The "Toxicological Evaluations" are critically assessed data and recommendations for occupational safety officers, industrial hygienists, and human and animal toxicologists. They are compiled and constantly reviewed under internationally co-ordinated programmes for establishing the risk potential of existing chemicals to prevent health hazards at the working place. Up to now 61 chemicals have been published in the series. In this fifth volume, data for the following 12 chemicals are published: 4,4-methylene-bis (2,6-di-t-butylphenol), dioctyldiphenylamine, 1-chloro-2,4-dinitrobenzene, p-tert-butylbenzoic acid, ethyl diglycol, vinyl methyl ether, sodium aluminium hexafluoride (cryolite), sulphuryl chloride, chloroacetic acid ethyl ester, diphenyl cresyl phosphate, p-aminodiphenylamine and trimethylhydroquinone.