From Blast to Biological Uptake: Residual Dinitrotoluene as an Occupational Exposure Hazard in Explosive Ordnance Disposal.

Repeated mixed-munition demolition may require explosive ordnance disposal personnel to re-enter a common demolition pit to inspect effects, recover debris and prepare subsequent stacks. Dinitrotoluene (DNT) is a recognised explosive ordnance occupational toxicant absorbed by inhalation, skin and ingestion. Urinary-tract malignancies and other adverse outcomes have been reported in highly exposed nitroaromatic-explosives workers. Recently, bladder-cancer incidence was documented as elevated among former British Army ammunition technicians. While these observations do not establish a causal relationship with DNT, they however provide a strong rationale for further investigation of credible exposure pathways. This study developed a scenario-based source-pathway-receptor model to examine whether residual DNT could constitute an occupational exposure source during these tasks. This model was applied to an explosive ordnance disposal operation involving 20 sequential demolitions and a documented aggregate TNT-equivalent basis of 1000 kg, used as a screening proxy because the operational inventory was predominantly TNT-filled. The model identified plausible primary inhalation from a blast-generated plume and secondary inhalation from resuspended residues, together with dermal and incidental-ingestion pathways. An important caveat is that it does not reconstruct individual dose or establish disease causation. Validation requires time-resolved post-blast and task-based personal air sampling, surface assessment, biomonitoring and detailed exposure reconstruction during representative demolition operations. As such, this study establishes crucial foundational hypotheses for future occupational hazard research into DNT exposure to explosive ordnance disposal personnel.