Background ionizing radiation
ISPM researchers found that children living in areas with higher levels of terrestrial and cosmic radiation tended to have a greater risk of developing leukaemia and brain tumours.
That ionising radiation increases cancer risks is well known from studies of people exposed to relatively high doses including atomic bomb survivors from Japan or patients receiving radiation therapy. But what about the more common low doses of radiation to which the population at large is exposed to such as natural background radiation or diagnostic radiology; do these also contribute to cancer risk and, if yes, do similar dose-response relationship apply?
A study by Ben Spycher, Claudia Kuehni and other researchers from the ISPM together with colleagues from Basel, Zürich and Lucerne was published in Environmental Health Perspectives in 2015 suggesting that the answer to the first of these questions is yes. The researchers included all children in the Swiss National Cohort aged less than 16 years – over 2 million children – and used a geographic radiation model to estimate levels of terrestrial and cosmic radiation at the children’s homes. Diagnoses of cancers were identified from the Swiss Childhood Cancer Registry. A two-fold higher risk for leukaemia and brain tumours was seen among children exposed to dose rates of ≥200 nSv/h (nano Sieverts per hour) compared to those exposed to <100 nSv/h. The researchers estimated that an increase in 1 mSv cumulative dose received since birth was associated with and 4% increase in risk both for leukaemia and brain tumours. However, statistical uncertainty was large and more large studies will be needed to establish reliable dose response relationships for low-dose ionising radiation.
Link to journal article: Background Ionizing Radiation and the Risk of Childhood Cancer: A Census-Based Nationwide Cohort Study
You can check other previous publications here:
Krebsrisiko bei Kindern durch Exposition gegenüber ionisierender Strahlung
Cancer chez les enfants dû à l’exposition aux rayonnements ionisants
Domestic Radon Exposure and Risk of Childhood Cancer: A Prospective Census-Based Cohort Study
Nuclear power plants
A large nationwide longitudinal study found no evidence of an increased risk of cancer in children born near nuclear power plants in Switzerland. The CANUPIS study was performed by the Institute of Social and Preventive Medicine (ISPM) at the University of Bern (Switzerland) in collaboration with the Swiss Childhood Cancer Registry and the Swiss Paediatric Oncology Group. Press release-Results of the CANUPIS study
Webpage of the study: Childhood Cancer and Nuclear Power Plants in Switzerland