“The people who are doing the most to reduce emissions, by biking or taking the bus, were the people who experienced the highest levels of exposure to pollutants,” said Griswold.  

The ultimate goal of CitiSense is to build and deploy a wireless network in which hundreds of small environmental sensors carried by the public rely on cell phones to shuttle information to central computers where it will be analyzed, anonymized and delivered to individuals, public health agencies and the community at large. The sensors currently cost $1,000 per unit, but could easily be mass-produced at an affordable price. So far, Griswold’s team has built and deployed 20 of them in the field.

Technical challenges remain. The data exchanges between smart phones and sensors use up a great deal of the phones’ batteries. During field tests, researchers provided users with two chargers—one for home and one for work—to ensure that their phones were not going to run out of power.

via Small, Portable Sensors Allow Users to Monitor Exposure to Pollution on Their Smart Phones.