On 9 May 2014 a new French case-control study on mobile phone use and brain tumour risk in the CERENAT study was published online. It confirms an increased risk for gliomas in the heaviest users. Life-time cumulative use > 896 hours produced odds ratio (OR) = 2.89, 95 % confidence interval (CI) = 1.41-5.93. Number of calls (> 18 360 calls) gave OR = 2.10, 95 % CI = 1.03-4.31. Considering a 5-year latency period (5-year censorship) increased the risk further in the last decile of cumulative use to OR = 5.30, 95 % CI = 2.12-13.23.
Increased risk was found for analogue phone use; OR = 3.75, 95 % CI = 0.97-14.43, and digital mobile phone use only; OR = 2.71, 95 % CI = 1.03-7.10. Risks were higher for temporal tumours, occupational and urban mobile phone use. Unfortunately the study did not include use of cordless phones (DECT) which leads to underestimate of the risks since such use was regarded as no exposure to radiofrequency electromagnetic fields (RF-EMF).
The study included also cases with meningioma. A statistically significant increased risk was found for cumulative duration of calls > 896 hours yielding OR = 2.57, 95 % CI = 1.02-6.44. However, overall the results were less consistent for an association than for gliomas.
This study reports important findings that add to the conclusion that gliomas are caused by exposure to RF-EMF. It strengthens the conclusions in our article on causation using the Hill viewpoints on causation and association.