Vietnam's air quality improves but has not met WHO standard

The decline in the annual average PM2.5 concentration continued in 2021, falling to 24.7 μg/m3 after peaking in 2019 at 34.1, the World Air Quality Report by Swiss technology and monitoring company IQAir said.

The report, released Tuesday, contains PM2.5 air pollution data from ground-based monitoring stations in 6,475 cities in 117 countries, regions and territories.

The figure for Hanoi decreased by 4.5 percent to 36.2.

HCMC did much better, with the PM2.5 concentration falling from 22 to 19.4.

However, despite declining concentrations, none of the 13 Vietnamese cities included in the report met the annual average WHO PM2.5 air quality guideline concentration of 5 μg/m3, IQAir said.

The 13 cities are distributed all over the country from Thai Nguyen, Hanoi and others in the northern plains to Long Xuyen in the Mekong Delta in the south.

Thai Nguyen in the eponymous province was the most polluted at 40.8 μg/m3, while at the other end Ha Long was a relatively clean 10.7.

Among capital cities sorted in descending order Hanoi was in 15th place out of 107.

HCMC ranked 1,179th globally, and 109th out of 227 in Southeast Asia.

In the country ranking, Vietnam was in 36th place of the 117, and New Caledonia was in 117th with 3.8.

In Southeast Asia there was a slight overall reduction in PM2.5 levels of around 5 percent.

Two of the region's 10 most populated cities, Jakarta in Indonesia and Hanoi, had PM2.5 levels that were seven times higher than recommended by the WHO guidelines.

Jakarta had the highest number in the region of 39.2.

In September 2021 WHO released an update to its global air quality guidelines, 15 years after its last one in 2006.

Acknowledging the significant impact of air pollution on global health, it cut the recommended annual PM2.5 limit by half to 5 μg/m3 with the ultimate goal of preventing millions of deaths.

It is estimated that last year the deaths of 40,000 children under the age of five were directly linked to PM2.5 air pollution.

Besides, researchers have found evidence that exposure to PM2.5 increases both the risk of contracting Covid-19 and of suffering more severe symptoms when infected, including death, the report said.

IQAir said Vietnam's usage of fossil fuels for power generation is a primary cause of air pollution, along with exhaust from cars and motorbikes and factory emissions.

As manufacturing activity increased, the country's economy has grown over the past decade, increasing the demand for electricity.

In 2020 half of all electricity was generated by coal-fired plants.

Vietnam promised to reach carbon neutrality by 2050 at last year's U.N. COP26 conference, the report pointed out.

"With the largest solar power infrastructure in Southeast Asia and the addition of offshore and onshore wind farms, Vietnam is poised for a transition away from the use of fossil fuels to power its growing economy.

"Actions to achieve carbon neutrality will also have the co-benefit of improving air quality by reducing the use of fossil fuels, the country's major source of air pollution."

At a regional level, the report said rapid population growth and the accompanying economic development have been significant factors in increasing air pollution.

Oil and coal are the biggest sources of fuel in the power sector, and with the demand for electricity growing at around 6 percent a year, the combustion of fossil fuels is a primary contributor to PM2.5 concentrations.

Globally, Delhi in India, Dhaka (Bangladesh) and N'Djamena (Chad) had the worst air quality in 2021, while Noumea (New Caledonia), Charlotte Amalie (U.S. Virgin Islands) and San Juan (Puerto Rico) were the cleanest.

Only 3 percent of cities and no country met the WHO guidelines.

Frank Hammes, CEO of IQAir, called the finding "shocking," and said the report underscores just how much work remains to be done.

"The time for action is now."