P-Hydroxybenzoic Acid Esters as Preservatives II.:Acute and Chronic Toxicity in Dogs, Rats, and Mice

Abstract

The results of a study of the acute and chronic toxicity of p-hydroxybenzoic acid and the methyl, ethyl, propyl, and butyl esters in mice, rats, and dogs are presented. All of these compounds possess a low order of acute toxicity. The toxicity of the sodium salts appears to be a function of the length of the alkyl substituent, with the butyl ester about three times as toxic as the methyl ester. The main toxic effect is an acute myocardial depression accompanied by hypotension, but this is transient in nature and not cumulative. No evidence of blood damage or histological changes in tissues of treated animals was noted. In concentrations below 5 per cent, none of the esters produces any evidence of primary irritation when applied to the intact skin of man. From the results obtained, it may be concluded that the methyl, ethyl, and propyl esters of p-hydroxybenzoic acid may be used safely as preservatives in effective concentrations for foods and drugs.