Smog is a big problem in many of the world’s largest cities, especially in the massive urban agglomerations that pepper Asia. That’s why a group of researchers from Australia and China have developed a new method of detecting nitrogen dioxide in the air, which is a major contributor to smog in these cities, and causes some serious health issues. Using a new kind of sensor, smartphones could be transformed into portable air-scanners that can detect when there are unhealthy levels of nitrogen dioxide in the air. 

A new method to identify unhealthy levels of nitrogen dioxide could let those at risk take control of their health with cheap, personalised sensors, according to new research by Australian and Chinese scientists. Nitrogen dioxide contributes to the dangerous smog that lurks over many of the world’s cities, causing serious respiratory problems, among other health issues. Australian scientist Kourosh Kalantar-zadeh, a professor at RMIT’s Centre for Advanced Electronics and Sensors, told Mashable Australia he helped discover a new use for the material tin disulphide, which could be used as a sensor to read the level of nitrogen dioxide in the air. Kalantar-zadeh had a personal interest in finding a way to detect the gas after his pregnant wife was diagnosed with preeclampsia, a dangerous condition for mother and child associated with high blood pressure. Kalantar-zadeh realised nitrogen dioxide is considered by some scientists to be a risk factor in developing the illness. Around 80% of the nitrogen dioxide in our cities comes from vehicle exhaust, according to Australia’s Department of Environment, as well as other instances where fossil fuels are burnt, such from coal-fired power stations and petrol refineries.