Bioconcentration and uptake kinetics of chlorobenzenes in soy-bean roots

Excised soy-beanroots were exposed to an aqueous solution of five homologous chlorobenzenes in constant concentration. The results were in general agreement with water-lipid partitioning. The relationship between the bioconcentration factor and the octanol-water partition coëfficiënt (K_OW) can be used to estimate bioconcentration. Effective equilibrium was reached within 2.5 hours for 1,2-di-, 1,3,5-tri- and 1,2,3,4-hexachlorobenzene and after a mean of 10.1 and 17.9 hours for penta- and hexachlorobenzene respectively. For 1,2-dichlorobenzene, 1,3,5-trichlorobenzene and 1,2,3,4-tetrachlorobenzene the elimination rate constant was > 4.1, and 0.46 and 0.30 hr⁻¹ for penta- respectively hexachlorobenzene. In the range log K_ow 4.56–5.77, k₂ was negatively correlated with log K_OW but k₁ was not correlated with log K_OW..