Interphone Canada redovisar fördubblad risk för hjärntumör (gliom) för användning av mobiltelefon

Resultat för hela Interphone publicerades 2010. För gruppen med högst sammanlagd användning av mobiltelefon, 1640 timmar eller mer påvisades statistiskt säkerställd riskökning för gliom, oddskvot 1,40 (95% konfidensintervall 1,03–1,89).  Detta motsvarar mindre än en halv timme om dagen under 10 år (27 minuter).

I Interphone ingick 13 länder och trots att avsikten var att alla länder skall redovisa sina resultat separat så har det inte blivit fallet. Kanada har nu redovisat sina resultat. Totalt ingick 170 fall med gliom (svarsfrekvens 63 %) och 653 kontrollpersoner (svarsfrekvens 56 %).  Dessutom ingick endast 94 fall med meningiom, 57 fall med spottkörteltumör och 84 fall med tumör på hörselnerven (acusticusneurinom). För kumulativ användning av mobiltelefon 558 timmar eller mer sågs fördubblad risk för gliom, oddskvot 2,0 (95 % konfidensintervall 1,2 – 3,4). Risken ökade något till oddskvot 2,2 (95 % konfidensintervall 1,3 – 4,1) om man justerade för metodfel (minnesfel, selektionsfel på grund av lågt deltagande). Risken är alltså högre än för hela Interphone. Användning av mobiltelefon 558 timmar motsvarar mindre än 10 min om dagen under 10 år.

Studien bekräftar alltså vår slutsats att trådlösa telefoner ökar risken för gliom, se Carlberg, Hardell 2017.

Annons

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Brev till WHO om radiofrekventa fält och risken för hjärntumörer

Det första utkastet till monografi om hälsoeffekter av radiofrekventa fält från WHO innehåller många sakfel som vi påpekat tidigare. Vi har nu påtalat detta på nytt och skickat till WHO brev enligt nedan. IARC har fått samma brev med begäran om ny utvärdering av cancerrisker.

 

 

World Health Organization                                                              4 August, 2015

 

Dr Margaret Chan, Director General

World Health Organization

Avenue Appia 20, 1211 Geneva 27

Geneva, Switzerland

 

Emelie van Deventer, Team Leader

Radiation Programme Department of Public Health,

Environmental and Social Determinants of Health,

World Health Organization

Geneva, Switzerland

 

Dear Ms. Margaret Chan

Dear Ms. Emelie van Deventer

 

Further Comments on the WHO draft: Radio Frequency fields: Environmental Health Criteria Monograph

On 15 December, 2014 we submitted comments on the WHO draft on radio frequency fields and health. Since we have not got a satisfactory reply from WHO, not seen a revision of the draft, and adding to that more published studies that reinforce the increased risk for certain brain tumours associated with use of wireless phones we want to submit the following, additional comments.

The brain is the primary target organ for exposure to radiofrequency electromagnetic fields (RF-EMF) during the use of the handheld wireless phone. This has given concern of an increased risk for brain tumours. The carcinogenic effect of RF-EMF on humans was evaluated at a meeting during 24 – 31 May 2011 at the International Agency for Research on Cancer (IARC) at WHO in Lyon, France. One of us (LH) was part of the expert group. The Working Group categorised RF-EMF from mobile phones, and from other devices that emit similar non-ionising electromagnetic fields in the frequency range 30 kHz–300 GHz, as a Group 2B, i.e. a possible, human carcinogen (http://monographs.iarc.fr/ENG/Monographs/vol102/mono102.pdf).

Since then more studies have been published that strengthen the association between use of wireless phones (mobile and cordless phones) and increased risk for brain tumours. We have performed long-term research in this area and in the following we give a short up-dated summary of our findings based on research since the 1990’s. In our publications relevant information can be found also on other studies, as well as discussions of the current scientific evidence.

Glioma:

Glioma is a malignant brain tumour (“brain cancer”), and the most common type is glioblastoma multiforme with a poor prognosis. We have published a statistically significant increased risk for glioma among users of both mobile and cordless phones. The risk increased with latency (time from first use of the phone until tumour diagnosis) and cumulative number of hours for use. Highest risk was found in the area of the brain with highest exposure to RF-EMF. All these results are of biological relevance; that is what would be expected for a causal association. The full paper can be read here:

http://www.pathophysiologyjournal.com/article/S0928-4680(14)00064-9/pdf

Meningioma:

Menigioma is mostly a benign brain tumour and accounts for about 30 % of all intracranial tumours. The incidence is approximately 2-times higher in women than in men. No conclusive evidence of an association between use of mobile and cordless phones and meningioma was found in our study. However, taking the long latency periods that have been reported for the increased meningioma risk associated with exposure to ionizing radiation it is still too early to make a definitive risk assessment. Results for even longer latency periods of wireless phone use than in our study are desirable, see more details here:

http://www.spandidos-publications.com/or/33/6/3093

Acoustic neuroma:

Acoustic neuroma or Vestibular Schwannoma is a rare benign tumour in the eighth cranial nerve that leads from the inner ear to the brain. It grows slowly and does not undergo malignant transformation, but may give compression of vital brain stem centres. Tinnitus and hearing problems are usual first symptoms of acoustic neuroma. We published a clear, statistically significant, association between use of mobile and cordless phones and acoustic neuroma. The risk increased with time since first use. For use of both mobile and cordless phones the risk was highest in the longest latency group. Tumour volume increased per 100 hours of cumulative use and year of latency for wireless phones indicating tumour progression from RF-EMF. The whole study can be read here:

http://www.spandidos-publications.com/ijo/43/4/1036

Brain tumour prognosis:

A causal association would be strengthened if use of wireless phones has an impact on the survival of glioma patients. We analyzed survival of 1,678 glioma patients in our case-control studies 1997-2003 and 2007-2009. Use of wireless phones in the > 20 years latency group (time since first use) yielded increased hazard ratio (HR) = 1.7, 95 % confidence interval (CI) = 1.2-2.3 for glioma, i.e. decreased survival. Increased HR was found for use of both mobile and cordless phones. Highest HR was found for cases with first use before the age of 20 years. These results strengthen a causal association between use of wireless phones and glioma. The publication can be read here:

http://www.mdpi.com/1660-4601/11/10/10790

Risk in different age groups of first use:

In our glioma study we found highest risk for subjects with first use of mobile or cordless phone before the age of 20, see Table 8 in the publication:

http://www.pathophysiologyjournal.com/article/S0928-4680(14)00064-9/pdf

We published similar results for acoustic neuroma and use of mobile phones, see Table 21.2:

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.433.7480&rep=rep1&type=pdf

Children and adolescents are more exposed to RF-EMF than adults due to thinner skull bone, higher conductivity in the brain tissue, and a smaller head. The developing brain is also more vulnerable than in adults and it is still developing until about 20 years of age. The finding of higher risk in young persons is worrying, not the least due to the high prevalence of use of wireless phones in children and adolescents.

Brain tumour incidence:

It is not correct to claim that the incidence of brain tumours has not increased in the Scandinavian countries. The age-standardized incidence of brain tumours increased dramatically in Denmark with +41.2 % among men and +46.1 % among women during 2003-2012 (http://www.ssi.dk/Aktuelt/Nyheder/2013/~/media/Indhold/DK – dansk/Sundhedsdata og it/NSF/Registre/Cancerregisteret/Cancerregisteret 2012.ashx).

Due to the well-known under-reporting of brain tumours to the Swedish Cancer Registry we studied brain tumour rates using the Swedish National Inpatient Register and the Causes of Death Register (see http://www.mdpi.com/1660-4601/12/4/3793/htm ). In summary we found a statistically significant increasing rate of not specified brain tumours from 2007 in the Inpatient Register and from 2008 in the Causes of Death Register. Our study indicated that several of these tumours were never reported to the Swedish Cancer Register. The results are in accordance with a reasonable latency period for use of wireless phones, e.g. mobile phones, see Figures 5 and 6 in our publication. Thus, the Swedish Cancer Register data cannot be used to dismiss an increased risk for brain tumours associated with use of wireless phones. On the contrary our study is consistent with an association considering a reasonable tumour induction period.

Mechanistic aspects:

– Reactive oxygen species:

RF-EMFs do not cause direct DNA damage. On the other hand numerous studies have shown generation of reactive oxygen species (ROS) that can cause oxidative damage of DNA. This is a well-known mechanism in carcinogenesis for many agents. The broad biological potential of ROS and other free radicals makes radiofrequency radiation a potentially hazardous factor for human health, not only cancer risk but also other health effects. A recent update can be read here:

http://informahealthcare.com/doi/abs/10.3109/15368378.2015.1043557

-Tumour promotion:

Tumour promotion by RF-EMF exposure was reported in 2010 in a study on mice: http://www.ncbi.nlm.nih.gov/pubmed/20545575. These findings were recently replicated and add to the relevance of tumour risk: http://www.ncbi.nlm.nih.gov/pubmed/25749340

-p53:

The p53 protein is a transcription factor that plays a vital role in regulating cell growth, DNA repair and apoptosis, and p53 mutations are involved in disease progression. In a recent study it was found that use of mobile phones for ≥3 hours a day was associated with increased risk for the mutant type of p53 gene expression in the peripheral zone of astrocytoma grade IV (glioblastoma multiforme), and that this increase was statistically significant correlated with shorter overall survival time:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4178273/

 These results are in agreement with the decreased survival for patients with astrocytoma grade IV (glioblastoma multiforme) associated with long-term use of mobile phones and cordless phones that we reported in 2014, see above the section on prognosis.

Causality:

To further evaluate strengths of evidence Sir Austin Bradford Hill wrote in the 1960’s a famous article on association or causation at the height of the tobacco and lung cancer controversy: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1898525/pdf/procrsmed00196-0010.pdf

Hill offered a list of nine aspects of an association to be considered when deciding if an association is causal. However, he did not request all nine viewpoints to be fulfilled for causality. We used the Hill criteria to evaluate the causality on brain tumour risk from RF-EMF emitted from wireless phones. We concluded that based on the Hill criteria, glioma and acoustic neuroma should be considered to be caused by RF-EMF emissions from wireless phones and regarded as carcinogenic to humans, classifying it as Group 1 according to the IARC classification. See more here:

http://www.degruyter.com/view/j/reveh.2013.28.issue-2-3/reveh-2013-0006/reveh-2013-0006.xml

Conclusion:

Our results are in agreement with other studies such as the international Interphone study and the French CERENAT study. This is discussed in more detail in e.g. our article on glioma risk, see also:

http://www.pathophysiologyjournal.com/article/S0928-4680(12)00110-1/pdf

The so called Danish cohort study on mobile phone users has been taken as evidence of no risk. However, the many shortcomings as reviewed elsewhere makes the study inconclusive regarding assessment of cancer risk. It should not be cited as evidence of no risk, for more details see: http://www.degruyter.com/view/j/reveh.2012.27.issue-1/reveh-2012-0004/reveh-2012-0004.xml?format=INT

In summary there is consistent evidence of increased risk for glioma and acoustic neuroma associated with use of mobile phones and cordless phones. Furthermore, the risk is highest for persons with first use before the age of 20, which is of special concern. Our conclusion is that RF-EMF should be regarded as a human carcinogen. The IARC classification should be updated to at least Group 2A, a probable human carcinogen. Current guidelines for exposure need to be urgently revised. The WHO Monograph draft on this issue is based on selective inclusion of studies and wrong assessment of the evidence of increased risk. Thus the Danish cohort study on mobile phone users and the Swedish Cancer Register data cannot be used as evidence of no increased risk. It is important that the public and decision makers are given correct information about the cancer risk so that they can make decisions based on correct data and take precautions. Otherwise there is an obvious risk of forthcoming increasing impairment of human health and increasing numbers of cancer in the population. We anticipate correction of the Monograph and your reply to this letter no later than 15 September, 2015. If you so wish our research group may of course give a presentation at WHO on this topic.

Yours sincerely,

 

Lennart Hardell, MD, PhD

Department of Oncology

University Hospital

SE-701 85 Örebro

Sweden

 

Michael Carlberg, MSc

Department of Oncology

University Hospital

SE-701 85 Örebro

Sweden

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Brev till New York Times

Ms. Margaret Sullivan, Public Editor                                       July 24, 2015

Ms. Carol Pogas, Reporter

 

The New York Times

Regarding: Cellphone Ordinance Puts Berkeley at Forefront of Radiation Debate http://www.nytimes.com/2015/07/22/us/cellphone-ordinance-puts-berkeley-at-forefront-of-radiation-debate.html?_r=0

Published online July 21, 2015

Dear Ms. Sullivan and Ms. Pogas,

We have read this article in the New York Times with interest. However, there are several mistakes, and even wrong statements, on the health hazards from exposure to radiofrequency electromagnetic fields (RF-EMF) from cell phones in the article. In the following we want to correct some of the false statements.

The brain is the primary target organ for exposure to RF-EMF during the use of the handheld wireless phone. This has given concern of an increased risk for brain tumours. The carcinogenic effect of RF-EMF on humans was evaluated at a meeting during 24 – 31 May 2011 at the International Agency for Research on Cancer (IARC) at WHO in Lyon, France. One of us (LH) was part of the expert group. The Working Group categorised RF-EMF from mobile phones, and from other devices that emit similar non-ionising electromagnetic fields in the frequency range 30 kHz–300 GHz, as a Group 2B, i.e. a possible, human carcinogen (http://monographs.iarc.fr/ENG/Monographs/vol102/mono102.pdf).

Since then more studies have been published that strengthen the association between use of  wireless phones (mobile and cordless phones) and increased risk for brain tumours. We have performed long-term research in this area and in the following we give a short up-dated summary of our findings based on research since the 1990’s. In our publications relevant information can be found also on other studies, as well as discussions of the current scientific evidence.

Glioma:

Glioma is a malignant brain tumour (“brain cancer”), and the most common type is glioblastoma multiforme with a poor prognosis. We have published a statistically significant increased risk for glioma among users of both mobile and cordless phones. The risk increased with latency (time from first use of the phone) and cumulative number of hours for use. Highest risk was found in the area of the brain with highest exposure to RF-EMF. All these results are of biological relevance; that is what would be expected for a causal association. The full paper can be read here: http://www.pathophysiologyjournal.com/article/S0928-4680(14)00064-9/pdf

Meningioma:

Meningioma is mostly a benign brain tumour and accounts for about 30 % of all intracranial tumours. The incidence is approximately 2-times higher in women than in men. No conclusive evidence of an association between use of mobile and cordless phones and meningioma was found in our study. However, taking the long latency periods that have been reported for the increased meningioma risk associated with exposure to ionizing radiation it is still too early to make a definitive risk assessment. Results for even longer latency periods of wireless phone use than in our study are desirable, see more details here: http://www.spandidos-publications.com/or/33/6/3093

 Acoustic neuroma:

Acoustic neuroma or Vestibular Schwannoma is a rare benign tumour in the eighth cranial nerve that leads from the inner ear to the brain. It grows slowly and does not undergo malignant transformation, but may give compression of vital brain stem centres. Tinnitus and hearing problems are usual first symptoms of acoustic neuroma. We published a clear, statistically significant, association between use of mobile and cordless phones and acoustic neuroma. The risk increased with time since first use. For use of both mobile and cordless phones the risk was highest in the longest latency group. Tumour volume increased per 100 hours of cumulative use and year of latency for wireless phones indicating tumour progression from RF-EMF. The whole study can be read here: http://www.spandidos-publications.com/ijo/43/4/1036

Brain tumour incidence:

It is not correct to claim that the incidence of brain tumours has not increased in the Scandinavian countries. The age-standardized incidence of brain tumours increased dramatically in Denmark with +41.2 % among men and +46.1 % among women during 2003-2012 (http://www.ssi.dk/Aktuelt/Nyheder/2013/~/media/Indhold/DK – dansk/Sundhedsdata og it/NSF/Registre/Cancerregisteret/Cancerregisteret 2012.ashx).

Due to the well-known under-reporting of brain tumours to the Swedish Cancer Registry we studied brain tumour rates using the Swedish National Inpatient Register and the Causes of Death Register. In summary we found a statistically significant increasing rate of not specified brain tumours from 2007 in the Inpatient Register and from 2008 in the Causes of Death Register. Our study indicated that several of these tumours were never reported to the Swedish Cancer Register. Thus, the Swedish Cancer Register data cannot be used to dismiss an increased risk for brain tumours associated with use of wireless phones. On the contrary our study is consistent with an association considering a reasonable tumour induction period, see more here: http://www.mdpi.com/1660-4601/12/4/3793

Mechanistic aspects:

It is correct that RF-EMFs do not cause direct DNA damage. On the other hand numerous studies have shown generation of reactive oxygen species (ROS) that can cause oxidative damage of DNA. This is a well-known mechanism in carcinogenesis for many agents. The broad biological potential of ROS and other free radicals makes radiofrequency radiation a potentially hazardous factor for human health, not only cancer risk but also other health effects. A recent update can be read here: http://informahealthcare.com/doi/abs/10.3109/15368378.2015.1043557

Causality:

To further evaluate strengths of evidence Bradford Hill wrote in the 1960’s a famous article on association or causation at the height of the tobacco and lung cancer controversy. Hill offered a list of nine aspects of an association to be considered when deciding if an association is causal. However, he did not request all nine viewpoints to be fulfilled for causality. We used the Hill criteria to evaluate the causality on brain tumor risk from RF-EMF emitted from wireless phones. We concluded that based on the Hill criteria, glioma and acoustic neuroma should be considered to be caused by RF-EMF emissions from wireless phones and regarded as carcinogenic to humans, classifying it as Group 1 according to the IARC classification. Current guidelines for exposure need to be urgently revised. See more here: http://www.degruyter.com/view/j/reveh.2013.28.issue-2-3/reveh-2013-0006/reveh-2013-0006.xml

Conclusion:

Our results are in agreement with other studies such as the international Interphone study and the French so called CERENAT study. This is discussed in e.g. our article on glioma risk. In summary there is consistent evidence of increased risk for glioma and acoustic neuroma associated with use of mobile phones and cordless phones. Furthermore, the risk is highest for persons with first use before the age of 20, which is of special concern. Our conclusion is that RF-EMF should be regarded as a human carcinogen. The IARC classification should be updated to at least Group 2A, a probable human carcinogen. It is necessary to give the public correct information on the cancer risk. The precautionary principle should be used to minimize exposure to RF-EMF. Media have an important role to inform in a balanced way. Unfortunately this article in the New York Times is biased towards the no risk assumption. It should be corrected based on facts and not wishful thinking.

Yours sincerely,

 

Lennart Hardell, MD, PhD

Department of Oncology

University Hospital

SE-701 85 Örebro

Sweden

 

Michael Carlberg, MSc

Department of Oncology

University Hospital

SE-701 85 Örebro

Sweden

 

 

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Meningiom och trådlösa telefoner

Vi publicerade nyligen resultat av våra epidemiologiska studier av risken för hjärntumör av typen meningiom och användning av trådlösa telefoner (mobiltelefoner och trådlösa bordstelefoner; DECT). Studieperioderna omfattade svenska patienter som diagnostiserats 1997-2003 eller 2007-2009; totalt 1625 personer deltog. Jämförelsegruppen bestod av 3500 personer ur befolkningsregistret.

Sammantaget sågs ingen tydligt ökad risk även om risken var något förhöjd för personer med störst antal timmar för användning av trådlös telefon och längst latenstid (antal år från första användning till diagnos av meningiom). Resultaten stämmer överens med andra undersökningar inom området och skiljer sig från våra resultat för gliom (’hjärncancer’) och acusticusneurinom (tumör på hörselnerven) där vi sett ett klart samband med trådlösa telefoner.

Studien är publicerad i en vetenskaplig tidning efter sedvanlig förhandsgranskning och kan återfinnas här.

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Ny studie bekräftar ökad risk för gliom (hjärncancer) för personer som använder mobiltelefon

Den 9 maj 2014 publicerades resultaten av en ny fransk studie om sambandet mellan användning av mobiltelefon och risken för hjärntumörer. Det är en fall-kontroll studie och ingår i CERENAT. Undersökningen bekräftar en statistiskt säkerställd ökad risk för de personer som är de tyngsta användarna av mobiltelefoner. Livslång kumulativ användning > 896 timmar gav oddskvot (OR) = 2,89, 95 % konfidensintervall (CI) = 1,41-5,93. Antal samtal > 18 360 gav OR = 2,10, 95 % CI = 1,03-4,31. För personer som använt sin mobiltelefon första gången minst 5 år före diagnosen av gliom ökade risken ytterligare till OR = 5,30, 95 % CI = 2,12-13,23.

Studien visar ökad risk för analoga telefoner; OR = 3,75, 95 % CI = 0,97-14,43, men även för endast digital typ; OR = 2,71, 95 % CI = 1,03-7,10. Risken är högre för tumörer i tinningloben av hjärnan, yrkesmässig användning och i stadsmiljö. Tyvärr inkluderades inte användning av trådlös bordstelefon (DECT) vilket leder till underskattning av risken eftersom även dessa telefoner vid handhållen användning ger exponering till hjärnan av radiofrekventa elektromagnetiska fält (RF-EMF).

Studien inkluderade även meningiom, en godartad hjärntumör. Statistiskt säkerställd ökad risk påvisades för kumulativ användning > 896 timmar med OR = 2,57, 95 % CI = 1,02-6,44. Överlag var dock resultaten för meningiom inte lika entydiga som för gliom för ett samband för användning av mobiltelefoner.

Artikeln redovisar viktiga fynd som starkt bidrar till slutsatsen att gliom orsakas av exponering för RF-EMF. Den styrker resultatet av vår tidigare bedömning om ett orsakssamband om de så kallade Hillkriterierna används.

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Meningiom och trådlösa telefoner

Tidigare undersökningar av vår forskargrupp och Interphone-studien vid IARC (WHO) har inte visat ökad risk för godartad tumör på hjärnhinnan (meningiom) för användning av trådlösa telefoner. För elakartade hjärntumörer, de flesta utgörs av gliom, och acusticus neurinom (tumör på hörselnerven) visar resultaten däremot klart ökad risk.

I vår nya studie för perioden 2007-2009 ingick meningiom som en av grupperna av hjärntumörer. Något klart samband med mobiltelefoner eller trådlösa bordstelefoner (DECT) ses inte heller i denna nya studie, som utan kostnad kan laddas ner från nätet.

I samma undersökning ingick liksom tidigare tre tumörgrupper; elakartade (maligna) hjärntumörer, acusticus neurinom och meningiom. Trådlösa telefoner ökar risken för maligna hjärntumörer och acusticus neurinom i motsats till meningiom.

Resultatet 2007-2009 bekräftar våra tidigare fynd för studieperioden 1997-2003. Eftersom olika resultat fås för de olika tumörtyperna talar detta starkt mot systematiskt fel i studierna. I så fall hade resultatet varit likadant oavsett tumörtyp. Slutsatsen är att radiofrekventa elektromagnetiska fält från trådlösa telefoner kan ge upphov till elakartade hjärntumörer och acusticusneurinom. För uppföljningstid om nu 25 år av användning i vår nya undersökning ses ingen säkerställd riskökning för meningiom.

Vår studie är den enda i världen än så länge som visar resultat för långtidsanvändning, mer än 20 år, av trådlösa telefoner. Tiden för uppkomst av olika tumörtyper kan variera kraftigt. Därför behövs ytterligare uppföljning för att klart kunna utesluta ökad risk för meningiom på lång sikt.

 

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Incidensen av hjärntumörer ökar i Australien

Incidensen av primära hjärntumörer studerades i två områden i Australien med över 7 miljoner invånare, state of South Wales och Australian Capital Territory, under tidsperioden 2000-2008. Undersökningen var heltäckande och samtliga diagnoser var mikroskopiskt verifierade. Studien inkluderade samtliga 13 databaser vid patologiska kliniker och 24 neurokirurgiska enheter. Den är än så länge den enda i världen av sitt slag med heltäckande registrering av hjärntumörer.

Incidensen av hjärntumörer ökade med ungefär 35 % mellan 2000 till 2008, årligen med 3,5 % vilket var statistiskt signifikant. Särskilt stor ökning sågs för den mest elakartade formen av gliom (glioblastoma multiforme). Det är den tumörtyp som vi sett trådlösa telefoner ger störst riskökning för.

Ökad incidens sågs även för meningiom för män. Däremot sågs minskande incidens av acusticusneurinom (Schwannom). Författarna diskuterar kort att ändrad behandling av denna tumörtyp med stereotaktisk kirurgi utan mikroskopisk bedömning kan var en bidragande orsak.

Författarnas slutsats är att fortsatta analyser av tidstrender av hjärntumörer med databaser av hög kvalitet är viktiga för att identifiera riskfaktorer.

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