Browsing by Author "Söderqvist, Fredrik"
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- ItemCase-control study of the association between malignant brain tumours diagnosed between 2007 and 2009 and mobile and cordless phone use.(2013-10-22) Hardell, Lennart; Carlberg, Michael; Söderqvist, Fredrik; Mild, Kjell HanssonPrevious studies have shown a consistent association between long term use of mobile and cordless phones and glioma and acoustic neuroma but not for meningioma When used these phones emit radiofrequency electromagnetic fields RF EMFs and the brain is the main target organ for the handheld phone The International Agency for Research on Cancer IARC classified in May 2011 RF EMF as a group 2B i e a possible human carcinogen The aim of this study was to further explore the relationship between especially long term 10 years use of wireless phones and the development of malignant brain tumours We conducted a new case control study of brain tumour cases of both genders aged 18 75 years and diagnosed during 2007 2009 One population based control matched on gender and age within 5 years was used to each case Here we report on malignant cases including all available controls Exposures on e g use of mobile phones and cordless phones were assessed by a self administered questionnaire Unconditional logistic regression analysis was performed adjusting for age gender year of diagnosis and socio economic index using the whole control sample Of the cases with a malignant brain tumour 87 n 593 participated and 85 n 1 368 of controls in the whole study answered the questionnaire The odds ratio OR for mobile phone use of the analogue type was 1 8 95 confidence interval CI 1 04 3 3 increasing with 25 years of latency time since first exposure to an OR 3 3 95 CI 1 6 6 9 Digital 2G mobile phone use rendered an OR 1 6 95 CI 0 996 2 7 increasing with latency 15 20 years to an OR 2 1 95 CI 1 2 3 6 The results for cordless phone use were OR 1 7 95 CI 1 1 2 9 and for latency of 15 20 years the OR 2 1 95 CI 1 2 3 8 Few participants had used a cordless phone for 20 25 years Digital type of wireless phones 2G and 3G mobile phones cordless phones gave increased risk with latency 1 5 years then a lower risk in the following latency groups but again increasing risk with latency 15 20 years Ipsilateral use resulted in a higher risk than contralateral mobile and cordless phone use Higher ORs were calculated for tumours in the temporal and overlapping lobes Using the meningioma cases in the same study as reference entity gave somewhat higher ORs indicating that the results were unlikely to be explained by recall or observational bias This study confirmed previous results of an association between mobile and cordless phone use and malignant brain tumours These findings provide support for the hypothesis that RF EMFs play a role both in the initiation and promotion stages of carcinogenesis
- ItemChildhood brain tumour risk and its association with wireless phones: a commentary.(2012-02-14) Söderqvist, Fredrik; Carlberg, Michael; Hansson Mild, Kjell; Hardell, LennartCase control studies on adults point to an increased risk of brain tumours glioma and acoustic neuroma associated with the long term use of mobile phones Recently the first study on mobile phone use and the risk of brain tumours in children and adolescents CEFALO was published It has been claimed that this relatively small study yielded reassuring results of no increased risk We do not agree We consider that the data contain several indications of increased risk despite low exposure short latency period and limitations in the study design analyses and interpretation The information certainly cannot be used as reassuring evidence against an association for reasons that we discuss in this commentary
- ItemExposure to an 890-MHz mobile phone-like signal and serum levels of S100B and transthyretin in volunteers.(2009-06-22) Söderqvist, Fredrik; Carlberg, Michael; Hansson Mild, Kjell; Hardell, LennartWhether low intensity non thermal microwave radiation alters the integrity of the blood brain barrier has been debated since the late 1970s yet no experimental study has been carried out on humans The aim of this study was to test using peripheral markers whether exposure to a mobile phone like signal alters the integrity of the human blood brain and blood cerebrospinal fluid barriers A provocation study was carried out that exposed 41 volunteers to a 30 min GSM 890 MHz signal with an average specific energy absorption rate distribution of 1 0 W kg in the temporal area of the head as measured over any 1g of contiguous tissue The outcome was assessed by changes in serum concentrations of two putative markers of brain barrier integrity S100B and transthyretin Repeated blood sampling before and after the provocation showed no statistically significant increase in the serum levels of S100B while for transthyretin a statistically significant increase was seen in the final blood sample 60 min after the end of the provocation as compared to the prior sample taken immediately after provocation p 0 02 The clinical significance of this finding if any is unknown Further randomized studies with use of additional more brain specific markers are needed
- ItemExposure to wireless phone emissions and serum beta-trace protein.(2010-07-02) Hardell, Lennart; Söderqvist, Fredrik; Carlberg, Michael; Zetterberg, Henrik; Mild, Kjell HanssonThe lipocalin type of prostaglandin D synthase or beta trace protein is synthesized in the choroid plexus lepto meninges and oligodendrocytes of the central nervous system and is secreted into the cerebrospinal fluid beta trace protein is the key enzyme in the synthesis of prostaglandin D2 an endogenous sleep promoting neurohormone in the brain Electromagnetic fields EMF in the radio frequency RF range have in some studies been associated with disturbed sleep We studied the concentration of beta trace protein in blood in relation to emissions from wireless phones This study included 62 persons aged 18 30 years The concentration of beta trace protein decreased with increasing number of years of use of a wireless phone yielding a negative beta coefficient 0 32 95 confidence interval 0 60 to 0 04 Also cumulative use in hours gave a negative beta coefficient although not statistically significant Of the 62 persons 40 participated in an experimental study with 30 min exposure to an 890 MHz GSM signal No statistically significant change of beta trace protein was found In a similar study of the remaining 22 participitants with no exposure beta trace protein increased significantly over time probably due to a relaxed situation EMF emissions may down regulate the synthesis of beta trace protein This mechanism might be involved in sleep disturbances reported in persons exposed to RF fields The results must be interpreted with caution since use of mobile and cordless phones were self reported Awareness of exposure condition in the experimental study may have influenced beta trace protein concentrations
- Item[Fragmentary reporting of health risks associated with mobile phones].(2011-11-24) Söderqvist, Fredrik
- ItemLong-term use of cellular phones and brain tumours: increased risk associated with use for > or =10 years.(2007-08-20) Hardell, Lennart; Carlberg, Michael; Söderqvist, Fredrik; Mild, Kjell Hansson; Morgan, L LloydTo evaluate brain tumour risk among long term users of cellular telephones
- ItemMeningioma patients diagnosed 2007-2009 and the association with use of mobile and cordless phones: a case-control study.(2014-07-23) Carlberg, Michael; Söderqvist, Fredrik; Hansson Mild, Kjell; Hardell, LennartTo study the association between use of wireless phones and meningioma
- ItemMeta-analysis of long-term mobile phone use and the association with brain tumours.(2008-04-21) Hardell, Lennart; Carlberg, Michael; Söderqvist, Fredrik; Hansson Mild, KjellWe evaluated long term use of mobile phones and the risk for brain tumours in case control studies published so far on this issue We identified ten studies on glioma and meta analysis yielded OR 0 9 95 CI 0 8 1 1 Latency period of or 10 years gave OR 1 2 95 CI 0 8 1 9 based on six studies for ipsilateral use same side as tumour OR 2 0 95 CI 1 2 3 4 four studies but contralateral use did not increase the risk significantly OR 1 1 95 CI 0 6 2 0 Meta analysis of nine studies on acoustic neuroma gave OR 0 9 95 CI 0 7 1 1 increasing to OR 1 3 95 CI 0 6 2 8 using or 10 years latency period four studies Ipsilateral use gave OR 2 4 95 CI 1 1 5 3 and contra lateral OR 1 2 95 CI 0 7 2 2 in the or 10 years latency period group three studies Seven studies gave results for meningioma yielding overall OR 0 8 95 CI 0 7 0 99 Using or 10 years latency period OR 1 3 95 CI 0 9 1 8 was calculated four studies increasing to OR 1 7 95 CI 0 99 3 1 for ipsilateral use and OR 1 0 95 CI 0 3 3 1 for contralateral use two studies We conclude that this meta analysis gave a consistent pattern of an association between mobile phone use and ipsilateral glioma and acoustic neuroma using or 10 years latency period
- ItemOwnership and use of wireless telephones: a population-based study of Swedish children aged 7-14 years.(2007-07-03) Söderqvist, Fredrik; Hardell, Lennart; Carlberg, Michael; Hansson Mild, KjellRecent years have seen a rapid increase in the use of mobile phones and other sources of microwave radiation raising concerns about possible adverse health effects As children have longer expected lifetime exposures to microwaves from these devices than adults who started to use them later in life they are a group of special interest
- ItemPooled analysis of case-control studies on acoustic neuroma diagnosed 1997-2003 and 2007-2009 and use of mobile and cordless phones.(2013-08-14) Hardell, Lennart; Carlberg, Michael; Söderqvist, Fredrik; Mild, Kjell HanssonWe previously conducted a case control study of acoustic neuroma Subjects of both genders aged 20 80 years diagnosed during 1997 2003 in parts of Sweden were included and the results were published We have since made a further study for the time period 2007 2009 including both men and women aged 18 75 years selected from throughout the country These new results for acoustic neuroma have not been published to date Similar methods were used for both study periods In each one population based control matched on gender and age within five years was identified from the Swedish Population Registry Exposures were assessed by a self administered questionnaire supplemented by a phone interview Since the number of acoustic neuroma cases in the new study was low we now present pooled results from both study periods based on 316 participating cases and 3 530 controls Unconditional logistic regression analysis was performed adjusting for age gender year of diagnosis and socio economic index SEI Use of mobile phones of the analogue type gave odds ratio OR 2 9 95 confidence interval CI 2 0 4 3 increasing with 20 years latency time since first exposure to OR 7 7 95 CI 2 8 21 Digital 2G mobile phone use gave OR 1 5 95 CI 1 1 2 1 increasing with latency 15 years to an OR 1 8 95 CI 0 8 4 2 The results for cordless phone use were OR 1 5 95 CI 1 1 2 1 and for latency of 20 years OR 6 5 95 CI 1 7 26 Digital type wireless phones 2G and 3G mobile phones and cordless phones gave OR 1 5 95 CI 1 1 2 0 increasing to OR 8 1 95 CI 2 0 32 with latency 20 years For total wireless phone use the highest risk was calculated for the longest latency time 20 years OR 4 4 95 CI 2 2 9 0 Several of the calculations in the long latency category were based on low numbers of exposed cases Ipsilateral use resulted in a higher risk than contralateral for both mobile and cordless phones OR increased per 100 h cumulative use and per year of latency for mobile phones and cordless phones though the increase was not statistically significant for cordless phones The percentage tumour volume increased per year of latency and per 100 h of cumulative use statistically significant for analogue phones This study confirmed previous results demonstrating an association between mobile and cordless phone use and acoustic neuroma
- ItemRadiofrequency fields, transthyretin, and Alzheimer's disease.(2010-05-27) Söderqvist, Fredrik; Hardell, Lennart; Carlberg, Michael; Mild, Kjell HanssonRadiofrequency field RF exposure provided cognitive benefits in an animal study In Alzheimer s disease AD mice exposure reduced brain amyloid beta Abeta deposition through decreased aggregation of Abeta and increase in soluble Abeta levels Based on our studies on humans on RF from wireless phones we propose that transthyretin TTR might explain the findings In a cross sectional study on 313 subjects we used serum TTR as a marker of cerebrospinal fluid TTR We found a statistically significantly positive beta coefficient for TTR for time since first use of mobile phones and desktop cordless phones combined P 0 03 The electromagnetic field parameters were similar for the phone types In a provocation study on 41 persons exposed for 30 min to an 890 MHz GSM signal with specific absorption rate of 1 0 Watt kg to the temporal area of the brain we found statistically significantly increased serum TTR 60 min after exposure In our cross sectional study use of oral snuff also yielded statistically significantly increased serum TTR concentrations and nicotine has been associated with decreased risk for AD and to upregulate the TTR gene in choroid plexus but not in the liver another source of serum TTR TTR sequesters Abeta thereby preventing the formation of Abeta plaques in the brain Studies have shown that patients with AD have lowered TTR concentrations in the cerebrospinal fluid and have attributed the onset of AD to insufficient sequestering of Abeta by TTR We propose that TTR might be involved in the findings of RF exposure benefit in AD mice
- ItemRe: Time trends in brain tumor incidence rates in Denmark, Finland, Norway, and Sweden, 1974-2003.(2010-05-20) Hardell, Lennart; Carlberg, Michael; Söderqvist, Fredrik; Mild, Kjell Hansson
- ItemReview of four publications on the Danish cohort study on mobile phone subscribers and risk of brain tumors.(2012-07-04) Söderqvist, Fredrik; Carlberg, Michael; Hardell, LennartSince the International Agency for Research on Cancer recently classified radiofrequency electromagnetic fields such as those emanating from mobile and cordless phones as possibly carcinogenic to humans group 2B two additional reports relevant to the topic have been published Both articles were new updates of a Danish cohort on mobile phone subscribers and concern the possible association between assumed use of mobile phones and risk of brain tumors The aim of the present review is to reexamine all four publications on this cohort
- ItemTumour risk associated with use of cellular telephones or cordless desktop telephones.(2006-10-24) Hardell, Lennart; Mild, Kjell Hansson; Carlberg, Michael; Söderqvist, FredrikBACKGROUND The use of cellular and cordless telephones has increased dramatically during the last decade There is concern of health problems such as malignant diseases due to microwave exposure during the use of these devices The brain is the main target organ METHODS Since the second part of the 1990 s we have performed six case control studies on this topic encompassing use of both cellular and cordless phones as well as other exposures Three of the studies concerned brain tumours one salivary gland tumours one non Hodgkin lymphoma NHL and one testicular cancer Exposure was assessed by self administered questionnaires RESULTS Regarding acoustic neuroma analogue cellular phones yielded odds ratio OR 2 9 95 confidence interval CI 2 0 4 3 digital cellular phones OR 1 5 95 CI 1 1 2 1 and cordless phones OR 1 5 95 CI 1 04 2 0 The corresponding results were for astrocytoma grade III IV OR 1 7 95 CI 1 3 2 3 OR 1 5 95 CI 1 2 1 9 and OR 1 5 95 CI 1 1 1 9 respectively The ORs increased with latency period with highest estimates using 10 years time period from first use of these phone types Lower ORs were calculated for astrocytoma grade I II No association was found with salivary gland tumours NHL or testicular cancer although an association with NHL of T cell type could not be ruled out CONCLUSION We found for all studied phone types an increased risk for brain tumours mainly acoustic neuroma and malignant brain tumours OR increased with latency period especially for astrocytoma grade III IV No consistent pattern of an increased risk was found for salivary gland tumours NHL or testicular cancer
- ItemUse of wireless phones and serum β-trace protein in randomly recruited persons aged 18-65 years: a cross-sectional study.(2012-11-08) Söderqvist, Fredrik; Carlberg, Michael; Zetterberg, Henrik; Hardell, LennartBACKGROUND There are studies suggesting effects on sleep from pulse modulated radiofrequency fields used in mobile and cordless phones So far reports of adverse effects in observational studies are of limited value for risk assessment while effects from experimental studies seem to be more consistent but unclear as to their importance for health The aim of this study was to investigate whether use of wireless phones is associated with lower concentrations of trace protein lipocalin type prostaglandin D synthase a key enzyme in the synthesis of prostaglandin D 2 an endogenous sleep promoting neurohormone METHODS Three hundred and fourteen people aged 18 65 years and living in the municipality of rebro Sweden were recruited randomly using the population registry Total and age specific linear regression analyses adjusted for known covariates were used to calculate associations between levels of trace protein and short and long term use of wireless phones RESULTS Overall no statistically significant association between use of wireless phones and the serum concentration of trace protein was found neither with respect to short term nor long term use Age specific analyses however yielded negative associations for long term use cumulative hours of use and trace protein in the youngest age group 18 30 years CONCLUSION This study provided no overall evidence of an association between wireless phone use and serum concentrations of trace protein While the findings in the 18 30 year age group indicating lower concentrations with more cumulative hours of use should be further investigated no causal inferences can be made from the results of the present study
- ItemUse of wireless phones and the risk of salivary gland tumours: a case-control study.(2012-09-27) Söderqvist, Fredrik; Carlberg, Michael; Hardell, LennartThe last decades of increasing use of wireless phones including mobile as well as cordless desktop phones have led to concerns about the potential carcinogenic effects of radiofrequency electromagnetic fields Among the most exposed areas of the body when the phone is used for talking are the salivary glands mainly the parotid gland located in front of the ear The objective of this case control study was to assess whether the use of wireless phones is associated with an increased risk of tumour at this site Sixty nine patients with salivary gland tumours 63 with a parotid gland tumour and 262 randomly recruited controls were included Unconditional logistic regression adjusted for age at diagnosis sex year of diagnosis and socioeconomic index was used to produce odds ratios and 95 confidence intervals The use of wireless phones was not associated with an overall increased risk of salivary gland tumours odds ratio 0 8 95 confidence interval 0 4 1 5 Neither was there an increased risk for the different phone types when calculated separately nor was there an increased risk for different latencies or when cumulative use was divided into three groups 1 1000 1001 2000 and 2000 h The overall results were similar for the risk of parotid gland tumours In conclusion our data add to the evidence against there being an increased risk for parotid gland tumours associated with light to moderate use of wireless phones and for less than 10 years of use but offers little information on risk related to more prolonged and or heavy use
- ItemUse of wireless telephones and self-reported health symptoms: a population-based study among Swedish adolescents aged 15-19 years.(2008-06-19) Söderqvist, Fredrik; Carlberg, Michael; Hardell, LennartBACKGROUND Despite the last years of rapid increase in use of wireless phones little data on the use of these devices has been systematically assessed among young persons The aim of this descriptive cross sectional study was to assess use of wireless phones and to study such use in relation to explanatory factors and self reported health symptoms METHODS A postal questionnaire comprising 8 pages of 27 questions with 75 items in total was sent to 2000 Swedish adolescents aged 15 19 years and selected from the population registry using a stratified sampling scheme RESULTS The questionnaire was answered by 63 5 of the study subjects Most participants reported access to a mobile phone 99 6 and use increased with age 55 6 of the 15 year olds and 82 2 of the 19 year olds were regular users Girls generally reported more frequent use than boys Use of wired hands free equipment anytime was reported by 17 4 Cordless phones were used by 81 9 and 67 3 were regular users Watching TV increased the odds ratio for use of wireless phones adjusted for age and gender Some of the most frequently reported health complaints were tiredness stress headache anxiety concentration difficulties and sleep disturbances Regular users of wireless phones had health symptoms more often and reported poorer perceived health than less frequent users CONCLUSION Almost all adolescence in this study used a wireless phone girls more than boys The most frequent use was seen among the older adolescents and those who watched TV extensively The study further showed that perceived health and certain health symptoms seemed to be related to the use of wireless phones However this part of the investigation was explorative and should therefore be interpreted with caution since bias and chance findings due to multiple testing might have influenced the results Potentially this study will stimulate more sophisticated studies that may also investigate directions of associations and whether or to what degree any mediation factors are involved
- ItemUse of wireless telephones and serum S100B levels: a descriptive cross-sectional study among healthy Swedish adults aged 18-65 years.(2008-12-08) Söderqvist, Fredrik; Carlberg, Michael; Hardell, LennartSince the late 1970s experimental animal studies have been carried out on the possible effects of low intensive radiofrequency fields on the blood brain barrier BBB but no epidemiological study has been published to date