I don’t meant to be sensational, but I just got a picture from a friend of a friend who is pregnant and just started using the DIY filter three days ago. The filter is turning black already.
After all, scientific research suggests children are the most affected by air pollution. If the outrageous prices of filters are keeping pregnant women from cleaning their air, then the DIY filter has already started to change that.
Thomas is an Associate Professor of Behavior Science at the University of Chicago Booth School of Business and the founder of, a social enterprise to help people in China breathe clean air without shelling out thousands of dollars for expensive purifiers.