Уточнить поиск
Результаты 261-270 из 1,956
Does selective serotonin reuptake inhibitor (SSRI) fluoxetine affects mussel Mytilus galloprovincialis? Полный текст
2013
Gonzalez-Rey, Maria | Bebianno, Maria João
Does selective serotonin reuptake inhibitor (SSRI) fluoxetine affects mussel Mytilus galloprovincialis? Полный текст
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.
Показать больше [+] Меньше [-]Does selective serotonin reuptake inhibitor (SSRI) fluoxetine affects mussel Mytilus galloprovincialis? Полный текст
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
Показать больше [+] Меньше [-]In vitro assessment of thyroid hormone disrupting activities in drinking water sources along the Yangtze River Полный текст
2013
Hu, Xinxin | Shi, Wei | Zhang, Fengxian | Cao, Fu | Hu, Guanjiu | Hao, Yingqun | Wei, Si | Wang, Xinru | Yu, Hongxia
The thyroid hormone disrupting activities of drinking water sources from the lower reaches of Yangtze River were examined using a reporter gene assay based on African green monkey kidney fibroblast (CV-1) cells. None of the eleven tested samples showed thyroid receptor (TR) agonist activity. Nine water samples exhibited TR antagonist activities with the equivalents referring to Di-n-butyl phthalate (DNBP) (TR antagonist activity equivalents, ATR-EQ50s) ranging from 6.92 × 101 to 2.85 × 102 μg DNBP/L. The ATR-EQ50s and TR antagonist equivalent ranges (ATR-EQ30–80 ranges) for TR antagonist activities indicated that the water sample from site WX-8 posed the greatest health risks. The ATR-EQ80s of the water samples ranging from 1.56 × 103 to 6.14 × 103 μg DNBP/L were higher than the NOEC of DNBP. The results from instrumental analysis showed that DNBP might be responsible for the TR antagonist activities in these water samples. Water sources along Yangtze River had thyroid hormone disrupting potential.
Показать больше [+] Меньше [-]Retrofitting impervious urban infrastructure with green technology for rainfall-runoff restoration, indirect reuse and pollution load reduction Полный текст
2013
Sansalone, John | Raje, Saurabh | Kertesz, Ruben | Maccarone, Kerrilynn | Seltzer, Karl | Siminari, Michele | Simms, Peter | Wood, Brandon
The built environs alter hydrology and water resource chemistry. Florida is subject to nutrient criteria and is promulgating “no-net-load-increase” criteria for runoff and constituents (nutrients and particulate matter, PM). With such criteria, green infrastructure, hydrologic restoration, indirect reuse and source control are potential design solutions. The study simulates runoff and constituent load control through urban source area re-design to provide long-term “no-net-load-increases”. A long-term continuous simulation of pre- and post-development response for an existing surface parking facility is quantified. Retrofits include a biofiltration area reactor (BAR) for hydrologic and denitrification control. A linear infiltration reactor (LIR) of cementitious permeable pavement (CPP) provides infiltration, adsorption and filtration. Pavement cleaning provided source control. Simulation of climate and source area data indicates re-design achieves “no-net-load-increases” at lower costs compared to standard construction. The retrofit system yields lower cost per nutrient load treated compared to Best Management Practices (BMPs).
Показать больше [+] Меньше [-]Complexation with dissolved organic matter and mobility control of heavy metals in the rhizosphere of hyperaccumulator Sedum alfredii Полный текст
2013
Li, Tingqiang | Tao, Qi | Liang, Chengfeng | Shohag, M.J.I. | Yang, Xiaoe | Sparks, Donald L.
The complexation of Zn, Cd and Pb with dissolved organic matter (DOM) in the rhizosphere of hyperaccumulating ecotype (HE) and a non-hyperaccumulating ecotype (NHE) of Sedum alfredii was measured using resin equilibration method. After the growth of HE S. alfredii, the rhizosphere soil pH was reduced by 0.27–0.33 units, due to enhanced DOM derived from root exudation. For both ecotypes of S. alfredii, the fraction of free metal as a percentage of soluble metal varied from 22.1 to 42.5% for Zn2+, from 8.1 to 15.5% for Cd2+, and from 4.5 to 10.4% for Pb2+. Resin equilibration experiment results indicated that HE–DOM had greater ability to form complexes with Zn, Cd and Pb than NHE–DOM, Visual MINTEQ model gave excellent predictions of the complexation of Zn and Cd by DOM (R2 > 0.97). DOM in the rhizosphere of HE S. alfredii could significantly increase metal mobility through the formation of soluble DOM-metal complexes.
Показать больше [+] Меньше [-]Risk of tuberculosis in high-rise and high density dwellings: An exploratory spatial analysis Полный текст
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.
Показать больше [+] Меньше [-]Effects of plant species identity, diversity and soil fertility on biodegradation of phenanthrene in soil Полный текст
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.
Показать больше [+] Меньше [-]Air Quality Standards for Particulate Matter (PM) at high altitude cities Полный текст
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.
Показать больше [+] Меньше [-]Extreme precipitation appears a key driver of mercury transport from the watershed to Cottage Grove Reservoir, Oregon Полный текст
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.
Показать больше [+] Меньше [-]Influence of age, sex and breeding status on mercury accumulation patterns in the wandering albatross Diomedea exulans Полный текст
2013
Tavares, S. | Xavier, J.C. | Phillips, R.A. | Pereira, M.E. | Pardal, M.A.
Influence of age, sex and breeding status on mercury accumulation patterns in the wandering albatross Diomedea exulans Полный текст
2013
Tavares, S. | Xavier, J.C. | Phillips, R.A. | Pereira, M.E. | Pardal, M.A.
Although mercury bio-amplifies through the food chain and accumulates in top predators, mercury concentrations in tissues of the wandering albatross are greater than in any other vertebrate, including closely related species. In order to explore the alternative explanations for this pattern, we measured total mercury concentrations in feathers, plasma and blood cells of wandering albatrosses of known age, sex and breeding status sampled at South Georgia. Mercury concentrations were low in feathers and blood components of chicks, and higher in the feathers of young pre-breeders than in feathers or blood of older pre-breeders and breeding adults. There was no effect of sex on mercury concentrations in the feathers of pre-breeders or breeding adults, whereas levels were significantly higher in blood cells of breeding females than males. The high feather mercury concentrations of young pre-breeders compared with older birds suggest an increase in moult frequency as birds approach maturity.
Показать больше [+] Меньше [-]Influence of age, sex and breeding status on mercury accumulation patterns in the wandering albatross Diomedea exulans Полный текст
2013
Tavares, S. | Xavier, J. C. | Phillips, R. A. | Pereira, M. E. | Pardal, M. A.
Although mercury bio-amplifies through the food chain and accumulates in top predators, mercury concentrations in tissues of the wandering albatross are greater than in any other vertebrate, including closely related species. In order to explore the alternative explanations for this pattern, we measured total mercury concentrations in feathers, plasma and blood cells of wandering albatrosses of known age, sex and breeding status sampled at South Georgia. Mercury concentrations were low in feathers and blood components of chicks, and higher in the feathers of young pre-breeders than in feathers or blood of older pre-breeders and breeding adults. There was no effect of sex on mercury concentrations in the feathers of pre-breeders or breeding adults, whereas levels were significantly higher in blood cells of breeding females than males. The high feather mercury concentrations of young pre-breeders compared with older birds suggest an increase in moult frequency as birds approach maturity. | This work was supported by the Portuguese Foundation for the Science and Technology (FCT) through a PhD grant to Sílvia Tavares (SFRH/BD/48908/2008),co-funded by the European Social Fund and Portuguese Government National Funds, and through the project POLAR. This paper represents a contribution to the British Antarctic Survey Ecosystems Programme, the national program PROPOLAR and the international programs of ICED and SCAR AnT-ERA. | published
Показать больше [+] Меньше [-]Assessing microbial carbon sources and potential PAH degradation using natural abundance 14C analysis Полный текст
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.
Показать больше [+] Меньше [-]