Pilots and cabin crews face twice the risk of suffering from the type of skin cancer known as melanoma, according to a new study by University of California, San Diego.

The researchers said that flight-based workers experience a heightened occupational hazard risk of melanoma because of increased altitude-related exposure to Ultra Violet and cosmic radiation.

Dr. Susana Ortiz-Urda, co-director of the UCSF Melanoma Center, urged airlines to select windows that offer more protection against UV rays. "More measurements should be performed by the Federal Aviation Administration in regards to cumulative UV exposure for pilots and cabin crew, cbc news reports."

According to the American Cancer Society (ACS), almost 10,000 people will die of melanoma in 2014, and over 76,000 people will be diagnosed with the illness.

Previous studies showed the risks of exposure to ionizing radiation for pilots and cabin crew. However, UV exposure as an occupational risk factor for the flight crew has not been very well-studied.

For the studies, the researchers analysed the risk of melanoma in pilots and airline crew by conducting a meta-analysis of 19 studies with over 266,000 participants. They found that the overall summary standardized incidence ratio (SIR) of melanoma for any flight-based occupation was 2.21, the summary SIR for pilots was 2.22 and 2.09 for cabin crew.

"In this systematic review and meta-analysis including 19 studies and more than a quarter of a million participants, we found that the combined and separate SIRs for pilots and cabin crew were greater than the 2, indicating that pilots and air crew have twice the incidence of melanoma compared with the general population. ... This has important implications for occupational health and protection of this population," researchers said in a press release.

The study, however, did not determine whether exposure to the sun during flight time is responsible for the increased risk. Plus, no evidence relating extra flying time to these cancers was also not found.

Eero Pukkala, a Finnish researcher, said that frequent travel to sunny climates and sun-tanning by pilots and cabin crew members can partially explain the higher risk.