Syndication

sabato 29 settembre 2012

Nuovo studio Finlandese sull'uso del telefono cellulare


Qui il documento prodotto, in inglese


E' un'indagine epidemiologica svolta dall'Istituto Finlandese sulla Salute  Occupazionale.in parte coordinato con il Progetto Internazionale COSMOS.
Il progetto è stato denominato WIRECOM = Wireless Communication Devices and Human Health.

 Risultati:

- Mal di testa ha almeno qualche volta limitato le usuali attività quotidiane per il 12% dei partecipanti allo studio e circa il 24% era stato disturbato dalla luce quando si ha un mal di testa.
In media il 15% ritiene la propria salute sia equo o compromessa.
Inoltre, i partecipanti hanno riferito i sintomi che si verificano in relazione l'uso del telefono cellulare. Quasi il 10% degli intervistati ha riferito mal di testa, tinnito 15% e il 10% la perdita di udito parziale, in combinato disposto con l'uso del telefono cellulare (sempre, spesso o qualche volta contro mai). Nausea è la sensazione minimo comune (3%) e bruciore nell'orecchio è stato il sintomo più comune (49%).
 
 - due studi sono stati condotti con il PET , con la conclusione che il metabolismo del glucosio nel cervello è sensibilmente ridotto nelle parti del cervello compatibili con l'uso del telefono
- Nel gruppo adulto, il valore SAR di 4 W / kg è stato utilizzato negli esperimenti. È superiore al valore massimo consentito normale GSM SAR di 2 W / kg, ma chiaramente inferiori ai limiti di sicurezza per esposizione a RF. Durante il tempo di esposizione di 20 minuti, una leggera diminuzione degli indicatori di flusso sanguigno della zona frontale è stato trovato. Questo risultato è in accordo con i risultati del Centro di Turku University s per lo studio Neuroscienze Cognitive PET.
La temperatura del canale uditivo aumentata di circa 0,5 ° C durante il tempo di esposizione 20 min. I campioni di sangue sono stati prelevati solo nel gruppo degli adulti, prima e dopo la seduta. La proteina S100 B è prodotto principalmente nel cervello dagli astrociti. ed è stato suggerito per servire come strumento di screening di lesioni CNS. Durante l'esposizione, la concentrazione S100B è diminuito significativamente
___________________________________________________________________________________
EXECUTIVE SUMMARY
The rapid spread of mobile phones and other wireless communication devices has in-creased the population’s exposure to electromagnetic fields at radio frequencies (RF).Even though the electromagnetic fields emitted by mobile phones and base stations areweak compared to safety limits, public discussion and some research findings have raisedconcern about possible health effects.During the years 1994 – 2007, four national research programmes were carried out inFinnish universities and research institutes, funded mainly by TEKES. The programmesattempted to respond to citizens’ concerns about the possible adverse health effects of mobile phones, and they were part of international cooperation to evaluate the healthrisks of electromagnetic fields at radio frequencies. Although these Finnish and foreignstudies generated a lot of information, there remain still some open questions. Therefore,in January 2009, a new national research project into the health effects of mobile phones’ RF fields was started. The objective was to enable large-scale and reliable research inindependent research institute, hence ensuring public benefit from the findings.The joint project WIRECOM (Wireless Communication Devices and Human Health), wasmade up of four different projects, containing a large-scale international cooperation thatincludes epidemiological monitoring research as well as provocative projects focussing onpossible effects on the head area. The projects dealt with the research questions thatwere the highest priority for the World Health Organisation (WHO), thus supporting theWHO’s planned evaluation of the health risks of RF fields.

The focus of the Finnish Institute of Occupational Health’s (FIOH) sub-project was to clar-ify whether the exposure of trial subjects to the RF fields from GSM phones produces lev-els of temperature change in the tissues of the head area which could be detrimental tothe health of the phone user.

The results of the volunteer tests by preadolescent boys and young adults indicated no significant increase in local ear canal temperatures or superficialcerebral blood flow. Alterations in peripheral thermoregulatory or circulatory autonomicreflexes typically related to the increase in the temperature of brain thermostat were nei-ther found. With the preadolescents boys the used phone transmitting power was themaximum allowed for the general public ( 2 W/kg).In the adult group, the SAR value of 4 W/kg was used in the experiments. It is higherthan the normal allowed maximum GSM SAR value of 2 W/kg, but clearly below thesafety limits for RF exposures. During the exposure time of 20 min, a slight decrease inthe blood flow indicators of the frontal area was found. This finding is in accordance withresults of Turku University’s Centre for Cognitive Neurosciences PET study. The ear canaltemperature increased about 0.5 °C during the 20 min exposure time. The blood sampleswere taken only in the adult group before and after the session. The protein S100 B ismainly produced in the brain by astrocytes. and it has been suggested to serve as ascreening tool of CNS injury. During the exposure the S100B concentration decreasedsignificantly (p<0,01). The levels, however, were within biological normal range both before and after the exposure. Any other significant changes were not found in other bio-chemical markers.The primary interests of the Centre for Cognitive Neuroscience of University of Turku(UTU) were in the possible link between RF exposure and metabolic changes in brain tis-sue, as well as in the link between functional changes in neurobiological mechanisms andcognitive functions. The research was carried out in cooperation with the national PETCentre. Two positron emission tomography (PET) studies were conducted to investigatethe effects of mobile phone radiation on brain glucose metabolism and cerebral blood flow(CBF) using fluorodeoxyglucose ([18F]FDG) and radioactive water ([15O]H2O), respec-tively. The main finding of the FDG-PET study was that the brain glucose metabolism wassignificantly reduced in the temporoparietal junction and anterior temporal lobe of theexposed (right) hemisphere. The SAR value during the exposure was 0.25 W/kg.The Radiation and Nuclear Safety Authority (STUK) was responsible for the construction of the exposure device for the subjects and for measuring exposure (dosimetry) in the othersub-projects. The quality of the numerical source model used was found adequate bycomparing the measured and simulated SAR values in a homogeneous liquid phantom.Also the simulated return loss and center frequencies agreed well with the measured val-ues. The high quality dosimetric assessment of the exposure systems is essential re-quirement for reliable human exposure studies.The fourth sub-project was also carried out by STUK, consisting of monitoring researchinto mobile phone users as part of a large-scale European project. The Finnish COSMOSstudy is a part of international collaborative COSMOS study with a common study proto-col. Besides Finland, national COSMOS study components have been launched in Sweden,Denmark, and the UK (30,000-66,000 participants in each country), and are being pre-pared in the Netherlands and France. International collaboration increases the statisticalpower of the study considerably, which is essential particularly for rare diseases such asbrain tumours (glioma, meningioma) and Parkinson and Alzheimer disease.People who use mobile phones at different levels were invited to take part in the researchand were contacted through their service providers. In the monitoring phase, data aboutthe participants’ incidence rate of illness were collected, and the question as to whetherthere is a link between use of mobile phones and the risk of illness was evaluated. A totalof 15,800 persons have agreed to participate in the study (9.6% of those invited) andabout 13,000 have also filled in the study questionnaire (8.0% of those invited). In thestudy questionnaire participants reported most often having started their use of mobileuse in the mid-1990s. Study participants usually reported having called their mobilephone 1-3 hours per week (38 %); 6 % belonged to the highest category of call time (> 6h per week) and < 1 % belonged to the lowest category (<5 min per week). About 60 %had used one mobile phone and some 5 % had used at least mobile phones during thepreceding three months. Headache had at least sometimes limited usual daily activities for12 % of the study participants and about 24 % had been bothered by light when having aheadache. On average 15 % considered their health being fair or poor. In addition, par-ticipants reported any symptoms occurring in relation to mobile phone use. Almost 10%of the respondent reported headache, 15% tinnitus and 10% partial hearing loss in con- junction with mobile phone use (always, often or sometimes vs. never). Nausea was the least common (3%) and burning sensation in the ear was the most common symptom(49%).All three major Finnish operators (DNA, Elisa and TeliaSonera) agreed to deliver operatordata for the participants upon researchers’ request. Operator data have been receivedfrom all the operators at least for a three month period each year. Study participants arebeing kept up to date about the progress of the study through a newsletter (sent byemail) and through the study web page (www.cosmostutkimus.fi).After the recruitmentperiod, the Finnish COSMOS is now entering the follow-up phase. We aim to send the firstfollow-up questionnaires in 2013 to those recruited in 2009. The study is expected tocontinue until at least 2020 or beyond.

 

OPEN QUESTIONS AND RECOMMENDATIONS

 

Research findings of both FIOH and UTU indicated that the RF exposure from the mobilephone can affect the brain metabolism and cerebral blood flow. However, conflicting re-ports have been published from other research groups on the brain glucose metabolismafter the RF exposure. There is a need for replication of the present results and to deter-mine possible dose-response relations using different RF exposure intensities. It is oneimportant way to evaluate the causality of the events. As the changes in the brain arevery difficult to measure, the research should be designed to use independent methodolo-gies (e.g. PET and NIRS) on the same physiological function. Similar results by independ-ent methods would give more credibility to the results.The effect of local SAR on brain glucose metabolism could be studied in the future with asetup delivering smaller and better defined and targeted exposed volume. With a dipole orplanar antenna the exposure could be targeted to a certain brain lobe. Higher SAR valuescould be used to study the dose-dependence of the changes in metabolism.A major threat for the future of the Finnish research programme is the lack of continuedfunding.

FUNDING
The main funder of the WIRECOM - programme was Tekes – the Finnish Funding Agencyfor Technology and Innovation. The programme received funding also from Nokia, Teli-aSonera and Elisa as well as from the participating research institutes. The Finnish Insti-tute of Occupational Health was the coordinator of the project.


______________________________________________________

New mobile phone research results from Finland

Main findings:

- Headache had at least sometimes limited usual daily activities for 12 % of the study participants and about 24 % had been bothered by light when having a headache. On average 15 % considered their health being fair or poor. In addition, participants reported any symptoms occurring in relation to mobile phone use. Almost 10% of the respondent reported headache, 15% tinnitus and 10% partial hearing loss in conjunction with mobile phone use (always, often or sometimes vs. never). Nausea was the least common (3%) and burning sensation in the ear was the most common symptom (49%).

- Two positron emission tomography (PET) studies were conducted to investigate the effects of mobile phone radiation on brain glucose metabolism and cerebral blood flow (CBF) using fluorodeoxyglucose ([18F]FDG) and radioactive water ([15O]H2O), respectively. The main finding of the FDG-PET study was that the brain glucose metabolism was significantly reduced in the temporoparietal junction and anterior temporal lobe of the exposed (right) hemisphere. The SAR value during the exposure was 0.25 W/kg.

- In the adult group, the SAR value of 4 W/kg was used in the experiments. It is higher than the normal allowed maximum GSM SAR value of 2 W/kg, but clearly below the safety limits for RF exposures. During the exposure time of 20 min, a slight decrease in the blood flow indicators of the frontal area was found. This finding is in accordance with results of Turku University s Centre for Cognitive Neurosciences PET study. The ear canal temperature increased about 0.5 °C during the 20 min exposure time. The blood samples were taken only in the adult group before and after the session. The protein S100 B is mainly produced in the brain by astrocytes. and it has been suggested to serve as a screening tool of CNS injury. During the exposure the S100B concentration decreased significantly.

http://www.ttl.fi/en/publications/Electronic_publications/Documents/WIRECOM.pdf

Nessun commento:

Posta un commento