Personal exposure to particles in Banska Bystrica, Slovakia

Epidemiological studies have associated adverse health impacts with ambient concentrations of particulate matter (PM), though these studies have been limited in their characterization of personal exposure to PM. An exposure s tudy of healthy nonsmoking adults and children was conducted in Banska Byst rica, Slovakia, to characterize the range of personal exposures to air poll utants and to determine the influence of occupation, season, residence loca tion, and outdoor and indoor concentrations on personal exposures. Twenty-f our-hour personal, at-home indoor, and ambient measurements of PM10, PM2.5, sulfate (SO42-) and nicotine were obtained for 18 office workers, 16 indus trial workers, and 15 high school students in winter and summer. Results sh owed that outdoor levels of pollutants were modest, with clear seasonal dif ferences: outdoor PM10 summer/winter mean = 35/45 mug/m(3); PM2.5 summer/wi nter mean = 22/32 mug/m(3). SO42- levels were low (4-7 mug/m(3)) and relati vely uniform across the different sample types (personal, indoor, outdoor), areas, and occupational groups. This suggests that SO42- may be a useful m arker for combustion mode particles of ambient origin, although the relatio nship between personal exposures and ambient SO42- levels was more complex than observed in North American settings. During winter especially, the cen tral city area showed higher concentrations than the suburban location for outdoor, personal, and indoor measures of PM10, PM2.5, and to a lesser exte nt for SO42-, suggesting the importance of local sources. For PM2.5 and PM1 0, ratios consistent with expectations were found among exposure indices fo r all three subject groups (personal>indoor>outdoor), and between work type (industrial>students>office workers). The ratio of PM2.5 personal to indoo r exposures ranged from 1.0 to 3.9 and of personal to outdoor exposures fro m 1.6 to 4.2. The ratio of PM10 personal to indoor exposures ranged from 1. 1 to 2.9 and the ratio of personal to outdoor exposures from 2.1 to 4.1. Fo r a combined group of office workers and students, personal PM10/PM2.5 leve ls were predicted by statistically significant multivariate models incorpor ating indoor (for PM2.5) or outdoor (for PM10) PM levels, and nicotine expo sure (for PM10). Small but significant fractions of the overall variability , 15% for PM2.5, and 17% for PM10, were explained by these models. The resu lts indicate that central site monitors underpredict actual human exposures to PM2.5, and PM10. Personal exposure to SO42- was found to be predicted b y outdoor or indoor SO42- levels with 23-71% of the overall variability exp lained by these predictors. We conclude that personal exposure measurements and additional demographic and daily activity data are crucial for accurat e evaluation of exposure to particles in this setting.