Abstract

Sustainable use of training ranges requires the development of compounds that have a minimal impact on the environment when used in a weapon system.  Triaminoguanidinium-1-methyl-5-nitriminotetrazolate (TAG-MNT) is a novel, explosive, military compound of interest for application in some weapon systems.  Little is known of its toxicologic properties.  To ensure the health of potentially exposed personnel and the environment, several initial toxicity investigations were conducted and the results compared with another widely used energetic (hexahydro-1,3,5-trinitro-1,3,5-triazine; RDX). In a novel microplate Ames assay, TAG-MNT was a weak mutagen only at the limit concentration of 2 g/L.  However, TAG-MNT was cytotoxic to bacteria and a human liver cell line at 250 mg/L and greater. Unlike RDX, TAG-MNT did not have an affinity for the GABAa receptor convulsant site, and was predicted not to induce seizure. After acute oral dosing in female rats, TAG-MNT had no apparent adverse effect up to the limit dose of 2 g/kg. However, daily oral dosing for 14 days at exposures of 1000 mg/kg-d and above caused reduction in food intake, weight loss, increased kidney weight, leucopenia, and elevated blood urea nitrogen and creatinine levels. Leucopenia, increased liver mass, evidence of liver hepatocyte necrosis and centrilobular hypertrophy were observed at 500 mg/kg-d and above. TAG-MNT was negative in the rat micronucleus assay of blood samples. Based on these data, the 14-day oral No observed adverse effect level (NOAEL) and the lowest observed adverse effect level (LOAEL) is 250 and 500 mg kg^-lday^-1, respectively. 

Key words: RDX, Ames assay, cytotoxicity, oral toxicity, rat micronucleus assay.