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21.
Cariñanos P Sánchez-Mesa JA Prieto-Baena JC Lopez A Guerra F Moreno C Dominguez E Galan C 《Journal of environmental monitoring : JEM》2002,4(5):734-738
The aim of this study was to analyse the relationship between the distribution of hay-fever patients in the city of Córdoba, south-western Iberian Peninsula, and the specific atmospheric biological content originating from local sources. Four different districts were established in the metropolitan area of the city, according to vegetational and urbanistic characteristics. Air samples were taken in each area using portable Hirst-type samplers (Lanzoni VPPS 1000) and the spectrum of biological content was defined. Patients attending the Allergy Unit at Córdoba Teaching Hospital in 2000 with allergic rhinitis and/or asthma, and displaying a positive reaction to aeroallergen extracts, were distributed within the areas as a function of their district of residence. Aerobiological results revealed differences in pollen content between areas, in terms of both quantity and number of pollen types recorded. These differences were largely due to proximity to rural areas, prevalence of pollen from typically urban species and the possible effect of urban architecture as a barrier to the dispersal/ concentration of particles and other pollutants. Patients were not uniformly distributed within the city. The majority lived in districts in which pollen from rural species was mixed with pollen from ornamentals. Patients living in typically urban districts displayed a higher prevalence of allergy to pollen from ornamentals. It is concluded that a high degree of exposure to the same environment may influence the development of sensitisation to the particular pollen load associated with that area. 相似文献
22.
Santamaría-Fernández R Moreda-Piñeiro A Hill SJ 《Journal of environmental monitoring : JEM》2002,4(2):330-336
The optimisation of a simple multielement extraction method employing an experimental design approach is described. The method uses centrifugation to pass one extractant solution at varying pH through a contaminated soil sample. The nature and concentration of the acid, rate of centrifugation and time, number of sequential leachates and the ratio of extractant volume: sample weight have been studied in order to obtain the optimum conditions for extraction. A fractional factorial experimental design was performed, and the results were used to identify significance which was then evaluated by carrying out a central composite experimental approach. Once optimum conditions had been obtained, sequential leaches were analysed by ICP-AES and chemometrics were employed to identify the composition of each component. Comparisons have been made with previous studies and tentative assignments, based on well defined separated fractions and percentage compositions for individual elements, used to identify the different physico-chemical components in the sample. 相似文献
23.
Fagundez LA Fernández VL Marino TH Martín I Persano DA Rivarola Y Benítez M Sadañiowski IV Codnia J Zalts A 《Environmental monitoring and assessment》2001,71(1):61-70
Passive diffusion samplers were employed in San Miguel(Buenos Aires Metropolitan Area) for a preliminary airpollution monitoring. The highest loads were observedin downtown, compared with an urban background site.Total suspended particulate matter (TSPM) varied from0.257 to 0.033 mg cm-2 month-1; dust was examinedfor particle nature and size distribution. A similartrend was observed for nitrogen dioxide (NO2) andTSPM spatial distribution, suggesting that traffic isthe major pollution source. Sulphur dioxide (SO2)values were low and rather homogeneous. Levels for theinvestigated pollutants are below EPA's guide linevalues. Geographic (flat area, near to Rio de LaPlata) and climatologic factors (rainfalls andvariable wind directions) contribute to disperse pollutants. 相似文献
24.
Gustavo Ratto Fabián Videla J. Reyna Almandos Ricardo Maronna Daniel Schinca 《Environmental monitoring and assessment》2006,121(1-3):325-340
This article presents and discusses SO2 (ppbv) concentration measurements combined with meteorological data (mainly wind speed and direction) for a five-year campaign (1996 to 2000), in a site near an oil refinery plant close to the city of La Plata and surroundings (aprox. 740.000 inh.), considered one of the six most affected cities by air pollution in the country. Since there is no monitoring network in the area, the obtained results should be considered as medium term accumulated data that enables to determine trends by analyzing together gas concentrations and meteorological parameters. Preliminary characterization of the behaviour of the predominant winds of the region in relation with potential atmospheric gas pollutants from seasonal wind roses is possible to carry out from the data. These results are complemented with monthly averaged SO2 measurements. In particular, for year 2000, pollutant roses were determined which enable predictions about contamination emission sources. As a general result we can state that there is a clear increase in annual SO2 concentration and that the selected site should be considered as a key site for future survey monitoring network deployment. Annual SO2 average concentration and prevailing seasonal winds determined in this work, together with the potential health impact of SO2 reveals the need for a comprehensive and systematic study involving particulate matter an other basic pollutant gases. 相似文献
25.
Peter A. Beedlow Don S. Daly Michael E. Thiede 《Environmental monitoring and assessment》1986,6(3):277-282
An electrical device capable of continuously measuring micronsized changes in stem diameter of woody and herbaceous plants is described. Fumigation of sunflowers with automotive exhaust was used to test the ability of the device to detect short-term plant responses. 相似文献
26.
Extreme pollutant values are of great interest in water quality monitoring because of their frequent toxicological significance. The principal barrier to the detection of these values, however, is the cost of extensive and comprehensive monitoring. This paper demonstrates an efficient method to determine the maximum sample measurement from a finite set of sequential samples without explicitly testing them all. It is assumed that the process of sample measurement is distinct from collection and has higher costs. It is further assumed that the measurements have high positive autocorrelation.A methodology is presented based on a common industrial testing procedure referred to as composite sampling—the physical pooling or compositing of a set of sequential samples before measurement. A method known as primary first order compositing (PFOC) was found to be superior to the traditional technique of random sampling, particularly if small composite sizes are utilized.The authors are, respectively, operations research analyst, Vancouver, B. C.; Associate Professor and Chairman, Policy Analysis Division, Faculty of Commerce and Business Administration, University of British Columbia; and Associate Professor, Management Science Division, Faculty of Commerce, U.B.C. 相似文献
27.
Pacáková V Pockeviciute D Armalis S Stulík K Li J Veselý J 《Journal of environmental monitoring : JEM》2000,2(2):187-191
Experiments were carried out to monitor the equilibrium distribution of lead, cadmium and copper between an aqueous phase modelling natural water and a solid phase modelling natural sediment, under varying conditions. The aqueous phase was analysed using ETAAS and differential pulse anodic stripping voltammetry (DPASV), whereas XRD and FTIR were used to study the solid phase. Sorption isotherms at constant pH were measured. Conditional distribution constants were calculated as functions of the pH, the time of equilibration and the amount of solid material. The results obtained stress the need for standardization of the approaches to the study of water-sediment interactions in order to be able to evaluate and compare the extensive data from field measurements and to predict these interactions. 相似文献
28.
Sánchez López FJ Gil García MD Martínez Vidal JL Aguilera PA Garrido Frenich A 《Environmental monitoring and assessment》2004,93(1-3):17-29
Water quality assessment in the Aznalcollar area was attempted using multivariate methods based on heavy metal concentrations in red swamp crayfish (Procamburus clarkii). Trace levels of four heavy metals, copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb), were detected in crayfish from eleven different stations. Principal component analysis (PCA) highlighted a gradient of contamination between the sampling stations. Cluster analysis (CA) distinguished three groups of stations. Discriminant analysis also differentiated three groups. The group centroids of the first discriminant function were used to devise an index that varies according to the source of the crayfish. These standardized values are proposed for use as a water quality index. The ability of this index to successfully predict environmental quality was proved with random samples. 相似文献
29.
van Wijk D Thompson RS De Rooij C Garny V Lecloux A Kanne R 《Environmental monitoring and assessment》2004,97(1-3):69-86
This risk assessment on monochlorobenzene was carried out for the marine environment, following methodology given in the EU risk assessment Regulation (1488/94) and Guidance Document of the EU New and Existing Substances Regulation (TGD, 1996). Data from analytical monitoring programmes in large rivers and estuaries in the North Sea area were collected and evaluated for effects and environmental concentrations. Risk is indicated by the ratio of predicted environmental concentration (PEC) to predicted no-effect concentration (PNEC) for the marine aquatic environment. In total, 27 data for fish, 24 data for invertebrates and 13 data for algae were evaluated. Acute and chronic toxicity studies were taken into account and appropriate assessment factors used to define a final PNEC value of 32 micro/l. Recent monitoring data indicate that monochlorobenzene levels in surface waters are below determination limits of 0.1, 0.2, 0.5 microg/l used in monitoring programs. Assuming that half of the lowest determination (0.1 microg/l) is typical, a PEC of 0.05 microg/l was derived. A worst case of 0.5 microg/l is assumed. PEC/PNEC ratios give safety factors of 60 to over 500, taking no account of dilution in the sea. Monochlorobenzene is not a 'toxic, persistent and liable to bioaccumulate' substance sensu the Oslo and Paris Conventions for the Prevention of Marine Pollution (OSPAR-DYNAMEC) criteria. Environmental fate and effects data indicate that current use of monochlorobenzene poses no unacceptable risk to the aquatic environment. 相似文献
30.
José Roberto Ferreira 《Ambio-人类环境杂志》2003,32(1):47-51
引言 莫日-瓜苏河位于纳斯吉拉斯州,海拔高1450m.流淌470km后,该河流注入圣保罗州的帕尔杜河.其流域总面积为1400km2,其中有86%位于圣保罗州,包括一个工业化地区[1]. 相似文献