Pentagon needs more resources to monitor blast-exposed troops’ brain health, GAO finds

Pentagon efforts to monitor the impact of blasts on service members’ brain health have improved in recent years, but programs meant to track their exposure and catch potential cognitive changes are under-resourced, according to a new Government Accountability Office report.

Nearly all new service members who entered the military in fiscal year 2025, almost 200,000 troops, completed baseline cognitive testing meant to help clinicians identify potential mental changes after service members are exposed to certain weapons. But funding and personnel constraints have slowed the full implementation of recent efforts to monitor weaponry’s impacts on troops’ brain health, the government watchdog found in the report published Tuesday.

“There’s growing evidence that service members’ brain health may be at risk due to blast exposures from certain weapons they fire during training or combat,” the GAO report reads. “Firing these weapons can expose service members to blast overpressure waves, which may cause problems such as headaches, memory loss, or traumatic brain injury.”

The Pentagon in 2024 set a goal to ensure cognitive testing for all incoming recruits and current service members working in specialties identified as most likely to face blast exposure by Sept. 30, 2025. New troops take the cognitive test within days of arriving at their initial entrance training location before they are exposed to any military weaponry.

As of October 2025, only about 86% of active-duty troops in such high-risk roles had received their baseline testing, GAO found.

GAO analysts recommended the Pentagon launch a full assessment of the resources it needs to implement cognitive testing for high-risk troops at least once every five years and to improve efforts to track all the blasts those troops are exposed to in training and combat. Pentagon officials said they agreed with the GAO recommendations and have begun new programs aimed at improving those efforts.

In 2022, Defense Department officials found that troops exposed to blast overpressure of 4 pounds per square inch were more likely than others to experience brain injuries. The Pentagon found shoulder-fired weapons, .50 caliber rifles and machine guns, breaching explosives, and indirect fire systems such as cannons and mortars exposed troops to those blast levels when they fired them.

They mandated those who routinely use such weaponry — including those in front-line fighting jobs, special operations, explosive ordnance disposal and weapons instructors — receive routine cognitive testing to monitor the impacts of using those weapons on brain health.

The military departments and the Defense Health Agency told GAO that they needed more funding and personnel to improve the efforts to monitor brain health. The services are supposed to implement cognitive tracking for all troops “as soon as possible,” which will require testing tens of thousands of additional service members.

One issue the officials raised with GAO was a shortage of personnel to conduct the cognitive assessments, which are done via a computer program. DOD this year launched a pilot program that allows service members to complete cognitive assessments themselves via a web application, which Pentagon officials said “could mitigate some of the resource challenges” the program has faced.

GAO also reported a shortage of industrial hygienists, who are responsible for maintaining records of troops’ blast exposures.

The military has tasked its industrial hygienists with tracking when, where and with what weapon a service member is exposed to a blast and gathering blast strength data via sensors. GAO found that the Pentagon did not provide DHA — which oversees DOD’s industrial hygienists — with new funding for the blast overpressure tracking program even after the agency requested more funding.

“Insufficient industrial hygienists are the primary barrier to DOD achieving its targets for exposure tracking,” GAO concluded.

Pentagon officials said they had embarked on an “enterprise-wide assessment of industrial hygiene staffing resources” this year and a large-scale effort to assess the requirements to track service members’ blast exposures. Those efforts are expected to be completed by December, according to the Defense Department.