Lisbeth Knudsen received an MSc in Biochemistry in 1980 and PhD in Biomedicine 1993. Her present position is professor of experimental toxicology at the Department of Occupational and Environmental Health, The Institute of Public Health, University of Copenhagen. She was until 2009 a national member of the Scientific Advisory Committee (ESAC) for the European Centre for the validation of Alternative Methods (ECVAM) and is currently an active member of the EU Implementation Group on Biomonitoring. At the national level Lisbeth has coordinated several major biomonitoring studies within occupational health. She is the current Coordinator of the European Network on Children's Susceptibility and Exposure to Environmental Genotoxicants. She is an active participant in a number of EU-projects: COPHES (Consortium to Perform Human Biomonitoring on a European Scale), DEMOCOPHES (Demonstration of a Study to Coordinate and Perform Human Biomonitoring on a European Scale) and LIFE+ 09 ENV/BE00410. Lisbeth is also an active member of the Research Council of the Faculty of Health Sciences at the University of Copenhagen and the Danish Consensus Platform for 3R Alternatives to Animal Experimentation (DACOPA). In 2006 Lisbeth received the Nordic Alternative Price for promoting the development of alternatives to animal testing and she is the current coordinator of the Danish in vitro toxicology network and treasurer in the European Consensus Platform for 3R Alternatives to Animal Experimentation (ECOPA). Professor Domenico Franco Merlo received his Ph.D. in Environmental Health, Epidemiology from the University of Cincinnati, Ohio, USA in 1988. He is currently Director of the Unit of Epidemiology, Biostatistics and Clinical Trials, Department of Cancer Epidemiology and Prevention of the National Cancer Institute of Genoa, Italy. He coordinated and contributed to European and national studies on cancer risk associated with environmental and occupational exposure to crystalline silica, benzene, 2,3,7,8-TCDD, pesticides as well as studies including biomarkers of exposure, early biological effects, and individual susceptibility.