American flight attendants have a higher prevalence of several forms of cancer, including breast, uterine, gastrointestinal, thyroid, and cervical cancers, when compared with the general public, according to new research from the Harvard T.H. Chan School of Public Health.
Are flight attendants getting the health and safety protection they deserve?
All workers are entitled to a safe workplace under federal law and the Occupational Safety and Health Administration (OSHA) sets standards and regulations to ensure safe and healthful working conditions. Historically, flight attendants had been excluded from OSHA’s protection and while certain protections have recently been added, they may not necessarily be fully encompassing of all the potential risks to which cabin crewmembers are exposed.
In 2014, OSHA started a monitoring program that focuses on flight attendants’ exposure to noise, hazard communication and blood born pathogens. However, according to the National Council on Radiation Protection (NCRP), flight attendants are exposed to the largest effective dose of ionizing radiation among all workers exposed to radiation due to cosmic ionizing radiation at altitude, and this risk not currently covered under OSHA. This is important because chronic exposure to low doses of ionizing radiation increases the chance of developing cancer over time.
What we found
Our recent study on flight attendant health found that flight attendants have a greater prevalence of cancer when compared to the general public, consistent with previous studies among U.S. and European flight attendants.
The study used an analytical technique that calculated age-weighted standardized prevalence ratios (SPR). Our analysis determined that the SPR is 2.15 for cancer at all sites, which means that there is over 2 times the prevalence of cancer among flight attendants compared to the general public.
The increased exposure to ionizing radiation could play a role in the higher cancer cases seen among flight attendants.
In another soon to be published study, we note that specific cancers that have been linked to flight attendant work include breast cancer, melanoma and non-melanoma skin cancers. While studies have been mixed regarding a relationship between melanoma and ionizing radiation, this form of radiation is considered a risk factor for breast and non-melanoma skin cancers.
Another risk factor for cancer experienced by flight attendants is Circadian rhythm disruption due to irregular and disrupted sleep patterns. Second hand smoke exposure has the possibility of increasing cancer cases among flight attendants as well, but due to a regulation in 1998 that banned smoking on aircrafts, this exposure has been eliminated.
More research is needed, however, this study emphasizes the need for increased attention and monitoring of other potential health hazards, such ionizing radiation, to which flight attendants are more frequently exposed than the general public.
Flight attendants are an understudied occupational group, despite undergoing a wide and unique range of adverse job-related exposures. In our study, we aimed to characterize the health profile of cabin crew relative to the U.S. general population.
In 2014–2015, we surveyed participants of the Harvard Flight Attendant Health Study. We compared the prevalence of their health conditions to a contemporaneous cohort in the National Health and Nutrition Examination Survey (NHANES 2013–2014) using age-weighted standardized prevalence ratios (SPRs). We also analyzed associations between job tenure and selected health outcomes, using logistic regression and adjusting for potential confounders.
Compared to the NHANES population (n = 2729), flight attendants (n = 5366) had a higher prevalence of female reproductive cancers (SPR = 1.66, 95% CI: 1.18–2.33), cancers at all sites (SPR = 2.15, 95% CI: 1.73–2.67 among females), as well as sleep disorders, fatigue, and depression, with SPRs ranging between 1.98 and 5.57 depending on gender and the specific condition examined. In contrast, we observed a decreased prevalence of cardiac and respiratory outcomes among flight crew relative to NHANES. Health conditions that increased with longer job tenure were sleep disorders, anxiety/depression, alcohol abuse, any cancer, peripheral artery disease, sinusitis, foot surgery, infertility, and several perinatal outcomes.
We observed higher rates of specific adverse health outcomes in U.S. flight attendants compared to the general population, as well as associations between longer tenure and health conditions, which should be interpreted in light of recall bias and a cross-sectional design. Future longitudinal studies should evaluate specific exposure-disease associations among flight crew.
Did you ever wonder how your body responds to flight?
We did too! So we built the Flight Health app to understand how flight impacts heart rate and rhythm, cognitive functioning, breathing, oxygen saturation at altitude, and health symptoms.
With today’s availability of wearable technology, we are able to take a more hands-on approach to monitor health symptoms in relation to flight. This means that we will have more real-time data on how flight may affect your health.
The app is available for free for any interested flight attendant, pilot, former crew member, or passenger with an iPhone.
You can download the Flight Health app in the Apple app store. [For now, the Flight Health app is only available to be downloaded to an iPhone.]
Once you download the app and open it, you will be prompted through a series of questions to set up your profile and register. You will also be asked if you agree to have the Flight Health app sync with the Apple Health app that you already have on your phone.
If you’d like to use the app and contribute to our data collection, we recommend that you track flight(s) on your iPhone starting from 2 hours before departure, during the flight, and within 2 hours after landing. Tracking will include answering questions about your health, including sleep quality, and cognitive tests. Each activity should take no more than 5 minutes.
Do you have an Apple Watch?
If you have an Apple Watch, you can also sync the Watch with the Flight Health app. The app itself measures health symptoms, cognitive functioning, and sleep quality through a series of questions and exercises. And the Apple Watch measures your heart rate and rhythm, and physical activity(steps taken). As you enter data pre, during, and post flight, you will see the effects of flight at these stages on your heart rate and rhythm and physical activity via the Apple Health app.
Other optional sensors include a Spire monitor to measure respiration, an iHealth Air pulse oximeter to measure blood oxygenation, and a ResMed S+ sleep monitor to measure sleep quality before flight and during layovers. If you sync all of these devices with the Flight Health app, we will be able to collect this valuable data, and you will be able to track the patterns on the Apple Health app.
Your privacy is of utmost importance to us.
We take great care to protect the privacy of your information. All data is encrypted and transmitted securely to a password protected storage database. Your personal, identifying information (name and email address) will be separated from the rest of your study data. Harvard researchers are trained in handling highly confidential data and will not disclose personal information to anyone at any time without your consent.
You participation adds a wealth of information to the little we currently know about health before, during, and after flying.
Our hope is that this research will shed light on subtle, difficult to detect flight-related changes in health markers, sleep, and mood that could affect the risk of diagnosable health outcomes. Our goal is to distribute the full sensor package to as many flight attendants as possible in future research efforts!
Please spread the word to your friends, co-workers, and union. The more people who volunteer, the greater impact we can make on the flight attendant community and the availability of scientific knowledge for all flight crew and passengers.
Eileen McNeely, Steven J. Staffa, Irina Mordukhovich and Brent Coull
Flight attendants at Alaska Airlines reported health symptoms after the introduction of new uniforms in 2011. The airline replaced the uniforms in 2014 without acknowledging harm. To understand possible uniform-related health effects, we analyzed self-reported health symptoms in crew who participated in the Harvard Flight Attendant Health Study between 2007 and 2015, the period before, during, and after the introduction of new uniforms.
We calculated a standardized prevalence of respiratory, dermatological and allergic symptoms at baseline, as well as during and after uniform changes in 684 flight attendants with a varying number of surveys completed across each time point. We used Generalized Estimating Equations (GEE) to model the association between symptoms at baseline versus the exposure period after adjusting for age, gender and smoking status and weighting respondents for the likelihood of attrition over the course of the study period.
We found the following symptom prevalence (per 100) increased after the introduction of new uniforms: multiple chemical sensitivity (10 vs 5), itchy/irritated skin (25 vs 13), rash/hives (23 vs 13), itchy eyes (24 vs 14), blurred vision (14 vs 6), sinus congestion (28 vs 24), ear pain (15 vs 12), sore throat (9 vs 5), cough (17 vs 7), hoarseness/loss of voice (12 vs 3), and shortness of breath (8 vs 3). The odds of several symptoms significantly increased compared to baseline after adjusting for potential confounders.
This study found a relationship between health complaints and the introduction of new uniforms in this longitudinal occupational cohort.
What this paper adds
We know little about the health effects of chemicals in our clothing as compared to substances we ingest, even though skin absorption can be quite efficient and researchers have found metals, dyes, formaldehyde and formaldehyde releasers, dioxin, perfluorinated compounds, flame retardants, phthalates and other plasticizers such as diisodecyclmaleate, pesticides and fungicides in clothing.
This study offers a unique window into the potential health effects of textile chemicals after the introduction of new work uniforms in an occupational cohort– a rare opportunity to appreciate a common exposure in a defined population with a specific release date.
We found significantly increased prevalence of symptoms after the introduction of new uniforms including eye pain/dry eyes/itchy eyes, blurred vision, combined EENT, cough, hoarseness/loss of voice combined lower respiratory, itchy/irritated skin, and rash/hives.
These findings together with reports of similar health reactions in yet another U.S. flight attendant population after the introduction of new uniforms this year warrants further investigation of the specific chemical toxicants, clothing concentrations, body burdens and health effects.
Dear Flight Attendants,
Our researchers will be at Chicago O’Hare this Saturday to Monday to get word out about our survey and sensor study!
Visit us at Chicago O’Hare
Saturday 2/17 through Monday 2/19
We will be splitting our time between Terminals 1 and 3
We are looking forward to seeing and talking to Flight Attendants at these airports!
Come say hi and talk to us about our study!
As researchers, we are constantly thinking of new ways to gather real-time data to help illuminate how the working environment affects the health of flight attendants.
With today’s availability of wearable technology, we are able to take a more hands-on approach to monitor health symptoms in relation to flight. This means that we are aiming to measure participants’ real-time flight experience using wearable sensors, such as Apple watches, in conjunction with a mobile FlightHealth app.
Specifically, we are developing an app, to be released in February, that we will distribute along with wearable sensors to a small subset of Flight Attendant Health Study participants. The app will also be available for free on our website for any interested flight attendant, pilot, former crew member, or passenger with an iPhone and any series of Apple watch. For people downloading the app from our website, optional sensors include a Spire monitor to measure respiration, an iHealth Air pulse oximeter to measure blood oxygenation, and a ResMed S+ sleep monitor to measure sleep quality during layovers.
Our hope is that this research will shed light on subtle, difficult to detect flight-related changes in health markers, sleep, and mood that could in turn potentially increase the risk of adverse health outcomes. Our goal is to leverage our initial findings to distribute the full sensor package to as many flight attendants as possible in future research efforts!
Feel free to spread the word to your friends, co-workers, and union. The more people who volunteer, the greater impact we can make on the flight attendant community and the availability of scientific knowledge for all flight crew and passengers.