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Jolanta Skowroń Lidia Zapór Katarzyna Miranowicz-Dzierżawska 《International journal of occupational safety and ergonomics》2013,19(1):107-116
The acute-toxic-class method (ATC) is an alternative to the classical LD50 test. Four substances were tested with an ATC testing procedure. The results were compared with LD50 data obtained from the literature. Great importance was attached to the observations of toxic signs following administration. The results of this study have shown that the ATC method allows allocation to toxicity classes in the same manner as on the basis of the classical LD50 tests. The ATC method uses fewer animals and yields the same information on toxic signs. Introducing the ATC method into the quality system allows estimating the acute oral toxicity of chemicals according to the Organisation for Economic Cooperation and Development (OECD; OECD, 1992, 1996). 相似文献
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Lizhu Wang Kevin Wehrly James E. Breck Lidia Szabo Kraft 《Environmental management》2010,46(3):471-483
Assessment of lake impairment status and identification of threats’ type and source is essential for protection of intact,
enhancement of modified, and restoration of impaired lakes. For regions in which large numbers of lakes occur, such assessment
has usually been done for only small fractions of lakes due to resource and time limitation. This study describes a process
for assessing lake impairment status and identifying which human disturbances have the greatest impact on each lake for all
lakes that are 2 ha or larger in the state of Michigan using readily available, georeferenced natural and human disturbance
databases. In-lake indicators of impairment are available for only a small subset of lakes in Michigan. Using statistical
relationships between the in-lake indicators and landscape natural and human-induced measures from the subset lakes, we assessed
the likely human impairment condition of lakes for which in-lake indicator data were unavailable using landscape natural and
human disturbance measures. Approximately 92% of lakes in Michigan were identified as being least to marginally impacted and
about 8% were moderately to heavily impacted by landscape human disturbances. Among lakes that were heavily impacted, more
inline lakes (92%) were impacted by human disturbances than disconnected (6%) or headwater lakes (2%). More small lakes were
impacted than medium to large lakes. For inline lakes, 90% of the heavily impacted lakes were less than 40 ha, 10% were between
40 and 405 ha, and 1% was greater than 405 ha. For disconnected and headwater lakes, all of the heavily impacted lakes were
less than 40 ha. Among the anthropogenic disturbances that contributed the most to lake disturbance index scores, nutrient
yields and farm animal density affected the highest number of lakes, agricultural land use affected a moderate number of lakes,
and point-source pollution and road measures affected least number of lakes. Our process for assessing lake condition represents
a significant advantage over other routinely used methods. It permits the evaluation of lake condition across large regions
and yields an overall disturbance index that is a physicochemical and biological indicator weighted sum of multiple disturbance
factors. The robustness of our approach can be improved with increased availability of high-resolution disturbance datasets. 相似文献
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A number of important rivers of Romania were investigated for pharmaceutical and antifungal residues. In a post target approach analysis, a single-stage, high-resolution mass spectrometry was successfully applied for the screening of 43 pharmaceuticals and fungicides in water, using U-HPLC-Exactive Orbitrap MS at 50,000 full width at half maximum resolution. Detection was based on accurate masses and retention times. The study confirmed the presence of pharmaceuticals and antifungals such as diclofenac, sulfamethoxazole, carbamazepine, trimethoprim, thiabendazole, and clotrimazole, in water. Diclofenac and carbamazepine were the most frequently detected (eight samples); concentrations ranged from 5 to 50 ng L?1. Low concentrations of griseofulvin were detected in the Prut River. Further monitoring studies should be carried out in order to fill the gaps of knowledge concerning the presence of pharmaceutical residues in Romanian water environment and to improve public understanding regarding the environmental risk of pharmaceutical contamination. 相似文献
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Emissions from the combustion of biomass and fossil fuels are a significant source of particulate matter (PM) in ambient outdoor and/or indoor air. It is important to quantify PM emissions from combustion sources for regulatory and control purposes in relation to air quality. In this paper, we review emission factors for several types of important combustion sources: road transport, industrial facilities, small household combustion devices, environmental tobacco smoke, and vegetation burning. We also review current methods for measuring particle physical characteristics (mass and number concentrations) and principles of methodologies for measuring emission factors. The emission factors can be measured on a fuel-mass basis and/or a task basis. Fuel-mass based emission factors (e.g., g/kg of fuel) can be readily used for the development of emission inventories when the amount of fuels consumed are known. Task-based emission factors (g/mile driven, g/MJ generated) are more appropriate when used to conduct comparisons of air pollution potentials of different combustion devices. Finally, we discuss major shortcomings and limitations of current methods for measuring particle emissions and present recommendations for development of future measurement techniques. 相似文献
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The paper presents the application of the hyphenated technique - high-performance liquid chromatography with atomic absorption spectrometry detection with hydride generation (HPLC-HG-AAS) - in the determinations of inorganic forms of arsenic: As(III) and As(V) in the exchangeable fraction of flood deposits. The separation of analytical signals of the determined arsenic forms was obtained using an ion-exchange column in a chromatographic system with the atomic absorption spectrometer as a detector, at the determination limits of 5 ng g−1 for As(III) and 10 ng g−1 for As(V). Flood deposits were collected after big flood event in valley of the Warta river which took place in summer 2010. Samples of overbank deposits were taken in Poznań agglomeration and vicinity (NW Poland). The results of determinations of arsenic forms in the exchangeable fraction of flood deposits allowed indication of a hypothetical path of deposits migration transported by a river during flood and environmental threats posed by their deposition by flood. 相似文献
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Lidia Pino Cristina ItalianoAntonio Vit Concetto FabianoVincenzo Recupero 《环境科学学报(英文版)》2016,28(10):138-150
Sorbents for CO_2 capture have been prepared by wet impregnation of a commercial active carbon(Ketjen-black, Akzo Nobel) with two CO_2-philic compounds, polyethylenimine(PEI)and tetraethylenepentamine(TEPA), respectively. The effects of amine amount(from 10 to70 wt.%), CO_2 concentration in the feed, sorption temperature and gas hourly space velocity on the CO_2 capture performance have been investigated. The sorption capacity has been evaluated using the breakthrough method, with a fixed bed reactor equipped with on line gas chromatograph. The samples have been characterized by N_2 adsorption–desorption,scanning electron microscopy and energy dispersive X-ray(SEM/EDX). A promising CO_2 sorption capacity of 6.90 mmol/gsorbenthas been obtained with 70 wt.% of supported TEPA at 70℃ under a stream containing 80 vol% of CO_2. Sorption tests, carried out with simulated biogas compositions(CH_4/CO_2mixtures), have revealed an appreciable CO_2 separation selectivity; stable performance was maintained for 20 adsorption–desorption cycles. 相似文献
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