Bhutan

While Bhutan historically enjoyed pristine air quality, urbanization and industrial activities have begun to strain air conditions, particularly in cities and industrial zones. The number of vehicles in Bhutan increased by 61% between 2015 and 2022, leading to rising emissions from transport. Industrial emissions have also grown by 60% between 2010 and 2022, primarily from the cement industry, metal production, and industrial processes. The country experiences an annual mean exposure of 23.9 µg/m³—4.8 times the WHO's recommended guideline. The health impact is severe, with 78 deaths per 100,000 people attributed to fine particle pollution in 2019, totaling 430 deaths nationwide. In Pasakha, particulate matter pollution was severe enough to force the relocation of a local school. Other key pollution sources include construction, forest fires, and transboundary pollution, with estimates suggesting that 80% of Bhutan’s air pollution originates from neighboring countries. Pollution levels worsen during winter due to atmospheric conditions that trap pollutants and the increased use of wood fires for heating.

Despite Bhutan’s environmental policies, air quality management faces multiple challenges. Limited financial resources, institutional capacity, and technical expertise hinder the implementation of effective pollution control programs. Transboundary pollution remains a major issue, requiring regional collaboration to address shared air quality concerns.

Monthly mean PM2.5 concentrations in Bhutan across multiple years exhibit a distinct seasonal trend. Average PM2.5 levels peak during the winter months (December to February), often exceeding 30 µg/m³, and significantly decrease during the mid-year months (May to August), dropping to around 10 µg/m³. Regarding the maximum variability in PM2.5 by month over the years, PM2.5 concentrations show high variability during the winter months, frequently spiking well above the mean values, while the mid-year months have lower, more stable pollution levels.

For industries, cleaner technologies have been promoted and adopted, especially in the food and beverage sector. The country is now 99 per cent electrified by hydropower, and wind and solar power is also being pursued where possible. Yearly mean PM2.5 levels in major cities of Bhutan show moderate pollution levels, with Gelephu and Phuentsholing recording the highest concentrations, fluctuating between 35-50 µg/m³. Chang and Wangchang have consistently lower levels, ranging from 15-20 µg/m³. Despite relatively better air quality compared to other South Asian cities, PM2.5 levels in all locations remain above the WHO standard, indicating ongoing air pollution challenges influenced by local emissions and regional pollution transport.

To combat pollution, Bhutan has implemented strict environmental regulations, including mandatory Environmental Impact Assessments (EIA) for development projects and the Environment Standard 2020, which imposes stringent air quality standards. The National Environment Strategy 2020 aims to expand air quality monitoring, promote low-emission transport, enforce stricter vehicle emission controls, and develop renewable energy sources. Progress has been made in expanding air quality monitoring, with automated stations established in Thimphu, Pasakha, Phuentsholing, Chele La, and Gedu. Bhutan has also promoted public transport and electric vehicles, offering direct subsidies, low-interest loans, tax breaks, import duty exemptions, and charging infrastructure development , awareness campaigns  and capacity building for electric vehicle technicians. The import of Euro VI and Bharat Stage VI vehicles is also allowed with stricter emission controls. 
 
Looking ahead, Bhutan has prioritized regional air quality monitoring and data-sharing networks, joint action plans with neighboring countries to mitigate transboundary pollution, and capacity-building initiatives to strengthen air quality management. While these efforts demonstrate Bhutan’s commitment to clean air, sustained collaboration and financial support will be essential for long-term success.