The aqueous solubilities of seven chlorobenzenes (1,4-dichlorobenzene, 1,2,3-trichlorobenzene, 1,3,5trichlorobenzene, 1,2,3,5-tetrachlorobenzene, 1,2,4,5-tetrachlorobenzene, pentachlorobenzene, and hexachlorobenzene), five polychlorinated biphenyls (4-chlorobiphenyl, 4,4′-dichlorobiphenyl, 2,4,5-trichlorobiphenyl, 2,3,4,5-tetrachlorobiphenyl, and 2,2′,4,4′,6,6′-hexachlorobiphenyl), and dibenzofuran are reported over the range 5 to 45 °C, from which enthalpies of solution are deduced. The octanol-water partition coefficient (K OW ) of dibenzofuran deduced from its solubilities in octanol, in octanol saturated with water, and in water saturated with octanol is also reported for the same range in temperature, showing agreement with the previously reported value of K OW and much less sensitivity to temperature.