Partition constants of chlorinated dibenzofurans and dibenzo-p-dioxins

Vapour pressure, aqueous solubility, Henry law constant, n-octanol- and sediment-water partition coefficient and bioconcentration factor of all chlorinated dibenzofurans (PCDF) and dibenzo-p-dioxins (PCDD), in addition to those of the parent compounds DF and DD, were calculated via the SOFA (SOlubility parameters for Fate Analysis)- model. The derivation of these 1272 values was based on 120 experimental data. Mean deviation of calculated values from experimental data amounted to 0.39, 0.25, 0.31, 0.19, 0.34 and 0.18 log units for the properties mentioned. The values of all compounds were tabulated. Variation of values within isomer groups turned out to be the highest for vapour pressure of the tetra substituted group, but were below 1.40 orders of magnitude. Variation in the complete series amounted to 7.78 orders at a maximum, again for vapour pressure. Accurate, almost linear, relationships were established between the n-octanol-water partition coefficient and aqueous solubility and sediment-water partition coefficient, whereas a parabolic relationship turned out to hold with the bioconcentration factor.