Locals make smoked bacon in Sichuan. [Photo/Sina weibo]

While experts point to car emissions and city construction for causing foul air, a government official in a southwest China city has laid the blame on people making smoked bacon.

The city of Dazhou in Sichuan province has endured heavy smog since the new year began, with the PM 2.5 reading frequently exceeding healthy levels.

Rao Bing, deputy head of Dazhou Environment Protection Bureau, said on January 4 that one of the causes of the city's lingering smog is smoking bacon, a traditional method of preserving pork by local residents.

Eating preserved pork and sausages is a long-held tradition in Sichuan, and almost every household makes smoked bacon before the Chinese lunar new year, which falls on Feb. 19 this year.

Local chengguan, or public civil servants, have started to raid and forcibly demolish meat-smoking sites.

The claim invited public ridicule and skepticism after Rao's statement found its way online on Wednesday.

On Sina Weibo, netizens mocked the official's argument by saying that Dazhou's air might "smell like smoked bacon."

"Smoking bacon has a long history, but smog does not," said one comment.

Smoking meat does contribute to air pollution, but only to a small degree, according to volunteers at Bayu Public Welfare Development Center, a non-government environmental protection organization, which conducted a three-day survey at a dozen bacon-smoking sites.

"The impact of the smoking process is confined within a 50-meter radius," a volunteer told the Chongqing Evening News.

It is not the first time that Chinese government officials have suggested controversial explanations for smog. In October, environmental watchdogs in Beijing and the adjacent Henan province, two severely polluted places, blamed the smog on farmers burning straw, an agricultural practice with a long history.

In recent years, swathes of the country have frequently reported heavy smog, slashing visibility and posing health hazards. China has taken a variety of measures to contain severe air pollution, including restricting industrial production and vehicle use.