Incidence of childhood leukaemia before and after shut down of nuclear power plants in Germany in 2011: A population-based register study during 2004-2019
Menée à partir de données du registre allemand des cancers pédiatriques portant sur tous les enfants atteints d'une leucémie diagnostiquée entre 2004 et 2019, cette étude analyse l'évolution de l'incidence de la maladie chez les enfants vivant à proximité d'une centrale nucléaire où au moins un réacteur a été arrêté en 2011
The association between leukaemia and proximity to nuclear-power-plants (NPPs) has been assessed in several countries with inconsistent results. A case-control study from Germany had shown an increased risk for childhood leukaemia (diagnoses 1980-2003) near NPPs. Germany began shutting down nuclear reactors in 2011, following the Fukushima disaster. We tested whether the previously observed association between leukaemia and proximity to NPP persisted despite the shutdown. We used an ecological study design to investigate the incidence of leukaemia during 2004-2019 in children aged 0-14 years living near NPPs where at least one reactor was shut down in 2011. We defined study and control areas as municipalities whose surface area was at least 75% within 10 km or between 10 and 50 km of NPPs, respectively. We calculated age-standardised rates and incidence rate ratios (IRR) using control-areas as the reference. We also computed standardised incidence ratios (SIR) separately for each NPP using incidence rates of the German population as a reference. IRR decreased from 1.20 (95% confidence interval: 0.81-1.77) in 2004-2011 to 1.12 (0.75-1.68) in 2012-2019. Analyses of single plants showed an excess of childhood leukaemia during 2004-2019 for the Unterweser-NPP, based only on three cases, and the Krümmel-NPP (n=14; SIR: 1.98, 1.17-3.35]). We found slightly decreasing of leukaemia incidence rate ratios after the shutdown of nuclear reactors in 2011. Due to the small number of cases, risk estimates have large uncertainty. Further research including a longer follow-up is warranted. The consistent excess of incidence cases around Krümmel may require analytical epidemiological analysis.