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.

imgp5647a

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.

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.

thyroid-cancer-incidence-figure-10

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

The Interphone study included 13 countries during the study period 2000 – 2004. The major results were published after a delay of 6 years in 2010. In a new publication 12 years after the study period, the intracranial distribution of glioma in relation to radiofrequency (RF) radiation from mobile phones was analyzed. Tumour localization for 792 regular mobile phone users was analyzed in relation to distance from preferred ear for mobile phone use.

In Table 2 five categories for the distance were used with > 115.01 mm as the reference category (α = 1.0).  An association with distance from preferred side of mobile phone use to center of tumour was found; the closer the distance the higher the risk. The highest risk was found in the group with the closest distance (0-55 mm) yielding α = 2.37, 95 % Confidence Interval (CI) = 1.56-4.56.

The same association was seen if distance was based on point with highest Specific Absorption Rate (SAR) instead of preferred ear and if using a model assuming that the preferred side of phone use was not exclusively used (“mixing proportion”). The latter model generated higher risk estimates than the other two but with wider confidence intervals.

In Table 3 tumour size, duration of phone use, cumulative phone use, cumulative number of calls were analyzed. Although not statistically significant, higher risks with decreasing distance were found in the upper levels of these dichotomized covariates.

α and 95 % CI in shortest distance group 0-55 mm from preferred ear to tumour center

Tumour size                        α                    95 % CI

≤18 cm3                              1.96               1.51 – 3.66

18 cm3                                4.09               1.90 – 12.0

Duration of phone use

<6 years                              2.02               1.31 – 4.28

≥6 years                              3.27               1.92 – 11.3

Cumulative phone use

<200 hours                          1.57                1.29 – 3.36

≥200 hours                          4.06                2.03 – 11.6

Cumulative number of calls

<4,000                                 1.55                  1.25 – 3.42

≥4,000                                 3.56                 2.05 – 9.88

The authors concluded that ‘Taken together, our results suggest that ever using a mobile phone regularly is associated with glioma localization in the sense that more gliomas occurred closer to the ear on the side of the head where the mobile phone was reported to have been used the most. However, this trend was not related to amount of mobile phone use, making it less likely that the association observed is caused by a relationship between mobile phone use and cancer risk.’

The first part although correct is misleading. The correct statement would be that the risk was highest for glioma closer to the ear as would be expected based on the exposure to RF radiation. The last sentence should have indicated that although not statistically significant, the risk was highest in the group with longest duration of phone use, highest cumulative phone use and number of calls. This is a pattern one would expect if there is an association between mobile phone use and glioma.

A similar tendency to not correctly downplaying the association is found in the abstract: ‘The association was independent of the cumulative call time and cumulative number of calls.’ Since many persons read only the abstract, as also presented in PubMed, correct presentation of the results including αs and 95 % CIs would have been more relevant.

The correct interpretation of this study is simply that it confirms an increased risk for glioma associated with mobile phone use.

 

Footnote: The α values represent the change in risk of observing a tumor within the given interval in comparison with the baseline intensity.