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891.
The photodegradation and biotic transformation of the pharmaceuticals lidocaine (LDC), tramadol (TRA) and venlafaxine (VEN), and of the metabolites O-desmethyltramadol (ODT) and O-desmethylvenlafaxine (ODV) in the aquatic environmental have been investigated. Photodegradation experiments were carried out using a medium pressure Hg lamp (laboratory experiments) and natural sunlight (field experiments). Degradation of the target compounds followed a first-order kinetic model. Rates of direct photodegradation (light absorption by the compounds itself) at pH 6.9 were very low for all of the target analytes (?0.0059 h?1 using a Hg lamp and ?0.0027 h?1 using natural sunlight), while rates of indirect photodegradation (degradation of the compounds through photosensitizers) in river water at pH 7.5 were approximately 59 (LDC), 5 (TRA), 8 (VEN), 15 (ODT) and 13 times (ODV) higher than the rates obtained from the experiments in ultrapure water. The accelerated photodegradation of the target compounds in natural water is attributed mainly to the formation of hydroxyl radicals through photochemical reactions. Biotic (microbial) degradation of the target compounds in surface water has been shown to occur at very low rates (?0.00029 h?1). The half-life times determined from the field experiments were 31 (LDC), 73 (TRA), 51 (VEN), 21 (ODT) and 18 h (ODV) considering all possible mechanisms of degradation for the target compounds in river water (direct photodegradation, indirect photodegradation and biotic degradation). 相似文献
892.
Amphibians, particularly frogs and toads, are increasingly used as bioindicators of contaminant accumulation in pollution studies. We developed an analytical technique to analyse their elemental contents based on a small amount of toe bone samples. This method is environment-friendly as, unlike traditional methods, it is not necessary to kill animals during sampling. Using this technique, we explored the effects of urbanization on the elemental contents of toe bones. Bufo bufo specimens were collected from an urban and two rural ponds. The ratios of Ca and P at the ponds were: 20.5% Ca and 14.6% P at the urban pond and 30.4% and 29.6% Ca, 22.4% and 21.7% P at the rural ponds, respectively. For the other elements, the following percentage ratios were found: 0.7% B, 0.3% Mg and 0.06% Zn at the urban pond and 1.1% and 0.4% B, 0.4% Mg and 0.05% Zn at the rural ponds, respectively. Canonical discriminant analysis indicated the separation of the urban and the rural ponds based on the elemental concentrations of toe bones. Significant differences were found between the concentrations of Ca, P, Mg, B and Zn at the urban and the rural ponds (p?0.05). Anthropogenic activity was found to have effects on the elemental contents of toe bones in the urbanized area. Our study also demonstrated that the developed method was appropriate for the elemental analysis of small samples to assess the effects of urbanization. 相似文献
893.
Carballeira C Ramos-Gómez J Martín-Díaz ML DelValls TA Carballeira A 《Journal of environmental monitoring : JEM》2012,14(5):1305-1316
The increase in aquaculture activities in the last few decades has not been accompanied by a corresponding increase in environmental controls and regulations. In this context, the application of environmental monitoring plans (EMPs) has become necessary to assess the environmental impact associated with fish farming wastes. The objective of this review paper is to evaluate the suitability of experimental and analytical procedures as monitoring tools for inclusion in EMPs for intensive land-based marine fish farms (LBMFFs). The strong hydrodynamics and, in particular, the lack of sediment on the rocky coasts where LBMFFs are usually located, greatly limit the monitoring tools that can be used. We propose EMPs that employ a weight-of-evidence approach to evaluate: contamination, trophic and toxic effects, and ecological integrity. Laboratory tests, in situ bioassays and field surveys of local species are presented as key tools for assessing the impact of LBMFFs on ecosystems. The δ(15)N signal along a spatial gradient is proposed for evaluating exposure to contaminants. Trophic effects can be determined by growth of transplanted macro- and microalgae. Toxic effects can be evaluated by responses at different levels of biological organization, including biochemical and histological changes, physiological alterations and survival, in species from different trophic levels. Fouling tests and analysis of community structures are recommended for assessing ecological integrity. This review contributes to the development of environmental controls for intensive LBMFFs, and for other activities that discharge wastewater to rocky shores. 相似文献
894.
895.
Alves RR Vieira KS Santana GG Vieira WL Almeida WO Souto WM Montenegro PF Pezzuti JC 《Environmental monitoring and assessment》2012,184(11):6877-6901
For many millennia humans and reptiles have interacted, but the attitude of humans towards these animals has depended on culture, environment, and personal experience. At least 719 reptile species are known to occur in Brazil and about 11% of this fauna has been exploited for many different purposes, including bushmeat, leather, ornamental and magic/religious uses, and as folk medicines. Brazil can therefore serve as an interesting case study for better understanding reptile use by human societies, and the present paper catalogues some of the reptile species being used in Brazil and discusses implications for their conservation. A literature review indicated that 81 reptile species are culturally important in this country, with 47 (58%) species having multiple uses, 54 being used for medicinal purposes, 38 as food, 28 for ornamental or decorative purposes, 20 used in magic/religious practices, 18 as pets, and 40 are commonly killed when they come into contact with humans. Regarding their conservation status, 30 (37.5%) are included on State's Red List, Brazilian Red List or the IUCN Red List. There are many forms of interaction between reptiles and humans in Brazil-although most of them are quite negative in terms of wildlife conservation-which reinforces the importance of understanding such uses and interactions in the context of protecting reptiles in Brazil. A better understanding of the cultural, social, and traditional roles of these reptiles is fundamental to establishing management plans for their sustainable use. 相似文献
896.
Maria Aparecida Macêdo Silva Gilmara Fernandes Eça Danielle Felix Santos Alonso Góes Guimarães Michelle Coêlho Lima Marcelo Friederichs Landim de Souza 《Environmental monitoring and assessment》2013,185(7):5387-5399
Sampling was conducted monthly during a transition period between the dry and rainy seasons in order to evaluate the effectiveness of a municipal sewage treatment plant (STP) in eutrophication control. STP effluent and fluvial input data were also estimated. In the dry period, high concentrations of nutrients, chlorophyll a (up to 360 μg?L?1), and anoxia in bottom waters were observed in the upper portion of the estuary. Nitrate was scarce during the dry months, although high concentrations were observed at the river sources and the upper estuary. The N:P and Si:P molar ratios were usually below 16:1, and the Si:N ratio was higher than 1:1. The fluvial inputs were a greater source of nutrients to the estuary than the STP, but nutrient loading by these effluents were also important in contributing to the eutrophication of the upper estuarine zone, especially in the dry season when symptoms were more intense. 相似文献
897.
Inputs of heavy metals due to agrochemical use in tobacco fields in Brazil’s Southern Region 总被引:1,自引:0,他引:1
Hugo José Oliveira Zoffoli Nelson Moura Brasil do Amaral-Sobrinho Everaldo Zonta Marcus Vinícius Luisi Gracioso Marcon Alfredo Tolón-Becerra 《Environmental monitoring and assessment》2013,185(3):2423-2437
Only a few studies have assessed the joint incorporation of heavy metals into agricultural systems based on the range of agrochemicals used on a specific agricultural crop. This study was conducted to assess the heavy metals input through application of the main agrochemicals used in Brazilian tobacco fields. A total of 56 samples of different batches of 5 fertilizers, 3 substrates, 8 insecticides, 3 fungicides, 2 herbicides, and 1 growth regulator commonly used in the cultivation of tobacco in Brazil’s Southern Region were collected from 3 warehouses located in the States of Rio Grande do Sul, Santa Catarina, and Paraná. The total As, Cd, Co, Cr, Cu, Hg, Fe, Mn, Ni, Pb, and Zn content of the samples was then determined and compared with the regulations of different countries and information found in the available literature. The fertilizers were identified as the primary source of heavy metals among the agrochemicals used. Application of pesticides directly to the shoots of tobacco plants contributed very little to the supply of heavy metals. The agrochemicals used in Brazilian tobacco fields provide lower inputs of the main heavy metals that are nonessential for plants than those registered in the international literature for the majority of crop fields in different regions of the world. 相似文献
898.
Polycyclic aromatic hydrocarbons in surface water and bed sediments of the Hungarian upper section of the Danube River 总被引:1,自引:0,他引:1
Andrea Szabó Nagy Gábor Simon János Szabó István Vass 《Environmental monitoring and assessment》2013,185(6):4619-4631
This study was performed to elucidate the distribution, concentration trend and possible source of polycyclic aromatic hydrocarbons (PAHs) in surface water and bed sediments of the Hungarian upper section of the Danube River and the Moson Danube branch. A total of 217 samples (water and sediments) were collected from four different sampling sites in the period of 2001–2010 and analysed for the 16 priority US Environmental Protection Agency PAHs. Concentrations of total 16 PAHs (∑PAHs) in water samples ranged from 25 to 1,208 ng/L, which were predominated by two- and three-ring PAHs. The ∑PAH concentrations in sediments ranged from 8.3 to 1,202.5 ng/g dry weight. Four-ring PAHs including fluoranthene and pyrene were the dominant species in sediment samples. A selected number of concentration ratios of specific PAH compounds were calculated to evaluate the possible sources of PAH contamination. The ratios reflected a pattern of pyrogenic input as a major source of PAHs. The levels of PAHs determined were compared with other sections of the Danube and other regions of the world. 相似文献
899.
Alfredo Montero Alvarez Juan R. Estévez Alvarez Clístenes Williams Araújo do Nascimento Iván Pupo González Oscar Díaz Rizo Lázaro Lima Carzola Roberto Ayllón Torres Jorge Gómez Pascual 《Environmental monitoring and assessment》2017,189(1):28
Epiphytic lichens, collected from 119 sampling sites grown over “Roistonea Royal Palm” trees, were used to assess the spatial distribution pattern of lead (Pb) and identify possible pollution sources in Havana (Cuba). Lead concentrations in lichens and topsoils were determined by flame atomic absorption spectrophotometry and inductively coupled plasma (ICP) atomic emission spectrometry, respectively, while Pb in crude oils and gasoline samples were measured by ICP-time of flight mass spectrometry (ICP-ToF-MS). Lead isotopic ratios measurements for lichens, soils, and crude oils were obtained by ICP-ToF-MS. We found that enrichment factors (EF) reflected a moderate contamination for 71% of the samples (EF > 10). The 206Pb/207Pb ratio values for lichens ranged from 1.17 to 1.20 and were a mixture of natural radiogenic and industrial activities (e.g., crude oils and fire plants). The low concentration of Pb found in gasoline (<7.0 μg L?1) confirms the official statement that leaded gasoline is no longer used in Cuba. 相似文献
900.
Nikolett Czipa Gerda Diósi Clive Phillips Béla Kovács 《Environmental monitoring and assessment》2017,189(8):412
Detection of soil element deficiencies is time consuming, requiring a major commitment for field work and analysis. Bees concentrate some elements in their honey which could allow soil element concentrations to be predicted without having to take large numbers of soil samples. We measured 14 element concentrations in soil, sunflower, acacia flower and honey samples from two different regions of Hungary. Across sites, the elements with significant correlation coefficients between honey and soil concentrations, in descending order of probability, were Cu > Ba >Sr = Ni > Zn > Mn = Pb >As. Bioconcentration from soil to honey was similar for areas with acacia and sunflower flowers. In the macroelements, it was the greatest for K, S and P and least for Mg and Na, and in the microelements, greatest for B, then Zn, then Cu, then As, Mo and Sr and least for Fe, Ba, Mn and Pb. It is concluded that in acacia and sunflower-growing regions, honey can give an accurate estimate of soil element concentrations for Cu and Ba and provides relevant information for Sr, Ni, Zn, Mn, Pb and As. 相似文献