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1.
Use of the BCR three-step sequential extraction procedure for the study of the partitioning of Cd, Pb and Zn in various soil samples 总被引：1，自引：0，他引：1
A slightly modified three-step sequential extraction procedure proposed by the Community Bureau of Reference (BCR) for analysis
of sediments was successfully applied to soil samples. Contaminated soil samples from the lead and zinc mining area in the
Mezica valley (Slovenia) and natural soils from a non-industrial area were analysed. The total concentrations of Cd, Pb and
Zn and their concentrations in fractions after extraction were determined by flame or electrothermal atomic absorption spectrometry
(FAAS, ETAAS). Total metal concentrations in natural soils ranged from 0.3 to 2.6 mg kg-1 for Cd, from 20 to 45 mg kg-1 for Pb and from 70 to 140 mg kg-1 for Zn, while these concentrations ranged from 0.5 to 35 mg kg-1 for Cd, from 200 to 10000 mg kg-1 for Pb and from 140 to 1500 mg kg-1 for Zn in soils from contaminated areas. The results of the partitioning study applying the slightly modified BCR three-step
extraction procedure indicate that Cd, Pb and Zn in natural soils prevails mostly in sparingly soluble fractions. Cd in natural
soils is bound mainly to Fe and Mn oxides and hydroxides, Pb to organic matter, sulphides and silicates, while Zn is predominantly
bound to silicates. In contaminated soils, Cd, Pb and Zn are distributed between the easily and sparingly soluble fractions.
Due to the high total Cd, Pb and Zn concentrations in contaminated soil close to the smelter, ! and their high proportions
in the easily soluble fraction (80% of Cd, 50% of Pb and 70% of Zn), the soil around smelters represents an environmental
hazard. 相似文献
2.
Dušan Jankov Dušanka Inđić Petar Kljajić Radmila Almaši Goran Andrić Slavica Vuković Mila Grahovac 《Journal of pest science》2013,86(2):211-216
The aim of the study was to investigate how various types of storage facilities with, e.g., concrete, metal, and plywood surfaces interfere with the activity of different insecticide formulations used for rice weevil Sitophilus oryzae (L.) control: malathion (EC), pirimiphos-methyl (EC), and lambda-cyhalothrin (CS and WP). Initial and residual efficacy were determined in the laboratory. Knockdown data for the initial effects were processed by probit analysis and presented as knockdown time (KDT) parameters with kdt-p lines. Delayed effects were shown as knockdown efficacy (%) determined after 24 h of weevils’ contact with 7-, 14-, 30-, 60-, 90-, 120-, 150-, and 180-day-old deposits on each surface. Malathion (EC) and pirimiphos-methyl (EC) showed the highest initial knockdown efficacy on metal, while it was 3.6 (3.4)- and 4.4 (3.3)-fold lower on concrete and plywood, respectively. Lambda-cyhalothrin (CS and WP) showed the highest initial efficacy on concrete, and slightly lower (1.3 and 2.4) fold on metal and plywood, respectively. Both formulations of lambda-cyhalothrin and malathion on metal, as well as pirimiphos-methyl on plywood were 100 % efficient against S. oryzae 180 days after the treatment. Delayed efficacy of both formulations of lambda-cyhalothrin decreased on plywood after 120 days, and after 180 days the efficacy was 55 %. All insecticides, except lambda-cyhalothrin (CS), expressed low knockdown efficacy on concrete, while the deposit of lambda-cyhalothrin (CS) on concrete was 100 % efficient during 90 days, and after 120, 150, and 180 days the efficacy was 83, 65, and 17 %, respectively. 相似文献
3.
Milica Marković Tea Zuliani Snežana Belanović Simić Zorana Mataruga Olga Kostić Snežana Jarić Janja Vidmar Radmila Milačič Janez Ščančar Miroslava Mitrović Pavle Pavlović 《Journal of Soils and Sediments》2018,18(12):3404-3414
Purpose
Riparian zone contamination is a growing problem for several European catchments due to high anthropogenic pressures. This study investigates As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in the Sava River riparian zone, characterized by wide agricultural areas, various geological substrates, and different types of industrial pollution. The accumulation and mobility of these elements were studied because they are listed as priority substances in the Water Framework Directive and environmental objectives for surface waters.Materials and methods
Sampling was performed during the sampling campaign of the EU 7th FW-funded GLOBAQUA project in September 2015 during a low-water event. Soil samples were collected along the Sava River at 12 selected sampling sites, from a depth of 0–30 cm, at a distance of 10–15 m from the river bank. The extent of pollution was estimated by determining total and readily soluble element concentrations in the soils. Potential ecological risk and the source of the selected elements in the soils was determined using the enrichment factor (EF), potential ecological risk index (RI), and statistical methods such as the principal component analysis (PCA) and multiple linear regression analysis (MLRA).Results and discussion
This study showed that concentrations of the selected elements increase along the Sava. In terms of origin, PCA and MLRA indicated that Cr and Ni in soils are predominantly lithogenic, while As, Cd, Pb, and Zn are both lithogenic and anthropogenic (ore deposits, industry, and agriculture). PCA singled out Cu since its origin in soil is most probably from specific point-source pollution. EF was generally minor to moderate for most of the examined elements, apart from Cu, for which the EF was significant at one sampling site. Overall ecological risk (RI) fell within the low-risk category for most sites, apart from Belgrade sampling site (BEO), where high total Cd content affected individual and overall ecological risk indicators, indicating Cd could represent a considerable ecological risk for the downstream riparian zone.Conclusions
At downstream sites, there was a noticeable increase in PTE content, with Cd, Cr, Ni, and Zn exceeding the proposed threshold values for European soils, indicating rising contamination in riparian soils. In terms of the ecological risk, only Cd could pose a potential ecological threat for the downstream riparian zone.4.
Petrujkić B Samanc H Adamović M Stojić V Petrujkić T Grdović S Sefer D Marković R 《The Japanese journal of veterinary research》2010,58(3-4):171-177
This trial was designed in order to evaluate the incidence of subacute rumen acidosis (SARA) during early lactation and to investigate the possibilities for its prevention by use of a buffering mineral mixture. On the beginning of the trial it was found that the pH value of rumen fluid in 4 animals was lower than normal (pH < 6.0) and that 20% of animals have had SARA. The control and the experimental group of cows were fed the same meal with exception of concentrated feed which in the experimental group contained the mineral mix with buffering activity in amount of 1%. Continuous addition of buffering mineral mixture in the amount of 1% in concentrated feed for early lactation cows successfully prevents SARA formation and leads to increased milk production, as well as increased milk fat and protein content. 相似文献
5.
Occasionally, multiple names are given to the same gene/protein. When this happens, different names can be used in subsequent publications, for example in different research areas, sometimes with little or no awareness that the same entity known under a different name may have a major role in another field of science. Recent reports about the protein p11 presented findings that this protein, commonly known as S100A10, may play a crucial role in depression and antidepressant treatment mechanisms. One set of data showed an increased expression of this protein in the brain of mice treated with antidepressants. P11/S100A10 is only one of several S100 proteins expressed in the brain. Interestingly, it has been previously noted that antidepressant treatment increases the brain content of another S100 protein, S100B. It appears that up-regulating the brain content of various S100 proteins might be a common feature of antidepressants. In cells coexpressing S100A10 and S100B, these proteins may interact and exert opposite regulatory roles. Nevertheless, S100A10 is predominantly expressed in certain types of neurons whereas S100B is more abundant in glia. Thus, an interplay among multiple members of the S100 proteins might be important in determining the region and cell specificity of antidepressant mechanisms. Calling the p11 protein by its other name, S100A10, may prompt more investigators from different fields to participate in this new direction of neurobiological research. 相似文献
6.
Agnes šÖmen Joksič Sidney A. Katz Milena Horvat Radmila Milačič 《Water, air, and soil pollution》2005,162(1-4):265-283
Potential uses of dredged sediments have raised questions about leaching of contaminants from such material once transported to other locations and exposed to other environments. In order to estimate leachable, i.e. available fractions of chemical elements in such materials, a number of analytical protocols were proposed, of which none is internationally accepted as a standard procedure. As a consequence, comparability of the results obtained by different protocols in various laboratories is difficult to demonstrate. In the present study some commonly used protocols including a leaching test with (i) seawater, following the modified German Standard Method (DIN), (ii) a single extraction with 25% acetic acid, following the method proposed by the United Nations Environment Programme (UNEP), and (iii) a three-step sequential extraction, following both the original and the modified protocols of the Standards, Measurements and Testing Programme (formerly Community Bureau of Reference – BCR), were performed for assessing the availability of lead, zinc, nickel and copper leachable from dredged marine sediments. A comparison of the results obtained by the different protocols indicated that the single extraction with acetic acid is a reliable simplified technique and allows more rapid evaluations of dredged areas of coastal lagoons in the Northern Adriatic. This procedure provides information on the potentially bioavailable portion of metals. 相似文献
7.
Zupančič Marija Bukovec Nataša Milačič Radmila Ščančar Janez 《Water, air, and soil pollution》2004,154(1-4):57-69
This paper reports the results of the treatment of polychlorinatedbiphenyl (PCB) contaminated sandy soils (100 mg kg-1 Aroclor 1242) with the Fenton advanced oxidation process (AOP). The results obtained in the various assays permitted the optimization of conditions as follows: 5% H2O2; 100 ppm of Fe3+; and a ratio of sandy soil mass/volume of oxidizing solution (m/V) of 1/3 g mL-1. In addition, these tests established the need for agitation and dispensed with the need for heat. The results obtained confirm that the oxidation process occurs in solid phase (on the PCBs adsorbed to soil particles), producing 98% elimination of the original PCB structure and 82% dechlorination, all within a reaction time of 72 hr. The degree of elimination was found to be dependent on the level of congener chlorination and the process displays a pseudo first order kinetics. In addition, the Fenton chemical oxidation process may be complemented by subsequent aerobic biological degradation which, after 15 days, produces 72% mineralization of the products generated during the chemical oxidation process. 相似文献
8.
Radmila Stikic Djordje Glamoclija Mirjana Demin Biljana Vucelic-Radovic Zorica Jovanovic Dusanka Milojkovic-Opsenica Sven-Erik Jacobsen Mirjana Milovanovic 《Journal of Cereal Science》2012
Quinoa is an Andean seed crop of many potential uses. In 2009 a field trial was carried out to explore the potential for quinoa growing in climatic conditions of South Eastern Europe. Even under rainfed conditions, without fertilization, a seed yield as high as 1.721 t ha−1 was obtained. Seed quality was remarkably good, with protein content ranging from 15.16 to 17.41 % on a dry weight basis, depending on whether seeds were processed. Amino acid and mineral composition revealed the potential of quinoa seeds as a valuable ingredient in the preparation of highly nutritious foods. Quinoa seeds had higher contents of most essential amino acids, especially lysine, than wheat flour. Dehulled quinoa seeds, devoid of saponins, were included into wheat bread formulations, with up to 20%, which resulted in a positive effect on the rheological characteristics of dough. Furthermore, protein content in bread was increased by around 2%. Sensory characteristics of breads were excellent also at the 20% supplementation level. The study of bread supplemented with quinoa seeds could enable the development of a range of new baking products with enhanced nutritional value. 相似文献
9.
Larvae (metacestodes) of tapeworms of the cyclophyllidean family Gryporhynchidae (previously included in the Dilepididae) occur in different internal organs of fresh- and brackish water fish (110 fish species of 27 families in 12 orders reported), which serve as the second intermediate hosts. The species composition, spectrum of fish hosts, sites of infection, and geographical distribution of gryporhynchids recorded from fish are reviewed here on the basis of literary data and examination of extensive material from helminthological collections. Metacestodes of the following genera have been found in fish: Amirthalingamia Bray, 1974 (1 species), Ascodilepis Guildal, 1960 (1), Cyclustera Fuhrmann, 1901 (4), Dendrouterina Fuhrmann, 1912 (1), Glossocercus Chandler, 1935 (3), Neogryporhynchus Baer et Bona, 1960 (1), Paradilepis Hsü, 1935 (5), Parvitaenia Burt, 1940 (2), and Valipora Linton, 1927 (3). However, most published records concern only three species, namely Neogryporhynchus cheilancristrotus (Wedl, 1855) from the intestinal lumen, Paradilepis scolecina (Rudolphi, 1819) from the liver and mesenteries, and Valipora campylancristrota (Wedl, 1855) from the gall bladder of cyprinids and other fish in the Palaearctic Region. Data on other species as well as reports from other regions are very scarce and almost no information is available from Australia, tropical Asia and South America. A recent study of gryporhynchid metacestodes from Mexico (Scholz and Salgado-Maldonado 2001), which reported 13 species, suggested that they may be more common than indicated by records in the literature. Although only a few cases of pathogenic influence of larvae on fish hosts have been reported, the veterinary importance of gryporhynchids remains to be assessed on the basis of more detailed studies. The data available indicate a strict host and site specificity of some species whereas others occur in a wide spectrum of fish hosts and are not strictly site-specific. Evaluation of Paradilepis larvae from the liver of salmonid fish from British Columbia, Canada, identified as P. simoni Rausch, 1949 by Ching (1982), has shown that they probably belong to two species, P. simoni and P. rugovaginosus Freeman, 1954. Metacestodes of the latter species and those of Cyclustera magna (Baer, 1959) from the intestinal wall of Tilapia zillii (Gervais) from Kenya are reported from fish for the first time. 相似文献
10.
Sediment analysis is very important ininvestigations of the heavy metal burden in theenvironment. In the present work various digestion andextraction procedures were evaluated in order toassess the extent of contamination with heavy metalsin sediments from the Moste hydroelectric reservoir.Total acid dissolution, aqua regia digestion andacetic acid extraction procedures were applied tosamples. Zn, Cd, Pb, Co, Ni, Cu and Cr were determinedby flame or electrothermal atomic absorptionspectrometry (FAAS, ETAAS) under optimized measurementconditions. A comparison of total acid dissolutionincluding hydrofluoric acid (HF) treatment and theaqua regia soluble fraction was made to estimatethe applicability of aqua regia digestion inanalysis of total metal concentrations in sediments.In general, good agreement of the results was observedfor Co, Pb, Cu and Zn, however for Cr, Ni and Cdsignificantly lower results were obtained in the aqua regia soluble fraction. In addition, an extraction procedure using 25% v/v acetic acid wasapplied for estimation of the extent of contaminationwith heavy metals originating from anthropogenicactivities. The results indicate that the sedimentsupstream of the reservoir are not contaminated, whilethe sediments from the hydroelectric reservoir showsa significant anthropogenic input of Ni, Zn and Pb,which corresponds well with pollution sources. 相似文献