Of the more than 100,000 private contractors ("force multipliers," in military bureaucrat jargon) the U.S. government deployed to the wars in Iraq and Afghanistan, roughly 18,000 were killed or injured. Yet there are thousands of other civilians who work directly under the command of the Department of Defense who have been exposed to the horrors of war. A new study examines the mental health toll on the roughly 6,000 civilians who lived and worked alongside soldiers in Iraq and Afghanistan.

The study, conducted by sociologists Alex Bierman and Ryan Kelty, and published in the most recent issue of Social Psychology Quarterly, is unique because there is a lack of research into mental health issues experienced by civilian employees in the Middle Eastern theater. While the number of suicides among members of the armed services has continued to climb, no agency keeps track of civilian suicides once they return.

Bierman and Kelty surveyed two logistics brigades who had been deployed in Iraq and Afghanistan, and found that they experienced a preponderance of "life threatening hazards," and more than a third of those surveyed said they felt their lives were in danger a few times a month or more.

Civilians may be exposed to IEDs (improvised explosive devices). And rocket or mortar attacks on the bases are not uncommon. The protocol for civilians in these instances is to grab their gear — their Kevlar vests and gasmasks — and head to the designated shelter until they receive further notice. Civilians frequently face this sort of overwhelming threat in their environment.

This stressor is likely to be especially salient for civilians because individuals who are less experienced with war settings have a greater tendency to perceive or recall life-threatening experiences.

Not surprisingly, those civilians who experienced more life-threatening incidents were more prone to feel signs of psychological distress, like depression, anxiety, and anger. As the threats against the civilians increased, their mental health deteriorated.

“It’s important to understand that civilian exposure to life threatening hazards may have long-term mental health effects, and we should be offering support to these people,” Bierman says in a release.