Cao Tung Son, Director of the Center of Environmental Monitoring under the municipal Department of Natural Resources and Environment, said at a press conference Wednesday that traffic was responsible for the most part of the pollution considering the large number of vehicles on the city’s roads.

There are 37 traffic jam hotspots in the city that generate a huge amount of emissions, he said.

Data from 19 traffic locations show that more than 50 percent of the pollutants are suspended dust. High concentrations of pollutants above the safety level are regularly recorded at Cat Lai in District 2, Huynh Tan Phat - Nguyen Van Linh intersection in District 7 and intersections connecting the city to its western and eastern neighbors.

Among them, My Thuy roundabout in District 2 was the most polluted spot in the city.

The environmental monitoring center used air quality monitors at 30 spots for 10 days every month for the last nine months at two time frames: 7:30 to 8:30 a.m. and 3 to 4 p.m.

The center's director admitted that the slow release of the monitoring results was a drawback. He said the monitoring was done manually and this, combined with the need to collect samples and analyze them, made it a time-consuming process.

In 2020, the city will have nine automatic, non-stop air monitors that are secured in nine locations. One additional automatic monitor will be moved around. This will allow the results to get to the public faster, Son said.

The city will also build specialized software to provide information about the environment’s quality to the citizens on a daily basis through mass media and smartphones. It also plans to make forecasts about air pollution, he added.

Son said that the monitoring data released by AirVisual was not completely accurate, saying the organization had miscalculated the data in adverse weather conditions.

A product of Switzerland-based air quality monitoring facility IQAir AirVisual, many Vietnamese people have relied on their AirVisual app to keep track of the air quality over the last two months.

Air quality indexes displayed on the app are updated every hour. Pollutants are measured and based on the U.S. Air Quality Index value. The application collects data from 14 air control stations in Hanoi and seven stations in Ho Chi Minh City.

Amidst public concern, the government has called on Hanoi and HCMC to devise a clear and radical strategy to combat the worsening pollution and to keep it notified.

"We must not let the public complain without proposing an effective solution," Prime Minister Nguyen Xuan Phuc told authorities in the two cities and the Ministry of Natural Resources and Environment last week.

The press conference took place almost one month after September 22, when a blanket of haze began enveloping HCMC.

The thick haze covered iconic towers like Landmark 81, Vietnam’s tallest building with 81 floors, and 68-floor Bitexco tower in downtown area. It was so thick that the buildings could not be seen from 300 meters away.

The haze is yet to lift from the city.