Mahmoud Abdel-Salam is a member of the British Occupational Hygiene Society and is presently an assistant lecturer studying for his PhD in Environmental Sciences at the University of Bradford. Having completed a first degree in this area at Alexandria University in Egypt, his main interests are in the monitoring of air pollution in both the workplace and ambient environment.

Dr John Dennis is a full-time senior lecturer in the University of Bradfords Environmental Sciences department. His research interests, in which he also acts as an industrial consultant, include occupational and environmental pollution and human health issues. He also holds a number of patents in the field of aerosol science that are currently being developed for commercial application.