PM sub(10) and black smoke in a small settlement: case study from the Czech Republic

Twenty-four-hour concentrations of PM sub(10) and black smoke (BS) were measured during two winter and one summer periods in a small village in the central part of the Czech Republic. Both the PM sub(10) and BS were highly correlated during the two heating seasons (0.740 in the first and 0.768 in the second winter campaign, respectively). The correlation dropped to 0.567 during the summer period. Negative correlation between winter BS and wind velocity (- 0.543 and-0.486) showed a close association between air pollution from combustion and low air mass movement in the locality during heating seasons. No correlation between BS and wind velocity was found during summer (0.057). Both PM sub(10) and BS were negatively correlated with minimum daily temperature during both winter seasons as well as during the summer season. Comparison of PM sub(10) data from the village with those from Prague, the Czech capital, showed that average particulate matter concentrations in the rural site were higher during all the three seasons studied. Recommended 24-h limit for PM sub(10) in the European Union (50 [mu]g m[super]-3) was exceeded in 26% and 33% of days measured in the small village while only in 17% and 15% of days measured in Prague, for the first and second winter, respectively. Good association between data from the village with those from Prague suggests, on the one hand, that some effect of particulate matter transport from the city to the rural site cannot be excluded but, on the other hand, that good accord may be caused by similar climatic conditions of the two settlements. The results of the study support the idea that traditional heating in villages may represent an important air pollution problem.