several organic fatty acids previously reported as DNApolymeraseinhibitors. Moreover, we also examined the inhibitory activities of perfluorooctadecanoic acid (PFOdA) and perfluorooctanesulfonic acid (PFOS) against DNApolymerase beta in detail. These compounds inhibited the polymerase activity of pol beta competitively with template-primer DNA, and non-competitively with dNTPs. In addition, the