This document is a method for determining the total content (solvent extractible) of the following bisphenols in leather: bisphenol A; bisphenol B; bisphenol F; bisphenol S. This method requires the use of liquid chromatography (LC) with triple quadrupole mass spectrometer (MS/MS) or with ultraviolet (UV) detector or with Diode Array Detector (DAD) or with Fluorescence Detector (FLD) to identify and quantify the bisphenols. NOTE 1 This method can also be used for other bisphenols if they are validated by the laboratory. NOTE 2 The main difference between LC-MS/MS and LC-UV, LC-DAD or LC-FLD is the quantification limit (9.2).