Heavy smog blanketed most areas in Beijing and air pollution readings surged after enthusiastic residents set off fireworks to celebrate the annual Lantern Festival, Xinhua reported  on Monday.
Readings of PM2.5, tiny airborne particles that can enter deep into the lungs, climbed to more than 300 micrograms per cubic metre in most areas in Beijing on Sunday night, coinciding with the last rush hours of firework displays, said the Beijing Municipal Environmental Monitoring Centre.
In certain areas, the level reached as high as 561, regarded as “severely polluted”. The World Health Organisation recommends that PM2.5 levels be kept below 25 micrograms per cubic metre.
Starting on Monday morning, no fireworks were allowed in Beijing's downtown until the next Lunar New Year, according to safety regulations on fireworks.
Beijing authorities on Sunday issued a smog alert and called on residents to reduce the smoky celebrations and stay indoors.
Experts said Sunday's weather condition also contributed to the sudden worsening air quality. A cloudy, foggy day with little wind appeared to prevent the pollution from blowing away.
After being told to reduce firework displays, people took to the internet to complain.
“Fireworks are the straw that broke the camel’s back. What’s really behind the air pollution were vehicles and factories. Cracking down on firework displays is only an environmental protection campaign, nothing more,” one internet user said online.
Beijing’s air quality has frequently made headlines in the last several months. The government has vowed to put in place more measures to combat air pollution in the capital by temporarily close down factories and restricting vehicles on roads.