Increasing brain tumor rates in Sweden

Recently we published a new article on brain tumor rates in Sweden using the Inpatient Register for the time period 1998-2015. Also incidence data using the Swedish Cancer Register were analyzed for the same time period. The full article can be found here, see also abstract below.

We used the Swedish Inpatient Register (IPR) to analyze rates of brain tumors of unknown type (D43) during 1998-2015. Average Annual Percentage Change (AAPC) per 100,000 increased with +2.06%, 95% confidence interval (CI) +1.27, +2.86% in both genders combined. A joinpoint was found in 2007 with Annual Percentage Change (APC) 1998-2007 of +0.16%, 95% CI -0.94, +1.28%, and 2007-2015 of +4.24%, 95% CI +2.87, +5.63%. Highest AAPC was found in the age group 20-39 years. In the Swedish Cancer Register the age-standardized incidence rate per 100,000 increased for brain tumors, ICD-code 193.0, during 1998-2015 with AAPC in men +0.49%, 95% CI +0.05, +0.94%, and in women +0.33%, 95% CI -0.29, +0.45%. The cases with brain tumor of unknown type lack morphological examination. Brain tumor diagnosis was based on cytology/histopathology in 83% for men and in 87% for women in 1980 in the Cancer Register. This frequency increased to 90% in men and 88% in women in 2015. During the same time period CT and MRI imaging techniques were introduced and morphology is not always necessary for diagnosis. If all brain tumors based on clinical diagnosis with CT or MRI had been reported to the Cancer Register the frequency of diagnoses based on cytology/histology would have decreased in the register. The results indicate underreporting of brain tumor cases to the Cancer Register. The real incidence would be higher. Thus, incidence trends based on the Cancer Register should be used with caution. Use of wireless phones should be considered in relation to the change of incidence rates.


High radiofrequency radiation at the Stockholm Central Station in Sweden

We measured the radiofrequency (RF) radiation at the Stockholm Central Station in Sweden in November 2015. The full study can be read here. The exposimeter EME Spy 200 was used and it covers 20 different RF bands from 88 to 5,850 MHz. In total 1,669 data points were recorded. The median value for total exposure was 921 µW/m2 (or 0.092 μW/cm2; 1 μW/m2=0.0001 μW/cm2) with some outliers over 95,544 µW/m2 (6 V/m, upper detection limit). The mean total RF radiation level varied between 2,817 to 4,891 µW/m2 for each walking round.

Hot spots were identified, for example close to a wall mounted base station yielding over 95,544 µW/m2 and thus exceeding the exposimeter’s detection limit, see Figure below. A man is standing with his smartphone just a couple of meters below a base station (see arrow). In that area maximum measured power density in the GSM +UMTS 900 downlink band from the base station was 95,544 µW/m2, which is the upper limit of measurement for EME Spy 200.


Almost all of the total measured levels were above the precautionary target level of 3 to 6 µW/m2 as proposed by the BioInitiative Working Group in 2012. That target level was one-tenth of the scientific benchmark providing a safety margin either for children, or chronic exposure conditions. Considering the rapid progress of this technology, including 5G that is to be launched in the near future, it is important to monitor current RF radiation exposure in the environment.

WHO Monograph on Radiofrequency Radiation and ICNIRP

There is growing international concern on the biased representation of persons in the preparation of the WHO Monograph on Radiofrequency Radiation. As discussed earlier the group is dominated by members of ICNIRP. In fact the Ethical Board at the Karolinska Institute in Stockholm, Sweden concluded already in 2008 that being a member of ICNIRP may be a conflict of interest that should be stated in scientific publications (Karolinska Institute Diary Number 3753-2008-609).

A recent letter to WHO written by members of the BioInitiative Working Group describes the unbalanced ‘no-risk’ group at WHO preparing the document. The full text may be read here.

More results from Interphone confirm glioma risk associated with use of mobile phones

The Interphone study on use of mobile phones and brain tumour risk included 13 countries during the study period 2000 – 2004. The major results were published after a delay of 6 years in 2010. In the last decile of cumulative exposure > 1,640 h a statistically significant increased risk for glioma was found, OR = 1.40, 95 % CI =1.03-1.89. In the other categories of cumulative use a decreased risk was found. Bias and confounding were discussed as potential reasons for that. Analysing only subjects with regular use of a mobile phone yielded OR = 1.82, 95 % CI = 1.15-2.89 in the group with highest cumulative use.

There was an age difference between cases and controls in the Interphone study and furthermore cases and the matched controls were interviewed at different time periods, controls usually later than cases. This is problematic for mobile phone use with rapid penetration of the use in the population. In a recently published alternative analysis, cases and controls nearest in age and time for interview were included. The association between mobile phone use and glioma was strengthened thereby. Thus, among regular users in the 10th decile (> 1,640 h) cumulative use gave OR = 2.82, 95 % CI = 1.09-7.32. The authors concluded that there was ‘stronger positive association among long-term users and those in the highest categories of cumulative call time and number of calls.’.

Since the IARC evaluation in 2011 on exposure to radiofrequency radiation form mobile phones, and other devices that emit such radiation, and brain tumour risk additional research has strengthened the association. It is by now time to re-evaluate the scientific evidence on the cancer risk from radiofrequency radiation.

Increasing incidence of thyroid cancer in the Nordic countries

The incidence of thyroid cancer is increasing in many countries, especially the papillary type that is the most radiosensitive type. We used the Swedish Cancer Register and NORDCAN to study the incidence of thyroid cancer during 1970-2013 using joinpoint regression analysis. The incidence increased during the whole study period in both men and women. Based on NORDCAN data, there was a statistically significant increase in the incidence of thyroid cancer in the Nordic countries during the same time period. In both women and men one joinpoint was detected in 2006. The incidence increased substantially during 2006-2013 in women; annual percentage change (APC) +6.16 % (95 % CI +3.94, +8.42 %) and in men; APC +6.84 % (95 % CI +3.69, +10.08 %). These results were similar as in the Swedish Cancer Register. Analyses based on data from the Cancer Register showed that the increasing trend in Sweden was mainly caused by thyroid cancer of the papillary type. We postulate that the whole increase cannot be attributed to better diagnostic procedures. Increasing exposure to ionizing radiation, e.g. medical CT scans, and to radiofrequency radiation (non-ionizing radiation) should be further studied as causative factors to this emerging thyroid cancer health problem.

One aspect to be studied is the increasing use of mobile phones. The antenna was previously placed at the top of the phone but is usually now placed at the bottom in smartphones. This gives higher exposure of radiofrequency radiation to the thyroid gland, see figure. A smartphone can in addition have multiple antennas.


Portable Screen-Based Media Devices and Sleep

In a new report analysis was made of studies on use of e.g. mobile phones and tablets and sleep and tiredness. The report included analysis of 20 cross-sectional studies of children and adolescents aged 6-19 years, in total more than 125,000 subjects. Use of media devices during bedtime gave about doubled risk for inadequate sleep, poor sleep and tiredness daytime. Also if these devices were not actively used an increased risk, although lower, was found for these health problems.

In USA 72 % of children and 89 % of adolescents have access to at least one media device. Most of them use it during bedtime.

Various pathways were discussed for the negative sleep impact: “First, they may negatively influence sleep by directly displacing, delaying, or interrupting sleep time. Second, the content can be psychologically stimulating, and, third, the light emitted from devices affects circadian timing, physiological sleep, and alertness.”

It is remarkable that the authors do not discuss exposure to radiofrequency (RF) fields (electromagnetic radiation) as a contributing factor. Wireless devices such as mobile phones (smartphones) emit RF radiation also when they are not used; updating apps, internet, SMS etc. This passive exposure may have contributed to the sleep disturbances in persons that did not actively use them. The authors seem to have been unwilling to discuss RF radiation. In fact studies on electromagnetic radiation were excluded. Also wireless use of desktops and computers would have been of interest. The authors stated:

“The exclusion criteria were studies of stationary exposures, such as televisions or desktop or personal computers, or studies investigating electromagnetic radiation.”