Neurological Effects of Repeated Exposure to Military Occupational Levels of Blast: A Review of Scientific Literature

Abstract

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Potential Health and Performance Effects of High-Level and Low-Level Blast: A Scoping Review of Two Decades of Research

“…The intention of this review was to provide a summary of the literature that had been made publicly available to researchers and medical providers, both within and outside of the DoD, rather than including additional reports that may be limited to only DoD personnel. For further information on such studies (including work currently in progress), interested readers are referred to the summary provided by Simmons et al ( 81 ).…”

“…To offset this limitation, we intentionally used search terms that were not limited to purely LLB. Unlike other recent reviews of LLB ( 81 , 82 ), our review evaluated the title and abstract of nearly 5,600 articles investigating blast to identify those that were relevant to LLB. Because of the lack of consistency in the terminology used to describe LLB within the scientific community, this was the only way to ensure that all relevant articles were captured in our review.…”

Blast in Context: The Neuropsychological and Neurocognitive Effects of Long-Term Occupational Exposure to Repeated Low-Level Explosives on Canadian Armed Forces' Breaching Instructors and Range Staff

“…These studies used tasks that are laboratory versions of what is tested with BrDI, and support the scientific concept underlying the unique nature of this approach ( 52 – 57 ). Although no previous human studies in military blast have specifically examined this functional measure, a considerable body of work suggests that there is a unique additive value to including tasks that measure cognitive-motor integration in studies of the effects of blast exposure ( 12 , 37 ).…”

“…However, we do hope that our findings will motivate longitudinal studies that are better suited for isolating the effects of long-term occupational exposure to repeated low-level blast in operators [see Kamimori et al ( 21 )]. Third, because the precise mechanism(s) underlying blast-related neurological injury remains unknown, additional work on that fundamental problem is necessary for gaining a better understanding of the injury pathway ( 12 , 37 ). Fourth, our sample reflects an armed forces population that is mostly male, and as such the findings may not be entirely representative of females ( 63 – 66 ).…”

“…Although the precise nature of the relationship between long-term exposure to repetitive low-level blast and human health remains unknown (11)(12)(13), data suggest that long-term exposure to blast events can have adverse effects on the nervous system (14,15), and can be associated with alterations in cerebral metabolism, diffuse white matter disruption, chronic neuroinflammation (16,17), or perturbations to circulating levels of neurological injury biomarkers (8,(18)(19)(20)(21). Indeed, a major theme in the literature revolves around whether blast injuries represent a different mechanism of injury than accelerationdeceleration injuries, by virtue of their physical dynamics.…”