Within the European Environment and Health Action Plan an initiative to establish a coherent human biomonitoring approach in Europe was started. The project COPHES (COnsortium to Perform Human biomonitoring on a European Scale ) developed recommendations for a harmonized conduct of a human biomonitoring (HBM) survey which came into action as the pilot study DEMOCOPHES (DEMOnstration of a study to COordinate and Perform Human biomonitoring on a European Scale). Seventeen European countries conducted a survey with harmonized instruments for, inter alia, recruitment, fieldwork and sampling, in autumn/winter 2011/2012. Based on the countries' experiences of conducting the pilot study, following lessons learnt were compiled: the harmonized fieldwork instruments (basic questionnaire, urine and hair sampling) turned out to be very valuable for future HBM surveys on the European scale. A school approach was favoured by most of the countries to recruit school-aged children according to the established guidelines and country specific experiences. To avoid a low participation rate, intensive communication with the involved institutions and possible participants proved to be necessary. The communication material should also include information on exclusion criteria and offered incentives. Telephone contact to the participants the day before fieldwork during the survey can prevent the forgetting of appointments and first morning urine samples. To achieve comparable results on the European scale, training of interviewers in all issues of recruitment, fieldwork and sampling through information material and training sessions is crucial. A survey involving many European countries needs time for preparation and conduct. Materials for quality control prepared for all steps of recruitment, fieldwork and sampling proved to be important to warrant reliable results.

BiPRO GmbH Munich Germany

Centre de Recherche Public Gabriel Lippmann Belvaux Luxembourg

Environmental Health Centre Cluj Napoca Romania

Environmental Health Science International Hulst The Netherlands

Environmental Toxicology Centro Nacional de Sanidad Ambiental Madrid Spain

Federal Environment Agency Berlin Germany

Federal Office of Public Health Berne Switzerland

Federal Public Service Health Food Chain Safety and Environment Brussels Belgium

Flemish Institute for Technological Research Mol Belgium

Hainaut Vigilance Sanitaire Mons Belgium

Health Service Executive Environmental Health Department Leitrim Ireland

Institute for Prevention and Occupational Medicine of the German Social Accident Insurance Institute of the Ruhr University Bochum Bochum Germany

Institute of Environmental Medicine Karolinska Institutet Stockholm Sweden

Institute of Preventive Medicine Lisbon Faculty of Medicine Lisbon Portugal

Jožef Stefan Institute Ljubljana Slovenia

Laboratoire National de Santé Dudelange Luxembourg

Larnaca General Hospital Ministry of Health Larnaca Cyprus

National Environmental Health Office Health Service Executive Dublin Ireland

National Institute of Environmental Health Budapest Hungary

National Institute of Public Health Prague Czech Republic

National Institute of Public Health Prague Czech Republic and Charles University 3rd Faculty of Medicine Prague Czech Republic

Nofer Institute of Occupational Medicine Lodz Poland

Public Health Authority of the Slovak Republic Bratislava Slovakia

Public Health England Centre for Radiation Chemical and Environmental Hazards Oxfordshire United Kingdom

State General Laboratory Ministry of Health Nicosia Cyprus

University of Antwerp Belgium and Southern Denmark University Denmark and Flemish Institute for Technological Research Mol Belgium

University of Copenhagen Copenhagen Denmark

University of Leuven Leuven Belgium

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