1. 59 Arnhall Drive, Westhill, Aberdeenshire, AB32 6TZ, UK
2. Health and Safety Executive, Harpur Hill, Buxton, SK17 9JN, UK
3. CNR-ISP and Universita Ca’ Foscari, Via Torino 155, 30123 Venezia, Italy
4. School of Public Health, University of West Attica, Leof Alexandras 196, 115 21 Athens, Greece
5. British Geological Survey, Keyworth, Nottingham, NG12 5GG, UK
6. Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK
7. Institut für Geowissenschaften, Johannes Gutenberg-Universität, Becher-Weg 21, 55099 Mainz, Germany