Genotoxicity assessment of acute exposure of 2, 4-dinitroanisole, its metabolites and 2, 4, 6-trinitrotoluene to Daphnia carinata.

The insensitive munition ingredient, 2, 4-dinitroanisole has emerged as an alternative ingredient to 2, 4, 6-trinitro toluene in melt pourable high explosive formulations mainly due to its improved insensitiveness properties. As a result, production of 2, 4-dinitroanisole has increased and as a consequence 2, 4-dinitroanisole has emerged as a potential ingredient to enter the environment and possibly persist in water and soil ecosystems. The present study showed that 2, 4-dinitroanisole, its metabolites (2-amino 4-nitroanisole and 2,4-dinitroanisole) and 2, 4, 6-trinitro toluene were found to induce DNA damages in a freshwater crustacean Daphnia carinata exposed for 48 h and which was investigated by the alkaline single-cell gel electrophoresis (comet assay) method. The value of LC50-48 h of 2, 4-dinitroanisole was determined as 14.87 ± 1.70 (mg L-1) and its metabolites exhibited the similar toxic range although the toxicity of 2, 4, 6-trinitro toluene was seven-fold more toxic (2.32 ± 0.29 mg L-1) than 2, 4-dinitroanisole and its metabolites. Exposure to sub-acute toxicity concentration ranges of 2, 4-dinitroanisole and its metabolites and 2, 4, 6-trinitro toluene showed significant (P < 0.01) DNA damage. The higher concentration of each test chemical exhibited higher tail DNA per cent and increased olive tail moment. The results from this study can be used to identify genotoxic biomarkers for the risk assessment of insensitive munitions exposure in aquatic invertebrates.