Sentinel role of military dogs in detecting genotoxic agents in the environment during military operations: a pilot study.

During out-of-area military operations, the presence of carcinogenic and/or genotoxic agents has been reported, posing potential health risks to deployed soldiers. Military working dogs (MWDs), trained to detect explosives in the same environments as soldiers, could also serve as sentinel animals, providing valuable information on exposure to hazardous agents. These dogs can help identify environmental and potential adverse effects on their health and that of their handlers, possibly before relevant pathologies manifest. This study aims to evaluate the effectiveness of 33 Italian Army MWDs, deployed to the Lebanese theater for six consecutive months from October 2013 to January 2015, as sentinel animals for detecting exposure to genotoxic agents. The Cytokinesis-Block MicroNucleus (CBMN) assay was used to assess DNA damage, cytostasis, and cytotoxicity in the lymphocytes of these dogs. DNA damage events were specifically scored in once-divided binucleated cells (BCs) and included: a) micronuclei (MNi), indicative of chromosome breakage and/or whole chromosome loss; b) nucleoplasmic bridges (NPBs), a marker of DNA misrepair and/or telomere end-fusions; and c) nuclear buds (NBUDs), which signal the elimination of amplified DNA and/or DNA repair complexes. Our findings revealed an increase in chromosomal damage, assessed before and after deployment, with a statistically significant rise in MNi frequency, thus supporting the use of MWDs as sentinels for human exposure to hazardous agents.