© Digital Trends

© Digital Trends

Tourists visiting Beijing in the hope of seeing the city's famous landmarks will be lucky to see anything at all at the moment as the Chinese capital struggles with a particularly acute episode of air pollution. In fact, it's so bad that officials have in recent days been forced to issue their first ever "red alert" warnings.And for residents who have to endure severely toxic air sometimes several times a year, the situation must surely be a whole lot grimmer.Helping to provide Beijing citizens with some much-needed respite from the suffocating smog, and possibly make a few bucks in the process, aThe company, Vitality Air told CNN that its first batch of 500 canisters sold out in less than two weeks when it went on sale on a Chinese e-commerce site last month.Those who spend up to $20 for a can are able to treat their straining lungs to pure, clean air taken direct from the Rocky Mountain town of Banff, about 60 miles west of Calgary.Moses Lam, the startup's co-founder, said the idea of selling fresh air came to him last year when he managed to sell a bag of ziplocked air on eBay for 99 cents.As absurd as it may sound, Lam told CNN he visits Banff every few weeks from his base in Edmonton to "hand bottle" the air, which he then exports to China.He added, "We're dealing with fresh air, we want it to be fresh and we don't want to run it through machines which are oiled and greased."Vitality Air, which has been in business for around six months, sells some of its bottled air to customers in Canada, but mainly as a fun gift (don't they have enough of the stuff already? Like, out there?). However, the fact that some folks in China's worst-polluted cities are prepared to spend out for it appears to reflect the severity of the situation, or indicates that their sense of humor has been warped by the murky outside air.Some of the testimonials on the startup's website certainly make for an amusing read. "Air, as it was meant to be," says one, while another comments, "I love my Banff air, respiration is just more fun now."Striking a note of caution, Hong Kong-based pollution expert Professor Wallace Leung told CNN that bottles of fresh air would do little to ease the plight of those living in Beijing and other polluted cities, suggesting that the focus should instead be on filtering out poisonous particles - what he calls the "invisible killers" - emanating from factories, vehicles, and other sources.