A gas chromatographic procedure is described for the quantitative determinations of ethylene chlorohydrin and ethylene glycol in disposable medical‐grade plastics. Both components are isolated by solvent extraction. The lower limit of detection is 1 p.p.m. of ethylene chlorohydrin and 2 p.p.m. of ethylene glycol. Propylene glycol is used as an internal standard. Ethylene oxide residues have to be removed prior to the assay.