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1.
As a result of air pollutant emissions from the industrial complex of Cubat?o, Brazil, the Atlantic Forest vegetation of the Serra do Mar shows severe and widespread damage. In order to obtain information on the type, intensity and causes of the vegetation damage, bioindicator plants were exposed at different distances from the emission sources. Air-pollution-induced effects were evaluated by estimation of visible injury symptoms and chemical analyses of leaves. The results prove the occurrence of phytotoxic levels of photochemical oxidants in wide parts of the research area. Intense fluoride-induced damage and high leaf fluoride concentrations were found in a valley downwind of fertiliser industries. The study showed that some of the traditional standardised bioindication methods from temperate climates may be successfully employed in biomonitoring programmes in tropical and subtropical regions.  相似文献   

2.
Mutagenic and recombinagenic activity of surface waters in the Guaíba Hydrographic Region (RS, Brazil) was investigated using the SMART in Drosophila melanogaster. Two positive results in Caí River (September 2000 and August 2001) and in Taquari River (August 2001 and February 2002)--linked to direct recombinagenic toxicants were observed. In Jacuí samples, an indirect mutagenic and recombinagenic action was detected in a September 2000 collection and a direct recombinational activity was observed in February 2002. Also in February 2002--samples from Dilúvio Brook and Guaíba Lake (GPC) were able to induce wing spots by mitotic recombinagenesis. The former sampling site showed toxicants to have a direct action, and the latter an increment in mitotic recombination that depended on metabolic action. The SMART wing test shows that all positive responses were mainly related to homologous mitotic recombination.  相似文献   

3.
Spatial distribution of SO2 emission inventory for 1994 from fuel combustion and industrial activities in Shanxi province, the Peoples’ Republic of China, has been created with 1/6°×1/4° latitude/longitude resolution. Total annual SO2 emissions in 1994 in the province were estimated to be 669 GgS, of which 180 GgS were emitted in winter, 170 GgS in spring, 156 GgS in summer, and 163 GgS in fall. For the first time this emission inventory includes SO2 emissions from village and township enterprises. Although SO2 emissions from major industries were under control, SO2 emissions from village and township enterprises became the major threat to the environment in the province.  相似文献   

4.
Environmental Science and Pollution Research - The groundwater environment changes under the influence of anthropogenic activities. Because of the construction of the Da’an irrigation area,...  相似文献   

5.
This paper examines the relation between the results of epidemiologic studies of air pollution mortality and impact indicators that can be informative for environmental policy decisions. Using models that are simple and transparent, yet contain the essential features, it is shown that (1) number of deaths is not meaningful for air pollution, whereas loss of life expectancy (LLE) is an appropriate impact indicator; (2) the usual short-term (time series) studies yield a change in daily number of deaths attributable to acute effects of pollution, without any information on the associated LLE (although some information on this has recently become available by extending the observation window of time series); and (3) long-term studies yield a change in age-specific mortality, which makes it possible to calculate the total population averaged LLE (acute and chronic effects) but not the total number of premature deaths attributable to air pollution. The latter is unobservable because one cannot distinguish whether few individuals suffer a large or many suffer a small LLE. The paper calculates the LLE from exposure to PM10, as implied by the long-term mortality studies of adults and infants; population LLE for infants turns out to be an order of magnitude smaller than for adults. The LLE implied by short-term studies is a small fraction of the total loss implied by long-term studies, even if one assumes a very high loss per death. Applied to environmental policy, taking a permanent 50-70% reduction of PM10 as a reasonable goal, one finds a corresponding increase of average life expectancy in urban areas of the European Union (EU) and the United States of approximately four months.  相似文献   

6.
Vertical gradients of volatile organic compounds (VOCs) were measured over a maize field and a soybean field in 1995 and 1996, respectively, in the Lower Coastal Plains of North Carolina. The measurements over the maize field were conducted in its early growth period, during May 1995, and the measurements over the soybean field were conducted in its middle and later growth periods during July through August 1996 at the same location. These measurements were combined with micrometeorological flux measurements to determine emission flux measurements for various VOCs. This measurement programme was part of project NOVA (Natural emissions of Oxidant precursors: Validation of techniques and Assessment) to estimate the flux of VOCs. Methanol was identified as the major biogenic compound for both years with the average flux of 3450 ± 1456 µg/m²/hr over maize and 3079 ± 2766 µg/m²/hr over soybean. Acetone is another compound that was identified as a biogenic compound for both years with the average flux of 425 ± 223 µg/m²/hr over maize and 2701 ± 1710 µg/m²/hr over soybean. In addition to biogenic compounds, a large number of aromatic compounds, including styrene and 1,2,4-trimethylbenzene, were also identified as emissions from the ground over the soybean field.  相似文献   

7.
Uranium release observed in a rock matrix around water-carrying fractures was studied using U-series disequilibrium (USD) modelling and mass balance calculations. Several release scenarios were tested, with specific attention to the glacial aspects. The release appears to have occurred in two or three violent episodes during the last 300 ky. A release after the last glaciation can be excluded on mass flow grounds. Continuous release for more than 300 ky can be excluded on radioactive disequilibrium grounds. Repeated inflows of oxic glacial meltwater seem to have triggered the release episodes.  相似文献   

8.
Field measurements were made of greenhouse gas emissions from a wastewater treatment system using open path monitoring with detection by FTIR spectroscopy. Emission rates were determined by the ratio technique using a sulfur hexafluoride tracer gas released from a line source. As a quality control check, a second tracer gas – ethylene – was released from various single point locations. This paper presents a comparison of the line-source and point-source tracer releases for approximating emissions from the area source. The two types of tracer release showed excellent agreement when both release points were two hundred meters from the FTIR beam path. Data for other release points also were comparable, once differences in vertical dispersion as a function of distance are taken into account.  相似文献   

9.
In this paper the time evolution of heavy metal concentration of Pb, Zn, Cd and Hg, in the sediments of the Bay of Cádiz (southwest of Spain) is studied during the past century, as a result of the industrial influence in the zone. The study has been performed using sedimentary profiles that have been extracted from the seabed. The measurement of 210Pb and 137Cs radionuclides has provided the dating of the sediment layers, up to a depth corresponding to the age of 115 years. The relative sedimentation rates obtained are around 0.2 cm/year. The 137Cs activity profile reflects the concentration of this radionuclide in the atmosphere and into aquatic systems during the second half of the twentieth century. This profile has been used to ratify the results provided by the 210Pb dating method.  相似文献   

10.
Environmental Science and Pollution Research - Moroccan employers have a strong responsibility for the safety and health of their employees in the workplace and for protecting them from the risk of...  相似文献   

11.
12.
Environmental Science and Pollution Research - Antimicrobials of natural origin are proving to be an effective solution to emerging antimicrobial resistance and its physiological side effects....  相似文献   

13.
Environmental Science and Pollution Research - This research paper deals with the experimental investigation of solar energy–based water purifier (SEBWP) of single-slope type by incorporating...  相似文献   

14.
The general objective of this work was to develop a monitoring and management model for aquatic plants that could be used in reservoir cascades in Brazil, using the reservoirs of AES-Tietê as a study case. The investigations were carried out at the reservoirs of Barra-Bonita, Bariri, Ibitinga, Promiss?o, and Nova-Avanhandava, located in the Tietê River Basin; Agua Vermelha, located in the Grande River Basin; Caconde, Limoeiro, and Euclides da Cunha, which are part of the Pardo River Basin; and the Mogi-Gua?u reservoir, which belongs to the Mogi-Gua?u River basin. The main products of this work were: development of techniques using satellite-generated images for monitoring and planning aquatic plant control; planning and construction of a boat to move coating plant masses and an airboat equipped with a DGPS navigation and application flow control system. Results allowed to conclude that the occurrence of all types of aquatic plants is directly associated with sedimentation process and, consequently, with nutrient and light availability. Reservoirs placed at the beginning of cascades are more subject to sedimentation and occurrence of marginal, floating and emerged plants, and are the priority when it comes to controlling these plants, since they provide a supply of weeds for the other reservoirs. Reservoirs placed downstream show smaller amounts of water-suspended solids, with greater transmission of light and occurrence of submerged plants.  相似文献   

15.
Environmental Science and Pollution Research - Environmental pollution is one of the major problems facing human health, ecosystems, and biodiversity. This is particularly the case for water...  相似文献   

16.
An extensive dataset of VOC measurements was collected at the Sonnblick Observatory, Austria (3106 m) in Fall/Winter 1999/2000, showing high mixing ratios of anthropogenic and biogenic VOCs at this high altitude site due to upward mixing of air masses (Geophys. Res. Lett. 2F (2001) 507). Here we give an interpretation of proton-transfer-reaction (PTR-MS) mass scans obtained in November 1999 based on fragmentation data, GC-PTR-MS analysis and the variability-lifetime relationship, described by the power law, σ(ln(x))=b. The variability-lifetime plot of anthropogenic VOCs gave a proportionality factor A of 1.40 and a,b exponent (sink term) of 0.44 and allowed an estimate of average HO-densities on the order of (1.5±0.4)×105 molecules cm−3. Additionally we were able to indirectly determine a diurnal HO-profile with peak values of (1.3±0.5)×106 molecules cm−3 around midday. HO-reaction rate coefficients for higher aldehydes (heptanal to nonanal) were estimated due to photochemical losses during a stagnant air episode (27 November) and from the variability-lifetime relationship. Combining long term PTR-MS analysis of VOCs and the variability-lifetime method provides a valuable tool for assessing the dominant cause of the variability in VOC concentrations. This information is essential in understanding the sources and photochemical processing of VOCs detected in ambient air at field measurement sites.  相似文献   

17.
To evaluate sediment quality in different areas in the Gulf of Cádiz affected by mining activities, an integrative approach to assessment was used: the Sediment Quality Triad (SQT). Sediment samples were collected at six stations and subjected to replicated sediment acute and chronic toxicity tests, and comprehensive sediment chemistry analyses. Organisms collected synoptically at the same stations were analyzed for histopathological lesions and chemical concentrations in their tissues to determine 'in situ' alteration and bioavailability, in place of benthic community structure. The results obtained for each component were linked to the SQT using different methodologies of interpretation and expression of the integrated approach: (a) multivariate analysis, (b) significant statistical differences compared to the reference stations, (c) ANOVA-based pie charts, and (d) classical methods using triangles and the SQT index of pollution. SQT results indicated that the highest pollution was mainly associated with metals from mining activities and polyaromatic hydrocarbons in the Ría of Huelva. The use of histopathological measures and bioaccumulation of metals, improved the characterization of 'gray areas' of pollution and in the determination of the bioavailability of metals.  相似文献   

18.
Environmental Science and Pollution Research - The determination of trace-level pharmaceuticals in water is generally performed using liquid chromatography combined with mass spectrometry, which is...  相似文献   

19.

Preface

The age of E-mail Submission has passed — The Age of ESS Submission has arrived  相似文献   

20.
This study was intended to provide data on the composition of soft PVC toys, addressing the widest practicable range of chemical additives and including non-phthalate additives. The study also included toys from as many countries as possible, since for many, no data were available. A total of 72 toys were purchased in 17 countries. The majority (64) were PVC or had PVC sections. In almost all the soft PVC toys analysed, phthalates comprised a sizeable proportion (most frequently 10–40%) of the total weight of the toy. The predominant phthalates detected were diisononyl phthalate (DINP) and di(2-ethylhexyl) phthalate (DEHP). Other phthalates identified in high concentrations in some toys include isomeric mixes of diisooctyl phthalate (DIOP) and diisodecyl phthalate (DIDP). The estrogenic chemical nonylphenol was isolated from 13 toys, while 2 toys were found to contain the fungicide Fungitrol 11 (Folpet). 78% of PVC toys contained one or more extractable organic compounds in addition to those reported above. Some of these data have been released previously by Greenpeace and made available on the internet.This report, however, which is intended for a technically expert audience, has been peer reviewed and contains further analytical data that have not been published before.  相似文献   

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