Polychlorinated dibenzo-p-dioxins ͑PCDDs͒ and polychlorinated dibenzofurans ͑PCDFs͒ are of global concern due to their persistence, their tendency to bioaccumulate, and their extremely high toxicity. The fate of the PCDD/Fs in the environment is largely determined by their physical-chemical properties, such as solubility in water ͑S W , mol m −3 ͒, solubility in octanol ͑S O , mol m −3 ͒, and vapor pressure ͑P, Pa͒. It is not unusual that the range of reported values for a given property varies over several orders of magnitude, especially for the highly chlorinated congeners, and consequently, it is a challenge to select physical-chemical property data from the literature for use in chemical fate and risk assessments. In the current study, physical-chemical property data ͓P, S W , S O , Henry's law constant ͑H͒, partitioning coefficients between octanol-water ͑K OW ͒ and octanol-air ͑K OA ͔͒ for 15 DDs and 17 DFs at 293-299 K are compiled from the literature and evaluated to select literature derived values that are then adjusted to conform to thermodynamic constraints using a least-squares adjustment procedure. We also present an analysis of available data on internal energies of phase change ͑⌬U A , ⌬U W , ⌬U O , ⌬U OW , ⌬U AW , ⌬U OA ͒ at 298 K, which describe the temperature dependence of the partitioning properties. The final adjusted values ͑FAVs͒ derived from this study are recommended as physical-chemical property data for PCDD/Fs for use in environmental fate modeling. The FAVs for internal energies of phase change can be used as a first approximation for estimating properties at temperatures other than 298 K.

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Congener distribution patterns at the site were generally dominated by a specific marker congener (1234678-HpCDF), which is highly abundant in the polluted soil. The dioxin toxic equivalents (TEQ) concentrations were notably elevated as compared to national reference samples for most exposure media, and the marker congener was a major contributor to increased TEQ levels. There were also indications of soil-to-air volatilization of tetra- and penta-CDD/Fs. People who participated in the restoration of a contaminated building showed higher levels of 1234678-HpCDF compared to controls, and calculated exposure levels suggest that several site-specific exposure routes may be of importance for the daily intake of PCDD/F. CONCLUSIONS, RECOMMENDATIONS, AND PERSPECTIVES: Despite low mobility of higher chlorinated PCDD/Fs, these contaminants were transferred from the polluted soil to the surroundings and into human tissue. The extent of increased exposure from contaminated sites depends on the PCDD/F source strength of the soil, composition of the pollution, human activities, and dietary patterns of the residents. Impact from the contaminated soil on other exposure media was seen also for areas with low to moderate soil contamination. In the future, not only the levels of PCDD/F soil pollution but also the composition must be considered in risk assessments of contaminated sites.