Toxic Polyneuritis arising during Manufacture of Tricresyl Phosphate

Abstract

This communication records the toxic effects caused by tri-ortho-cresyl phosphate in three men employed in its manufacture. Tricresyl phosphate is used in the recovery of phenol residues from gas plant effluents and also as a plasticizer in the plastics industry. A plasticizer is a substance used to render a plastic material more pliable, and by alteration of the amount of the plasticizer added, such characteristics as flexibility, hardness, water resistance and inflammability can be varied between wide limits. In this industry it is being used in increasing quantities, for example, as much as 50 per cent, of tricresyl phosphate is sometimes added to polyvinyl chloride. Tricresyl phosphate used in industry is an oil with a slightly pungent odour: of the three isomerides the orthoand metaare liquids, and the parais a crystalline solid. Indus trial tricresyl phosphate is prepared by treating cresols with phosphorus oxychloride in the presence of an aluminium catalyst. It has been the boast of industry in the United States of America that in a plant manufacturing 100,000 lb. of this material a day without any special precautions no cases of poisoning have occurred. However, since 1939 black-out regulations in Great Britain, imposed as a precaution against air attack, have led to a less fortunate state of affairs, and three workmen employed in a manufacturing plant have developed polyneuritis. As a result of these cases poisoning by tricresyl and triphenyl phosphate resulting from the manufacture or use of these products in industry was scheduled under the Workmen's Compensation (Industrial Diseases) Order, 1942, No. 1326.