The Ministry of Health has advised Hanoi residents to limit outdoor activities, focus on indoor tasks, or postpone plans until air quality improves, as pollution levels in the capital continue to worsen.
The Air Quality Index (AQI) in Hanoi frequently reached “unhealthy” (101-200) and “very unhealthy” (201-300) levels on Tuesday and Wednesday.
Seasonal weather patterns and climate conditions contribute to the rising pollution, but monitoring data from the Ministry of Natural Resources and Environment indicates a gradual deterioration in air quality, posing risks to public health and socio-economic activities.
The World Health Organization warns that exposure to air pollutants increases the risk of acute respiratory infections, asthma, chronic obstructive pulmonary disease, cardiovascular disease, and stroke. Additionally, it can lead to skin damage, eye diseases, and negatively impact the nervous, immune, and mental health systems.
To protect public health, the ministry has outlined measures based on AQI levels.
Under “unhealthy” AQI, it advised people to limit outdoor activities, especially for vulnerable groups such as children, pregnant women, the elderly, and individuals with respiratory or cardiovascular conditions.
When AQI hits “very unhealthy” levels, people should avoid all outdoor activities and prioritize indoor tasks, wear masks designed to filter fine dust if outdoor activities are unavoidable, minimize time in polluted areas, and use public transportation when possible, it said.
Residents are also encouraged to close windows and doors during periods of heavy pollution, clean their noses, gargle, and rinse their eyes with saline solution after being outdoors. The ministry advised monitoring health conditions and seeking medical attention if symptoms like difficulty breathing, coughing, or fever occur.
According to Switzerland-based monitoring platform IQAir, Hanoi’s AQI was recorded at 219—categorized as “very unhealthy”—at 9 a.m. on Wednesday.
The PM2.5 concentration (particulate matter smaller than 2.5 microns) reached 144 µg/m³, which is 28.8 times higher than the World Health Organization’s recommended annual guideline.
IQAir predicted the air pollution would remain at “very unhealthy” levels until Wednesday afternoon.
Hanoi’s air quality began deteriorating in October 2024 as the city transitioned into winter.
Both the Ministry of Natural Resources and Environment and Hanoi authorities have implemented measures to reduce emissions. Traffic remains the largest source of air pollution, prompting plans to develop low-emission zones. For construction and road dust, the city has intensified cleaning and spraying measures.