This volume contains critically assessed data and recommendations for occupational safety officers, industrial hygienists, and human and animal toxicologists. The facts are compiled and reviewed under internationally co-ordinated programmes for establishing the risk potential of existing chemicals to prevent health hazards at the working place. Information on the following chemicals is presented: monochloroacetic acid, benzene sulphonic acid hydrazide, 1,3-dio-tolylguanidine, 4-nitrophenol, 2-methyl-3-butyn-2-ol, n-carboxyanthranilic acid anhydride, propionaldehyde, azodicarbonamide, isobutylidenediurea, hydroxylamine and its salts, and zinc ethylphenyldithiocarbamate.