[Dioxins in agricultural soil of Poland]

Total PCDDs concentration ranged from 6.8 to 41 pg g d.w. and for PCDFs from 3.9 to 19 pg/g d.w. with total toxic equivalency within a range 0.023-5.9 pg TEQ/g d.w. A somewhat elevated concentrations of PCDDs and PCDFs were found in the samples collected from the south of Poland in the vicinity of highly industrialized regions known for former extensive mining industry of hard coal and metallurgy, as well as for regions with high rates of urbanization in central Poland and in the vicinity of the western border of the country. Nevertheless, if consider homologue specific pattern of PCDDs and PCDFs no major differences were noted between spatially scattered sampling sites. In all samples highly chlorinated PCDDs/DFs dominated (12345678-OcCDD, 1234678-HpCDD, 12346789-OcCDF, 1234789-HpCDF, 1234678-HpCDF were found in all investigated soils). Their similar pattern can suggest that formation of these chemicals occur in similar conditions. Energy production and fossil fuel co-fired power boilers, chemical industry, metallurgical industry are probably the main sources in industrial regions, however heating of houses by small stoves and hard coal with added household wastes, and former use of agrochemical formulations consisting byimpurities of PCDD/F may also play important role at rural sites. The particularly elevated concentrations of OcCDF in some samples might be connected to the former production and use of highly chlorinated polychlorinated biphenyl formulation--Chlorofen.