IDENTIFICATION OF LOCAL AND LONG-RANGE SOURCES OF BENZO(A)PYRENE AND SOOT

Different concentrations of benzo(a)pyrene and soot are determined throughout of Europe at the background sites [ 1,2]. It depends not only on local sources, but on long-range transport of pollutants as well. Drastic decline in the concentration of SO2 and NO2 is determined on the eastern coast of the Baltic Sea. Furthermore, the fraquency of concentrations exceeding 10 µg m-3 is decreasing in the air masses coming from western and central Europe since 1990, while concentrations of benzo(a)pyrene (BP) and soot are changing insignificantly [3]. These facts encourage us to analyse reasons of variation in concentration of carbonaceous materials at the Preila background station (eastern coast of the Baltic Sea). Concentrations of benzo(a)pyrene and soot were measured daily in the period of 1980-1994. Concentrations of the pollutants were divided into four groups according to the directions of air mass trajectories and directions of wind. The highest concentrations of pollutants are determined in the air masses coming from western and central Europe in the period of 1980-1984. An insignificant decline in concentration of benzo(a)pyrene is determinedt in cold season of the year (October-April) from these directions since 1985 and in concentration of soot since 1990. Since this time the concentration of 0.5-1.0 ng/m3 for benzo(a)pyrene and of 0.1-1.0µg m-3fo