Suchergebnisse

This study presents the results of a yearlong PM10 measurement campaign, conducted at four sampling sites, within the Greater Athens Area, between June 2001 and May 2002. Daily average PM10 concentrations were determined using reference samplers installed in two urban locations (Maroussi and Aristotelous), a mixed urban-industrial location (Elefsina) and a background location (Thrakomacedones). The 24-h and annual PM10 average concentrations were calculated and compared to the corresponding air quality standards, promulgated by the European Union, revealing severe exceedances of the limit values. The mean concentrations for the sampling periods were 73.8, 83.2, 32.9 and 54.9 mug/m(3) for Maroussi (MAR), Aristotelous (ARI), Thrakomacedones (THR) and Elefsina (ELE), respectively. The spatial variation of PM10, was investigated resulting at a coefficient of variation of 0.36 within the study area and correlation coefficients ranging from 0.57 to 0.84. In addition, strong associations between PM10 and other primary gaseous pollutants were found. Regression analysis of PM10 against NOx (used as an indicator for road traffic emissions) revealed significant vehicular contributions to the measured PM10 concentrations. Higher PM10 levels were recorded during prevailing winds of the S-SW sectors, while lower levels were observed during strong northerly flows. The overall results allowed a first assessment of the severity of PM10 air pollution in the Athens basin, and of the potential sources responsible for it. The control of traffic-related particle emissions appears to be a principal objective, for the confrontation of the PM10 pollution problem affecting the area.

During the period of 1 June 1999 through 31 May 2000, PM2.5 and PM10 concentrations were measured in downtown Athens, Greece. The monitoring site was located 6.7 m above ground near a highly trafficked and congested road. Daily PM10 and PM2.5 samples were collected using semi-automatic low-volume samplers. The average 24-h PM10 concentration during the sampling period was 75.5 mug/m(3). Daily PM10 concentrations exceeded the European Union limit (for the year 2000) for approximately 42% of the sampling days. The average PM2.5 measured concentration was 40.2 mug/m(3), which is considerably higher than the United States National Ambient Air Quality PM2.5 annual standard, 15 mug/m(3). The mean coarse particle concentration, PM10 minus PM2.5, was 35.3 mug/m(3) representing about 50% of the average PM10. PM2.5 and PM10 concentrations were highly correlated with carbon monoxide, black carbon and nitrogen oxides and inversely correlated with local wind speed. Regression models using continuous and categorical variables were developed to investigate the complex relationships between meteorological and time period parameters and particle concentrations. The results of this analysis underlined the importance of local emission sources, mostly from traffic, which are responsible for the high PM10 and PM2.5 concentration levels observed during this one year-sampling period. (C) 2003 Elsevier Science Ltd. All rights reserved.