log Pow values in the range -2 to 4 (occasionally up to 5 and more)1 can be experimentallydetermined by the Shake-Flask method (OECD Test Guideline 107). The HPLC method covers log Pow inthe range of 0 to 6 (1)(2)(3)(4)(5). This method may require an estimation of Pow to assign suitablereference substances and support any conclusions drawn from the data generated by the test. Calculationmethods are briefly discussed in the Annex to this Guideline. The HPLC operation mode is isocratic