This document specifies a method for determining the total content (solvent extractable) of the following bisphenols in chemicals for the leather tanning industry: —     bisphenol A; —     bisphenol AF; —     bisphenol B; —     bisphenol F; —     bisphenol S. This method requires the use of liquid chromatography (LC) with either a single quadrupole mass spectrometer (MS), a triple quadrupole mass spectrometer (MS/MS), an ultraviolet (UV) detector, a diode array detector (DAD) or a 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        Bisphenol S cannot be detected with FLD.