How to deal with air pollution during travel
Air pollution is a toxic soup of chemicals, particulate matter, and biological materials that react with each other and can reach harmful concentrations both indoors and outdoors. Air pollution is a major public health issue that contributes to chronic diseases, increased hospitalization, and premature mortality. In fact, the World Health Organization estimates that outdoor air pollution causes
3.7 million premature deaths worldwide every year.
What are the symptoms of air pollution exposure?
The short-term symptoms of exposure to air pollution include itchy eyes, nose and throat, wheezing, coughing, shortness of breath, chest pain, headaches, nausea, and upper respiratory infections such as bronchitis and pneumonia. It also exacerbates asthma and emphysema.
Long-term effects include lung cancer, cardiovascular disease, cerebrovascular disease, chronic respiratory illness, and developing allergies. Air pollution is also associated with heart attacks and strokes.
Some of the culprits causing air pollution include:
- Carbon monoxide (CO): Reduces oxygen from reaching organs and tissues. Exposure to high levels also affects mental alertness and vision.
- Ozone (O3): Is not the protective layer in the Earth’s upper atmosphere, but the ‘bad’ one near ground level that forms as a result of toxic chemicals reacting with sunlight. This type of ozone irritates the respiratory system and can inflame and damage the lungs’ lining. Long-term exposure results in diminished pulmonary function due to scarred tissue and an increase in respiratory infections.
- Sulfur dioxide (SO2): Constricts your airways and in the long-term can diminish the lungs’ defence mechanisms.
- Nitrogen oxide (NO2): Causes inflammation of the respiratory system, reduces immunity to respiratory infections, and aggravates asthma and bronchitis.
These pollutants and others can form small solid or liquid particles referred to as Particulate Matter (PM). PM causes significant damage, especially to people suffering from chronic heart and lung disease. Depending on the size of the inhaled particles, they deposit in the lungs and cardiovascular system and migrate to other organs, including the brain.
Planning your trip
We often hear about large cities having the worst air pollution records as a result of vehicle emissions; Hong Kong, Delhi, Manila, Cairo, Mexico City, and Santiago come to mind. However, smog also affects rural areas. Weather patterns, geographic landscape, and whether polluting industries such as smelting, refineries, mining, and heavy manufacturing are all contributing factors to air pollution regardless if you are in an urban or rural area.
No matter your destination, you will not be able to fully escape air pollution. However, the length of exposure and concentration of pollutants will have an impact on your health during travel.
When planning your trip, consider these five factors to help you mitigate the effects of air pollution.
- Health Status: What is your current health status? Do you have asthma, allergies, chronic bronchitis, heart or lung disease?
- Age: Are you an older person or travelling with young children? Older individuals are more susceptible to air pollution due to pre-existing conditions. Newborns and children are also more susceptible, as they take in more air (higher level of pollutants) for their body weight than adults.
- Destination: Are you going to an urban area, a city in a valley, or where rain is uncommon? In urban areas, air pollution levels can be high due to increased vehicle emissions. Cities in valleys are also prone to high air pollution levels because the air becomes trapped, making it less likely for pollutants to be blown away. Dry areas with minimal rain can also experience persistent bad air quality because pollutants are not washed away.
- Length of trip: Are you going for a short or long-term trip? Studies on the health impacts of low air quality are typically done on residents with long-term exposure. As a result, we do not know the full extent of the air pollution risks on travellers. However, available data indicates that short-term exposure to air pollution can still have health effects – in a small study conducted on young, healthy travellers taking short term trips to highly polluted cities, researchers found that lung function decreased from 6-20%. Lung function recovered once travellers returned home.
- Season: What time of year are you going? Depending on seasonal weather patterns, smog can occur during hot and humid days. Smog can also occur in the winter due to increased use of heating systems. Depending on your destination, seasonal weather events such as forest/bush fires, dust storms, and monsoons may affect air pollution levels. If you suffer from asthma or allergies, also consider the occurrence of pollen season at your destination.
Quick tips for travellers
To protect yourself from the short-term effects of air pollution, consider the following tips:
- While it may not be convenient, heed warnings to stay indoors during high smog alert days. Ask around and observe what locals are doing. Before you leave for your trip, find out where you can access local air quality alerts.
- Avoid strenuous or extreme physical activity. If exercise must be done outdoors, do it in the early morning to reduce your exposure to air pollution. Even if you are very fit, low air quality can impact your health and may have long-term consequences. Seek immediate medical attention if you have trouble breathing or chest pain.
- If you have asthma: Minimize exposure and travel with an inhaler or an oral steroid (consult your doctor to see what is best for you).
- If you suffer from Chronic Obstructive Pulmonary Disease (COPD), including chronic bronchitis and emphysema: In addition to your usual medications, carry an inhaler, antibiotic, and oral steroid (consult your doctor to see what is best for you).
- If you have a history of cardiac or pulmonary disease: Ensure that your condition is under control before departure. You may want to reduce the duration of your stay in an area with high air pollution.
- If you wear contact lenses: Beware of eye irritation that may arise in areas with heavy dust and ozone. If you experience irritation, wash eyes gently with clean water to cool them, use lubricating eye drops, or opt for glasses on heavily polluted days.
- For older travellers, get a physical exam that includes a stress and lung capacity test prior to departure.
- If you are travelling with newborns or young children, minimize exposure or consider not travelling to areas with low air quality.
- Depending on your destination, find out from your doctor if a breathing mask is a good option for you. If you decide to wear a mask, N95 or N99 masks are preferable and must be custom fitted to your face. It’s important to ensure the mask fits your face well to prevent pollutants from leaking into the sides of the mask. Masks with head straps are more secure than those with elasticated ear loops.
How to find out about air quality at your destination?
Countries and regional blocs (i.e. European Union) have different measurement standards and indexes to communicate air pollution levels. Generally however, indexes show scales from good to hazardous air quality along with advice for sensitive population groups.
The World Health Organization’s air quality guidelines recommend that the annual mean concentrations of PM2.5 should not exceed 10 µg/m3 and 20 µg/m3 for PM10. PM levels above these two measurements are considered unsafe.
To see air quality details for your destination, check out
Country Health Advice.
For real-time air quality data, visit
The World Air Quality Project.
Information last updated: April 16, 2020