Hanoi air pollution at hazardous level

The air quality index (AQI) in Hanoi stayed at an average level of 154 on Monday, according to the Switzerland-based air quality monitoring facility, IQAir AirVisual.

An AQI reading of above 100 is considered unhealthy for humans as it could cause respiratory diseases like pneumonia, bronchitis, and respiratory failure, especially among young children and the elderly.

On the three days of Nov. 4, 5 and 6, the index measured 157, 155 and 161 in the capital.

On Monday, Hanoi's neighbor Thai Nguyen Province is the most polluted locality in Vietnam, with an AQI of 176, followed by the capital and Ho Chi Minh City with an index of 137.

The air quality for both Hanoi and Thai Nguyen is expected to remain at "unhealthy" levels on Tuesday and Wednesday.

As recommended by AirVisual, people living in areas with "unhealthy" air quality should wear masks outdoors and avoid outdoor exercise.

Vietnamese environment monitoring app PAM Air also measured the AQI of Hanoi at hazardous levels, ranging between 150 to over 200 in different areas on Monday.

AirViusal said the main pollutant in Hanoi is fine dust PM2.5.

It said the city's PM 2.5 concentration as measured on Monday stood at 60.4µg/m³, which is 12.1 times the air quality guideline value recommended by the World Health Organization.

PM2.5 is defined as ambient airborne particulate that measures up to 2.5 microns in size, just a fraction of the width of a human hair. Their microscopic size allows these particles to be absorbed deep into the bloodstream upon inhalation, potentially causing health effects like asthma, lung cancer, and heart disease.

Exposure to PM2.5 has been linked to negative health effects like cardiovascular disease, respiratory illness, and premature mortality.

Hoang Duong Tung, chairman of Vietnam Clean Air Network, said the practice of rice field burning after harvest season in Hanoi is the main driver worsening air pollution in the capital.

Among other reasons for the situation is vehicle emissions, construction activities, and operation of industrial areas, he said.

A study published last year said life expectancy among Hanoians is reduced by 2.49 years on average due to exposure to fine particulate matter (PM2.5).

"Research on the impact of air pollution caused by PM2.5 dust on public health in Hanoi in 2019" by the Hanoi-based non-profit organization Live and Learn for Environment and Community (Live&Learn), Hanoi University of Public Health (HUPH), and Vietnam National University's University of Engineering and Technology is the first study to use data provided by local authorities to evaluate the burden of disease caused by impacts of PM2.5 dust pollution on public health in Hanoi.

The study said the number of premature deaths due to exposure to PM2.5 dust hit 2,855 cases, equivalent to about 35.5 premature deaths per 100,000 people while the life expectancy lost from exposure to PM2.5 dust totaled 908 days, or 2.49 years for Hanoians.