The CityU research team (IMAGE) City University of Hong Kong Caption Professor Patrick Lee Kwan-Hon (right) in the School of Energy and Environment (SEE) at CityU, Miss Du Shicong (left), PhD student in SEE and the team collected samples from different types of man-made environments in Hong Kong for the research. Credit City University of Hong Kong Usage Restrictions Image must be used with appropriate caption and credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.