Hanoi residents are inhaling the equivalent of two cigarettes daily
Hanoi is in the midst of its third major pollution episode of the season, and new data shows that residents are now inhaling the equivalent of two cigarettes every day.
According to the latest forecast from HanoiAir, an AI-based air-quality model developed by the Intelligent Geospatial (GEOI) research group at Vietnam National University, the current smog event began on November 28 and may persist until December 5.
On Monday morning, Hanoi’s average AQI reached 143, placing the city firmly in the “poor” category. This corresponds to PM2.5 concentrations of 77 µg/m³ — five times higher than the World Health Organization’s guideline of 15 µg/m³.
Multiple monitoring stations run by the Environment Department also reported rapid rises into the “unhealthy” and “very unhealthy” ranges across the capital. These readings reflect PM2.5 levels, the pollutant widely recognized as the most harmful driver of urban air pollution.
Two Cigarettes a Day — Through the Air Alone
A widely cited 2015 study by Berkeley Earth found that breathing air with 22 µg/m³ of PM2.5 over 24 hours causes health damage similar to smoking one cigarette. Using WHO’s recommended limit of 15 µg/m³, the exposure equals roughly 0.7 cigarettes.
Applying this calculation to 2024 PM2.5 data across Hanoi’s wards and communes, GEOI researchers estimate that the average resident is effectively inhaling two cigarette-equivalents per day, based on an annual mean PM2.5 concentration of 41 µg/m³. During severe winter smog episodes, this number increases significantly.
A Widespread Public-Health Burden
The impact is profound. WHO has consistently labeled air pollution a “silent killer.” World Bank data from 2021 show that 40% of Hanoi’s population (about 3.5 million people) were exposed to PM2.5 concentrations above 45 µg/m³, more than five times the global guideline. In Hanoi, PM2.5-related diseases were linked to 32% of all deaths, equivalent to roughly 5,800 fatalities annually.
Health professionals are already observing the fallout. Dr. Doan Du Manh from the Vietnam Vascular Disease Association notes that exposure to outdoor air during severe smog episodes can cause harm comparable to smoking two packs of cigarettes per day.
PM2.5 particles, just 1/30 the width of a human hair, can travel deep into the lungs, inflame major airways, and lodge in the alveoli, where they contribute to long-term scarring. Spikes in respiratory infections, strokes and cardiovascular complications consistently appear between September and December, when winter weather patterns collide with peak pollution levels.
Sensitive groups are the most vulnerable: children, older adults, pregnant women, and those with chronic respiratory conditions often experience repeated sinus infections, sore throat and, in severe cases, acute bronchopneumonia.
A Regional Issue, Not Only Hanoi’s
AirVisual and GEOI data since 2019 indicate that during peak pollution months, residents in northern Vietnam are exposed to the equivalent of three to four cigarettes per day.
Globally, Hanoi ranked 7th in AirVisual’s 2024 report with an annual PM2.5 level of 45.4 µg/m³. New Delhi topped the list at 91.8 µg/m³ (about 4.2 cigarette equivalents), followed by N’Djamena, Chad at 91.6 µg/m³.
Experts warn that worsening air quality is no longer limited to northern regions. Ho Chi Minh City and surrounding provinces are increasingly showing similar degradation trends.
Forecasting and Policy Responses
Experts emphasize that air-quality forecasting should become a routine part of daily life. Pollution can now be predicted 7–9 days in advance, making AQI checks as essential as weather updates.
Authorities are implementing short-term protective measures. Since November 27, the Ministry of Agriculture and Environment has requested the Ministry of Industry and Trade to direct steel, chemical, fertilizer and thermal-power plants across northern Vietnam to reduce production or postpone major operations on days when AQI exceeds 200. The Ministry of Education has advised schools to limit outdoor activities whenever air quality worsens.
Under Vietnam’s National Action Plan for Air Quality Management (2026–2030), Hanoi must cut PM2.5 levels by 20% compared to 2024 and increase the number of “good” or “moderate” days to at least 80%. By 2045, the city is expected to meet the national annual PM2.5 standard of 25 µg/m³.
Source: VNExpress