If you revisited almost any major city in the northern hemisphere during the recent northern winter you’ll have noticed some changes.
Sure, the traffic was almost certainly heavier and more towering buildings will have filled the ever-changing skyline.
But, perhaps the most obvious change may have been to the quality of the air. Globally, our air is becoming more polluted – and more deadly.
More than 7 million people died from air pollution in 2012 – double previous estimates, a disturbing new report by the World Health Organization has revealed. To put the figure into perspective, that’s 13 fatalities every minute.
Among the cities with consistently high levels of air pollution, Beijing and New Delhi are among the worst. Others often included in the smoggy Top 10 are Santiago, Mexico City, Ulaanbaatar, Cairo, Kabul, and the Chinese cities of Chongqing, Guangzhou, and Hong Kong.
However, the WHO says the highest mortality rates linked to air pollution are found in low- and middle-income countries in South-East Asia and the Western Pacific – the most popular destinations with Australian travellers.
For most healthy adults, the effects of smog and haze are eye-wateringly unpleasant, but mercifully brief. Expect eye and nasal irritation, or a cough: At worst, you might experience a headache or even nausea.
Some travellers more vulnerable
However, air pollution can have more severe and long-term effects on young children, the elderly, and anyone with a chronic heart disease or lung condition, such as asthma or emphysema, according to Dr Eddy Bajrovic, Medical Director of Travelvax Australia.
“These new WHO figures are of particular concern for certain travellers,” Dr Bajrovic said this week.
“Those most at risk are the very young and the elderly, as well as anyone with an underlying chronic medical condition, particularly a chronic respiratory or cardiovascular disease.
“These people are much more likely to become sick from breathing in smog. Anyone in a high-risk category should discuss what impact air pollution could have on their health with a doctor experienced in travel medicine, their GP or medical specialist.
“They may even need to consider postponing travel or at least take special precaution, especially during winter when pollution levels can be extreme.”
Numerous studies have confirmed persistent air pollution increases the risk of asthma, cardio-vascular events, strokes and lung cancer. However, the new data revealed a stronger link between both indoor and outdoor air pollution exposure and cardiovascular diseases, such as strokes and ischaemic heart disease, as well as air pollution and cancer.
Health risks higher in winter
Modern-day smog is the result of emissions from petrol-powered cars and industrial fumes, which react with sunlight in the atmosphere to form secondary pollutants. These then combine with the primary emissions to form photochemical smog.
Typically, the health risks of smog and haze increase in winter when temperature inversion (a layer of warm air over cooler air) occurs, trapping the smog in the moist, cold air close to the Earth’s surface. What makes inversion-trapped smog even more unhealthy is that it combines smoke from its ever-increasing number of power stations with auto and industrial emissions.
Regionally, low- and middle-income countries in the WHO South-East Asia and Western Pacific Regions had the largest air pollution-related burden in 2012, with a total of 3.3 million deaths linked to indoor air pollution and 2.6 million deaths related to outdoor air pollution.
Each winter in many parts of South Asia, the burning of fossil fuels, combined with vehicle and factory emissions, creates ever-thicker smog for longer periods.
To the south-east, deliberately lit forest fires in Sumatra send thick smoke across the rest of Indonesia, Malaysia and Singapore.
Air quality matters – inside or out
According to the following WHO data, the breakdown of fatalities revealed that outdoor air pollution resulted in more heart disease, while indoor pollution from fuel stoves and other sources cause twice as many lung disease-related deaths.
Outdoor:
- 40% – ischaemic heart disease;
- 40% – stroke;
- 11% – chronic obstructive pulmonary disease (COPD);
- 6% - lung cancer; and
- 3% – acute lower respiratory infections in children.
Indoor:
- 34% - stroke;
- 26% - ischaemic heart disease;
- 22% - COPD;
- 12% - acute lower respiratory infections in children; and
- 6% - lung cancer.
The WHO says the release of the latest data is a significant step in advancing a roadmap for preventing diseases related to air pollution.
Later this year, the WHO will release an update of air quality measurements for 1600 cities across the globe, as well as developing a global platform on air quality and health to generate better data on air pollution-related diseases.
How you can reduce smog’s impact
Travellers visiting a smog- or haze-affected city can take steps to reduce the potential impact of air pollution.
BE PREPARED – In the days leading up to your departure, check the weather forecast in the city or region you are visiting. Wherever air quality is an issue, the weather forecast also includes the latest air pollution readings and a forecast for coming days.
MINIMISE TIME OUTDOORS – If travel can’t be avoided or postponed, stay indoors until conditions outside improve, keeping your hotel room’s windows and doors closed. Turn your room’s air conditioner to ‘recirculate’ mode. Some hotels have air purifiers available for guests – check with reception desk staff.
AVOID HEAVY EXERCISE OUTSIDE – Physical exertion increases the risk of airborne particles making their way deep into your lungs. If air quality is poor, avoid cycling, tennis, jogging, or other strenuous activity – especially near heavy road traffic or during the afternoon when ground-level ozone reaches its peak.
CARRY A MASK – If medium-high air pollution levels are forecast, consider wearing a mask. Better quality masks, such as N95 respirators, are far more effective than cloth or gauze masks at filtering small particles, although they don’t protect against noxious gases. (If you have an underlying medical problem, in particular a heart or lung condition, consult your doctor before using a mask.)
KEEP MEDICATION HANDY – If you use an inhaler or carry medication for a chronic condition, carry them in your hand luggage so they’re handy on arrival. Your inhaler and a dose of medication should go with you if you’ll be away from your hotel for the day or overnight.
REMEMBER TO PACK… Over-the-counter saline solution or eye drops to relieve irritated eyes.
Finally, if respiratory symptoms persist after you return, consult your doctor.
There’s more advice and information on the impact of poor air quality on health on the WHO website.
Find out about all of the potential health risks for your destination during a consultation with travel health professionals at our nearest Travelvax Australia clinic. To learn more contact our obligation-free advisory service on 1300 360 164 (toll-free from landlines).