Hanoi has been ranked the second most polluted city in Southeast Asia on the basis of incomplete data, says Vietnam.
Vo Tuan Nhan, deputy minister of Natural Resources and Environment, said at a Tuesday press conference that the World Air Quality Report released early last month, which says Hanoi had the second worst air quality in Southeast Asia, is not precise.
The report surveyed air quality in over 3,000 cities globally by measuring PM2.5 levels, referring to particulate matter of up to 2.5 micrometers (PM2.5) in size data, regarded as the pollutant with the most health impacts.
In Southeast Asia, however, data has been used from 20 cities in four countries – Indonesia, Thailand, the Philippines and Vietnam.
“Due to the lack of full data from 11 Southeast Asian countries, there’s no convincing evidence to jump to a conclusion that Hanoi is the second most polluted city in Southeast Asia,” Nhan said.
Nhan admitted that the concentration of PM2.5 in Hanoi has exceeded the permitted level, but only on some days, especially in the first three months of 2019, and the pollution was not widespread.
PM, or particulate matter, is the term for a mixture of solid particles and liquid droplets found in the air. PM2.5, also described as super fine particles, is a fraction of the width of a human hair, which is released from vehicles, industry and natural sources like dust.
Nhan blamed Hanoi’s worsening air quality on dense traffic, emissions from construction projects, industrial facilities and waste burning.
The ministry will work closely with the city’s leaders to take more feasible measures to improve air quality in the capital, he said.
He also said that in the coming time, the ministry is planning to install 80 more automatic air monitoring stations across the city, allowing the public to keep track of air quality every day.
The World Air Quality report compiled by Greenpeace and Switzerland-based air quality monitor IQAir AirVisual showed the average PM2.5 level in Hanoi last year was 40.8 micrograms per cubic meter of air as opposed to 45.8 in 2017. The World Health Organization (WHO) Air Quality Guideline recommends an annual mean exposure threshold of 10 μg/m3 to minimize health risks.
Although Hanoi has seen the improvement in air quality over the past year, it remained among the most polluted capital cities in the world, the report said, ranking it 12th among the 62 most polluted cities globally in 2018 and second in Southeast Asia, after Indonesia’s Jakarta.
The 2018 Sustainable Cities Index, commissioned by Arcadis, an Amsterdam-based design and consultancy firm, ranked Hanoi among the least environmentally friendly cities in the world.
The city of eight million people has more than five million motorbikes and 550,000 cars. Data shows the number of private vehicles has been increasing at a rate of 4.6 percent annually, but the amount of land allocated for transportation projects has only been expanding at a rate of 0.4 percent.
In its pollution fight, the city legislature made a controversial decision last July to approve a ban on motorcycles by 2030.
The ostensible aim was to boost use of public transportation, including a new metro system, but this is a poorly developed sector in the capital city.
Source: Tuoitrenews