Despite working multiple hours per day in direct sunlight, U.S. military veterans who were deployed to Iraq and Afghanistan reported limited use of sun protection, found a new study from Vanderbilt University.

Analyzing anonymous survey data from 212 veterans from the post-deployment clinic at the Nashville VA Medical Center, researchers found that 77 percent of respondents spent four or more hours per day working in the sun and 63 percent had at least one sunburn during deployment.

Only 13 percent of participants reported routinely using sunscreen, while 87 percent reported their sunscreen use as “sporadic” or “sometimes.”

“I think we were all somewhat surprised, at first, of how many veterans experience sun burn,” study author Jennifer Powers, assistant professor in the dermatology division at the Vanderbilt School of Medicine, told FoxNews.com, adding that the incidence rate was similar across different skin types and ethnicities.

Researchers also found that participants had lower access to sun protection— including hats, sunscreen, sunglasses, and shade structures—  than the team anticipated. However, when participants had access to sun protection, they were more likely to use it. Additionally, participants who worked over six hours in the bright sun reported they had lower availability to sun protection.

“The study does point out that certainly they’re not using sun protection to the degree we would all like because we know, based on previous historical data, that veterans who have particularly served in very sunny places have higher risks for melanoma later in life,” Powers said.

Applying sunscreen while on duty has challenges, researchers noted.

“I think there’s probably a lot of complicated factors in terms of how to actually put [sun protection] into practice in a very hot environment,” Powers said.

According to a 2011 study published in Cancer Epidemiology, Biomarkers & Prevention,  melanoma incidence had the most rapid increase (40 percent) among younger white men in the military, compared to the general population.

Additionally, a 2014 study published in Military Medicine found melanoma risk was higher among active duty personnel, compared to the general population.

Individuals in the armed services are particularly at risk for melanoma, not only because of increased UV exposure, but also because melanoma cells react aggressively to quick bursts of intense UV light.

“Going from a less equatorial altitude to a much more equatorial altitude quickly over a couple days doesn’t allow your body to habituate to the stress and that’s the kind of quick, abrupt shift we associate more with melanoma than with other skin cancer,” Powers said.

Researchers noted that 80 percent of respondents relied on recall of events which occurred over a year ago.

Moving forward, the team hopes to study a broader population, including Navy and Air Force veterans. Vanderbilt University is located about an hour away from Fort Campbell Army base.

“I think a lot of people today feel a lot of gratitude toward veterans and at the same time we really want to do everything we can to protect them and this is one of those instances where we’re identifying education and protection gaps that hopefully we will act on,” Powers said. “Melanoma is on the rise, more people are dying from it, yet is the number one preventable cancer. This [population] could be subtext of that trend.”

The study was published in the Journal Of Investigative Dermatology.