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981.
Sezen Saçan Aysun Uğur Uğur Sunlu Baha Büyükışık Mehmet Aksu F. Sanem Sunlu 《Environmental monitoring and assessment》2010,161(1-4):575-582
Bottom sediments reflect in general the relative contamination of a sea area. Therefore, a great deal of monitoring work has been dedicated to the analysis of bottom sediments. Izmir Bay is a very important pollution centre in Turkish Aegean coast region due to a densely populated community, industrial complex and maritime transportation, and there are many streams flowing into the bay that pass through a number of industrial and agricultural areas. It had received the majority of domestic and industrial wastewaters until the wastewater treatment plant was constructed. It is well known that sediments play an important role as reservoirs of a fraction of the pollution in aquatic systems. Therefore, sediment samples were collected monthly from three stations which are located in the inner part of the bay during the period January to December 2003. Temporal variations and seasonal changes on their 210Po and 210Pb contents were examined, and the activity concentrations of 210Po and 210Pb were found to vary from 43±6 to 132±12 and 27±5 to 91±9 Bq kg???1 dry wt, respectively. The highest values of those natural radionuclides were measured at Kar??yaka Station because of the current systems of the bay. Seasonally, the 210Pb levels were found to increase during the winter time for all the stations. 相似文献
982.
Victor F. Olaleye Emmanuel A. Oluyemi 《Environmental monitoring and assessment》2010,162(1-4):153-162
Effects of cement flue dust from Ewekoro cement Kilns were monitored at some aquatic receptor locations. High levels of total suspended particulates (TSPs) and atmospheric deposition rates (ADRs) were recorded within the factory compared to ancillary locations outside the factory. The TSP and ADR levels which were location dependent were significantly higher (P?<?0.05) during the dry periods than in the wet season. Irrespective of seasonal variations, the key elements in the emissions were Ca2?+? and Fe2?+?. The concentrations of Zn2?+?, Mn2?+? and Pb?+? which were trace elements were significantly higher (P?<?0.05) in the deposited than in the airborne particulates. The planktonic flora and fauna of the river systems draining the area were poor with 16 phytoplanktonic and nine zooplanktonic species. Numerically, the phytoplanktons were dominated by diatoms (Bacillariophyta) with Synedra sp. being the most abundant species. The zooplanktonic fauna dominated by rotifers had Lecane curvicornis as a regular occurrence in all the three catchment rivers. The physicochemical parameters assayed were significantly higher (P?<?0.05) in the factory effluent discharges than in water samples from each of the catchment rivers. Seasonal variations inclusive, HCO $_{3}^{-}$ , CO $_{3}^{2-}$ , Ca2?+? and Mg2?+? constituted the major ionic component of water samples analysed irrespective of location. Alaguntan River which receives effluents directly from the factory had significantly higher levels (P?<?0.05) of the assayed ions than the other two rivers draining the cement factory catchment areas. 相似文献
983.
J. Ruelas-Inzunza F. Páez-Osuna D. García-Flores 《Environmental monitoring and assessment》2010,162(1-4):251-263
With the aim of giving an overview on concentration and distribution of Cd, Cu, and Pb in fish from the coasts of Sinaloa state (SE Gulf of California), specimens with different feeding habits were collected in five locations. Sampling occurred between June 2003 and March 2004. Metal analyses on fish tissues were made by graphite furnace (Cd, Pb) and flame (Cu) atomic absorption spectrophotometry. Metal concentrations in tissues of carnivorous fish were grouped together and compared with corresponding concentrations in non-carnivorous fish; Cu and Pb levels were significantly (p?<?0.05) higher in liver of non-carnivorous species. Though no samples exceeded the maximum level set in international legislation for fish, from the perspective of the public health and considering the legal limits of fishery products for human consumption, Cu concentrations were exceeded (in tissues different from muscle) in four carnivorous and five non-carnivorous species according to the Australian legislation. In the case of Cd, two carnivorous species (Pomadasys leuciscus and Caulolatilus princeps) and one non-carnivorous species (Mugil cephalus), showed concentrations over the maximum level of 2 μg g???1 dry weight considered in the Mexican legislation. Considering average amounts of fish consumption in Mexico, daily mineral intake (DMI) values for Cu and percentage weekly intake (PWI) of Cd and Pb were estimated; none of the analyzed metals in edible portion of analyzed fish could be detrimental to humans. 相似文献
984.
Célia Anjos Alves Cátia Gonçalves Fátima Mirante Teresa Nunes Margarita Evtyugina Ana Sánchez de la Campa Ana C. Rocha Margarida Correia Marques 《Environmental monitoring and assessment》2010,168(1-4):321-337
PM10 continental rural background aerosols were collected during a summer field campaign (August–September 2006) at Lamas de Ôlo in the upper zone of the Alvão Natural Park, a mountain region of northern Portugal. In addition to the determination of the carbonaceous content by a thermal–optical method, the organic speciation of aerosols was performed by gas chromatography–mass spectrometry in an effort to evaluate photo-oxidation products of biogenic volatile organic compounds and other markers for source characterization. The detailed analysis revealed relatively high concentrations of polyols and short-chain dicarboxylic, tricarboxylic, hydroxycarboxylic, and oxocarboxylic acids, many of which are thought to be indicators of secondary aerosol formation, accounting for about 70% of global chromatographically resolved mass. Major photo-oxidation products of α- and β-pinene have been detected. The tracers for the photo-oxidation of isoprene comprise two diastereoisomeric 2-methyltetrols, C5-alkene triols, and 2-methylglyceric acid, which have only recently been elucidated. In addition, the occurrence of levoglucosan and other biomass combustion tracers indicates that the site was affected by wildfires. This source contributed to more than 80% of the organic carbon mass during a period of strong forest fire influence. 相似文献
985.
José Tomás Albergaria Maria da Conceição M. Alvim-Ferraz Maria Cristina F. Delerue-Matos 《Environmental monitoring and assessment》2010,171(1-4):171-180
The objectives of this work were: (1) to identify an isotherm model to relate the contaminant contents in the gas phase with those in the solid and non-aqueous liquid phases; (2) to develop a methodology for the estimation of the contaminant distribution in the different phases of the soil; and (3) to evaluate the influence of soil water content on the contaminant distribution in soil. For sandy soils with negligible contents of clay and natural organic matter, contaminated with benzene, toluene, ethylbenzene, xylene, trichloroethylene (TCE), and perchloroethylene (PCE), it was concluded that: (1) Freundlich’s model showed to be adequate to relate the contaminant contents in the gas phase with those in the solid and non-aqueous liquid phases; (2) the distribution of the contaminants in the different phases present in the soil could be estimated with differences lower than 10% for 83% of the cases; and (3) an increase of the soil water content led to a decrease of the amount of contaminant in the solid and non-aqueous liquid phases, increasing the amount in the other phases. 相似文献
986.
Nityananda Mondal Mayalagu Rajkumar Jun Sun Sourav Kundu P. S. Lyla Seyed Ajmal Khan Jean Paul Trilles 《Environmental monitoring and assessment》2010,171(1-4):471-486
The present study about the gammarid amphipods of Vellar and Uppanar estuaries was performed during two seasons (pre-monsoon and post-monsoon, 2005–2006), respectively, in nine habitats: five in the Vellar estuary and four in the Uppanar estuary. Amphipod samples were collected from sediments, oyster beds, seaweeds, sea grass, and mangroves. A total of 29 species of gammarid amphipods were collected in each area. The surface water temperature ranged from 16°C to 26°C, the salinity from 20 to 32 psu, and the pH between 7.5 and 8.3. Dissolved oxygen ranged from 5.3 to 7.8 ml/l. The maximum abundance of amphipods was observed during the pre-monsoon (July to September) in Vellar mangrove, and it was minimum during the pre-monsoon in Uppanar sea grass. It was found that several physicochemical factors, such as salinity, temperature, dissolved oxygen, pH, and the substrate have a marked effect on the distribution and the relative abundance of amphipods. The ranges of species diversity, richness, dominance, and evenness in the Vellar and Uppanar estuaries were 1.58–4.15, 1.82–5.29, 0–0.11, and 0.96–1, respectively. Using multivariate analyses, in each estuary, it was possible to identify different communities of amphipod species according to their habitats. 相似文献
987.
Mohamed F. Yassin 《Environmental science and pollution research international》2013,20(6):3975-3988
Due to heavy traffic emissions within an urban environment, air quality during the last decade becomes worse year by year and hazard to public health. In the present work, numerical modeling of flow and dispersion of gaseous emissions from vehicle exhaust in a street canyon were investigated under changes of the aspect ratio and wind direction. The three-dimensional flow and dispersion of gaseous pollutants were modeled using a computational fluid dynamics (CFD) model which was numerically solved using Reynolds-averaged Navier–Stokes (RANS) equations. The diffusion flow field in the atmospheric boundary layer within the street canyon was studied for different aspect ratios (W/H?=?1/2, 3/4, and 1) and wind directions (θ?=?90°, 112.5°, 135°, and 157.5°). The numerical models were validated against wind tunnel results to optimize the turbulence model. The numerical results agreed well with the wind tunnel results. The simulation demonstrated that the minimum concentration at the human respiration height within the street canyon was on the windward side for aspect ratios W/H?=?1/2 and 1 and wind directions θ?=?112.5°, 135°, and 157.5°. The pollutant concentration level decreases as the wind direction and aspect ratio increase. The wind velocity and turbulence intensity increase as the aspect ratio and wind direction increase. 相似文献
988.
A. Manoukian E. Quivet B. Temime-Roussel M. Nicolas F. Maupetit H. Wortham 《Environmental science and pollution research international》2013,20(7):4659-4670
Volatile organic compounds (VOCs) and particles emitted by incense sticks and candles combustion in an experimental room have been monitored on-line and continuously with a high time resolution using a state-of-the-art high sensitivity-proton transfer reaction-mass spectrometer (HS-PTR-MS) and a condensation particle counter (CPC), respectively. The VOC concentration–time profiles, i.e., an increase up to a maximum concentration immediately after the burning period followed by a decrease which returns to the initial concentration levels, were strongly influenced by the ventilation and surface interactions. The obtained kinetic data set allows establishing a qualitative correlation between the elimination rate constants of VOCs and their physicochemical properties such as vapor pressure and molecular weight. The emission of particles increased dramatically during the combustion, up to 9.1(±0.2)?×?104 and 22.0(±0.2)?×?104 part cm?3 for incenses and candles, respectively. The performed kinetic measurements highlight the temporal evolution of the exposure level and reveal the importance of ventilation and deposition to remove the particles in a few hours in indoor environments. 相似文献
989.
Trace element concentrations in soils along urbanization gradients in the city of Wien, Austria 总被引:3,自引:0,他引:3
Edina Simon Andreas Vidic Mihály Braun István Fábián Béla Tóthmérész 《Environmental science and pollution research international》2013,20(2):917-924
Urban soil is an important component of urban ecosystems. This study focuses on heavy metal contamination in soils of Wien (Austria) and results are compared to those for a few large European cities. We analysed the elemental contents of 96 samples of topsoil from urban, suburban and rural areas in Wien along a dynamic (floodplain forest) and a stable (oak–hornbeam forest) urbanization gradient. The following elements were quantified using ICP-OES technique: Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Pb, P, S and Zn. For heavy metals PI (pollution index) values were used to assess the level of pollution. The PI values indicated high level of pollution by Pb in the suburban and rural area of stable gradient and in the urban area of dynamic gradient; moderate level of pollution was indicated for Cd in the urban area of stable gradient. The level of pollution was moderate for Co in the suburban and rural area of the stable gradient, and for Cu in suburban area of stable gradient, and urban area of dynamic gradient. The pollution level of Zn was moderate in all areas. Urban soils, especially in urban parks and green areas may have a direct influence on human health. Thus, the elemental analysis of soil samples is one of the best ways to study the effects of urbanization. Our results indicated that the heavy metal contamination was higher in Wien than in a few large European cities. 相似文献
990.
Carlos Alberto A. de Almeida Carla G.B. Brenner Luciane Minetto Carlos A. Mallmann Ayrton F. Martins 《Chemosphere》2013
In this study, an analytical methodology was developed for the determination of psycho-active drugs in the treated effluent of the University Hospital at the Federal University of Santa Maria, RS – Brazil. Samples were collected from point A (Emergency) and point B (General effluent). The adopted methodology included a pre-concentration procedure involving the use of solid phase extraction and determination by liquid chromatography coupled to mass spectrometry. The limit of detection for bromazepam and lorazepam was 4.9 ± 1.0 ng L−1 and, for carbamazepine, clonazepam and diazepam was 6.1 ± 1.5 ng L−1. The limit of quantification was 30.0 ± 1.1 ng L−1, for bromazepam, clonazepam and lorazepam; for carbamazepine was 50.0 ± 1.8 ng L−1 and was 40.0 ± 1.0 ng L−1 for diazepam. The mean concentrations in the Emergency and General effluent treated currents were as follows: for bromazepam, 195 ± 6 ng L−1 and 137 ± 7 ng L−1; for carbamazepine, 590 ± 6 ng L−1 and 461 ± 10 ng L−1; for diazepam, 645 ± 1 ng L−1 and 571 ± 10 ng L−1; for lorazepam, 96 ± 7 ng L−1 and 42 ± 4 ng L−1; and for clonazepam, 134 ± 10 ng L−1 and 57 ± 10 ng L−1. A preliminary risk assessment was conducted: carbamazepine and diazepam require considerable attention owing to their environmental toxicity. The occurrence of these psychoactive-drugs and the environmental risks that they pose demonstrated the need for a more efficient treatment system. As far we are aware, there have been no comparable studies to this on the hazards of hospital effluents in Brazil, and very few that have carried out a risk assessment of psycho-active drugs in hospital effluent in general. 相似文献