NIOSH Worker Health Study Summaries - Flight Attendant Other Cancers

 A Study of Cancer in Female Flight Attendants:  2018 Update

What we found
  • Work-related exposures to cosmic radiation and circadian disruption were not linked to skin melanoma, thyroid cancer, cervical cancer, uterine cancer, or ovarian cancer.
  • Women in our study were not more likely to get thyroid cancer, uterine cancer, or ovarian cancer than women in the general population.

About the Study

The National Institute for Occupational Safety and Health conducted this study to look at several types of cancer, especially breast cancer, among women who had worked as flight attendants at Pan Am.  We previously reported the breast cancer resultsCdc-pdf.  The purpose of this summary is to report the results for five other cancers – skin melanoma, thyroid cancer, cervical cancer, uterine cancer, and ovarian cancer.

We looked at skin melanoma, thyroid cancer, cervical cancer, uterine cancer, and ovarian cancer because

  • an increased melanoma risk has been observed in other studies of aircrew, but the reason for the excess is unclear,
  • some thyroid cancers are caused by ionizing radiation, and
  • reproductive cancers may be caused by circadian rhythm disruption from effects on reproductive hormones or other effects.

Study goals

The main goals were to learn:

  1. Whether skin melanoma, thyroid cancer, cervical cancer, uterine cancer, and ovarian cancer are linked to work-related exposure to cosmic radiation or circadian disruption, and
  2. If women who worked as flight attendants at Pan Am were more likely to be diagnosed with thyroid cancer, uterine cancer, or ovarian cancer than women in the general population.  We were not able to learn whether women who worked as flight attendants at Pan Am were more likely to be diagnosed with skin melanoma or cervical cancer because we did not have comparable data on rates of these cancers among women in the general population.
Key Terms

Circadian Disruption: disruption in a person’s internal biological clock that regulates the release of hormones and other changes in body function over a roughly 24-hour cycle. Aircrew may experience circadian disruption (specifically, jet lag) when they travel across time zones and work when others would normally be asleep. The International Agency for Research on Cancer (IARC) has determined that circadian disruption probably causes cancer.

Cosmic Radiation: a form of ionizing radiation that comes from outer space. A very small amount of this radiation reaches the earth. At flight altitudes, passengers and aircrew are exposed to higher levels of cosmic radiation.

We also collected data on some other types of cancer, such as brain cancer, leukemia, and lung cancer.  We did not evaluate the risk of brain cancer or leukemia because there were not enough women in the study diagnosed with these cancers for us to be able to examine them.  We did not evaluate lung cancer risk because we do not have data to differentiate women in the study by level of exposure to environmental tobacco smoke on aircraft.

Frequently Asked Questions (FAQs)

Q:  What factors did you take into account when you looked at whether skin melanoma, thyroid cancer, cervical cancer, uterine cancer, or ovarian cancer were linked to work-related exposure to cosmic radiation or circadian disruption?
A:  The factors we took into account varied depending on the type of cancer.

  • For all five of these cancers we took into account age and race.
  • For skin melanoma and thyroid cancer we also took into account year of birth and education.
  • For cervical cancer we also took into account year of birth, education, parity (the number of times a woman has given birth), and age at first birth.
  • For uterine cancer we also took into account hormone replacement therapy, parity, and age at first birth.
  • For ovarian cancer, we also took into account parity and age at first birth.

Q:  What factors did you take into account when you looked at whether women in the study were more likely to be diagnosed with thyroid cancer, uterine cancer, and ovarian cancer than women in the general population?
A:  We took into account differences in age, race, and year of birth between women in the study and women in the general population.

For answers to other frequently asked questions, please see Frequently Asked Questions: A Study of Breast Cancer in Flight AttendantsCdc-pdf

For more information

Pinkerton LE, Hein MJ, Anderson JL, Christianson A, Little MP, Sigurdson AJ, Schubauer-Berigan MK. (2018) Melanoma, thyroid cancer, and gynecological cancers in a cohort of U.S. flight attendants. American Journal of Industrial Medicine. In Press.

Pinkerton LE, Hein MJ, Anderson JL, Little MP, Sigurdson AJ, Schubauer-Berigan, MK. (2016). Breast cancer incidence among female flight attendants: exposure–response analyses. Scandinavian Journal of Work, Environment & Health, 42(6), 538-546.

Schubauer‐Berigan MK, Anderson JL, Hein MJ, Little MP, Sigurdson AJ, Pinkerton LE. (2015). Breast cancer incidence in a cohort of US flight attendants. American Journal of Industrial Medicine, 58(3), 252-266.

Pinkerton LE, Waters MA, Hein MJ, Zivkovich Z, Schubauer‐Berigan MK, Grajewski B. (2012). Cause‐specific mortality among a cohort of US flight attendants. American Journal of Industrial Medicine, 55(1), 25-36.

Study Summary: A Study of Breast Cancer in Flight Attendants https://www.cdc.gov/niosh/pgms/worknotify/pdfs/FABC-summary-04-03-17-508.pdfCdc-pdf

Frequently Asked Questions: A Study of Breast Cancer in Flight Attendants https://www.cdc.gov/niosh/pgms/worknotify/pdfs/FABC-FAQs-05-03-17-508.pdfCdc-pdf

To learn more about aircrew safety and health and ways to stay healthy, visit the NIOSH Aircrew Safety & Health topic page at www.cdc.gov/niosh/topics/aircrew/ .

Page last reviewed: May 16, 2018