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591.
Bilau M De Henauw S Schroijen C Bruckers L Hond ED Koppen G Matthys C Van De Mieroop E Keune H Baeyens W Nelen V Van Larebeke N Willems JL Schoeters G 《Environment international》2009,35(1):9-13
Dioxin-like activity was measured in the serum of 1425 Flemish men and women via the CALUX assay. The adults, aged between 50 and 65 years, participated in a large biomonitoring program, executed by the Flemish Center of Expertise for Environment and Health between 2002 and 2006. Within the context of this biomonitoring program also dietary intake of dioxin-like contaminants was assessed through a food frequency questionnaire. The relation between the estimated dietary intake and the dioxin-like activity in serum was evaluated using multivariate analyses: a logistic model was performed on the total population, while a linear regression analysis was done on the subsample with quantifiable dioxin activity levels in serum. Region, gender, age, BMI, smoking status, as well as dietary habits were entered in the model, with dioxin level as an outcome estimate. Both the logistic and linear model confirmed the contribution of dietary intake to the dioxin activity measured in serum. Also BMI and region were found to be associated with dioxin activity levels. 相似文献
592.
Influence of pH on the sonolysis of ciprofloxacin: Biodegradability, ecotoxicity and antibiotic activity of its degradation products 总被引:3,自引:0,他引:3
Evelien De Bel Jo Dewulf Bavo De Witte Herman Van Langenhove Colin Janssen 《Chemosphere》2009,77(2):291-295
The presence of antibiotics in the aquatic environment has raised concerns due to the potential risk for the emergence or persistence of antibiotic resistance. Antibiotics are often poorly degraded in conventional wastewater treatment plants. In this study, sonolysis at 520 kHz and 92 W L−1 was used for the degradation of the fluoroquinolone antibiotic ciprofloxacin. In a first experiment at pH 7, 57% of the ciprofloxacin (15 mg L−1) was degraded after 120 min of ultrasonic irradiation at 25 °C. pH proved to be an important parameter determining the degradation rate, since the pseudo first order degradation constant increased almost fourfold when comparing treatment at pH 7 (0.0058 min−1) and pH 10 (0.0069 min−1) with that at pH 3 (0.021 min−1). This effect can be attributed to the degree of protonation of the ciprofloxacin molecule. The BOD/COD ratio of the solutions, which is a measure for their biodegradability, increased from 0.06 to 0.60, 0.17, and 0.18 after 120 min of irradiation depending on the pH (3, 7, and 10, respectively). The solution treated at pH 3 can even be considered readily biodegradable (BOD/COD > 0.4). The antibiotic activity against Escherichia coli (G−) and Bacillus coagulans (G+) of the treated solutions also reduced after sonolysis. The highest decrease was again found when irradiated at pH 3. In contrast, ecotoxicity of the solutions to the alga Pseudokirchneriella subcapitata increased 3- to 10-fold after 20 min of treatment, suggesting the formation of toxic degradation products. The toxicity slowly diminished during further treatment. 相似文献
593.
Joachim Maes Jo Vliegen Karen Van de Vel Stijn Janssen Felix Deutsch Koen De Ridder Clemens Mensink 《Atmospheric environment (Oxford, England : 1994)》2009,43(6):1246-1254
CORINAIR atmospheric emission inventories are frequently used input data for air quality models with a domain situated in Europe. In CORINAIR emission inventories, sources are broken down over 11 major source categories. This paper presents spatial surrogates for the disaggregation of CORINAIR atmospheric emission inventories for input of air pollutants and particulate matter to grid or polygon based air quality model domains inside Europe. The basis for the disaggregation model was the CLC2000 land cover data to which statistical weights were added. Weights were population census data for residential emissions, employment statistics for agricultural and industrial area emissions, livestock statistics for ammonia emissions and annual aircraft movements for emissions realized by air transport. Additional road and off-road network information was used to disaggregate emissions realized by traffic. A comparison of top down produced emission estimates with spatially resolved national emission data for The Netherlands and the United Kingdom gave confidence in the present spatial surrogates as a tool for the top down production of atmospheric emission maps. Explained variance at a spatial resolution of 5 km was >70% for CO, NMVOC and NOx, >60% for PM10 and almost 50% for SO2. 相似文献
594.
Rognvald Boyd Sarah-Jane Barnes Patrice De Caritat Victor A. Chekushin Victor A. Melezhik Clemens Reimann Michael L. Zientek 《Atmospheric environment (Oxford, England : 1994)》2009,43(7):1474-1480
Published estimates for base metal emissions from the copper–nickel industry on the Kola Peninsula are re-examined in the light of (a) chemical data on the composition of the ores; (b) official emission figures for 1994; and (c) modelled emissions based on dry and wet deposition estimates derived from data for snow and rain samples collected in 1994. The modelled emissions, official emission figures and chemical data are mutually compatible for Ni, Cu and Co and show that previously published figures underestimated the emissions of the major elements, Ni and Cu (though within the same order of magnitude) and overestimated the emissions of As, Pb, Sb and Zn by up to several orders of magnitude, in some cases exceeding the calculated total input to the plants. Published estimates have neglected information on the nature and chemistry of the ores processed in metallurgical industries in the Noril'sk area of Siberia and the Urals. Revised emission estimates for 1994, using knowledge of the chemistry of the ores, are proposed: taken with published information on total emissions up to 2000 these data give an indication of emission levels in more recent years. 相似文献
595.
Rodrigo A. Medellín ‡ Miguel Equihua † and Miguel A. Amin 《Conservation biology》2000,14(6):1666-1675
Abstract: Evaluating the degree of disturbance of any region to determine its relative importance for conservation purposes requires procedures that are relatively inexpensive and that yield accurate results fast. Because bats are abundant, diverse, and easy to sample, especially in the Neotropical rainforest, they fulfill several of the requirements of indicator species as identified in the literature. For 10 months we sampled bat communities in the Selva Lacandona in Chiapas, Mexico, at 15 sites representing five habitats. We also measured 10 variables representing vegetation structure and diversity at each site. With fuzzy-set techniques we produced a gradient classification of disturbance for the 15 sites based on the vegetation data. We explored the relationship between vegetation conditions, described as the membership degrees in the construct "fuzzy forest set" (the complementary fuzzy set of "disturbance"), and four bat community variables. Bat species richness, number of rare bat species, and the bat diversity index were positively correlated with the vegetation scores, and relative abundance of the most abundant bat species was negatively correlated with vegetation scores. A high number of phyllostomine species in a community is a good indicator of low levels of disturbance. Although a single indicator group will probably not be sufficient for decision-making processes in conservation, evaluating bat populations may be a good first step in assessing an area's conservation value, especially in rainforest regions. 相似文献
596.
Monitoring Mammal Populations in Costa Rican Protected Areas under Different Hunting Restrictions 总被引:8,自引:0,他引:8
Abstract: It is necessary to assess whether the management of protected areas is achieving the objectives set for them. In particular, changes and trends in wildlife populations should be documented. We compared the 1990 abundance of mammals in two Costa Rican protected areas, Corcovado National Park (CNP) and Golfo Dulce Forest Reserve (GDFR), with similar environmental characteristics but different hunting restrictions and levels of protection. We also monitored the abundance of mammals in CNP over a 4-year period. We also devised an inexpensive method of monitoring tropical rainforest mammal populations in a timely and efficient manner. The method is based on the use of mammal track records and arboreal mammal sightings and requires little effort. With this method 20 mammal species were recorded at CNP and 15 at GDFR. Species were consistently less abundant in GDFR than in CNP, principally those species preferred by hunters. Species were grouped according to whether or not they are used as food and whether they are locally or globally threatened or not threatened. The abundance of all these groups of species in GDFR was 6–28% the abundance in CNP. During 1990–1994, overall mammal abundance in CNP remained relatively stable, but there was considerable variability among species. As a group, both species used for food and globally threatened species declined in abundance during that period in CNP. The abundance of all groups of species declined from 1992 to 1994, coinciding with a reduction in hunting vigilance at CNP. Evidence suggests that the main factor differentiating the abundance of mammals in the two protected areas, and at CNP during the study period, was the level of hunting. Golfo Dulce Forest Reserve seems to be achieving only partial success in protecting wildlife, whereas Corcovado National Park seems to be considerably more effective, although not entirely successful. 相似文献
597.
硝酸盐氮,亚硝酸盐氮总量紫外吸收快速测定 总被引:1,自引:0,他引:1
水体中尤其是海水中硝酸盐氮的测定较繁琐,干扰物质多,分析时间长,重现性差,准确性不高。文章通过实验介绍一种省时、省力、简便可行不消耗化学试剂且抗氯化物干扰、精度和准确度较高的硝酸盐氮、亚硝酸盐氮总量测定方法。 相似文献
598.
Collivignarelli C Tharnpoopasiam P Vaccari M De Felice V Di Bella V Worakhunpiset S 《Environmental monitoring and assessment》2008,142(1-3):345-358
After 2004 Indian Ocean Tsunami, which hit and devastated several Countries in Southeast Asia, University of Brescia and Mahidol University started a project on water monitoring and treatment for drinking purposes in Takua Pa district (Thailand), the most damaged by the tsunami. In particular, this paper presents the results of a study conducted to evaluate the effectiveness of Takua Pa drinking water treatment plant and to identify actions that could be adopted to improve its performances. The results show that, even if the effluent usually meets Thai guide values, except for pH which is already too acid in the influent, the plant needs several structural and managerial improvements, such as filtration and sedimentation upgrade, coagulation/flocculation and final disinfection re-organization, use of proper registers to better plan and control employees activities. Moreover, it was determined that water quality in the distribution network is characterized by turbidity and organic matter values higher than those evaluated in the plant effluent. 相似文献
599.
Lucadamo L De Filippis A Mezzotero A Vizza S Gallo L 《Environmental monitoring and assessment》2008,146(1-3):453-471
To address the problem of whether hydrographic basins of southern Italian regions such as Calabria are exposed to "ecological stability pressures," we here provide the first results of four chemical and biological (macroinvertebrates) monitoring activities. The data accumulated within four hydrographic basins between May and November of 2002, November of 2005 and May of 2006 showed that about 1/3 of the macrobenthos sampled among a total of 14 rivers in the northern-central part of Calabria region provided optimal environmental quality values of Extended Biotic Index (E.B.I.), 1/3 denoted a slight impairment and the remaining samples exhibited very strong environmental alterations. It is interesting to note that E.B.I. is directly correlated with the taxonomic richness plus abundance, and inversely with the dominating taxon. This suggests that high environmental quality values are rather positively correlated with spatial heterogeneity and taxa eveness. In addition, the more compromised stations were located on plain segments where anthropization is reported to be at its highest level and there the macrobenthic communities seem to be made up of mostly potamon type of taxa with a high abundance of collector euriecious organisms while better quality stations, mostly located at high altitude, are characterized by a considerable presence of E.P.T. taxa. Chemical parameters did not result to be substantially altered underling that the hydrologic and geomorphological alterations may play a primary role in the control of macrobenthic communities and environmental quality. Overall the above results suggest that E.B.I. variations seem to be highly coherent with changes of main biodiversity parameters and their joined application is an efficient tool for detecting ecological state alterations of lotic environments. 相似文献
600.
Monitoring of polychlorinated biphenyl contamination and estrogenic activity in water, commercial feed and farmed seafood 总被引:1,自引:0,他引:1
Pinto B Garritano SL Cristofani R Ortaggi G Giuliano A Amodio-Cocchieri R Cirillo T De Giusti M Boccia A Reali D 《Environmental monitoring and assessment》2008,144(1-3):445-453
We evaluated the concentration and congener distribution of seven "target" polychlorinated biphenyls (PCBs) present in water collected in different aquaculture farms of the Mediterranean area, commercial feeds, and farmed seafood. PCBs were present in feed and in tissues of all the analysed organisms at levels ranging from 1.96 ng g(-1) to 124.00 ng g(-1) wet weight, and in 10.5% of the water samples, at levels from under detection limit to 33.0 ng l(-1) with total PCB concentrations significantly higher in samples from the Tyrrhenian Sea than the Adriatic Sea. PCB congener distribution in tissues resembled that of feed, suggesting that commercial feed is an important source of PCBs. The estrogenicity of organic extracts of the samples was also evaluated by using an in vitro yeast reporter assay. Estrogenic activity higher than 10% of the activity induced by 10 nM 17 beta-estradiol was observed in 20.0% of seafood samples and 15.8% of water samples. Seafood and water samples from the Tyrrhenian Sea were more frequently estrogenic than the Adriatic ones (16.45 versus 4.08%). A significant correlation of total PCB concentrations on biological activity was observed for sea bass and mussels from the Adriatic Sea (p < 0.045 and p < 0.04, respectively), and for sea bass of the Tyrrhenian Sea (p = 0.05). These results indicate the need of an integral approach in the exposure assessment to potential toxic compounds for human via food. 相似文献