Hydrogen, hydrogen sulphide, mercaptoethanol disulphide, and ethanol yields from the radiolysis of 2-mercaptoethanol are consistent with the same mechanism postulated for other sulphydryl-containing molecules. In all cases studiedgHin neutral solution appears to be enhanced (gH = 0.7–0.9 molecule per 100 eV). However, there is no basis for attributing this to reaction [10] which was postulated in earlier work:but is not supported by independent data from H atom studies.