Radon exposure and childhood cancers...3

A1 Inhalt - Contenu Perceptions de la population suisse concernant l'utilisation de matériel biologique pour la recherche biomédicale: résultats d'une étude CATI auprès de 1600 personnes en Suisse...2 Radon exposure and childhood cancers...3 Comparison of radiofrequency electromagnetic field exposure in five urban areas in the cities of Basel and Amsterdam...4 The effect of a smoking ban introduction on heart rate variability in Swiss hospitality workers...5 The association of breast milk constituents and duration of breast feeding with development of atopic disease in childhood...5

PERCEPTIONS DE LA POPULATION SUISSE CONCERNANT L'UTILISATION DE MATÉRIEL BIOLOGIQUE POUR LA RECHERCHE BIOMÉDICALE: RÉSULTATS D'UNE ÉTUDE CATI AUPRÈS DE 1600 PERSONNES EN SUISSE Daria Koutaissoff 1, Hans-Anton Lehr 2, Bernard Burnand 3, Brenda Spencer 3 1 IUMSP Lausanne, 2 Institut Universitaire de Pathologie, 3 IUMSP Background : La constitution de biobanques requiert un équilibre entre intérêts de la recherche et respect des droits des patients. Jusqu ici, peu d études ont été menées auprès de la population pour connaître les perceptions en matière d utilisation de matériel biologique. Méthode : Nous avons utilisé une «mixed method approach» (stratégie de recherche intégrant une approche qualitative et quantitative). L étude qualitative a permis de développer un questionnaire axé sur les enjeux en lien avec les préoccupations des acteurs. L étude quantitative, présentée ici, a été réalisée par téléphone auprès d un échantillon représentatif de l ensemble de la population suisse (1601 entretiens menés en 2010). Les principaux thèmes abordés concernaient les connaissances et attitudes vis-à-vis de la recherche, ainsi que l information et le consentement du patient. Résultats : Seulement un tiers (31%) des personnes interrogées s étaient demandées avant cette étude ce que l hôpital faisait avec les prélèvements. Lorsque la question leur est posée, la plupart des répondants (63%) pensaient que l hôpital se débarrasse des prélèvements. L attitude des répondants était positive vis-à-vis de la recherche : 50.5% souhaitaient que l hôpital conserve et utilise les prélèvements pour la recherche. Si une minorité (37%) souhaitait consentir à l utilisation de matériel biologique, l information paraissait cependant essentielle à la plupart des répondants (67%). La moitié des personnes interrogées (53.8%) souhaitaient également savoir comment leur échantillon a contribué à la recherche et une grande majorité (79%) étaient favorables à ce que l industrie pharmaceutique puisse bénéficier également de ce matériel pour développer de nouveaux médicaments. Conclusions : Peu de personnes ont réfléchi à cette thématique auparavant: il est difficile de mener un débat public dans un contexte où seule une minorité de personnes sont sensibilisées aux enjeux. Le besoin important d'être informé ne semble pas refléter une méfiance à l'égard de la recherche médicale mais correspondre à la volonté de plus de transparence et de partenariat avec les professionnels de la santé. 2

RADON EXPOSURE AND CHILDHOOD CANCERS Dimitri Hauri 1, Anke Huss 2, Frank Zimmermann 3, Michael Grotzer 4, Nicolas von der Weid 5, Claudia E. Kuehni 6, Martin Röösli 1 1 Swiss Tropical and Public Health Institute, Basel. University of Basel, Basel, 2 Institut for Risk Assessment Sciences, University of Utrecht, The Netherlands, 3 Institut für Radioonkologie, Universitätsspital Basel, Basel, 4 Neuro- Onkologie, Kinderspital Zürich, Zürich, 5 Service de pédiatrie, Centre hospitalier universitaire vaudois (CHUV), Lausanne, 6 Institut für Sozial- und Präventivmedizin (ISPM), Bern Background and Aims: The effect of indoor radon exposure on childhood malignancies is unknown. In Switzerland, average radon exposure is relatively high due to the geology and is the major contributor to total effective ionizing radiation dose. The World Health Organization (WHO) recommends constructional action if 100 Bq/m³ is exceeded. This is the case in 35% of all apartments in Switzerland according to our nationwide exposure assessment model. By means of a nationwide cohort study we aimed at investigating whether indoor radon concentration increases the risk of childhood cancer in general and of leukaemia and central nervous system (CNS) tumours in particular. Methods: A prospective census-based cohort design was applied to investigate the potential association between radon exposure and childhood malignancies. All children aged between 0 and 15 years, born before the December 4 th, 2000 (date of census) and resident in Switzerland were included in the cohort. The follow-up period lasted from the date of census until death, emigration, reaching the age of 16 or December 31 st, 2008. Radon exposure was assessed for each child based on a nationwide radon prediction model that was a log linear regression model. The association between radon exposure and childhood malignancies was analyzed using Cox regression models adjusted for environmental radiation exposure from external sources (cosmic, terrestrial and artificial ground radiation), gender, birth order within each household, socio-economic status of the parents and other potential confounders. Results: The mean radon concentration in the 1,300,000 children included in the analysis was 98.4 Bq/m³, ranging from 21.0 to 552.3 Bq/m³ (arithmetic mean). 772 children were diagnosed with childhood malignancies of which 228 had leukaemia and 205 CNS tumours. Cox regression analyses did not indicate an association between residential radon exposures and all childhood cancer incidences, leukaemia or brain tumours. Conclusion: Unlike several previous ecological and case-control studies, our preliminary results do not indicate associations between residential radon with the risk to develop malignancies, leukaemia and brain tumour during infancy. Radon decay results in alpha particles displaying small effective doses on the red bone marrow. Thus, absence of association is plausible from a biophysical point of view. 3

COMPARISON OF RADIOFREQUENCY ELECTROMAGNETIC FIELD EXPOSURE IN FIVE URBAN AREAS IN THE CITIES OF BASEL AND AMSTERDAM Damiano Urbinello 1, Anke Huss 2, Johan Beekhuizen 2, Roel Vermeulen 2, Martin Röösli 1 1 Swiss Tropical and Public Health Institute (Swiss TPH), 2 Institute for Risk Assessment Sciences, Utrecht University Introduction: Switzerland has implemented precautionary regulatory limits for radiofrequency electromagnetic field (RF-EMF) exposure from mobile phone base stations. As a consequence, regulatory limits are lower than in the Netherlands. It is unknown whether lower regulatory limits results in lower population exposure. The aim of this study was to compare area profiles in different matched urban environments in the cities of Basel and Amsterdam in order to characterize RF-EMF exposure of the population. Methods: Twelve frequency bands ranging from FM (Frequency Modulation, 88 MHz) to W- LAN (Wireless Local Area Network, 2.5 GHz) were measured using a portable measurement device. Data collection took place between November 2010 and January 2012 each second week on two consecutive days simultaneously in both cities. Data collection procedure in both cities was based on a standardized measurement protocol. We differentiated between four types of area: central and decentral residential areas, downtown and business area. Results: The electrical field strength of all mobile phone base station frequency bands (GSM 900, GSM 1800 and UMTS) combined, averaged over all areas revealed a higher RF-EMF exposure in Amsterdam (0.42 Vm -1 ) than in Basel (0.24 Vm -1 ). Within cities, highest values occurred in downtown and business areas (0.3 Vm -1 ) of Basel as well as in Amsterdam (0.52 and 0.48 Vm -1 ). In contrast, lowest values were measured in a decentral residential area of Basel (0.09 Vm -1 ), and in the central residential area of Amsterdam (0.31 Vm -1 ). Overall, GSM 900 and GSM 1800 frequencies had a higher contribution to total exposure from mobile phone base stations than UMTS signals. Conclusions: Standardized data collection enables a direct comparison within and between cities. Our study provides evidence that a standardized microenvironmental repetitive data collection survey over a short time period is feasible and data are enough robust to capture differences in RF-EMF exposure between cities and microenvironments. We observed that exposure contribution in outdoor areas arises mainly from mobile phone base stations, particularly in areas as downtown or business venues with a higher density of base stations and microcells. Exposure levels were consistently higher in Amsterdam than in Switzerland, although areas with similar characteristics were compared. Possibly, precautionary exposure limits in Switzerland results in a lower RF-EMF exposure in the everyday environment. 4

THE EFFECT OF A SMOKING BAN INTRODUCTION ON HEART RATE VARIABILITY IN SWISS HOSPITALITY WORKERS Sarah Rajkumar 1, Cong Khanh Huynh 2, Georg Bauer 3, Martin Röösli 1 1 Swiss TPH, Basel, 2 Institute for Work and Health, Lausanne, 3 Institute of Social and Preventive Medicine, University of Zürich and Center for Organizational and Occupational Sciences, ETH Zurich Background and Aims: In May 2010 Switzerland introduced a nationwide but heterogeneous smoking ban in the hospitality sector. To evaluate the impact of the ban, personal environmental smoke exposure (ETS) exposure and cardio respiratory health status of 92 nonsmoking hospitality workers were measured in a longitudinal study before the new law was implemented, as well as 6 and 12 months after. Methods: At each examination, heart rate variability (HRV) data was collected by means of a 10 minute ECG with participants at rest in supine position. SDNN (standard deviation of all NN intervals) and RMSSD (square root of the mean squared difference of successive NNs) were calculated as an indicator for HRV. Further data were gathered using paper questionnaires and computer-based interviews. Exposure to ETS was measured using a passive sampler that determines the number of passively smoked cigarettes. Personal ETS exposure was obtained from a time-weighted average of the badge placed at the work place. The intervention group underwent a change in smoke exposure, while control group members never had been, or remained, exposed to ETS at work. Change of heart rate variability after smoking ban introduction was separately analysed in both groups using a multilevel model adjusted for age, sex, BMI, and hypertension. In the full multilevel model the association between SDNN and measured ETS exposure was analysed in the whole dataset. Results: Average time-weighted ETS exposure decreased from 2.6 (95%-CI: 1.7-3.4) cigarette equivalents/day at baseline to 0.2 (95%-CI: 0.1-0.2) cigarette equivalents/day at both followups. Between baseline and 2 nd follow-up SDNN increased significantly by 17% (p=0.002) and RMSSD by 17% (p=0.005) (n=55). In the control group SDNN decreased by 19% (p=0.13) and RMSSD by 12% (p=0.47) (n=33). According to the full multilevel model each decrease of ETS exposure by one cigarette equivalent results in a SDNN increase of 2% (p=0.08) and a RMSSD increase by 2% (p=0.02) Conclusions: Twelve months after introducing the smoking ban average heart rate variability significantly improved in the intervention group while staying the same in the control group. The observed changes were related to the extent of measured ETS exposure. This study provides evidence that a smoking ban introduction improves the cardiovascular health of bar and restaurant workers. THE ASSOCIATION OF BREAST MILK CONSTITUENTS AND DURATION OF BREAST FEEDING WITH DEVELOPMENT OF ATOPIC DISEASE IN CHILDHOOD Georg Loss 1, Laura Orivuori 2, Juha Pekkanen 3, Erika von Mutius 4, Gert Doekes 5, Outi Vaarala 2, Charlotte Braun- Fahrländer 1 1 Swiss Tropical and Public Health Institute, Basel and University of Basel, Switzerland, 2 National Institute for Health and Welfare, Department of Vaccination and Immune Protection Helsinki, Finland, 3 National Institute for Health and Welfare, Department of Environmental Health and University of Eastern Finland, Public Health and Clinical Nutrition, Kuopio, Finland, 4 LMU Munich, University Children s Hospital, Munich, Germany, 5 Utrecht University, Institute for Risk Assessment Sciences (IRAS), Division of Environmental Epidemiology, Utrecht, The Netherlands 5

Background: Breast milk contains anti-microbial and anti-inflammatory agents, which protect the child from infections and educate its immune system. Our aim was to examine whether the levels of total immunoglobulin A (IgA) and transforming growth factor-β1 (TGF-β1) in breast milk and the duration of breast feeding were associated with the child's risk for atopic disease. Methods: The PASTURE cohort study population comprised families living in rural areas of Finland, France, Germany and Switzerland. Questionnaires were administered during pregnancy and then yearly up to age 6 to collect data on environmental factors and health outcomes. Asthma at age 6 and cumulative atopic dermatitis (AD) at age 2 and 4 were defined by doctors diagnosis ever in life. Atopy was defined by specific IgE levels in blood samples collected at age 1, 4 and 6. A weekly diary kept from month 3 to 12 provided detailed information on breast feeding behaviour. Two months postpartum, 629 breast milk samples were collected and TGF-β1 and IgA were measured using the ELISA method. Breast milk constituents and breast feeding behavior were related to health outcomes using multivariate logistic regression models. Results: TGF-β1 and IgA levels in breast milk taken at month 2 were lower for mothers who reported longer breast feeding durations (p for linear trend <0.001). IgA levels in breast milk were inversely associated with cumulative atopic dermatitis at age 2 indicative of a dose response relationship (p for linear trend: p = 0.013) and at age 4. These associations were only significant among mothers breast feeding for more than 6 months suggesting an effect modification by duration of breast feeding. TGF-β1 levels showed no effect on AD but longer breast feeding duration was inversely associated with the risk for late onset AD (after age 2). Results for the associations of TGF-β1 and IgA levels in breast milk with atopy and asthma were inconclusive. Conclusions: Our findings indicate that IgA levels in breast milk reduce the risk to develop of atopic dermatitis in early life while TGF-β1 levels showed no consistent associations with atopic diseases. 6