Two adsorption/microcoulometric methods have been investigated for total organic halogen (TOX) in water. TOX, a proposed water-quality parameter, is a rapid, surrogate method to detect halides microcoulometrically and does not require compound identification before water quality can be judged. An XAD resin is used to concentrate organic halides that are eluted by a two-step, two-solvent procedure, followed by analysis using :chromatography or pyrolysis to convert organic halides to halide. In the granular activated carbon (GAC) method, the entire GAC-organic halide sample is pyrolyzed. TOX measurements of model compounds are comparable by both methods, but GAC was found to be superior to XAD for adsorption of chlorinated humics in drinking water and chlorinated lake water.