China's Chen Guangbiao, the eccentric millionaire philanthropist known as much for his wacky charitable endeavors as for his generous humanitarian deeds, is reportedly making a killing in his "canned fresh air" business venture.

Chen, a millionaire believed to be one of China's richest individuals, recently began selling canned fresh air in response to Beijing's ever-worsening air pollution problem.

Offered in a variety of flavors, such as "pristine Tibet" and "post-industrial Taiwan," the air is being sold for about 5 Chinese Yuan ($0.80) a can.

"Every day, we are inhaling the exhaust fumes of cars," Chen told China's Sina News last year of his canned air idea. "And now we have pollution-free air to sell -- a benefit to everyone's health and longevity."

Though Chen's idea was initially seen by some as an outlandish publicity stunt or a mere novelty, it appears that his promise of fresh, clean air has become irresistible to many urbanites, wrapped this week in an unusually thick blanket of toxic smog.

On Friday, Want China Times reported that Chen has sold "more than 8 million cans" of fresh air over the past 10 days, as particularly poor air quality has been forcing residents of several cities in China, including Beijing, to seek protection indoors or behind surgical masks. The severe air pollution has reportedly also caused a spike in patients suffering from respiratory diseases.

In addition to selling millions of cans (the proceeds of which will go to charity), Chen has reportedly been taking to the streets to give away cans of fresh air for free.

"Come on, two cans for each one -- free fresh air. Open it and drink it and breathe it! It keeps you fresh the whole day," Chen said to passers-by as he gave away cans of air in Beijing, according to the Guardian.

With a tainted Beijing sky, heavy with smog, as a backdrop, city folk can be seen in the Reuters video (above) grabbing what clean air they can, before bringing the cans to their noses or mouths for a breath of something fresh.

This week, the Toronto Star reported that air pollution had reached "hazardous" levels in China's capital, causing the cancellation of flights and the shutdown of factories. The newspaper, quoting the American embassy in China, wrote the following on Tuesday:

Peak levels of PM2.5 -- microscopic particulate matter that can embed deep into the lungs and pose a serious health risk — were 526 micrograms per cubic metre over a 24-hour period, according to the embassy’s monitoring station in Beijing. The level recommended by the World Health Organization is just 25 micrograms per cubic metre.

According to a 2012 study by Greenpeace and Peking University’s School of Public Health, PM2.5 air pollution may have led to 8,572 premature deaths in four major Chinese cities, including Beijing, last year.

Chen, an active environmentalist, has long championed the need for better air pollution control.

"If we don't act in the next 10 years, our descendants will have to carry oxygen tanks and wear masks all the time," he said, according to the Guardian.