Formation of mutagens from the aqueous reactions of ozone and anilines

Abstract

Azobenzenes, azoxybenzenes and benzidines were the products of interest obtained from the aqueous reactions of anilines with ozone. The reaction mechanisms for their formation are discussed. Conditions favoring ozone decomposition and the presence of carbonate species increased the yield of these polyaromatic nitrogen compounds. Fulvic acid inhibited the formation of azobenzene without decreasing the amount of aniline degraded. The effects of pH and inorganic buffers on the formation of N-substituted polyaromatic compounds from aniline can be explained by the decomposition of ozone by OH − and OOH −, scavenging of the hydroxyl radical and suppression of ozone decomposition by carbonate species, and selective oxidation of aniline by carbonate radicals.