CONCENTRATIONS OF 2,3,7,8-CHLORINATED DIBENZO-P-DIOXINS AND DIBENZOFURANS AT LANDFILLS AND DISPOSAL SITES FOR CHLOROPHENOLIC WOOD PRESERVATIVE WASTES

Concentration patterns of 16 key 2,3,7,8-substituted PCDD/F congeners were analysed at ppt levels in waste, soil, sediment and leachate samples from 3 mixed-waste landfills, 2 sawmill dumps and the disposal site of the factory which produced the mixture of 2346-TeCP, PCP and 246-TCP used as wood preservative at Finnish sawmills. At this site, I-TE sum of 21 ngg-1 (DS) was observed in leacbate discharge dike sediments, the main contributing analytes being 123678-HxCDF, 1234678-HpCDF (at a level of 700 ngg-1) and 1234678-HpCDD. Also OCDF (at 490 ngg-1), OCDD and 1234678-HxCDD were among the most abundant congeners. In sawmill dump wastes, OCDF or HpCDF was dominant, followed by 4-substituted HxCDD/Fs; the maximum I-TE sum was 2.1 ngg-1 (DS). Even in most landfill leachates OCDF and 123678-HxCDFs were the most abundant and important congeners, but the highest I-TE sum (360 pgl-1 in the aqueous phase of perched water) was mainly attributed to 2378-TCDD.