London, Feb 19 (IANS): Scientists have now turned smartphones into personal, real-time air pollution monitors.

Led by Mark J. Nieuwenhuijsen from the Centre for Research in Environmental Epidemiology (CREAL) in Barcelona, Spain, the team has used smartphone and sensing technology to better pinpoint where and when pollution is at its worst.

The researchers equipped more than 50 schoolchildren with smartphones that could track their location and physical activity.

The children also received sensors that continuously measured the ambient levels of black carbon - a component of soot.

Although most children spent less than four percent of their day travelling to and from school, commuting contributed to 13 percent of their total potential black carbon exposure.

"Many studies have investigated people's exposure to air pollution which is associated with respiratory and cardiovascular problems. But they usually create a picture of exposure based on air pollution levels outside people's homes," Nieuwenhuijsen said.

This approach ignores big differences in air quality in school and work environments.

"It also ignores spikes in pollution that happen over the course of the day such as during rush hour. So we wanted to test technology's ability to fill in these gaps," he noted.

The researchers concluded that mobile technologies could contribute valuable new insights into air pollution exposure.

The paper appeared in the journal Environmental Science & Technology.