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101.
Numerous studies have shown the presence of pharmaceutically active compounds (PhACs) in different environmental compartments, for example, in surface water or wastewater ranging from nanograms per litre to micrograms per litre. Likewise, some recent studies have pointed to seasonal variability, thus indicating that PhAcs concentrations in the aquatic environment may depend on the time of year. This work intended to find out (1) whether Tagus fluvial and drinking water were polluted with different groups of PhACs and (2) if their concentrations differed between winter and summer seasons. From the 58 substances analysed, 41 were found belonging to the main therapeutic groups. Statistical differences were seen for antibacterials, antidepressants, anxiolytics, antiepileptics, and cardiovascular drugs, with higher concentrations being detected in winter than in summer. These results might indicate that the PhACs analysed in this study undergo lower environmental degradation in winter than in summer. In order to confirm these initial results, a continuous monitoring should be performed especially on those PhACs that either because of an elevated consumption or an intrinsic chemical persistence are poorly degraded during winter months due to low temperatures and solar irradiation. It is especially important to identify which of these specific PhACs are in order to recommend their substitution by equally effective and safe substances but also environmentally friendly.  相似文献   
102.
Industrial activity is one of the main sources of ambient pollution in developed countries. However, research analyzing its effect on birth outcomes is inconclusive. We analyzed the association between proximity of mother’s municipality of residence to industries from 24 different activity groups and risk of very (VPTB) and moderate (MPTB) preterm birth, very (VLBW) and moderate (MLBW) low birth weight, and small for gestational age (SGA) in Spain, 2004–2008. An ecological study was defined, and a “near vs. far” analysis (3.5 km threshold) was carried out using Hierarchical Bayesian models implemented via Integrated Nested Laplace Approximation. VPTB risk was higher for mothers living near pharmaceutical companies. Proximity to galvanization and hazardous waste management industries increased the risk of MPTB. Risk of VLBW was higher for mothers residing near pharmaceutical and non-hazardous or animal waste management industries. For MLBW many associations were found, being notable the proximity to mining, biocides and animal waste management plants. The strongest association for SGA was found with proximity to management animal waste plants. These results highlight the importance of further research on the relationship between proximity to industrial sites and the occurrence of adverse birth outcomes especially for the case of pharmaceutical and animal waste management activities.  相似文献   
103.
The purpose of this work is to investigate the behaviour and variability of oxidant levels (OX?=?NO2?+?O3), for the first time, in a rural coastal area in the southwest of the Iberian Peninsula, affected by several air masses types. Detailed database (built-up over the years 2008 to 2011, and containing around 500,000 data) from the Atmospheric Sounding Station “El Arenosillo” was used. The observed daily cycles of NO x and OX were influenced by air masses coming from industrial and urban area. It can be seen that the concentration of OX is made up of a NO x -independent ‘regional’ contribution (i.e. the O3 background), and a linearly NO x -dependent ‘local’ contribution from primary emissions, such as traffic. The local emission is very low in this area. Also, the regional contribution is similar to unpolluted sites and presents seasonal variation, being higher in May. However, our measurements showed that the proportion of OX in the form of NO2 increases with the increase in NO x concentration during the day. The higher proportion of NO2 observed at night must be due to the conversion of NO to NO2 by the NO?+?O3 reaction. With regards to the source of the local NO x -dependent contribution, it may be attributed to industrial emission, or the termolecular reaction 2NO?+?O2?=?2NO2, at high-NO x levels and stagnant air during several days. Finally, we estimated the photolysis rate of NO2, J NO2, an important key atmospheric reaction coupled with ozone. We also present surface plots of annual variation of the daily mean NO x and OX levels, which indicate that oxidants come from transport processes instead of local emissions associated as local photochemistry.  相似文献   
104.
The aim of this study was to compare and assess the dissolved concentrations of trace elements (As, Zn, Hg, Cd, Cr, Ni, Pb and Cu) in surface water of Marcal River before and after the red mud spill that occurred in Ajka, western Hungary, in October 2010. The caustic sludge flooded the surrounding settlements and polluted the nearby Torna Creek, which flows through the Marcal and Raba rivers into the Danube. A total of 92 surface water samples were collected from the Marcal River in the period of 2007–2012 and analysed for dissolved trace metal(loid)s by atomic absorption spectroscopy method. After the spill, the water management authority initially focused on acid dosing of surface waters to lower pH and was effective in lowering both pH and metal(loid) concentrations. Among the dissolved trace metal(loid)s, arsenic and nickel levels were moderately higher in the Marcal River 2 years since the spill compared to that observed in the pre-disaster period. The concentrations of dissolved trace metal(loid)s did not exceed the European water quality standards and the US Environmental Protection Agency aquatic life criteria values (excluding one sample for cadmium).  相似文献   
105.
Abstract

Land disposal of olive oil wastewater using it as a soil amendment requires a knowledge of the effects that its application may produce on the status of the mineral nutrients in the plant‐soil system. A pot experiment using calcareous soil was performed in a growth chamber to examine the effects of olive oil wastewater on the availability and postharvest soil extractability of K, Mg and Mn. The experiment included 6 treatments: two rates of olive oil wastewater, two mineral fertilizer treatments containing K (which supplied K in amounts equivalent to the K supplied by the olive oil wastewater treatments), a K‐free mineral fertilizer treatment, and a control. The pots were sown with ryegrass as the test plant, harvesting 3 times at intervals of one month. Olive oil wastewater has demonstrated a considerable capacity for supplying K that can be assimilated by the plant, tending in fact to surpass the mineral potassium fertilizer tested. The application of olive oil wastewater tends to reduce the concentration of Mg in the plant, similarly to the effect of adding mineral potassium fertilizer. An enhancement of Mn availability takes place in the soil amended with olive oil wastewater, which on occasion has produced Mn concentrations in plant that could be considered phytotoxic or at least excessive. After harvesting, we observed an increase in the amount of exchangeable K in soil with added industrial wastewater. However, these increases are lower than those in soil treated with mineral potassium fertilizer. The levels of exchangeable, carbonate‐bound, organic‐bound and residual Mg in soil were higher in treatments incorporating olive oil wastewater than in those with added mineral K, with the opposite tendency occurring in the amount of Fe‐Mn oxides‐bound Mg in soil. Treatments based on olive oil wastewater, especially in high doses, increased the amount of exchangeable and carbonate‐bound Mn in soil, in comparison with treatments adding mineral fertilizers with or without K. In contrast, the addition of industrial wastewater caused a drop in the amount of Fe‐Mn oxides‐bound and organic‐bound Mn in soil.  相似文献   
106.
The body of information presented in this paper is directed to scientists working in atmospheric dispersion research and model development. Two years of field measurements in the coastal area of Bilbao in northern Spain show that the diffusion behavior in this complex terrain can be classified into several well defined patterns, which correspond to certain meteorological conditions. The approach taken has been the systematic use of SO2 remote sensors (COSPEC) and ground level monitors in moving platforms which are used to follow and document the flow of the air mass. Results to date show that complex reentry cycles can occur and that synoptically different flows may be indistinguishable by wind sensors at ground level (affected by channeling), and yet result in totally different observed pollution levels by a fixed monitoring network (affected by topographical effects). These results are being used to parameterize the cause-effect relationships and guide the modeling efforts in this area of complex terrain.  相似文献   
107.
Within the changing fire regimes of Portugal, the relative importance of humans and climatic variability for regional fire statistics remains poorly understood. This work investigates the statistical relationship between temporal dynamics of fire events in Portugal and a set of socioeconomic, landscape, and climatic variables for the time periods of 1980–1990, 1991–2000, and extreme fires years. For 10 of 15 districts, it was possible to observe moderate shifts in the significance of fire drivers for the first two decadal periods. For others, pronounced changes of the significance of fire drivers were found across time. Results point toward a dynamic (perhaps highly non-linear) behavior of socioeconomic and landscape fire drivers, especially during the occurrence of extreme fire years of 2003 and 2005. At country level, population density alone explained 42% of the inter-annual and inter-district deviance in number of fires. At the same temporal and spatial scale, the explanatory power of temperature anomalies proved to explain 43% of area burnt. We highlight the necessity of including a broad set of socioeconomic and landscape fire drivers in order to account for potential significance shifts. In addition, although climate does trigger broad favorable fire conditions across Portugal mainland, socioeconomic and landscape factors proved to determine much of the complex fire patterns at a subnational scale.  相似文献   
108.
109.
Zaldívar JM  Baraibar J 《Chemosphere》2011,82(11):1547-1555
There is the need to integrate existing toxicity data in a coherent framework for extending their domain of applicability as well as their extrapolation potential. This integration would also reduce time and cost-consuming aspects of these tests and reduce animal usage. In this work, based on data extracted from literature, we have assessed the advantages that a dynamic biology-toxicant fate coupled model for Daphnia magna could provide when assessing toxicity data, in particular, the possibility to obtain from short-term (acute) toxicity test long-term (chronic) toxicity values taking into account the inherent variability of D. magna populations and the multiple sources of data. The results show that this approach overcomes some of the limitations of existing toxicity tests and that the prediction errors are considerably reduced when compared with the factor from 2 to 5 obtained using acute-to-chronic ratios.  相似文献   
110.
The study of extreme values and prediction of ozone data is an important topic of research when dealing with environmental problems. Classical extreme value theory is usually used in air-pollution studies. It consists in fitting a parametric generalised extreme value (GEV) distribution to a data set of extreme values, and using the estimated distribution to compute return levels and other quantities of interest. Here, we propose to estimate these values using nonparametric functional data methods. Functional data analysis is a relatively new statistical methodology that generally deals with data consisting of curves or multi-dimensional variables. In this paper, we use this technique, jointly with nonparametric curve estimation, to provide alternatives to the usual parametric statistical tools. The nonparametric estimators are applied to real samples of maximum ozone values obtained from several monitoring stations belonging to the Automatic Urban and Rural Network (AURN) in the UK. The results show that nonparametric estimators work satisfactorily, outperforming the behaviour of classical parametric estimators. Functional data analysis is also used to predict stratospheric ozone concentrations. We show an application, using the data set of mean monthly ozone concentrations in Arosa, Switzerland, and the results are compared with those obtained by classical time series (ARIMA) analysis.  相似文献   
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