Prediction of environmental partition coefficients and the HenryÕs law constants for 135 congeners of chlorodibenzothiophene Tomasz Puzyn, Pawel Rostkowski, Artur S ´ wieczkowski, Aneta Je ˛ drusiak, Jerzy Falandysz * Department of Environmental Chemistry and Ecotoxicology, University of Gdan ´ sk, 18 Sobieskiego Street, PL 80-952 Gdan ´ sk, Poland Received 2 September 2004; received in revised form 31 May 2005; accepted 9 July 2005 Available online 7 October 2005 Abstract Polychlorinated dibenzothiophenes (PCDTs) could be classified as persistent organic pollutants (POPs) in the envi- ronment and are particularly interesting due to their structural resemblance to highly toxic dioxins. We show here some basic environmental properties such as n-octanol water (K OW ), n-octanol/air (K OA ) and air/water (K AW ) partition coef- ficients as well as HenryÕs law constants (K H ) for all 135 congeners of chlorodibenzothiophene. Predictions were made by regression of principal components (PCR) and with aid of a set of standard chemicals, for which physical–chemical properties are well featured. Computed K OW , K OA , K AW and K H values for mono-CDTs ranged, respectively, between 4.66 and 4.71, 7.48 and 7.55, 2.84 and 2.82, 3.56 and 3.74; for di-CDTs between 5.02 and 5.28, 8.03 and 8.29, 3.01 and 2.95, 2.42 and 2.75; for tri-CDTs between 5.53 and 5.70, 8.65 and 8.87, 3.2 and 3.11, 1.58 and 1.92; for tetra- CDTs between 5.95 and 6.13, 9.27 and 9.50, 3.39 and 3.27, 1.02 and 1.33; for penta-CDTs between 6.38 and 6.51, 9.88 and 10.05, 3.54 and 3.45, 0.72 and 0.88; for hexa-CDTs between 6.83 and 6.97, 10.54 and 10.66, 3.72 and 3.64, 0.47 and 0.56; for hepta-CDTs between 7.28 and 7.35, 11.12 and 11.20, 3.81 and 3.87, 0.33 and 0.38; for octa-CDT 7.74, 11.78, 4.04 and 0.23. An estimated value of the three types of partition coefficient and HenryÕs law constants suggest that polychlorinated dibenzothiophenes are lipophilic and semi-volatile persistent organic pollutants. Their mobility in the environment seems to be very similar to that of some well-known POPs such as polychlorinated dibenzofurans, -dibenzo-p-dioxins, and -biphenyls or organochlorine pesticides. Ó 2005 Elsevier Ltd. All rights reserved. Keywords: Chlorodibenzothiophene; Polychlorinated dibenzothiophenes; PCDTs; Dioxin-like compounds; Physical–chemical prop- erties; Environmental chemistry; QSPR 1. Introduction 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and its 2,3,7,8-substituted analogues of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated di- benzofurans (PCDFs), but also planar polychlorinated 0045-6535/$ - see front matter Ó 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.chemosphere.2005.07.055 * Corresponding author. Tel.: +48 58 3450372; Fax: +48 58 3450472. E-mail address: jfalandy@chem.univ.gda.pl (J. Falandysz). Chemosphere 62 (2006) 1817–1828 www.elsevier.com/locate/chemosphere