According to the Department of Environmental Pollution Control (Ministry of Natural Resources and Environment), air pollution is an existing problem in Vietnam, focusing on two key economic regions in the North (around Hanoi) and the South (around Ho Chi Minh City).
Pollution is seasonal (from around October-November of the previous year, lasting until April of the following year) and is mainly concentrated in some areas with high traffic density and many production facilities. During the day, the pollution level also fluctuates, concentrated between 6-8am and 5-7pm.
The causes of air pollution in Vietnam are determined to focus on the following main groups of emission sources: From transportation activities; construction activities; industrial production activities; open burning activities; civil activities, use of honeycomb coal stoves in daily life and business; and climate and weather conditions.
The Department of Environmental Pollution Control said that the monitoring results at automatic, continuous air environment monitoring stations (Monitoring stations) in urban areas from 2022 to 2023 showed that the average annual PM2.5 dust value at monitoring stations in Hanoi city, monitoring station in Que Vo (Bac Ninh province), monitoring station in Hung Vuong (Thai Nguyen city) all exceeded the permissible limit according to QCVN 05:2023/BTNMT.
PM2.5 dust values observed in areas across the country have a strong differentiation between regions. PM2.5 dust values are highest in Hanoi and neighboring provinces in the Red River Delta, followed by Ho Chi Minh City and surrounding provinces. PM2.5 dust values are lowest in provinces in the Central Highlands and Southwest regions.
In the Northern region, PM2.5 dust values often increase from October to March of the following year, causing air pollution. Air pollution is often recorded before and after cold air waves and often increases dramatically at night and early morning. The reason is that in winter in the North, unfavorable meteorological conditions such as low rainfall, calm weather, and temperature inversion prevent fine dust from dispersing, causing air pollution in the region.
On the contrary, meteorological conditions in the summer such as high wind speed, heavy rain, and strong atmospheric convection wash away and diffuse dust in the air, so the concentration of fine dust is lower. In 2024, up to the end of October, Hanoi recorded a total of 4 periods of severe air pollution, including 3 periods from January to April and 1 period in early October.
