Toxicity of and biological monitoring for 1,3-diamino-2, 4, 6-trinitrobenzene and other nitro-amino derivatives of benzene and chlorobenzene

Summary Methaemoglobin-forming capacity of 1,3-diamino-2,4,6-trinitrobenzene (DATNB) was studied in vivo as well as in vitro and compared with those of aniline, phenylenediamine (o- and p-), nitroaniline (o-, m- and p-), nitrobenzene, dinitrobenzene (o-, m- and p-), 1,3,5-trinitrobenzene, chloroaniline (o-, m- and p-), chloronitrobenzene (o-, m- and p-), and 1-chloro-2,4-dinitrobenzene. m-Chloronitrobenzene and two isomers (m- and p-) of dinitrobenzene were the most potent methaemoglobin formers in vivo and it was p-dinitrobenzene when studied in vitro, while the capacity of DATNB was much lower both in vivo and in vitro, being comparable to those of aniline and nitrobenzene. The exposure monitoring by means of the urinalysis for diazo-positive metabolite(s) is applicable to all the compounds studied except DATNB and o-phenylenediamine; conversion of DATNB to the diazo-positive metabolite(s) in urine was very limited, indicating poor metabolism in vivo. Cumulative effects of DATNB was also discussed.This work was supported in part by a research grant from Environment Agency, the Government of Japan