Health Risks of Aircraft Noise

As flight travel becomes more prevalent, communities have started to feel the effects of these loud aircrafts. A recent article in the Los Angeles Times highlights the impacts of flight noise on communities and how citizens can work with government officials to minimize the noise impacts. Jet Blue has taken notice of how loud noise from these jets can negatively impact communities by airports so they are retrofitting their Airbus fleet to make the aircraft quieter. This is a win for individuals on the ground, but in-flight noise is still a concern among pilots, flight attendants, and passengers.

Sound is considered a pollutant according to OSHA. It has the ability to cause physiological stress, cardiovascular disease, hypertension, and disruption of job performance.  and which means there are standards noise must comply with. Currently, the noise standard in the work place is 85 decibels over an 8-hour period. OSHA’s jurisdictions do not extend to aircraft cabins which is currently regulated by the FAA. The FAA has given OSHA permission to regulate aircraft cabin noise. Figure A shows regulations and standards set in place. Together OSHA and the FAA have been working together to keep noise standards under 85dB but there are still a few shortcomings that can be addressed to better protect pilots, flight attendants, and passengers in flight.

As flight technology advances, flight range increases with flights exceeding 17 hours. Since protective standards set in place by OSHA have a limit of 90db, exposure over this time can be damaging to one’s health. A study done by Zevitas et. al. shows that sound levels in airplane cabin during flight range from 38db to 110db. Once sound levels reach 90db, a protective program should be put in place but so far there is no mandatory protection plan for pilots, flight attendants, and passengers. More research on airplane cabin noise and aircraft retrofitting should be done to lower potential flight-related health risks.

Figure A: Noise standards in the workplace

Figure A: Noise standards in the workplace

Figure A

Harvard Researchers Taking on FA Exposure to Radiation

The Occupational Safety and Health Administration (OSHA) sets standards and regulations to protect worker health. Historically, flight attendants had been excluded from OSHA’s protection.  In 2014, OSHA started a monitoring program that focuses on flight attendants’ exposure to noise, hazard communication and bloodborne pathogens (1), but not ionizing radiation. However, according to the National Council on Radiation Protection (NCRP), flight attendants are exposed to the largest effective dose among all US radiation workers due to cosmic ionizing radiation at altitude (2). Chronic exposure to low doses of ionizing radiation increases the chance of developing cancer over time.

Our recent study on flight attendant health found that flight attendants have a greater prevalence of cancer when compared to the general public (3), consistent with previous studies among U.S. and European flight attendants. The study used an analytical technique that calculated age-weighted standardized prevalence ratios (SPRs), and found an SPR of 2.15 for cancer at all sites.  This shows that there is over 2 times the prevalence of cancer among flight attendants compared to the general public, which is important to know because ionizing radiation could play a role in the increased cancer cases seen among flight attendants. 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.

Works Cited

  1. Occupational Safety and Health Administration. Applicability of certain OSHA standards to cabin crew members on Aircraft in Operation (2014). Accessed 27 March 2018.
  2. National Council on Radiation Protection and Measurements. Ionizing radiation exposure of the population of the United States. Report No. 160. In: Recommendations of the National Council on radiation protection and measurements (NCRP). Bethesda, MD: National Council on Radiation Protection and Measurements; 2009. Accessed 27 March 2018.
  3. Estimating the health consequences of flight attendant work: comparing flight attendant health to the general population in a cross-sectional study

 

 

 

CIRCADIAN RHYTHMS

Measuring and identifying large-study metrics for circadian rhythm disruption in female flight attendants

5/29/2003

Grajewski, Nguyen, Whelan, Cole, Hein

Objectives:
Flight attendants can experience circadian rhythm disruption due to travel through multiple time zones. The objectives of this study were to determine whether flight attendants are more likely than teachers (comparison group) to experience circadian disruption, as measured by melatonin production, and to identify metrics of circadian disruption for epidemiologic studies of reproductive health in which biomonitoring is infeasible.

Methods:
Each day, for one menstrual cycle, 45 flight attendants and 26 teachers kept a daily diary, collected and measured their overnight urine, and wore an activity monitor to assess sleep displacement. The relation between melatonin production and flightattendant and teacher status was analyzed with linear and multiple logistic regression. The relation between sleep displacement, melatonin, and flight-history-derived variables (including time zones crossed) were examined with exploratory factor analyses.

Results:
Flight attendants experience increased circadian disruption, as measured by a higher adjusted melatonin rate variance, than teachers [2.8 x 10(5) versus 1.0 x 10(5) (ng/hour)2, respectively: P=0.04] and are more likely to be in the highest quartile of melatonin variance (odds ratio 2.3; 95% confidence interval 0.6-9.1). In the factor analysis, the number of time zones crossed was related to both melatonin desynchronization and sleep displacement.

Conclusions:
Flight attendants experience increased circadian disruption, as measured by more variable melatonin rates, than a minimally flying comparison group. For epidemiologic studies of flight crews in which melatonin measurement is infeasible, the number of time zones crossed is a useful indicator of both sleep displacement and melatonin desynchronization.

http://www.sjweh.fi/show_abstract.php?abstract_id=740

Endometriosis

Lifetime occupational history and risk of endometriosis

Marino, Holt, Chen, Davis

4/17/2007

publications
Abstract
Background:
Endometriosis is the presence of functioning endometrial glands and stroma outside the uterine cavity, most often in the pelvic peritoneal cavity. Women with endometriosis commonly have dysmenorrhea, dyspareunia, pain, menorrhagia and/or metrorrhagia; disease complications can include adhesions, chronic pain, and infertility. This exploratory case-control study investigated the relationship between lifetime occupational history and surgically confirmed endometriosis in a population-based sample.
Methods:
Interviews were conducted with cases, all reproductive-aged female enrollees of a large health-maintenance organization first diagnosed with surgically confirmed endometriosis between April 1, 1996 and March 31, 2001 and randomly selected controls from the reproductive-aged female enrollee list from the same time period. Each reported job was coded using US Census Occupations and Industries codes, and jobs were classed into categories. Having ever worked an occupation in a given job class was compared to never having done so using unconditional logistic regression.Results:
Having ever worked as a flight attendant, service station attendant, or health worker, particularly as a nurse or health aide, was associated with increased risk of endometriosis (flight attendant: OR 9.80, 95% CI 1.08 – 89.02; service station attendant: OR 5.77, 95% CI 1.03 -32.43; health worker: OR 1.49, 95% CI 1.03 – 2.15). Income and education did not make a difference in the odds ratio estimates for the occupations examined.

Conclusion:
This exploratory study suggests that having ever worked as a flight attendant, service station attendant, or health worker, particularly as a nurse, may be associated with an increased risk of endometriosis

 

breast cancer

Risk factors for breast cancer, including occupational exposures

Elisabete Weiderpass, Margrethe Meo, and Harri Vainio

3/02/2011

The knowledge on the etiology of breast cancer has advanced substantially in recent years, and several etiological factors are now firmly established. However, very few new discoveries have been made in relation to occupational risk factors. The International Agency for Research on Cancer has evaluated over 900 different exposures or agents to-date to determine whether they are carcinogenic to humans. These evaluations are published as a series of Monographs (www.iarc.fr). For breast cancer the following substances have been classified as “carcinogenic to humans” (Group 1): alcoholic beverages, exposure to diethylstilbestrol, estrogen-progestogen contraceptives, estrogen-progestogen hormone replacement therapy and exposure to X-radiation and gamma-radiation (in special populations such as atomic bomb survivors, medical patients, and in-utero exposure). Ethylene oxide is also classified as a Group 1 carcinogen, although the evidence for carcinogenicity in epidemiologic studies, and specifically for the human breast, is limited. The classification “probably carcinogenic to humans” (Group 2A) includes estrogen hormone replacement therapy, tobacco smoking, and shift work involving circadian disruption, including work as a flight attendant. If the association between shift work and breast cancer, the most common female cancer, is confirmed, shift work could become the leading cause of occupational cancer in women.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3431884/pdf/shaw-2-1.pdf

respiratory

Associations between respiratory illnesses and secondhand smoke exposure in flight attendants: A cross-sectional analysis of the Flight Attendant Medical Research Institute Survey

Alexis L Beatty, Thaddeus J Haight, and Rita F Redberg

9/24/2011

publications
Abstract
Background:
Secondhand tobacco smoke (SHS) is associated with increased risk of respiratory illness, cancer, and cardiovascular disease. Prior to smoking bans on airlines in the late 1980s, flight attendants were exposed to a significant amount of SHS. In the present study, we examine associations between flight attendant SHS exposure and development of respiratory illnesses and cardiovascular disease.Methods:
Between December 2006 and October 2010, three hundred sixty-two flight attendants completed an online questionnaire with information regarding experience as a flight attendant, medical history, smoking history, and SHS exposure. Rates of illnesses in flight attendants were compared with an age and smoking history matched population sample from NHANES 2005-2006. Logistic regression analysis was used to examine the association of reported medical conditions and pre-ban years of exposure.Results:
Compared with the sample from NHANES 2005-2006, flight attendants had increased prevalence of chronic bronchitis (11.7% vs. 7.2%, p < 0.05), emphysema/COPD (3.2% vs. 0.9%, p < 0.03), and sinus problems (31.5% vs. 20.9%, p < 0.002), despite a lower prevalence of medical illnesses including high blood pressure, diabetes, high cholesterol, heart failure, cancer, and thyroid disease. Amongst flight attendants who reported never smoking over their lifetimes, there was not a significant association between years of service as a flight attendant in the pre-smoking ban era and illnesses. However, in this same group, there was a significantly increased risk of daily symptoms (vs. no symptoms) of nasal congestion, throat, or eye irritation per 10-year increase of years of service as a flight attendant prior to the smoking ban (OR 2.14, 95% CI 1.41 – 3.24).

Conclusions:
Flight attendants experience increased rates of respiratory illnesses compared to a population sample. The frequency of symptoms of nasal congestion, throat or eye irritation is associated with occupational SHS exposure in the pre-smoking ban era.

 

Second-hand tobacco smoke in never smokers is a significant risk factor for coronary artery calcification

David F. Yankelevitz, Claudia I. Henschke, Rowena Yip, Paolo Boffetta, Joseph Shemesh, Matthew D. Cham, Jagat Narula, Harvey S. Hecht

6/01/2013

publications
Abstract
Background:
An association between SHTS and CAC was recently reported in a single study, but the quantitative aspects of the relationship are not known.
Methods:
A cohort of 3,098 never smokers 40 to 80 years of age, enrolled in the FAMRI-IELCAP (Flight Attendant Medical Research Institute International Early Lung Cancer Action Program) screening program, completed a SHTS questionnaire, and had a low-dose nongated computed tomography scan. The questionnaire provided a quantitative score for total SHTS exposure, as well as separately as a child and as an adult at home and at work; 4 categories of exposure to SHTS were identified (minimal, low, moderate, and high exposure). CAC was graded using a previously validated ordinal scale score that ranged from 0 to 12. Logistic regression analysis of the prevalence and ordered logistic regression analysis of the extent of CAC were performed to assess the independent contribution of SHTS adjusted for age, sex, diabetes, hypercholesterolemia, hypertension, and renal disease. Linear and quadratic regression analyses of CAC and SHTS were performed.Results:
The prevalence of CAC was 24.3% (n �� 754) and was significantly higher in those with more than minimal SHTS exposure compared with those with minimal SHTS exposure (26.4% vs. 18.5%, p �� 0.0001). The adjusted odds ratios for CAC prevalence were 1.54 (95% confidence interval: 1.17 to 2.20) for low SHTS exposure, 1.60 (95% confidence interval: 1.21 to 2.10) for moderate exposure, and 1.93 (95% confidence interval: 1.49 to 2.51) for high exposure. The association of the extent of SHTS with the extent of CAC was confirmed by the adjusted odds ratio (p �� 0.0001).

Conclusion:
The presence and extent of CAC were associated with extent of SHTS exposure
even when adjusted for other risk factors for CAC, suggesting that SHTS exposure causes CAC. Coll Cardiol Img 2013;6:651–7) © 2013 by the American College of Cardiology Foundatio

Welcome to the FA Health Blog

The self-reported health of U.S. flight attendants compared to the general population

Eileen McNeely1*, Sara Gale1,2, Ira Tager2, Laurel Kincl3, Julie Bradley1, Brent Coull1 and Steve Hecker

3/10/2014

publications
Abstract
Background:
Few studies have examined the broad health effects of occupational exposures in flight attendants apart from disease-specific morbidity and mortality studies. We describe the health status of flight attendants and compare it to the U.S. population. In addition, we explore whether the prevalence of major health conditions in flight attendants is associated with length of exposure to the aircraft environment using job tenure as a proxy.
Methods:
We surveyed flight attendants from two domestic U.S. airlines in 2007 and compared the prevalence of their health conditions to contemporaneous cohorts in the National Health and Nutrition Survey (NHANES), 2005-2006 and 2007-2008. We weighted the prevalence of flight attendant conditions to match the age distribution in the NHANES and compared the two populations stratified by gender using the Standardized Prevalence Ratio (SPR). For leading health conditions in flight attendants, we analyzed the association between job tenure and health outcomes in logistic regression models.Results:
Compared to the NHANES population (n =5,713), flight attendants (n = 4,011) had about a 3-fold increase in the age-adjusted prevalence of chronic bronchitis despite considerably lower levels of smoking. In addition, the prevalence of cardiac disease in female flight attendants was 3.5 times greater than the general population while their prevalence of hypertension and being overweight was significantly lower. Flight attendants reported 2 to 5.7 times more sleep disorders, depression, and fatigue, than the general population. Female flight attendants reported 34% more reproductive cancers. Health conditions that increased with longer job tenure as a flight attendant were chronic bronchitis, heart disease in females, skin cancer, hearing loss, depression and anxiety, even after adjusting for age, gender, body mass index (BMI), education, and smoking.Conclusions:
This study found higher rates of specific diseases in flight attendants than the general population. Longer tenure appears to explain some of the higher disease prevalence. Conclusions are limited by the cross-sectional design and recall bias. Further study is needed to determine the source of risk and to elucidate specific exposure-disease relationships over time.

 

Miscarriage among flight attendants

Barbara Grajewski, Elizabeth A. Whelan, Christina C. Lawson, Misty J. Hein, Martha A. Waters, Jeri L. Anderson, Leslie A. MacDonald, Christopher J. Mertens, Chih-Yu Tseng, Rick T. Cassinelli II, and Lian Luo

3/26/2015

Background:
Cosmic radiation and circadian disruption are potential reproductive hazards for flight attendants.

Methods:
Flight attendants from 3 US airlines in 3 cities were interviewed for pregnancy histories and lifestyle, medical, and occupational covariates. We assessed cosmic radiation and circadian disruption from company records of 2 million individual flights. Using Cox regression models, we compared respondents (1) by levels of flight exposures and (2) to teachers from the same cities, to evaluate whether these exposures were associated with miscarriage.

Results:
Of 2654 women interviewed (2273 flight attendants and 381 teachers), 958 pregnancies among 764 women met study criteria. A hypothetical pregnant flight attendant with median firsttrimester exposures flew 130 hours in 53 flight segments, crossed 34 time zones, and flew 15 hours during her home-base sleep hours (10 pm–8 am), incurring 0.13 mGy absorbed dose (0.36 mSv effective dose) of cosmic radiation. About 2% of flight attendant pregnancies were likely exposed to a solar particle event, but doses varied widely. Analyses suggested that cosmic radiation exposure of 0.1 mGy or more may be associated with increased risk of miscarriage in weeks 9–13 (odds ratio = 1.7 [95% confidence interval = 0.95–3.2]). Risk of a first-trimester miscarriage with 15 hours or more of flying during home-base sleep hours was increased (1.5 [1.1–2.2]), as was risk with high physical job demands (2.5 [1.5–4.2]). Miscarriage risk was not increased among flight attendants compared with teachers.

Conclusions:
Miscarriage was associated with flight attendant work during sleep hours and high physical job demands and may be associated with cosmic radiation exposure.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4849674/pdf/pone.0154432.pdf

 

Clear Skies and Grey Areas: Flight Attendants’ Secondhand Smoke Exposure and Attitudes toward Smoke-Free Policy 25 Years since Smoking was Banned on Airplanes

Frances A. Stillman, Andrea Soong , Laura Y. Zheng, and Ana Navas-Acien

06/04/15

publications
Abstract
Our objective was to provide descriptive data on flight attendant secondhand smoke (SHS) exposure in the work environment, and to examine attitudes toward SHS exposure, personal health, and smoke-free policy in the workplace and public places. Flight attendants completed a web-based survey of self-reported SHS exposure and air quality in the work environment. We assessed the frequency and duration of SHS exposure in distinct areas of the workplace, attitudes toward SHS exposure and its health effects, and attitudes toward smoke-free policy in the workplace as well as general public places. A total of 723 flight attendants participated in the survey, and 591 responded to all survey questions. The mean level of exposure per flight attendant over the past month was 249 min. The majority of participants reported being exposed to SHS always/often in outdoor areas of an airport (57.7%). Participants who worked before the in-flight smoking ban (n=240) were more likely to support further smoking policies in airports compared to participants who were employed after the ban (n=346) (76.7% versus 60.4%, p-value<0.01). Flight attendants are still being exposed to SHS in the workplace, sometimes at concerning levels during the non-flight portions of their travel. Flight attendants favor smoke-free policies and want to see further restrictions in airports and public places.