Polycyclic aromatic hydrocarbons (PAHs) are one of the most common contaminants in soil. Arbuscular mycorrhizal (AM) fungi make host plants resistant to pollutants. This study aims to evaluate the impact of anthracene, phenanthrene and dibenzothiophene on the AM fungus Rhizophagus custos, isolated from soil contaminated by heavy metals and PAHs, under monoxenic conditions. We found a high level of tolerance in R. custos to the presence of PAHs, especially in the case of anthracene, in which no negative effect on AM-colonized root dry weight (root yield) was observed, and also a decrease in the formation of anthraquinone was detected. Increased PAH dissipation in the mycorrhizal root culture medium was observed; however, dissipation was affected by the level of concentration and the specific PAH, which lead us to a better understanding of the possible contribution of AM fungi, and in particular R. custos, to pollutant removal. | Fil: Aranda, Elisabet. Consejo Superior de Investigaciones Científicas; España | Fil: Scervino, Jose Martin. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; Argentina | Fil: Godoy, Patricia. Consejo Superior de Investigaciones Científicas; España | Fil: Reina, Rocío. Consejo Superior de Investigaciones Científicas; España | Fil: Ocampo, Juan Antonio. Consejo Superior de Investigaciones Científicas; España | Fil: Wittich, Regina Michaela. Consejo Superior de Investigaciones Científicas; España | Fil: García Romera, Inmaculada. Consejo Superior de Investigaciones Científicas; España
Afficher plus [+] Moins [-]Does selective serotonin reuptake inhibitor (SSRI) fluoxetine affects mussel Mytilus galloprovincialis? Texte intégral
2013
Gonzalez-Rey, Maria | Bebianno, Maria João
Does selective serotonin reuptake inhibitor (SSRI) fluoxetine affects mussel Mytilus galloprovincialis? Texte intégral
2013
Gonzalez-Rey, Maria | Bebianno, Maria João
Fluoxetine (FLX) the active pharmaceutical ingredient (API) in Prozac® is a widely prescribed psychoactive drug which ubiquitous occurrence in the aquatic environment is associated to a poor removal rate in waste-water treatment plant (WWTP) systems. This API acts as a selective serotonin reuptake inhibitor (SSRI) frequently reported to cause disrupting effects in non-target species. The objective of this study includes a multibiomarker response evaluation on mussel Mytilus galloprovincialis during two weeks exposure to 75 ng L−1 FLX assessing antioxidant enzymes activities – superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST); lipid peroxidation (LPO), acetylcholinesterase (AChE) neurotoxic response and endocrine disruption through alkali-labile phosphates (ALP) indirect measurement of vitellogenin-like proteins. Results show transient tissue-specific enzymatic responses and damage affecting mostly mussel gills. However, the clear ALP levels inhibition throughout time in both sex-differentiated gonads gives evidence to FLX reinforced action as an endocrine disruptor rather than an oxidative or neurotoxic inducer.
Afficher plus [+] Moins [-]Does selective serotonin reuptake inhibitor (SSRI) fluoxetine affects mussel Mytilus galloprovincialis? Texte intégral
2013
Gonzalez-Rey, Maria | Bebianno, Maria João
Fluoxetine (FLX) the active pharmaceutical ingredient (API) in Prozac(®) is a widely prescribed psychoactive drug which ubiquitous occurrence in the aquatic environment is associated to a poor removal rate in waste-water treatment plant (WWTP) systems. This API acts as a selective serotonin reuptake inhibitor (SSRI) frequently reported to cause disrupting effects in non-target species. The objective of this study includes a multibiomarker response evaluation on mussel Mytilus galloprovincialis during two weeks exposure to 75 ng L(-1) FLX assessing antioxidant enzymes activities--superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST); lipid peroxidation (LPO), acetylcholinesterase (AChE) neurotoxic response and endocrine disruption through alkali-labile phosphates (ALP) indirect measurement of vitellogenin-like proteins. Results show transient tissue-specific enzymatic responses and damage affecting mostly mussel gills. However, the clear ALP levels inhibition throughout time in both sex-differentiated gonads gives evidence to FLX reinforced action as an endocrine disruptor rather than an oxidative or neurotoxic inducer. | info:eu-repo/semantics/publishedVersion
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