Transport of PAH by Ciliates (IMAGE) Aarhus University Caption The ciliates' increase of the mobility of PAH grows the more hydrophobic the PAHs are (from the left to the right on the figure) since more PAH is incorporated into the ciliates' fatty cell membrane. Kow is an expression of chemical compound water solubility. The higher Kow (octanol:water distribution), the more hydrophobic the PAH (and thereby fat-soluble, lipophilic) are. Credit Dorothea Gilbert, Aarhus University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.