CHARACTERISATION OF PARTICULATE MATTER PM10 AND PM2.5 IN NORTHRHINE WESTPHALIA, SAXONIA AND LITHUANIA FIRST RESULTS

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1 ., Ann. occup. Hyg., Vol. 41, Supplement 1, pp , 1997 r ergamon (Q 1997 British Occupational Hygiene Society Published by Elsevier Science Ltd. All rights reserved Printed in Great Britain /97 $ Inhaled Particles VIII PII: S (96) CHARACTERISATION OF PARTICULATE MATTER PM10 AND PM2.5 IN NORTHRHINE WESTPHALIA, SAXONIA AND LITHUANIA FIRST RESULTS E. Kainka,* G. Kramert and J. Dudzeviciusij: *Medical Institute of Environmental Hygiene at the University, Auf m Hennekamp 50, D Dusseldorf, Germany, tlnstitute of Hygiene at the University of Leipzig, Germany, and ^Medical Academy of Kaunas, Lithuania INTRODUCTION The measurement of equal concentrations of total suspended particulate matter (TSP) in different areas may not cause equal effects on human health because of differences in the quantity of PM10 and PM2.5 as well as variations with regard to the components. Epidemiological studies in U.S. cities emphasised the importance of PM10 measurement and especially the measurement of PM2.5 instead of TSP. The correlation between daily mortality and PM10 concentration or especially PM2.5 concentration in urban areas was very high. A lower correlation was attributed to the coarse fraction of PM10. Therefore, more specific studies should concentrate on the finer fractions of airborne particulate matter. That is the reason why the international and especially the European discussion tends more and more to the measurement of PM10 and/or PM2.5. The United States has done measurements of PM2.5 since the beginning of The PM10 and PM2.5 fractions are different compositions of several classes of pollutants. They differ also in their sources, amount, size, in physical and chemical behaviour and even in ability to penetrate from outdoors to indoors. The last point makes PM2.5 measurements more important in interpreting community exposure. This paper will analyse and characterise the PM10 measurements and particle components of the coarse and fine fraction in several urban areas of Northrhine Westphalia, Saxonia and Lithuania as well as of special sources of pollutants like road traffic, industry and heating. Electron microscopical studies, chemical and crytallographical analysis of single particles and collections of particles characterise the components of several fractions and study areas. The identification of components may give hints on toxic effects. METHODS Study areas One of three study areas in Northrhine Westphalia is in Dusseldorf, with a measuring point at a testing container in Dusseldorf Morsenbroich that is situated at a multiple cross roads. Another study area is Duisburg. Mostly industrial air pollutants are measured at this testing container in Duisburg Walsum. The third 54

2 Characterisation of participate matter PM10 and PM2.5 first results 55 study area is the small town of Borken situated north of the Ruhr area. Nearly clean air conditions are measured at a testing container in Borken. The study area in Saxonia is Leipzig, with measurements at a testing container in the South of Leipzig, where specially air pollution due to heating can be measured. The three study areas of Lithuania are situated in Kaunas at testing containers or stations. At station 1 mainly the traffic air pollution is measured, at station 2 the heating air pollution and at station 3 industrial air pollution. Sampling method The sampling instrument used is a low volume PM10 dichotomous sampler by Graseby Andersen. The volume air flow is 1 cubic metre per hour. This impactor divides the finer suspended particles in the two fractions PM10 coarse and PM10 fine (= PM2.5). These samplers are exposed near to testing containers in the study areas. During several 24 h measurements, particulates of the coarse and fine fraction are collected on glass fibre filters to determine the concentrations and also for later extraction and chemical analysis. During 2 h measurements, particulates of the two fractions are collected on poly-carbonate filters with a poresize of 2 im that will be used for scanning and transmission electron microscopical analyses. These discontinuous measurements and sampling methods are planned to cover each season of a year, to get better knowledge of special seasonal influences. Electron microscopy Particle analyses are done on scanning and transmission electron microscopy using EDX and diffraction methods. RESULTS Concentration of PM10 coarse and fine (PM2.5) In general, variations of the concentrations of PM10 coarse and fine can be observed during a week. Examples of maximum and minimum daily amount of PM10 and its coarse and fine fraction in the study areas of Northrhine Westphalia at wintertime are shown in Figs 1 and 2. In Leipzig (south) four continuous 24 h measurements are done in winter on a Thursday up to a Sunday. The daily amount of PM10 and its coarse and fine fraction can be seen in Fig. 3. The measured concentrations of the Lithuanian stations are not yet available. Paniculate components Coarse particulates collected at the Diisseldorf-Morsenbroich station (traffic air pollution) are dominated by large soot agglomerates in addition of tyre abrasion and geogenic clay minerals. Fine particulates are mainly single soot particles or small soot agglomerates. Coarse particulates collected at the Duisburg-Walsum station (industrial air pollution) are slag (mostly from blast furnaces), xenomorphic silica (changed by melting), several salt particles, gypsum and metallic particles. In the fine particulates soot and fly ash dominate. Coarse particulates collected at the Borken station (nearly clean air) are mostly

3 56 E. Kainka et al u g 1500 / d a 1000 y 500 n Northrhine-Westphalia Winter 1995/ TITTTTII^^^" DUSSELDORF PM-10 example: maximum data mill i1 DUISBURG ~*~ M coarse ^1 BORKEN Fig. 1. Example of the maximum daily amount of total PM10 and of the coarse and fine fraction of Dusseldorf-Morsenbroich (Tu, ), Duisburg-Walsum (Th, ) and of Borken (Tu, ) M g 1500 / d a 1000 y 500 H fine Northrhine-Westphalia Winter 1995/96 example: minimum data H ^ H ^ B, D0SSELDORF DUISBURG BORKEN EH PM-10 coarse fine Fig. 2. Example of the minimum daily amount of total PM10 and of the coarse and fine fraction of Dusseldorf-Morsenbroich (Sa, ), Duisburg-Walsum (Sa, ) and of Borken (Sa, %).

4 Characterisation of paniculate matter PM10 and PM2.5 first results 57 Leipzig-South Winter 1995/96 Measurement Thursday to Sunday Th Fr Sa Su PM-10 BH coarse fine Fig. 3. Daily amount of total PM10 and of the coarse and fine fraction of four continuous measurements in Leipzig-South. of biogenic and geogenic origin. Clay minerals and quartz indicate signs of weathering. The fine particulates are silicates and in addition some soot particles. Coarse particulates collected at the Leipzig-South station (heating air pollution) are typical particles of combustion (in addition to particles of traffic air pollution) like soot agglomerates, sometimes with ball-like morphology, charcoal, big and small balls of fly ash, xenomorphic silicates and sulfates like gypsum. The fine particulates are dominated by soot agglomerates and small balls of fly ash (Fig. 4). Coarse particulates collected at the Kaunas station 1 (traffic air pollution) are soot agglomerates, fly ash and clay minerals. Fine particulates are mostly soot particles. Coarse particulates collected at the Kaunas station 2 (heating air pollution) are soot agglomerates, fly ash, charcoal, xenomorphic silicates and sulphates. Fine particulates are soot particles and agglomerates added by small balls of fly ash (Fig. 4). Coarse particulates collected at the Kaunas station 3 (industrial air pollution) are silicate particles, metallic particles and several salts. The fine particulates consist of soot particles, small agglomerates, fly ash and silicates. DISCUSSION The discontinuous measurements of PM10 which have started in Northrhine Westphalia, Saxonia and Lithuania are done by the above-mentioned low volume dichotomous sampler with a sampling rate comparable to the human breathing volume. The sampling of the two fractions of PM10 collects the bimodal aerosols in ambient air, as shown by Wilson et al. (1995). Unlike the measurements of total suspended particles, the separate sampling of

5 58 E. Kainka et al. Fig. 4. Scanning electron micrograph of the PM2.5 fraction: soot agglomerates and fly ash, collected in Leipzig-South at wintertime 1996, magnification: 8000 x. the coarse and fine fraction of PM10 gives much more information, especially in the components and the amount of the PM2.5 fraction. The toxicity of this fraction is reported by epidemiologic studies in U.S. cities. Dockery et al. (1989, 1993) and Wilson et al. (1995) documented high correlations between daily mortality and the daily concentration of PM2.5 in several U.S. cities. Also Monn (1994) reported PM10 concentrations in eight regions of Switzerland. The first results of our measurements show for all stations and kinds of air pollution that there is a day by day variation of the PM10 concentration and the coarse and fine fraction during a week (Figs 1-3). The main variation is in the PM2.5 fraction. In a clean area region, the measured amount of PM2.5 can be smaller than the amount of the coarse fraction of PM10. It can be mentioned that the Lithuanian PM10 concentration in Kaunas is lower than in Germany. The immense reduction of industry in recent time is obvious. With the aim of doing further chemical analyses and to apply cytotoxical and genotoxical tests on extracts of the fractions, we started to analyse the particles and to characterise particles collections of the single fractions and stations according to their source. In all samples of the fine fractions soot particles and fly ash are more or less present. Single soot particles of 10 nm size or, even small soot agglomerates, may reach the alveoli. This is also true for the small balls of fly ash, because of their low density. The high content of heavy metals in this amorphous silica material may be the toxic component. Geogenous particles, for example silicas, derive from mechanical abrasion and are found mostly in coarse fractions. The weathered surface of these particles makes them less toxic than a changed and recrystallised surface of a silicate by combustion. The particulate air pollution caused by traffic is highly concentrated in the fine

6 Characterisation of paniculate matter PM10 and PM2.5 first results 59 fraction. This air pollution cannot just be documented at a typical station with traffic exhaust. The influence of traffic air pollution exists also in the particulate matter of areas with industrial or heating air pollution like Leipzig-South or even in so called clean air areas like Borken. The variations during a week are obvious. On the Lithuanian air pollution it can be mentioned that the air pollution by traffic exhaust is low in contrast to Germany. The traffic density and the number of diesel cars is lower. There are many electric buses in Kaunas and other buses that use normal petrol. The measurements of PM10 and PM2.5 in connection with the single particle analyses continue to develop a detailed and source revealed description of the particulate composition of ambient air in urban and rural areas in Western and Eastern Europe. REFERENCES Dockery, D. W., Speizer, E., Stram, D. O., Ware, J. H., Spengler, J. D., Benjamin, G. and Ferris, J. R. (1989) Effects of inhalable particles on respiratory health of children. Am. Rev. Respir. Dis. 139, Dockery, D. W., Pope, C. A., Xu, X., Spengler, J. D., Ware, J. H., Fay, M. E., Ferries, B. G. and Speizer, F. E. (1993) An association between air pollution and mortality in six U.S. cities. N. Engt. J. Med. 329 (24), Monn, C. (1994) PM10 concentrations and aerosol particle size distribution in outdoor air in eight regions of Switzerland. /. Aerosol Sci. suppl. 1, Wilson, W. E. and Suh, H. H. (1995) Differentiating fine and coarse particles: definitions and exposure relationships relevant to epidemiological studies. Trends in Aerosol Research IV (Seminar in Duisburg on the 27 January 1995), pp