A review of studies of childhood cancer and natural background radiation

Abstract

Purpose:The projected existence and magnitude of carcinogenic effects of ionising radiation at low doses and low dose rates is perhaps the most important issue in radiation protection today. Studies of childhood cancer and natural background radiation have the potential to throw direct light on this question, into a dose range below a few tens of mSv. This paper describes the studies that have been undertaken and their context, discusses some problems that arise and summarizes the present position.Conclusions: Many such studies have been undertaken, but most were too small to have a realistic chance of detecting the small effects expected from such low doses, based on risk projections from higher exposures. Case-control or cohort studies are to be preferred methodologically to ecological studies, but can be prone to problems of registration/participation bias.Interview-based studies of the requisite size would be prohibitively expensive and would undoubtedly also run into problems of participation bias.Register-based studies can be very large and are free of participation bias. However, they need to estimate the radiation exposure of study subjects using models rather than individual measurements in the homes of those concerned. At present no firm conclusions can be drawn from the studies that have been published to date. Further data and perhaps pooled studies offer a way forward.

Residential exposure to natural background radiation at birth and risk of childhood acute leukemia in France, 1990–2009

“…Our study has some limitations, with the main concern being NBR exposure modeling, in particular for radon concentration, a limitation our study shares with others (Kendall et al, 2021). Radon concentrations vary markedly even between neighboring houses, depending, in particular, on building materials and domestic habits, such as the frequency of ventilation (Demoury et al 2013).…”

“…The above findings were addressed at an international scientific workshop in 2018 and presented in a recent review with a focus on methodology, main study limitations, and possible sources of bias (Mazzei-Abba et al 2020). They were also discussed in a recent review by Kendall et al (Kendall et al 2021).…”

“…The first generation of epidemiological studies on NBR and childhood cancer suffered from marked limitations: the ecological studies considered NBR exposures averaged over large geographic areas (Henshaw et al 1990) or radon concentrations in drinking water as a proxy for radiation exposure (Collman et al 1991), while the case-control studies based on NBR measurements were limited by low participation rates. In addition, the small differences between case and control exposure levels, and the small expected effect of the exposure on childhood AL made the studies statistically underpowered (Kaletsch et al, 1999;Kendall et al, 2021;UKCCS, 2002aUKCCS, , 2002b.…”

Introduction to the Second Bill Morgan Memorial Special Issue: an update on low dose biology, epidemiology, its integration and implications for radiation protection

“…Part 2 was on "Epidemiology: Updates on epidemiological low dose studies", co-chaired by Cato M. Milder and Mark P. Little (Milder et al 2021). This second Bill Morgan Special Issue consists of two meeting reports (Laiakis et al 2021;Milder et al 2021), four review articles highlighted from recorded presentations in parts 1 and 2 (Chauhan et al 2021b;Kendall et al 2021;Little et al 2021;Paunesku et al 2021), three original articles (Chauhan et al 2021a;Golden et al 2021;Karpov et al 2021) and one review article (Preston et al 2021). give an overview of NCRP Report No.…”

“…In this Special Issue,Paunesku et al (2021) give an overview regarding cancer effects of low dose and low dose rate low linear energy transfer (low-LET) radiation in animal models Chauhan et al (2021a). report protein level changes in human lens epithelial cells exposed to X-rays at various dose rates Kendall et al (2021). give an overview of epidemiological studies on childhood cancer and natural background radiation Little et al (2021).…”