Compilation, evaluation, and selection of physical-chemical property data for organochlorine pesticides

Accurate physical-chemical properties (aqueous solubility S-W, octanol-water partition coefficient K-OW, vapor pressure P, Henry's law constant H, octanol-air partition coefficient K-OA, octanol solubility S-O) and their temperature dependence are of fundamental importance for interpreting and simulating the environmental fate and transport of organochlorine pesticides (OCPs). A complete set of property data for 14 organochlorine chemicals is derived by evaluating, averaging, and regressing all measured values reported in the literature. The 14 chemicals are hexachlorobenzene (HCB), pentachlorobenzene (PeCB), cis-chlordane, trans-chlordane, 1,1,1-trichloro-2,2-bis-4-chlorophenyl-ethane (pp '-DDT) and its metabolites 1,1-dichloro-2,2-bis-4-chlorophenyl-ethene (p,p '-DDE) and 1,1-dichloro-2,2-bis-4-chlorophenyl-ethylene (p,p '-DDD), heptachlor and its metabolite heptachlor epoxide, aldrin, dieldrin, endrin, alpha-endosulfan, and beta-endosulfan. Properties for each individual chemical are adjusted to ensure thermodynamic consistency. That adjustment is sized according to, and is usually smaller than, the measurement uncertainty. Internal energies of phase transfer A U could be derived only for HCB and PeCB. The lack of property measurements as a function of temperature for the other chemicals prevents their Delta U values from being derived.