Wireless phone use in childhood and adolescence and neuroepithelial brain tumours: Results from the international MOBI-Kids study.

In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. We cannot rule out, however, residual confounding from sources we did not measure. Overall, our study provides no evidence of a causal association between wireless phone use and brain tumours in young people. However, the sources of bias summarised above prevent us from ruling out a small increased risk.

Are primary school students exposed to higher noise levels than secondary school students in Germany?

BACKGROUND: Noise, one of the major environmental nuisances, affects the learning ability of children negatively. OBJECTIVE: With the assumption that in the existing German 4-type school system children are exposed to various noise levels in each type of school, we investigated the association between children's school type and environmental noise level. METHODS: In this cross-sectional study, we included 550 children, primary and secondary school students, aged 8-12 years, and who lived in 4 Bavarian cities. The environmental noise level was assessed by personal 24-h dosimeter measurements. The associations of interest were assessed by linear regression. RESULTS: The average day noise level of 80.0 dB(A) was relatively high, exceeding the threshold level of 60 dB(A). In the model adjusted for sex, socioeconomic status (SES), and place of residence, noise level was significantly higher for primary schools by almost 2.3 dB(A); however, after additional adjustments for age, this association was distorted. The mean night noise level of 43.7 dB(A) was not associated with the school level. We could not find any significant differences in the noise level between different types of secondary schools. CONCLUSION: We found evidence that in Germany, children, especially of a younger age from primary school, are exposed to high noise levels during day in and outside the school environment. School administration and parents should work to make schools less noisy and more accomplished for learning to achieve a bright future for the children.

[Objective assessment of total noise exposure over 24 hours: a cross-sectional study in Bavaria]. / Objektive Bestimmung der 24-Stunden-Gesamtlärmbelastung: eine Querschnittsstudie in Bayern.

INTRODUCTION: Noise can affect well-being and performance of individuals and might be associated with an increased risk of cardiovascular events. To date most epidemiological studies considered exposure from a single source of noise. The EU Environmental Noise Directive (2002/49/EC) requires a summative measurement of ambient noise. This study aimed to capture the participants' exposure to environmental noise by means of personal noise dosimetry. METHODS: Children (n=628, participation=61%, age 8-12 years), adolescents (n=632, participation=58%, age 13-17 years) and adults (n=482, participation=40%, age 18-65 years) were selected randomly from the population registry of 4 Bavarian towns and were invited to participate in a 24-h measurement using noise dosimetry. Noise exposures during day and night were analyzed separately. In addition, predictors of noise exposure were assessed. RESULTS: For daytime noise exposure mean±standard deviation were in children 80.0±5.8 dB(A), in adolescents 76.0±6.2 dB(A), in adults 72.1±6.1 dB(A) (p(ANOVA)<0.001). During the day personal noise exposure was statistically significantly higher for participants from smaller towns than for those living in Munich, while nighttime noise exposure was highest for participants from Munich [44.1±7.2 dB(A)]. CONCLUSION: The summative noise exposure in urban Bavaria is high, in particular among children at daytime. Increased exposure levels in children might be caused by themselves while, e.g., playing. Whether the higher daytime exposure in towns is due to high noise levels commuting between home and work has to be assessed in future studies.