Transmembrane transports of four kinds of lipophilic organic chemicals (LOCs) on suspending multilamellar liposomes (SML) and Escherichia coli (E. coli) were investigated, where both anthracene and phenanthrene were accorded to the lipid-water partition law and Sudan I and III to the Langmuir isothermal adsorption. Less than half of phenanthrene is transported into E. coli, where more than 60% are located in the cytoplasm. About 60% of anthracene entered the E. coli where only 10% was released into the cytoplasm. The partition coefficients of phenanthrene and anthracene partitioning from the extracellular liquid into membrane are 502 and 1190 L/kg but their inverse partition coefficients are only 0.180 and 0.018 kg/L Over 60% of Sudan land less than 40% of Sudan III accumulated on E. coli where most of them remained on the membrane. The transmembrane impedance effect (TMIE) is proposed for evaluating the cell-transport of polar LOCs. (C) 2010 Elsevier Ltd. All rights reserved.