In accordance with the World Health Organization's guidelines, the air quality in Nepal is considered unsafe - the most recent data indicates the country's annual mean concentration of PM2.5 is 100 µg/m3, exceeding the recommended maximum of 10 µg/m3.
Contributors to poor air quality in Nepal include the manufacturing and construction industries, vehicle emissions, and waste burning. Seasonal variations in pollution exist, with the highest levels in the dry season (December to April).
Air pollution levels can also vary at different altitudes, with high levels occurring in the morning and evening in plain and valley locations, and during the afternoon in high altitude locations. Available data indicates that Kathmandu has consistently unsafe levels of air pollution due. The city is located in a valley, where polluted air often gets trapped. Lumbini, Nepalgunj, Bhairahawa, and Chitwan are also cities with consistently high levels of air pollution.
Outdoor air pollution is a mix of chemicals, particulate matter, and biological materials that react with each other to form tiny hazardous particles. It contributes to breathing problems, chronic diseases, increased hospitalization, and premature mortality.
The concentration of particulate matter (PM) is a key air quality indicator since it is the most common air pollutant that affects short term and long term health. Two sizes of particulate matter are used to analyze air quality; fine particles with a diameter of less than 2.5 µm or PM2.5 and coarse particles with a diameter of less than 10 µm or PM10. PM2.5 particles are more concerning because their small size allows them to travel deeper into the cardiopulmonary system.
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.
Cities and rural areas worldwide are affected by air pollution. When planning a trip, consider health status, age, destination, length of trip and season to mitigate the effects of air pollution.
Short term symptoms resulting from exposure to air pollution include itchy eyes, nose and throat, wheezing, coughing, shortness of breath, chest pain, headaches, nausea, and upper respiratory infections (bronchitis and pneumonia). It also exacerbates asthma and emphysema. Long term effects include lung cancer, cardiovascular disease, chronic respiratory illness, and developing allergies. Air pollution is also associated with heart attacks and strokes.
- Comply with air pollution advisories - ask around and observe what locals are doing and avoid strenuous activities.
- Travellers with asthma or chronic obstructive pulmonary disease (COPD) should carry an inhaler, antibiotic, or oral steroid - consult your doctor to see what is best for you.
- Older travellers with pre-existing conditions should get a physical exam that includes a stress and lung capacity test prior to departure.
- Newborns and young children should minimize exposure as much as possible or consider not travelling to areas with poor air quality.
- Ask your medical practitioner if a face mask is advisable for you.
See city and country air pollution levels:
Information last updated: April 16, 2020