Smoking is one of the leading causes of indoor air pollution. (Photo : Getty Images)
Citing a World Health Organization (WHO) data, the Global Times reported that indoor air pollution is more dangerous and deadlier than the one outdoors.
The WHO report stressed that each year, 4.3 million deaths occur due to indoor air pollution exposure. The figure is higher than the 3.7 million deaths caused by outdoor air pollution.
The data comes as summer continues to heat up.
"I'm tired of waking up to a disgusting and suffocating smell. But that's always the beginning of my day," Wang Jinchen, a postgraduate student at Beijing Foreign Studies University, shared.
Since the onset of the summer season, Wang said that she has become more uncomfortable indoors. At this period, indoor air pollution is at its peak as high humidity and temperture help increase the growth of illness-causing bacteria indoors.
When too concentrated, indoor pollutants can cause people to develop allergies as well as respiratory diseases.
"If it is not that hot, I would stay outside because I think the air is better outdoors--unless there is severe smog," she further said.
According to Dai Zizhu, a research fellow affiliated with the Chinese Center for Disease Control and Prevention, Beijing residents should pay more attention to this issue.
"Indoor air pollution will increase in accordance with that outdoor, especially in Beijing, where the smog is so severe," Dai stated.
Sharing the same sentiment, Song Guangsheng, the vice president of the China National Interior Decoration Association, noted that "people breathe in four times as much particulate matter indoors than outdoors in Beijing because they spend 70 to 90 percent of their time indoors."
A Tsinghua Univeristy study released last year listed smoking and cooking as some of the leading causes of indoor air pollution, a 2015 Xinhua News Agency report cited.
The article urged people to open their windows and doors to help fresh air circulate, particularly when the outdoor PM2.5 is lower than 75 micrograms per cubic meter.
In addition to the mentioned causes, indoor air pollution can also be exacerbated with the heavy use of air conditioning as it reduces air flow. Apart from this, air conditioning units can also cause secondary air pollution indoors because of the large amounts of mold and bacteria that accumulate inside.
A 2013 Xinmin Weekly report cited a study from Germany's TUV Rheinland suggesting that indoor humidity should be kept at around 40 to 50 percent to prevent the accumulation of mold and other dangerous microorganisms.
