HONG KONG • A team of Chinese and American scientists have jointly produced an affordable - and environmentally friendly - air filter made out of soya beans.
The new invention can remove almost all the harmful particles that existing air filters were unable to remove, according to the South China Morning Post (SCMP).
The filter material could also be fitted into existing air filter machines, said Professor Zhong Weihong, a materials engineering professor at Washington State University.
She visited Beijing recently to find the Chinese capital shrouded in smog. "Air pollution is a very serious health issue," she said. "If we can improve indoor air quality, it would help a lot of people."
The new filter material is developed from natural purified soya bean protein, as well as bacterial cellulose, an organic compound produced by bacteria.
Prof Zhong said that the soya bean-based filter could remove most toxic chemical pollutants in the air, including carbon monoxide and sulphur dioxide - a feat that existing air filters had failed to achieve.
The new filter could remove more than 99.94 per cent of PM2.5 pollutants, fine particles in smog that are smaller than 2.5 microns in diameter and are most harmful to health.
The joint study by Washington State University and the University of Science and Technology Beijing will be published in the Composites Science And Technology journal.
Chinese consumers are snapping up record numbers of imported face masks and air purifiers as they struggle to combat the repeated bouts of smog that have hit northern China since late last year.
The global indoor air purification market is poised to almost double within 10 years, to US$21.8 billion (S$31 billion) by 2024, according to a report by Grand View Research. China was singled out as a pre-eminent driver behind the growth, according to SCMP.