Mobile phone use and risk of brain tumours: a systematic review of association between study quality, source of funding, and research outcomes

Over 20 years have passed since the initial spread of mobile phones in Japan. Epidemiological studies of mobile phone use are currently being conducted around the world, but scientific evidence is inconclusive. The present study aimed to simulate the incidence of malignant brain tumors in cohorts that began using mobile phones when they first became popular in Japan. Mobile phone ownership data were collected through an Internet‐based questionnaire survey of subjects born between 1960 and 1989. The proportion of mobile phone ownership between 1990 and 2012 was calculated by birth cohort (1960s, 1970s, and 1980s). Subsequently, using the ownership proportion, the incidence of malignant brain tumors was calculated under simulated risk conditions. When the relative risk was set to 1.4 for 1,640 h or more of cumulative mobile phone use and the mean daily call duration was 15 min, the incidence of malignant brain tumors in 2020 was 5.48 per 100,000 population for the 1960s birth cohort, 3.16 for the 1970s birth cohort, and 2.29 for the 1980s birth cohort. Under the modeled scenarios, an increase in the incidence of malignant brain tumors was shown to be observed around 2020. © 2019 Bioelectromagnetics Society

Section: Discussionmentioning

confidence: 99%

Simulation of the incidence of malignant brain tumors in birth cohorts that started using mobile phones when they first became popular in Japan

Sato

Kojimahara

Yamaguchi

2019

“…In addition, it has been reported that RF radiation may lead to cytotoxicity in hippocampal neuronal HT22 cells [Kim et al, ] and degenerative changes in hippocampus pyramidal cells [Hussein et al, ]. In a recent study, evidence was provided showing an association between mobile phone use and brain tumors, especially in people who used their mobile phones for more than 10 years [Prasad et al, ]. In another study, it was reported that long‐term use of mobile phones was linked to an increased risk of intracranial tumors [Bortkiewicz et al, ].…”

Section: Introductionmentioning

confidence: 99%

Effect of low‐level 1800 MHz radiofrequency radiation on the rat sciatic nerve and the protective role of paricalcitol

Çömelekoğlu

Aktaş

Demirbag

et al. 2018

The nervous system is an important target of radiofrequency (RF) radiation exposure since it is the excitable component that is potentially able to interact with electromagnetic fields. The present study was designed to investigate the effects of 1,800 MHz RF radiation and the protective role of paricalcitol on the rat sciatic nerve. Rats were divided into four groups as control, paricalcitol, RF, and RF þ paricalcitol. In RF groups, the rats were exposed to 1,800 MHz RF for 1 h per day for 4 weeks. Control and paricalcitol rats were kept under the same conditions without RF application. In paricalcitol groups, the rats were given 0.2 mg/kg/day paricalcitol, three times per week for 4 weeks. Amplitude and latency of nerve compound action potentials, catalase activities, malondialdehyde (MDA) levels, and ultrastructural changes of sciatic nerve were evaluated. In the RF group, a significant reduction in amplitude, prolongation in latency, an increase in the MDA level, and an increase in catalase activity and degeneration in the myelinated nerve fibers were observed. The electrophysiological and histological findings were consistent with neuropathy, and the neuropathic changes were partially ameliorated with paricalcitol administration. Bioelectromagnetics. 39:631-643, 2018.

“…The incidence of brain tumors is 7.0 per 100,000 population in the U.S. [Ostrom et al, 2015] and 2.4 per 100,000 population in Japan [Hori et al, 2015;National Cancer Center Japan, 2017]. Due to the low incidence of brain tumors, the case-control study design is often used in epidemiological studies on mobile phone use [Lagorio and R€ o€ osli, 2014;Prasad et al, 2017]. In case-control studies, the relationship between the side of mobile phone use and the side of brain tumors has been investigated.…”

Section: Introductionmentioning

confidence: 99%

Analysis of ear side of mobile phone use in the general population of Japan

Sato

Kojimahara

Taki

et al. 2017

This study aimed to clarify the distribution of the ear side of mobile phone use in the general population of Japan and clarify what factors are associated with the ear side of mobile phone use. Children at elementary and junior high schools (n = 2,518) and adults aged ≥20 years (n = 1,529) completed an Internet-based survey. Data were subjected to a logistic regression analysis. In children, due to the tendency to use the dominant hand, we analyzed the factors associated with the use of right ear in right-handed people. Statistically significant differences were observed only in talk time per call (odds ratio (OR) = 2.17; 95% confidence interval (CI): 1.22-3.99). In adults, due to the tendency to use the left ear, we analyzed factors associated with the use of left ear in right-handed people. Significant differences were observed in those aged 30-39 years (OR = 2.55; 95% CI: 1.79-3.68), those aged 40-49 years (OR = 3.08; 95% CI: 2.15-4.43), those aged >50 years (OR = 1.85; 95% CI: 1.20-2.85), and in those with a percentage of total talk time when using mobile phones at work of 51-100% (OR = 1.75; 95% CI: 1.21-2.55). We believe that future epidemiological studies on mobile phone use can be improved by considering the trends in mobile phone use identified in this study. Bioelectromagnetics. 39:53-59, 2018. © 2017 Wiley Periodicals, Inc.