Recent monitoring data show high PM2.5 (fine dust) levels in some Vietnamese cities, raising healthcare costs, economic losses, and policy pressures, according to Hoang Duong Tung, Chair of the Vietnam Clean Air Network.

Tung said at the “Reducing Emissions, Purifying Air” seminar organized by Thanh Nien newspaper on August 22 that air pollution causes economic losses of 5-7 percent of GDP as estimated by the World Bank and WHO. Vietnam sees tens of thousands of premature deaths annually linked to air pollution.

The main harmful effects of air pollutant exposure are respiratory, cardiovascular, ophthalmic, dermatological, psychiatric, hematological, immune, and obstetric. There is evidence indicating that air pollution affects molecular and cellular levels, leading to cancer in the long term.

In major cities like Hanoi and HCMC, PM2.5 levels often exceed permissible standards on many days of the year. Air quality indices frequently rank among the world’s worst.

“The situation is so bad that in recent years, besides spring, summer, autumn and winter, Hanoi residents talk of a ‘pollution season’ from October to April, marked by low rain, calm winds, high humidity, and temperature inversions that hinder dispersion,” Tung said.

Main culprit of pollution

According to Tung, PM2.5 fine dust comprises primary particles (dust, soot) and secondary particles (sulfate-nitrate-ammonium) formed from SO₂, NOx, VOCs, and NH₃ in the atmosphere, generated by human activities like fossil fuel transport, open burning (straw, waste), construction, and ammonia from agriculture.

Among these, transportation is the top cause of air pollution in most global cities. In Vietnam, the large number of vehicles, many of poor quality, contributes to rising emissions. Motorbikes are the primary source.

For example, in HCMC, motorbikes account for 35.3 percent, 91.4 percent, and 65.4 percent of NOx, CO, and SOx emissions from on-road sources, respectively.

“An old gasoline motorbike can emit CO, HC, NOx, and PM2.5 at levels 10-20 times higher than a car meeting Euro 4-5 standards,” Tung said, adding that delays in addressing this will increase damages and costs, making the situation harder to reverse.

Citing lessons from other countries, Tung noted that in 2013, China’s PM2.5 levels were about 90 µg/m³ (double Hanoi’s center over the past decade). In September 2013, China’s government launched an Air Pollution Control Action Plan focusing on green transformation (greening transport, industry, urban, and rural areas).

The plan significantly improved air quality, reducing PM2.5 levels by 33 percent in Beijing and 15 percent after four years (2013-2017). The University of Chicago reported that from 2014 to 2022, China reduced PM2.5 levels faster than any other country.

Tran Chung