In many parts of the world, poor air quality is a significant public health problem. The health effects of air pollution are complex; studies have shown exposure to high levels of air pollution over short time periods (e.g. minutes/hours/days) and longer time periods (e.g. years) is linked to many different acute and chronic health problems. These effects are mainly on the respiratory and cardiovascular systems. Air pollution is a complex mix of particles and gases, and concentrations of pollutants are often highest in the urban areas of low- and middle-income countries. Particulate matter (PM) and nitrogen dioxide(NO2) are both major components of urban air pollution. Current information on world air quality is available from a number of sources including World Health Organization (WHO), AirNow and World Air Quality Index Project.

Prevention

Travellers with respiratory and cardiovascular conditions should consider whether a particular destination is appropriate for them if pollution levels are known to be high during their planned stay.

In areas where poor air quality is a concern, all travellers should:

• On a day to day basis, check the local air quality data and adjust activities to help plan their outdoor activities e.g. avoid exercising outdoors when pollution levels are high, avoid pollution hot spots if possible such as  busy roads/junctions, rush hours, keep external doors and windows closed when air pollutant levels are high
• Take notice of any Health Advisories published by the Local Ministry of Health and Department of Environment, and follow the guidance provided

It is unclear if face masks are beneficial at reducing exposure and may make breathing more difficult for those with pre-existing lung conditions. Those who choose to use a mask should make sure that it fits well and know how to wear it properly.

Resources

• Public Health England Health Matters: Air Pollution
• WHO Air quality guidelines - Global update 2005. Particulate matter,, ozone, nitrogen dioxide and sulfur dioxide
• British Lung Foundation: Air Pollution