Kathmandu-Asia and the Pacific have made significant progress in reducing vehicle emissions despite rapid economic growth, according to analysis by James Leather, Director at  the Asian Development Bank Transport Sector Office.

Between 2000 and 2022, GDP and vehicle ownership rose sharply, while harmful pollutants like PM2.5 declined, driven by stricter fuel and emission standards across the region.

However, the ADB warns that this progress is fragile. Rising vehicle numbers, especially motorcycles, and limited access to public transport are increasing reliance on private vehicles. At the same time, a new threat is emerging from non-exhaust emissions—such as tire, brake, and road wear—which now account for a growing share of pollution.

Diesel trucks and buses remain major contributors, producing more than half of PM2.5 emissions despite making up a small portion of vehicles. Weak regulation of used-vehicle imports is also worsening air quality in lower-income countries.

The report highlights domestic shipping as the fastest-growing source of transport-related pollution, largely due to the use of high-sulfur fuels and limited oversight. Similarly, electrification of transport has had limited benefits where power grids still rely on coal, effectively shifting pollution rather than eliminating it.

According to the ADB, poor air quality caused 7.9 million premature deaths in 2023 and economic losses of around $4.3 trillion annually in the region. The bank stresses the need for a shift from tailpipe-focused policies to broader, system-level transport reforms, including cleaner fuels, regulation of non-exhaust emissions, and investment in sustainable public transport.

The ADB concludes that while Asia has proven economic growth can be decoupled from pollution, urgent action is needed now to sustain progress and address emerging risks.