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21.
Atmospheric particulate matter (PM) abundance, mass size distribution (MSD) and chemical composition are parameters relevant for human health effects. The MSD and phase state of semivolatile organic pollutants were determined at various polluted sites in addition to the PM composition and MSD. The distribution pattern of pollutants varied from side to side in correspondence to main particle sources and PM composition. Levels of particle-associated polycyclic aromatic hydrocarbons (PAHs) were 1–30 ng m?3 (corresponding to 15–35 % of the total, i.e., gas and particulate phase concentrations), of polychlorinated biphenyls (PCBs) were 2–11 pg m?3 (4–26 % of the total) and of DDT compounds were 2–12 pg m?3 (4–23 % of the total). The PM associated amounts of other organochlorine pesticides were too low for quantification. The organics were preferentially found associated with particles <0.45 μm of aerodynamic equivalent diameter. The mass fractions associated with sub-micrometer particles (PM0.95) were 73–90 %, 34–71 % and 36–81 % for PAHs, PCBs and DDT compounds, respectively. The finest particles fraction had the highest aerosol surface concentration (6.3–29.7)×10?6 cm?1 (44–70 % of the surface concentration of all size fractions). The data set was used to test gas-particle partitioning models for semivolatile organics for the first time in terms of the organics' MSD and size-dependent PM composition. The results of this study prove that at the various sites particles with diverse size, matrix composition, amount of contaminants and toxicological effects occur. Legislative regulation based on gravimetric determination of PM mass can clearly be insufficient for assessment.  相似文献   
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There is an increasing attempt in the world to determine the exposures of children to environmental chemicals. To analyze the genotoxic effect of air pollution, micronucleus (MN) assay was carried out in buccal epithelial cells (BECs) of children living in an urban city of Turkey. Children from two schools at urban-traffic and suburban sites were investigated in summer and winter seasons for the determination of BEC-MN frequency (per mille) and frequency of BEC with MN (per mille). The same children were also recruited for lung function measurements within a MATRA project (“Together Towards Clean Air in Eskisehir and Iskenderun”) Measured NO2 and SO2 concentrations did not exceed the European Union (EU) limit levels either in urban-traffic or suburban regions. Higher O3 concentrations were measured in the suburban site especially in the summer period. Particulate matter (PM2.5 and PM10) levels which did not differ statistically between two regions were above the EU limits in general. Although BEC-MN frequencies of children living in the suburban sites were higher in general, the difference between two regions was not significant either in the summer or winter periods. BEC-MN frequencies of the urban-traffic children were found to be significantly higher in summer period (mean ± SD, 2.68?±?1.99) when compared to winter period (1.64?±?1.59; p?=?0.004). On the other hand, no seasonality was observed for the suburban children. Similar results have been obtained in the BEC frequency with MN in our study. In summer, BEC-MN frequencies were significantly increased with the decrease in pulmonary function levels based on forced expiratory flow between 25 and 75 % of vital capacity (FEF25–75 %) levels (p?<?0.05). As a conclusion, children living in urban-traffic and suburban areas in the city of Eski?ehir exhibited similar genotoxicity. Seasonal variation in genotoxicity may be interpreted as relatively high ozone levels and increasing time spent at outdoors in the summer.  相似文献   
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The purpose of this study was an experimental investigation and a statistical evaluation of the influence of various additives in feed mixtures of broiler chickens on fatty acids content and their ratio in breast and thigh muscles. First feed additive consisted of narasin, nicarbasin and salinomycin sodium, and other five additives were of phytogenic origin. In vivo experiment was realized on the poultry experimental station with deep litter breeding system. A total of 300 one-day-old hybrid chickens Cobb 500 divided into six groups were used for the experiment. The experimental period was divided into four phases, i.e. Starter, Grower 1, Grower 2 and Final, according to the application of commercial feed mixture of soy cereal type. Additive substances used in feed mixtures were different for each group. Basic feed mixtures were equal for all groups. Fatty acid profile of breast and thigh muscles was measured by the method of FT IR Nicolet 6700. Investigated additive substances in the feed mixtures did not have statistically significant effect on fatty acid content and omega-6/omega-3 polyunsaturated fatty acid (PUFA) ratio in breast and thigh muscles. Strong statistically significant relation between omega-6 PUFAs and total PUFAs were proved by experiment. A relation between omega-3 PUFAs and total PUFAs was found only in the group with Biocitro additive.  相似文献   
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Environmental Science and Pollution Research - In this work, a multi-class analytical method for determination of 22 frequently used pharmaceuticals was developed and validated. Analytes were from...  相似文献   
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The aim of this study is to investigate how the presence of Cu influences tebuconazole (Teb) sorption onto contrasting soil types and two important constituents of the soil sorption complex: hydrated Fe oxide and humic substances. Tebuconazole was used in commercial form and as an analytical-grade chemical at different Teb/Cu molar ratios (1:4, 1:1, 4:1, and Teb alone). Increased Cu concentrations had a positive effect on tebuconazole sorption onto most soils and humic substances, probably as a result of Cu?Teb tertiary complexes on the soil surfaces. Tebuconazole sorption increased in the following order of different Teb/Cu ratios 1:4?>?1:1?>?4:1?>?without Cu addition, with the only exception for the Leptosol and ferrihydrite. The highest K f value was observed for humic substances followed by ferrihydrite, the Cambisol, the Arenosol, and the Leptosol. The sorption of analytical-grade tebuconazole onto all matrices was lower, but the addition of Cu supported again tebuconazole sorption. The Teb/Cu ratio with the highest Cu addition (1:4) exhibited the highest K f values in all matrices with the exception of ferrihydrite. The differences in tebuconazole sorption can be attributed to the additives present in the commercial product. This work proved the importance of soil characteristics and composition of the commercially available pesticides together with the presence of Cu on the behavior of tebuconazole in soils.  相似文献   
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The role of metals in urinary stone formation has already been studied in several publications. Moreover, urinary calculi can also be used for assessing exposure of humans to minor and trace elements in addition to other biological matrices, for example, blood, urine, or hair. However, using urinary calculi for biomonitoring of trace elements is limited by the association of elements with certain types of minerals. In this work, 614 samples of urinary calculi were subjected to mineralogical and elemental analysis. Inductively coupled plasma mass spectrometry and thermo-oxidation cold vapor atomic absorption spectrometry were used for the determination of major, minor, and trace elements. Infrared spectroscopy was used for mineralogical analysis, and additionally, it was also employed in the calculation of mineralogical composition, based on quantification of major elements and stoichiometry. Results demonstrate the applicability of such an approach in investigating associations of minor and trace elements with mineralogical constituents of stones, especially in low concentrations, where traditional methods of mineralogical analysis are not capable of quantifying mineral content reliably. The main result of this study is the confirmation of association of several elements with struvite (K, Rb) and with calcium phosphate minerals, here calculated as hydroxylapatite (Na, Zn, Sr, Ba, Pb). Phosphates were proved as the most important metal-bearing minerals in urinary calculi. Moreover, a significantly different content was also observed for Fe, Zr, Mo, Cu, Cd, Se, Sn, and Hg in investigated groups of minerals. Examination of such associations is essential, and critical analysis of mineral constituents should precede any comparison of element content among various groups of samples.  相似文献   
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The mobility (fractionation) of rare earth elements (REEs) and their possible impacts on ecosystems are still relatively unknown. Soil samples were collected from two sites in central Serbia, an unpolluted mountain region (site 1) and a forest near a city (site 2). In order to investigate REE fractions (acid-soluble/exchangeable, reducible, oxidizable, and residual) in soils, BCR sequential extraction was performed. Additionally, the content of REEs was also determined in stipes and caps of the mushroom Macrolepiota procera, growing in the observed sites. Sc, Y, and lanthanide contents were determined by inductively coupled plasma mass spectrometry (ICP-MS), and results were subjected to multivariate data analysis. Application of pattern recognition technique revealed the existence of two distinguished clusters belonging to different geographical sites and determined by greater levels of Sc, Y, and lanthanides in Go? soil compared to Trstenik soil. Additionally, PCA analysis showed that REEs in soil were concentrated in two groups: the first consisted of elements belonging to light REEs and the second contained heavy REEs. These results suggest that the distribution of REEs in soils could indicate the geographical origin and type of soil. The bioconcentration factors and translocation factors for each REE were also calculated. This study provides baseline data on the rare earth element levels in the wild edible mushroom M. procera, growing in Serbia. In terms of bioconcentration and bioexclusion concept, Sc, Y, and REEs were bioexcluded in M. procera for both studied sites.

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As large carnivores recover throughout Europe, their distribution needs to be studied to determine their conservation status and assess the potential for human-carnivore conflicts. However, efficient monitoring of many large carnivore species is challenging due to their rarity, elusive behavior, and large home ranges. Their monitoring can include opportunistic sightings from citizens in addition to designed surveys. Two types of detection errors may occur in such monitoring schemes: false negatives and false positives. False-negative detections can be accounted for in species distribution models (SDMs) that deal with imperfect detection. False-positive detections, due to species misidentification, have rarely been accounted for in SDMs. Generally, researchers use ad hoc data-filtering methods to discard ambiguous observations prior to analysis. These practices may discard valuable ecological information on the distribution of a species. We investigated the costs and benefits of including data types that may include false positives rather than discarding them for SDMs of large carnivores. We used a dynamic occupancy model that simultaneously accounts for false negatives and positives to jointly analyze data that included both unambiguous detections and ambiguous detections. We used simulations to compare the performances of our model with a model fitted on unambiguous data only. We tested the 2 models in 4 scenarios in which parameters that control false-positive detections and true detections varied. We applied our model to data from the monitoring of the Eurasian lynx (Lynx lynx) in the European Alps. The addition of ambiguous detections increased the precision of parameter estimates. For the Eurasian lynx, incorporating ambiguous detections produced more precise estimates of the ecological parameters and revealed additional occupied sites in areas where the species is likely expanding. Overall, we found that ambiguous data should be considered when studying the distribution of large carnivores through the use of dynamic occupancy models that account for misidentification.  相似文献   
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