Abstract
Biological monitoring methods have been recommended for 4,4′-methylene bis-(2-chloro-aniline), an animal carcinogen which is absorbed through the skin. An analytical method for this substance in urine which is more sensitive and discriminating than the published method is described. In the new method the material is partially purified by solvent extraction and thin-layer chromatography before it is converted to its trifluoroacetyl derivative and analyzed by gas chromatography. A detection limit of 1 µgL is claimed.