What you need to know

Potential cabin air hazards may include:

• Ventilation hazards, including carbon monoxide, ozone, and carbon dioxide levels
• Pesticide exposures on certain flights
• Transmission of communicable diseases from sick passengers
• Cabin altitude and pressurization changes
• Air contamination events, when cabin air becomes contaminated with breakdown products from heated engine oil or hydraulic fluid

Here you can learn more about cabin air quality and how you can lower your exposure to potential cabin air hazards.

What is not known

We don’t know what causes most health problems that could be linked to cabin air. If you are exposed to a potential cabin air hazard and have health problems, it may not be possible to tell if it was caused by your work conditions or if it was caused by something else.

We don’t know what levels of potential hazards in cabin air are safe for every person.

What you can do to reduce exposure to hazards in cabin air

Be aware of your company’s procedures for dealing with these exposures. Here are some ways to reduce your exposure:

• Reduce exposure to communicable diseases by washing or sanitizing your hands often. Wash after serving food or beverages to passengers, helping them with their baggage, and before eating. Learn more about how to reduce exposure to communicable diseases on aircraft.
• Pesticides are sometimes used on the inside of airplanes on certain flights. Learn more about pesticide exposure.
• Follow up with your doctor if you have concerns about these exposures. Make sure your doctor knows that you work as a crewmember. Sharing this and other information with your doctor may be useful. You or your doctor may also contact us for more information.

What you need to know

Aircrew may be more likely to get skin cancer and female flight attendants may be more likely to get breast cancer than the general population. Here you can learn more about steps you can take to reduce your risk.

What is known about the risk of cancer in aircrew?

Aircrew are exposed to elevated levels of cosmic ionizing radiation and circadian rhythm disruption from traveling across time zones and working when others would normally be asleep. Ionizing radiation is known to cause cancer. Some studies suggest that circadian rhythm disruption may also cause cancer.

Based on aircrew research, crew members may be more at risk for:

• Skin cancer: A number of studies have been done to look at the risk of cancer among aircrew. Overall, they indicate that crewmembers are more likely to be diagnosed with melanoma and other skin cancers.
• Breast cancer: Studies also suggest that female flight attendants are more likely to be diagnosed with breast cancer than the general population.
• Kaposi sarcoma and non-Hodgkin lymphoma: Studies have found that male flight attendants have an increased risk of Kaposi sarcoma and non-Hodgkin lymphoma. HIV infection is a risk factor for both Kaposi sarcoma and non-Hodgkin lymphoma, and the increased risk of these cancers among male flight attendants is most likely related to HIV/AIDS.

Because smoking used to be allowed on planes years ago, there is concern about health effects among crew members who were exposed to second hand smoke. However, studies to-date have not found an increase in lung cancer among aircrew.

What is not known?

We don’t know for sure why aircrew are more likely to be diagnosed with melanoma and other skin cancers than the general population.

UV radiation from sun exposure is a major risk factor for malignant melanoma and other skin cancers. It’s possible that crewmembers are exposed to the sun more outside of work than the general population. They may also be exposed to the sun more during flights.

We know the level of UV radiation is higher at commercial aircraft altitudes than it is at sea level, but we don’t know how much UV radiation is blocked by the windshield and cabin windows on all commercial aircraft. Research suggests that plastic windshields block most UVA and UVB radiation from the sun. Research suggests that glass windshields block most UVB radiation but block slightly less than half of UVA radiation from the sun.

We don’t know for sure why female flight attendants are more likely to be diagnosed with breast cancer than the general population, but it may be because of

• Exposure to elevated levels of cosmic ionizing radiation
• Circadian rhythm disruption from traveling across time zones and working when others would normally be asleep
• Differences in non-work related risk factors for breast cancer

Why might aircrew be concerned about cancer?

Although we don’t know why, aircrew seem to be more likely to get skin cancer and breast cancer.

• Skin cancer is the most common cancer in the United States. Melanoma is the deadliest kind of skin cancer.
• Breast cancer is the most common cancer among American women other than skin cancer. About one in eight women will develop breast cancer at some point during their lifetime.

What aircrew can do to reduce risk of breast cancer

If you are concerned that exposure to cosmic ionizing radiation and circadian rhythm disruption at work may increase your risk of breast cancer, you can try to reduce your exposure to cosmic ionizing radiation and circadian rhythm disruption.

What aircrew can do to reduce risk of skin cancer

To reduce your risk of skin cancer, protect your skin from the sun and avoid indoor tanning. You can take the following general steps to protect your skin from the sun:

• Use sunscreen at work since some UV radiation comes through the windows on some aircraft, especially aircraft with glass windows.
• Learn more about sun safety.

What you need to know

Aircrew and passengers are exposed to cosmic ionizing radiation on every flight. Here you can learn more about cosmic ionizing radiation, how you can be exposed, exposure levels, and possible health effects.

What is cosmic ionizing radiation?

Cosmic ionizing radiation (or cosmic radiation) is 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 crewmembers are exposed to higher levels of cosmic radiation.

Cosmic radiation exposures on aircraft include:

• galactic cosmic radiation, which is always present
• solar particle events, sometimes called “solar flares”

Are there any known health effects from cosmic ionizing radiation?

• The World Health Organization (WHO) International Agency for Research on Cancer (IARC) says that ionizing radiation causes cancer in humans. Ionizing radiation is also known to cause reproductive problems. We are looking more specifically at whether cosmic ionizing radiation is linked to cancer and reproductive problems.
• Most studies of radiation health effects have looked at groups with much higher radiation doses from different kinds of radiation (atomic bomb survivors; patients who received radiation therapy).

What is not known

We don’t know what causes most health problems that could be linked to radiation, including some forms of cancer and reproductive health issues like miscarriage and birth defects. If you are exposed to cosmic ionizing radiation and have these health problems, we can’t tell if it was caused by your work conditions or something else.

• We don’t know what levels of cosmic radiation are safe for every person.

How much cosmic radiation are crew members exposed to?

The National Council on Radiation Protection and Measurements reported that aircrew have the largest average annual effective dose (3.07 mSv) of all US radiation-exposed workers.  Other estimates of annual aircrew cosmic radiation exposure range from 0.2 to 5 mSv per year.

What do guidelines or regulations say about cosmic radiation exposure levels in aircrew?

There are no official dose limits for aircrew in the United States, but there are national and international guidelines.

• The International Commission on Radiological Protection (ICRP) considers aircrew to be exposed to cosmic radiation on their jobs. They recommend effective dose limits of 20 mSv /year averaged over 5 years (that is, a total of 100 mSv in 5 years) for radiation workers and 1 mSv/year for the public. For pregnant radiation workers, the ICRP recommends a dose limit of 1 mSv throughout pregnancy. The National Council on Radiation Protection and Measurements has a 0.5 mSv recommended monthly radiation limit during pregnancy.
• European Union member states require assessment of aircrew exposure when it is likely to be more than 1 mSv /year, and adjustment of work schedules so that no individual exceeds 6 mSv/year.
• We are finding that some crewmembers may have exposure to cosmic radiation that is higher than what is recommended, and thus may be at greater risk for possible health effects.

What can crew members do to reduce exposure to cosmic radiation?

Bidding for a flight schedule to reduce cosmic radiation exposures is complicated, because reducing one exposure may increase another. Seniority, lifestyle, and personal issues also affect the ability to make these choices. Here are some actions you can consider:

• Try to reduce your time working on very long flights, flights at high latitudes, or flights which fly over the poles. These are flight conditions or locations that tend to increase the amount of cosmic radiation the crewmembers are exposed to. You can calculate your usual cosmic radiation exposures. The FAA’s CARI program website allows you to enter information to estimate your effective dose from galactic cosmic radiation (not solar particle events) for a flight.
• If you are pregnant or planning a pregnancy, it is important to consider your work exposures, including cosmic radiation. If you are pregnant and aware of an ongoing solar particle event when you are scheduled to fly you may want to consider trip-trading or other rescheduling actions if possible.
  • For flight attendants, a NIOSH study found that exposure to 0.36 mSv or more of cosmic radiation in the first trimester may be linked to increased risk of miscarriage.
  • Also, although flying through a solar particle event doesn’t happen often, a NIOSH and NASA study found that a pregnant flight attendant who flies through a solar particle event can receive more radiation than is recommended during pregnancy by national and international agencies.
• Regarding solar particle events:
  • NIOSH has estimated that pilots fly through about 6 solar particle events in an average 28-year career.
  • Avoiding exposure to solar particle events is difficult because they often happen with little warning. You can find out whether a solar particle event is currently active through these sources:
    • The National Aeronautics and Space Administration (NASA) Nowcast of Atmospheric Ionizing Radiation System (NAIRAS) is being developed to report potentially harmful flight radiation levels to flight crews and passengers.
      • NAIRAS: current radiation dose rate forecast.
    • The National Oceanic and Atmospheric Administration (NOAA) Space Weather Prediction Center’s Aviation Community Dashboard includes a forecast for solar particle events.

What Aircrew and Aircrew Employers need to know

Communicable diseases are illnesses that spread from one person to another or from an animal to a person, or from a surface or a food. Diseases can be transmitted during air travel through:

• direct contact with a sick person
• respiratory droplet spread from a sick person sneezing or coughing
• contact with blood or other body fluids
• breathing in viruses or bacteria in the air
• contact with a contaminated surface or object
• bites from insects or animals that can transmit the disease
• ingestion of contaminated food or water

Aircrew may be exposed to communicable diseases from sick travelers and co-workers. This page provides information on:

•  Some communicable diseases that may be spread among crewmembers and to crewmembers from passengers
•  What to do when there is a sick passenger or crew on the plane
•  Ways to keep aircrew healthy.

Why might aircrew be concerned about communicable diseases?

Communicable diseases may be spread to crewmembers or to passengers during air travel due to close proximity. Crew members may be exposed to communicable diseases during flights with air travelers and layovers in airports.

What can be done to manage sick passengers and crew?

CDC has developed guidance for airlines for managing ill passengers/crew. and reporting deaths and certain illnesses to CDC. Specific guidance is available for several diseases. Some of these diseases are rare, but of concern because they can be serious.

When specific recommendations aren’t available, aircrew should follow the routine infection control guidance for cabin crew and consult with their employer’s occupational health program to protect themselves and others from communicable diseases while they are working.

What you need to know

Circadian rhythm is the internal biological clock that regulates body functions based on our wake/sleep cycle. It can be disrupted by changes in sleep pattern. Aircrew members may experience circadian rhythm disruption (specifically “jet lag”) as they work. Here you can learn more about circadian rhythm disruption, why it occurs, possible health effects, and how crewmembers can reduce the effects of circadian disruption.

Why might aircrew be concerned about circadian rhythm disruption?

Aircrew often travel across time zones and work when others would normally be asleep. This can affect their internal biological clock and disrupt normal sleep patterns which can lead to fatigue, difficulty sleeping, changes in mood, injuries, stomach and intestinal symptoms, and other health problems.

Although travelers who get circadian disruption after a single flight recover after 1-2 weeks, many crewmembers are continually exposed and show evidence of chronic circadian rhythm disruption. Some crewmembers may have higher exposure to circadian disruption than most of their coworkers and thus may be at greater risk for possible health effects.

A study we completed found that travel across time zones and work during a flight attendant’s normal sleep hours were both linked to chronic circadian disruption in a group of flight attendants. The same group of flight attendants slept longer than a comparison group of teachers, but their sleep was much more disturbed.

• Working during normal sleep hours 15 hours or more during the first trimester of pregnancy was linked to increased risk of miscarriage in a NIOSH study of flight attendants.
• Disrupting your biological clock and sleep cycle can cause much more than problems with sleeping. It can also change normal conditions and processes in the body, including hormone levels.
• The World Health Organization says that shift work (including the kind of circadian disruption that aircrew encounter) probably causes cancer.

What is not known

• We don’t know what causes most health problems that may be linked to circadian disruption, including some types of cancer as well as reproductive health issues like miscarriage and birth defects. If you experience circadian disruption and have these health problems, we can’t tell if the problem was caused by your work conditions or if it was caused by something else.
• We don’t know how much circadian disruption is safe for every person.

What can be done to reduce or eliminate exposure?

Bidding for a flight schedule to reduce circadian disruption exposures is complicated, because reducing one exposure may increase another. Seniority, lifestyle, and personal issues also affect the ability to make these choices. Here are some actions you can consider:

• If possible, try to reduce your time working on very long flights, flights that cross many time zones, or flights scheduled for when you are normally asleep at home. These are flight conditions that tend to increase the amount of circadian disruption the aircrew is exposed to.
• If you are pregnant or planning a pregnancy, it is important to consider your work exposures, including circadian disruption. Learn more about how your job could impact your reproductive health.

• Adopt good sleep habits. The National Institutes of Health (NIH) and The National Sleep Foundation suggest ways to reduce the effects of circadian disruption, including:
  • As your work schedule permits, keep the same times for going to sleep and waking up that you use in your home time zone. It is best not to change your sleep schedule on days off; try to get up at about the same time. If you need to catch up on sleep, go to bed earlier.
  • Use ear plugs and eye masks to reduce noise and light when you sleep.
  • Sleep in a cool room with comfortable mattress and pillows.
    • If you are sleeping away from home, set up a quiet, very dark, comfortable, and cool hotel bedroom. Block any light coming into the bedroom under the doorways or through the windows. Cover lighted clock dials. Remember to pack an eye mask, ear plugs and clothes pins (to pin the drapes together).
  • Avoid alcohol 2-3 hours before bedtime; it will disturb sleep if taken at this time.
  • Caffeine can affect your body for five hours or more. Limiting your caffeine intake may help improve sleep.
  • Avoid heavy or spicy meals 2–3 hours before bed.
  • About 1.5 hours before bedtime, avoid using backlit electronic screens of computers, tablets, cell phones, and televisions.

What you need to know

When job stress is high due to heavy demands and pressures or in response to a traumatic event, your body and mind can experience the “flight or fight” response. Your job performance and health may decline if your job stress is very high or lasts a long time. Here crewmembers can learn more about how to recognize and manage job stress.

What are job stressors?

Workplace conditions or events that cause job stress are called job stressors. Aircrew may face job stress from:

• occasional or repeated heavy job demands
• working long and irregular hours
• sleep disruption
• job insecurity
• encounters with uncooperative or unpleasant passengers or co-workers/managers
• unpredictable schedule disruptions
• extended time away from home and loved ones
• traumatic events, such as in-flight emergencies or disasters

What types of job stress are there?

Acute stress

Acute stress can occur when job demands, pressures, or uncertainties are higher over a relatively short period of time. This is generally followed by a return to low or more moderate levels. Examples might include working back-to-back flight segments with full passenger loads, flying during bad weather, or if a passenger medical event occurs in-flight. The symptoms of acute stress are generally mild to moderate and temporary. They can include:

• physical and/or emotional tension
• digestive or sleep disturbances
• fear and anxiety
• irritability
• needing time to unwind after work before interacting with family and friends
• sleep disturbance

Chronic stress

Chronic or prolonged stress can develop from experiencing heavy demands and pressures over an extended period of time. There is also little or no control over those demands, limited resources to meet those demands, and/or limited relief or “down-time.” Symptoms of chronic stress can range from mild to high and are generally persistent. Those with chronic stress may experience the symptoms associated with acute stress listed above, as well as:

• difficulty making decisions
• loss of interest in normal activities
• sleep problems
• feeling powerless
• difficulty with relationships
• feeling sad and having other symptoms of depression

Traumatic incident stress

Aircrew are responsible for the safety of passengers and must respond quickly to medical, mechanical or other in-flight emergencies. Such emergencies can be considered traumatic incidents if they involve damage to physical structures or spaces, bodily injury, or death. Traumatic incident stress may occur at the time of the event or weeks or months later. It may include severe acute physical symptoms such as difficulty breathing, symptoms of shock, or chest pain that requires immediate medical attention. Visit the NIOSH traumatic incident stress topic page to learn more signs and symptoms.

What can be done to reduce or eliminate job stress?

What employees can do

Times of stress can be overwhelming, and may lead to pleasure-seeking in the form of unhealthy choices that may worsen the effects of stress. You can be proactive by taking steps to reduce the effects of job stress by finding support and making healthy choices. Evidence shows that supportive relationships can reduce stress levels, along with taking better care of yourself. Here are some things you can do:

• Find support. Seek help from a trusted partner, family member, friend, counselor, doctor, or clergyperson. Consider using programs offered by your employer if available.
• Connect socially with others.
• Talk with your supervisor, a union steward, or a trusted senior member of your organization about work conditions that may be causing or aggravating your stress.  When discussing issues it may help to seek clarification about roles and priorities, available resources, and options for doing things differently that may not be apparent.
• Start or resume routines that are comforting or soothing to you especially if you’ve been stressed or your schedule has been disrupted. For example, practice yoga or find other activities that may help you relax, such as taking a warm bath.
• Make time to do things that make you happy – even if for brief periods of time.
• Limit time spent watching television, in front of computer screens or other electronic devices.
• Choose healthier meal options and pack healthy snacks.
• Go for walks or exercise regularly.
• Get enough sleep.
• Avoid drugs and alcohol.

What managers can do

Just as it is necessary to design jobs in a way that protects workers from toxic chemicals, jobs should also be designed to reduce worker exposure to job stressors. While some stressors such as shiftwork, long work hours, or schedule delays due to weather or mechanical issues cannot be eliminated, airline management should make extra efforts to identify, evaluate and implement work schedule practices that aid crewmember recovery following long flights. Additionally, programs should be developed to provide employees exposed to work-related traumatic incidents with mental health debriefings and to direct them to needed resources. Here is what managers can do to help reduce their crewmembers’ job stress:

• Set fair and reasonable expectations.
• Clearly define workers’ roles and responsibilities.
• Recognize and reward employee contributions.
• Permit employees to have a say and participate in decisions affecting their jobs
• Give workers opportunities to participate in decisions and actions affecting their jobs.
• Improve communication–reduce uncertainty about career development and future employment.
• Balance workload by ensuring adequate resources (staff, time) to accommodate flight demands.
• Design jobs to provide meaning, stimulation, and opportunities for applying skills.
• Permit work schedule flexibility to enable crewmembers to better balance job demands and responsibilities with those outside the job, including childcare.
• Establish and maintain an effective and proactive workforce protection program that is automatically activated for personnel involved in work-related traumatic incidents.

What you need to know

Aircrew may be at risk for musculoskeletal disorders. Work-related strains and sprains of muscles, tendons, and supporting tissues can happen from lifting, bending, carrying, reaching, working in confined spaces, and using repetitive motions. Turbulence or sudden airplane movements can cause imbalance, increasing risk of injury associated with a fall. Here you can learn more about what you can do to reduce your risk of developing these kinds of job-related injuries.

What are musculoskeletal disorders?

Musculoskeletal disorders are short or long-term injuries to the nerves, tendons, muscles and the supporting structures of the body, such as bones and ligaments.

A musculoskeletal disorder is considered work-related if the injury is caused or aggravated by work tasks such as:

• lifting,
• pushing,
• pulling,
• reaching,
• prolonged standing,
• awkward postures including twisting,
• constrained postures,
• performing repetitive motions

Symptoms of musculoskeletal disorders can include:

• pain
• stiffness
• swelling
• numbness
• tingling

What you can do to reduce or eliminate exposure

When possible, avoid or limit:

• Awkward body postures (bent or twisted back, arms overhead or far in front of the body)
• Repetitive movements
• Heavy or overhead lifting
• Forceful pushing or pulling
• Ask your employer to fix a cart if the wheels do not operate properly

If you are pregnant:

• Reduce heavy/bulky lifting in accordance with the NIOSH provisional guidelines.
• Reduce or eliminate
  • Stooping, bending, or twisting at the waist
  • Lifting overhead
  • Lifting from below mid-shin

What you need to know

Occupational hearing loss is one of the most common work-related injuries in the United States. There are many sources of noise during flight operations. Here you can learn more about how aircrew can lower exposure to aircraft noise.

What are sources of aircraft noise?

• On the ground, aircraft engines, takeoff preparations, and braking are sources of noise on aircraft.
• When airborne, the aircraft engines and high speed turbulence over the fuselage are the largest sources of noise on aircraft. Announcements and mechanical noises from food and beverage service are other sources of noise.
• NIOSH conducted noise surveys in 2002 and 2003 on regional jets and turboprop aircraft.  Noise levels were generally lower than NIOSH and/or OSHA recommended or regulated exposure levels, but some measurements briefly approached or surpassed these levels.  Hearing protection, especially during takeoff and landing, is one option for reducing these exposures.
• A study of noise on Airbus A321 aircraft reported levels of 60-65 decibels (dBA) before takeoff; 80-85 dBA during flight; and 75-80 dBA during landing. The outside of aircraft engines (around 140 dB at takeoff) and conditions on other aircraft may have higher or lower noise levels. Sound insulation also varies among aircraft.

What are the recommended levels for noise at work?

• We recommend that all worker exposures to noise be controlled below a level equivalent to 85 dBA for eight hours to minimize occupational noise induced hearing loss.
• We also recommend a 3 dBA exchange rate so that every increase by 3 dBA doubles the amount of the noise and halves the recommended amount of exposure time.

What is not known

• Hearing loss accumulates over a lifetime. If you are exposed to aircraft noise and have health problems, we can’t tell if it was caused by your work conditions or if it was caused by something else.
• Although we know general ranges of noise levels on aircraft, noise levels have not been measured on all aircraft and can vary.

What you can do to reduce exposure to noise on aircraft

• Wear hearing protection during take-off and landing.
• The Airbus A321 study suggests that noise levels are higher in the rear of the cabin, near and behind the engines and propellers, and near windows. When you have a choice, moving to other locations in the cabin may reduce your noise levels.
• Follow up with your doctor if you have concerns about your noise exposures. Make sure your doctor knows that you work as a crewmember. Sharing this and other information with your doctor may be useful. You or your doctor may also contact us for more information.

What is disinsection?

Some countries require that in-bound flights be treated with pesticides to prevent the spread of insects, or diseases carried by insects, like malaria or Zika. The process of applying pesticides to kill insects is called disinsection.

Disinsection methods can include spraying the aircraft cabin with an insecticide (either before or after passengers board, or while in flight) or treating the aircraft’s inside surfaces (while passengers are not on board) with an insecticide that can be effective at killing insects for up to 8 weeks.

What can air crew do to reduce or eliminate exposure to pesticides?

• Talk with your employer or employee representative about concerns you have with pesticide exposure.
• Avoid skin contact with surfaces that are still wet with pesticide.
• Follow up with your supervisor and healthcare provider if you have concerns about your potential pesticide exposure. Make sure your doctor knows that you work as a crewmember.

What air and ground crew should know

• Aircrew and passengers can be exposed to pesticides during aircraft disinsection or from contact with treated surfaces within the aircraft (fuselage).
• Aircrew, passengers, and ground crew can unknowingly be exposed to insecticides even when they are on flights that don’t require disinsection (including flights within the continental United States) because aircraft that have been treated with insecticides can be used on multiple flight routes.
• Aircrew may spray a pesticide in the aircraft cabin after the aircraft leaves the gate and/or before it lands.
• Ground crew (including maintenance or cleaning staff) may treat surfaces inside the aircraft with a pesticide prior to air crew and passengers boarding. Additionally, ground crew might enter an aircraft shortly after disinsection and before treated surfaces have dried.

Pesticide exposure may occur when eating or drinking products that have come in contact with surfaces treated with pesticides.

How is disinsection regulated?

• Aircraft disinsection is allowed under international law, but not all countries require it. The U.S. Environmental Protection Agency (EPA) has not currently approved any pesticides for use in passenger cabins on commercial aircraft.The U.S. Department of Transportation provides information on which countries require disinsection on inbound flights.
• The only pesticides recommended by the World Health Organization (WHO) for aircraft disinsection are synthetic pyrethroids (permethrin, d-phenothrin, and 1R-trans-phenothrin). Other pesticides, including DDT (dichlorodiphyltrichloroethane), were used to disinsect aircraft several years ago but are no longer used.

There is no single set of standards for how aircraft disinsection is performed. It is unknown whether all aircraft disinsection adheres to the WHO guidelines regarding disinsection, label directions, and good occupational hygiene practices. Pesticides should always be used according to their label directions and following good hygiene practices.

What we don’t know

• It is unknown whether long-term exposure to the chemicals used in aircraft disinsection might cause health effects in air and ground crew.
• Pesticides used for aircraft disinsection are mixtures including solvents, propellants, surfactants, and synergists. Research on the health effects of exposure to these mixtures, as well as possible combined effects with other chemicals present in aircraft environments, are needed.
• Although pyrethroid pesticides are generally not believed to cause allergy or asthma symptoms, allergic sensitization, asthma symptoms, and anaphylaxis (a sudden and severe allergic reaction) have been reported related to exposure to commercial aircraft disinsection products.Additional research is needed to clarify the relationship between disinsection and asthma/allergy.
• Reports from passengers and air crew suggest that there are major differences in how disinsection is performed. Better understanding of current practices is needed.
• Further studies of aircraft surfaces and air crew are needed to evaluate whether repeated applications of insecticides in a cabin, or improper application of pesticides in aircraft, might cause increased exposure.
• Some insects are resistant to the pesticides used in aircraft disinsection. Research to evaluate the usefulness of chemical disinsection, as well as non-chemical and engineering controls that can be used as an alternative, is needed.

What you need to know

Working as a flight attendant or pilot may affect your reproductive health because of some of the hazards of the job, such as:

• Cosmic ionizing radiation
• Circadian rhythm disruption (jet lag) or shift work
  • Working when you would normally be asleep
  • Long working hours
  • Working across time zones
• Physical job demands, such as:
  • Standing for long periods of time
  • Heavy lifting
  • Bending from the waist

Here you can learn more about possible reproductive health concerns from working as a crew member and ways to stay healthy.

Why might aircrew be concerned about reproductive health and in-flight exposures?

• Exposure to ionizing radiation at work could increase your chances of having reproductive health problems. For flight attendants, a NIOSH study found that exposure to 0.1 mGy (0.36 mSv) or more of cosmic radiation in the first trimester may be linked to increased risk of miscarriage.
• NIOSH and NASA have found that a pregnant flight attendant who flies through a solar particle event can receive more radiation than is recommended during pregnancy by national and international agencies
  • Cosmic radiation exposures on aircraft include both galactic cosmic radiation, which is always present, and solar particle events, or “solar flares”. Solar particle events are transient, unpredictable solar surface eruptions of radiation.
  • Exposure to a solar particle event doesn’t happen often. We estimated that pilots fly through a solar particle event about 6 times over an average 28-year career.
• Working during your normal sleep hours can change your circadian rhythms, which regulate your menstrual cycle and your pregnancy hormones. For flight attendants, working during normal sleep hours 15 hours or more during the first trimester of pregnancy has been linked to increased risk of miscarriage in our study.
• Heavy lifting, standing for long periods of time, or bending a lot during pregnancy could increase your chances of having menstrual disorders, miscarriage, or preterm birth, or injury during pregnancy. For flight attendants, our study found that high physical job demands (standing and walking more than 8 hours a day or bending at the waist more than 25 times a day) was linked to increased risk of miscarriage.

What is not known?

• We don’t know what causes most reproductive problems. If you are exposed to cosmic ionizing radiation, shift work, long working hours, or physical job demands and have a miscarriage or other reproductive problems, we can’t tell if it was caused by your work conditions or if it was caused by something else.
• We don’t know what levels of these exposures are safe for every person, or how to achieve safe exposure levels for all pregnant crewmembers.

What can be done to improve reproductive health among crew members?

• Pregnant crewmembers should try to reduce physical job demands including standing for long periods of time, heavy lifting, and bending from the waist.
• Bidding for a flight schedule to reduce circadian disruption exposures is complicated, because reducing one exposure may increase another. Seniority, lifestyle, and personal issues also affect the ability to make these choices. In general:
  • Try to reduce your time working on flights when you are normally asleep at home. One way you may be able to do this is to work shorter flights near where you live.
  • To reduce cosmic radiation exposure, try to reduce your time working on long flights, flights at high latitudes, or flights which fly over the poles.
  • As much as you can when you fly, be aware of space weather and solar particle events by using information from NASA and NOAA prediction systems.

What you need to know

Some studies suggest that aircrew may be more likely than other workers to have respiratory symptoms and diseases. Many crewmembers were exposed to secondhand smoke when smoking was allowed on aircraft, and this may have increased their risk. Some communicable diseases and other exposures in the aircraft may also play a role. Here you can learn about steps you can take to reduce your risk.

What is known about respiratory symptoms and diseases in aircrew?

• Some studies suggest that respiratory symptoms and diseases including irritated, stuffy or runny nose, dry throat, chest illness, cold or flu, wheezing, and chronic bronchitis are more common in flight attendants than other workers.
• There is less information about respiratory symptoms and diseases among cockpit crew, but some data suggest they may be more likely to have respiratory symptoms as well.
• Many crewmembers were exposed to secondhand smoke when smoking was allowed on aircraft. They can still be exposed to secondhand smoke in some airports, where smoking is still allowed. You can be exposed to secondhand smoke if you spend time in or pass by areas where smoking is allowed.
• Working in an area where you breathe secondhand smoke can increase your chances of lung cancer, coronary heart disease, and stroke.
• Breathing secondhand smoke during pregnancy can increase your chances of having a baby with a low birthweight.
• Communicable diseases that cause respiratory symptoms may be transmitted during air travel.
• Other exposures on aircraft can cause respiratory symptoms including pesticides.

What is not known?

Secondhand smoke in aircraft may cause asthma, worsening of asthma control, respiratory symptoms, COPD (chronic obstructive pulmonary disease) and decline in lung function in adults.

Exposure to secondhand smoke during pregnancy may cause preterm delivery.