CitiSense aims to improve air quality data with wearable sensors

By MHN Staff

CitiSense Air Quality Field Study AppBy Padma Nagappan

While healthcare is shifting from provider-centered episodic care to outcome-based, patient-centered care, at least one speaker at last week's Wireless Health 2012 event believes that more personalized air quality data should be a part of the healthcare discussion, too. In chronic conditions like asthma and cancer, environmental exposures play a major role in disease development, yet care givers and public health officials only have sparse regional measurements of the environment that give them bird's eye views.

Personal exposure to these factors can be measured with body-worn sensors and smartphones and when it's collected from many people and analyzed across an entire region, it can revolutionize how public health is practiced, say the researchers behind CitiSense.

"Studies have shown asthma is more prevalent in communities close to highways, yet 30 percent of our schools are built next to highways, so it's not surprising we have such a high incidence of asthma," one of CitiSense's lead researchers Nima Nikzad told attendees at the WLSA event in San Diego last week. A group of doctoral students including Nikzad from the University of California, San Diego's computer science and engineering department presented a paper on their findings using their system at the conference.

Their research showed that current air quality monitoring was insufficient and personal participatory sensing would enable a much more accurate picture. Nikzad, who represented the group, said the system can bridge the gap between personal sensing and regional measurement, by offering micro-level detail but at the regional level.

A user study, with 16 people who used different methods of transport but had at least a 20 minute commute daily, found that measurements varied significantly from those provided by official regional pollution monitoring stations. Applying geospatial statistical techniques enabled CitiSense to plot air quality data on a very detailed regional map and results from its early studies suggest personal sensing devices have an important role to play in the future.

Nikzad showed a detailed map of the UCSD campus where he lives and results which showed how air quality varied in different areas, depending on if it was a walkway or a bus terminus. The sensor reads air quality, transmits back to their servers which transmit the information to the user's smartphone.

"Since the EPA does not have enough sensors on the ground to capture this data, although we're not suggesting CitiSense be used for this purpose, something like this would help community leaders identify hotspots of pollution," Nikzad said.

In wrapping up, he admitted that one of the challenges will be keeping the sensors calibrated on the field, as will detecting and correcting faulty sensors. Energy would need to be better managed so the device does not drain some one's smart phone of battery power. CitiSense used a combination of equipment that cost $500 in total.

The opportunities are numerous, Nikzad said, and better understanding of exposure will lead to better understanding of disease etiology and revolutionize the practice of public health.