Ambient air pollution is measured by the concentration of particulate matter 2.5 (PM2.5), a fraction of the width of a human hair which is released from vehicles, industry and natural sources like dust.  

Hanoi suffered from air pollution most of the days in the first quarter of this year 

The report based on the World Health Organisation standards indicated that during the January and March period, Hanoi had up to 82 days with PM2.5 concentration surpassing the WHO’s permitted level, on 91% of the period’s total days.

Hanoi suffered from this problem during 78 days over the same period of last year.

The air quality in Hanoi has tended to worsen this year as around 70% of the first quarter’s total hours were not good for health.

GreenID’s analysis showed that Hanoi ranked second among 23 cities in Southeast Asia with the highest air pollution surveyed in the first three months of 2018.

HCM City’s air quality was better than Hanoi with 68 days having the PM2.5 concentration higher than the WHO’s permitted level.

The WHO has recently announced that nearly 90% of the world’s population suffer PM2.5 concentrations which exceed the organisation’s recommended levels and up to seven million die of pollution related diseases.