The possible role of radiofrequency radiation in the development of uveal melanoma

A tree-based corpus annotated with Cyber-Syndrome, symptoms, and acupoints

Prolonged and over-excessive interaction with cyberspace poses a threat to people's health and leads to the occurrence of Cyber-Syndrome, which covers not only physiological but also psychological disorders. This paper aims to create a tree-shaped gold-standard corpus that annotates the Cyber-Syndrome, clinical manifestations, and acupoints that can alleviate their symptoms or signs, designating this corpus as CS-A. In the CS-A corpus, this paper defines six entities and relations subject to annotation. There are 448 texts to annotate in total manually. After three rounds of updating the annotation guidelines, the inter-annotator agreement (IAA) improved significantly, resulting in a higher IAA score of 86.05%. The purpose of constructing CS-A corpus is to increase the popularity of Cyber-Syndrome and draw attention to its subtle impact on people's health. Meanwhile, annotated corpus promotes the development of natural language processing technology. Some model experiments can be implemented based on this corpus, such as optimizing and improving models for discontinuous entity recognition, nested entity recognition, etc. The CS-A corpus has been uploaded to figshare.

Relationship between parental exposure to radiofrequency electromagnetic fields and primarily hematopoietic neoplasms (lymphoma, leukemia) and tumors in the central nervous system in children: a systematic review

Low-frequency electromagnetic fields have grown exponentially in recent years due to technological development and modernization. The World Health Organization (WHO)/International Agency for Research on Cancer (IARC) has classified radiofrequency electromagnetic fields (RF-EMFs) as possibly carcinogenic to humans (Group 2B), and recent studies have investigated the association between exposure to electromagnetic fields in parents and possible health effects in children, especially the development of tumours of the central nervous system (CNS). The objective of this systematic review was to collate all evidence on the relationship between parental occupational exposure to electromagnetic fields and the development of CNS cancer in children and to evaluate this association. This review was prepared according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Embase, and Web of Science were searched from January 1990 to April 2021. The search was conducted using the following search string: "occupational" AND "child" AND "electromagnetic" AND "cancer". Seventeen articles met our inclusion criteria: 13 case-control studies, two cohort studies, and 2 meta-analyses. Most of the studies showed several methodological weaknesses that limited their results. Due to a lack of consistency regarding the outcome as well as the heterogeneity in the reviewed studies, the body of evidence for the effects of parental exposure to electromagnetic fields is not clear. Methodological heterogeneity in the way that studies were conducted could be responsible for the lack of consistency in the findings. Overall, the body of evidence allows no conclusion on the relationship between parental exposure to electromagnetic fields and the occurrence of CNS tumours in children.

5G mobile networks and health-a state-of-the-science review of the research into low-level RF fields above 6 GHz

The increased use of radiofrequency (RF) fields above 6 GHz, particularly for the 5 G mobile phone network, has given rise to public concern about any possible adverse effects to human health. Public exposure to RF fields from 5 G and other sources is below the human exposure limits specified by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). This state-of-the science review examined the research into the biological and health effects of RF fields above 6 GHz at exposure levels below the ICNIRP occupational limits. The review included 107 experimental studies that investigated various bioeffects including genotoxicity, cell proliferation, gene expression, cell signalling, membrane function and other effects. Reported bioeffects were generally not independently replicated and the majority of the studies employed low quality methods of exposure assessment and control. Effects due to heating from high RF energy deposition cannot be excluded from many of the results. The review also included 31 epidemiological studies that investigated exposure to radar, which uses RF fields above 6 GHz similar to 5 G. The epidemiological studies showed little evidence of health effects including cancer at different sites, effects on reproduction and other diseases. This review showed no confirmed evidence that low-level RF fields above 6 GHz such as those used by the 5 G network are hazardous to human health. Future experimental studies should improve the experimental design with particular attention to dosimetry and temperature control. Future epidemiological studies should continue to monitor long-term health effects in the population related to wireless telecommunications.

Development of a Job-Exposure Matrix for Assessment of Occupational Exposure to High-Frequency Electromagnetic Fields (3 kHz-300 GHz)

OBJECTIVES

The aim of this work was to build a job-exposure matrix (JEM) using an international coding system and covering the non-thermal intermediate frequency (IF) (3-100 kHz, named IFELF), thermal IF (100 kHz-10 MHz, named IFRF), and radiofrequency (RF) (>10 MHz) bands.

METHODS

Detailed occupational data were collected in a large population-based case-control study, INTEROCC, with occupations coded into the International Standard Classification of Occupations system 1988 (ISCO88). The subjects' occupational source-based ancillary information was combined with an existing source-exposure matrix and the reference levels of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) for occupational exposure to calculate estimates of level (L) of exposure to electric (E) and magnetic (H) fields by ISCO88 code and frequency band as ICNIRP ratios (IFELF) or squared ratios (IFRF and RF). Estimates of exposure probability (P) were obtained by dividing the number of exposed subjects by the total number of subjects available per job title.

RESULTS

With 36 011 job histories collected, 468 ISCO88 (four-digit) codes were included in the JEM, of which 62.4% are exposed to RF, IFRF, and/or IFELF. As a reference, P values for RF E-fields ranged from 0.3 to 65.0% with a median of 5.1%. L values for RF E-fields (ICNIRP squared ratio) ranged from 6.94 × 10-11 to 33.97 with a median of 0.61.

CONCLUSIONS

The methodology used allowed the development of a JEM for high-frequency electromagnetic fields containing exposure estimates for the largest number of occupations to date. Although the validity of this JEM is limited by the small number of available observations for some codes, this JEM may be useful for epidemiological studies and occupational health management programs assessing high-frequency electromagnetic field exposure in occupational settings.

Uveal Melanoma Risk Factors: A Systematic Review of Meta-Analyses

PURPOSE

There is currently no clinical risk-assessment tool allowing identification of patients at risk for developing uveal melanoma (UM) who might benefit from regular screening. As a first step toward the elaboration of such a tool, we systematically reviewed UM risk factors already established by meta-analysis.

METHODS

Two reviewers independently screened Pubmed, Medline, Embase, and Web of Science from their respective inception dates until July 2016 using a combination of keywords and MeSH terms. Eligible studies were meta-analyses or systematic reviews providing pooled odds ratios (ORs) of risk factors for UM development or sufficient information to calculate them. Methodological quality was evaluated using the Assessment of Multiple Systematic Reviews tool.

RESULTS

Four meta-analyses with a mean methodological quality score of 65.9% (min: 54.5%; max: 72.7%) were included. The following significant risk factors were identified: atypical cutaneous nevi (OR 2.82, 95% CI 1.10-7.26), welding (OR 2.05, 95% CI 1.20-3.51), occupational cooking (OR 1.81, 95% CI 1.33-2.46), fair skin color (OR 1.80, 95% CI 1.31-2.47), light eye color (OR 1.75, 95% CI 1.31-2.34), common cutaneous nevi (OR 1.74, 95% CI 1.27-2.39), propensity to sunburn (OR 1.64, 95% CI 1.29-2.09), iris nevi (OR 1.53, 95% CI 1.03-2.27), and cutaneous freckles (OR 1.27, 95% CI 1.09-1.49). Non-significant factors included outdoor leisure activity, occupational sunlight exposure, latitude of birth, and hair color.

CONCLUSION

Moderate quality of evidence determined nine significant risk factors for developing UM. Knowledge of these variables will assist researchers in the elaboration of a formal risk-assessment tool allowing clinicians to estimate susceptibility to the disease and necessity of regular screening.

Association between Exposure to Smartphones and Ocular Health in Adolescents

PURPOSE

Smartphone use has dramatically increased in recent years. Smartphones may have adverse health effects, particularly on the eyes, because users stare at the screen for a much longer time than they do with ordinary mobile phones. The objective of this study was to elucidate the relationship between smartphone use and ocular symptoms among adolescents.

METHODS

Information on smartphone use and ocular symptoms (blurring, redness, visual disturbance, secretion, inflammation, lacrimation and dryness) related to eye fatigue and strain from 715 adolescent subjects from three cities in Korea was obtained using a structured questionnaire. Ocular health was scored using number of ocular symptoms. Odds ratios (ORs), 95% confidence intervals (95% CIs) and p-values for ocular symptoms were calculated with binomial and multinomial logistic regression models.

RESULTS

Higher prevalence rates for ocular symptoms were observed in groups with greater exposure to smartphones (p < 0.05). Longer daily smartphone use was associated with a higher likelihood of having multiple ocular symptoms (5-7 symptoms out of 7 symptoms; p = 0.005). Excessive/intermittent use (>2 hours daily and ≤2 hours continuously) and excessive/persistent use (>2 hours daily and >2 hours continuously) compared to shorter use (<2 hours daily) were associated with multiple ocular symptoms (OR 2.18, 95% CI 1.09-4.39; OR 2.26, 95% CI 1.11-4.57, respectively). A higher lifetime exposure to smartphones was associated with a higher likelihood of having multiple ocular symptoms (OR 3.05, 95% CI 1.51-6.19; p = 0.001).

CONCLUSION

Increasing exposure to smartphones can have a negative impact on ocular health in adolescents.

Mobile phone use and risk of glioma: a case-control study in Korea for 2002-2007

OBJECTIVES

There has been a growing concern about the possible carcinogenic effects of the electromagnetic radiofrequency fields emitted from mobile phones. The purpose of this study was to investigate the association between mobile phone use and the development of gliomas in Korea.

METHODS

Our study methods were based on the International Interphone study that aimed to evaluate possible adverse effects of mobile phone use. This study included 285 histologically-confirmed Korean patients 15 to 69 years of age, with gliomas diagnosed between 2002 and 2007 in 9 hospitals. The 285 individually matched controls were healthy individuals that had their medical check-up in the same hospitals. Unconditional logistic regression was used to calculate the adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for use of mobile phones.

RESULTS

For the entire group, no significant relationship was investigated between gliomas and regular use of mobile phones, types of mobile phones, lifetime years of use, monthly service fee, and the other exposure indices. Analyses restricted to self-respondents showed similar results. For ipsilateral users, whose the body side for usual mobile phone use match the location of glioma, the aORs (95% CIs) for lifetime years of use and cumulative hours of use were 1.25 (0.55 to 2.88) and 1.77 (0.32 to 1.84), respectively. However, the contralateral users showed slightly lower risk than ipsilateral users.

CONCLUSIONS

Our results do not support the hypothesis that the use of mobile phones increases the risk of glioma; however, we found a non-significant increase in risk among ipsilateral users. These findings suggest further evaluation for glioma risk among long-term mobile phone users.

Mortality by neoplasia and cellular telephone base stations in the Belo Horizonte municipality, Minas Gerais state, Brazil

Pollution caused by the electromagnetic fields (EMFs) of radio frequencies (RF) generated by the telecommunication system is one of the greatest environmental problems of the twentieth century. The purpose of this research was to verify the existence of a spatial correlation between base station (BS) clusters and cases of deaths by neoplasia in the Belo Horizonte municipality, Minas Gerais state, Brazil, from 1996 to 2006 and to measure the human exposure levels to EMF where there is a major concentration of cellular telephone transmitter antennas. A descriptive spatial analysis of the BSs and the cases of death by neoplasia identified in the municipality was performed through an ecological-epidemiological approach, using georeferencing. The database employed in the survey was composed of three data banks: 1. death by neoplasia documented by the Health Municipal Department; 2. BSs documented in ANATEL ("Agência Nacional de Telecomunicações": 'Telecommunications National Agency'); and 3. census and demographic city population data obtained from official archives provided by IBGE ("Instituto Brasileiro de Geografia e Estatística": 'Brazilian Institute of Geography and Statistics'). The results show that approximately 856 BSs were installed through December 2006. Most (39.60%) of the BSs were located in the "Centro-Sul" ('Central-Southern') region of the municipality. Between 1996 and 2006, 7191 deaths by neoplasia occurred and within an area of 500 m from the BS, the mortality rate was 34.76 per 10,000 inhabitants. Outside of this area, a decrease in the number of deaths by neoplasia occurred. The greatest accumulated incidence was 5.83 per 1000 in the Central-Southern region and the lowest incidence was 2.05 per 1000 in the Barreiro region. During the environmental monitoring, the largest accumulated electric field measured was 12.4 V/m and the smallest was 0.4 V/m. The largest density power was 40.78 μW/cm(2), and the smallest was 0.04 μW/cm(2).

Risk of brain tumors from wireless phone use

The debate regarding the health effects of low-intensity electromagnetic radiation from sources such as power lines, base stations, and cell phones has recently been reignited. Wireless communication has dramatically influenced our lifestyle; its impact on human health has not been completely assessed. Widespread concern continues in the community about the deleterious effects of radiofrequency radiations on human tissues and the subsequent potential threat of carcinogenesis. Exposure to low-frequency electromagnetic field has been linked to a variety of adverse health outcomes. This article surveys the results of early cell phone studies, where exposure duration was too short to expect tumor genesis, and 2 sets of more recent studies with longer exposure duration: the Interphone studies and the Swedish studies led by Hardell.

The controversy about a possible relationship between mobile phone use and cancer

Over the last decade, mobile phone use increased to almost 100% prevalence in many countries. Evidence for potential health hazards accumulated in parallel by epidemiologic investigations has raised controversies about the appropriate interpretation and the degree of bias and confounding responsible for reduced or increased risk estimates. Overall, 33 epidemiologic studies were identified in the peer-reviewed literature, mostly (25) about brain tumors. Methodologic considerations revealed that three important conditions for epidemiologic studies to detect an increased risk are not met:no evidence-based exposure metric is available; the observed duration of mobile phone use is generally still too low; no evidence-based selection of end points among the grossly different types of neoplasias is possible because of lack of etiologic hypotheses. The overall evidence speaks in favor of an increased risk, but its magnitude cannot be assessed at present because of insufficient information on long-term use.

Mobile phone use and risk of tumors: a meta-analysis

PURPOSE

Case-control studies have reported inconsistent findings regarding the association between mobile phone use and tumor risk. We investigated these associations using a meta-analysis.

METHODS

We searched MEDLINE (PubMed), EMBASE, and the Cochrane Library in August 2008. Two evaluators independently reviewed and selected articles based on predetermined selection criteria.

RESULTS

Of 465 articles meeting our initial criteria, 23 case-control studies, which involved 37,916 participants (12,344 patient cases and 25,572 controls), were included in the final analyses. Compared with never or rarely having used a mobile phone, the odds ratio for overall use was 0.98 for malignant and benign tumors (95% CI, 0.89 to 1.07) in a random-effects meta-analysis of all 23 studies. However, a significant positive association (harmful effect) was observed in a random-effects meta-analysis of eight studies using blinding, whereas a significant negative association (protective effect) was observed in a fixed-effects meta-analysis of 15 studies not using blinding. Mobile phone use of 10 years or longer was associated with a risk of tumors in 13 studies reporting this association (odds ratio = 1.18; 95% CI, 1.04 to 1.34). Further, these findings were also observed in the subgroup analyses by methodologic quality of study. Blinding and methodologic quality of study were strongly associated with the research group.

CONCLUSION

The current study found that there is possible evidence linking mobile phone use to an increased risk of tumors from a meta-analysis of low-biased case-control studies. Prospective cohort studies providing a higher level of evidence are needed.

Uveal and Conjunctival Malignant Melanoma in Denmark, 1943–97: Incidence and Validation Study

PURPOSE

To study the incidence of malignant melanoma in the ocular region in Denmark during the period 1943-97.

METHODS

The patients were mainly identified through the Danish Cancer Registry. Age-period-cohort modelling of the incidence rates was done based on age at diagnosis, calendar period and birth cohort in 5-year groups and for each gender.

RESULTS

The age-standardized incidence of malignant melanoma in the ocular region was 0.78 for men (N = 1327) and 0.65 for women (N = 1242) per 100,000 person-years. Calendar period and birth cohort had no effect on the incidence in the ocular region or in the topography subgroups choroid/ciliary body and conjunctiva. However, the incidence increased with birth cohort for iris melanomas.

CONCLUSIONS

The incidence of malignant melanoma in the ocular region was stable in contrast to a major increase in cutaneous melanoma in Denmark during the period 1943-97. The incidence of iris melanomas increased substantially, whereas the rate was stable for choroid/ciliary body and conjunctival melanomas.

Phenotypical characteristics, lifestyle, social class and uveal melanoma

PURPOSE

To investigate potential risk factors of uveal melanoma, including phenotypical characteristics, eye burns, social class, smoking and alcohol consumption.

METHODS

A hospital-based and population-based case-control study of uveal melanoma was carried out from 1995 through 1998 and the results pooled. A total of 118 patients (59 men and 59 women) with uveal melanoma and 475 controls matching on sex, age and study regions were interviewed. Conditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

There was an elevated risk for blue or grey iris color (OR = 3.0, 95% CI 1.5-6.0). Red or blond hair color at age 20 was slightly associated with an increased risk for uveal melanoma (OR = 1.5, 95% CI 0.9-2.4). There was no elevated risk for a history of eye burns (OR = 1.1, 95% CI 0.5-2.4).

CONCLUSIONS

Among the potential risk factors studied, only the phenotypical characteristics showed an association with the risk of uveal melanoma.

Public health implications of wireless technologies

Global exposures to emerging wireless technologies from applications including mobile phones, cordless phones, DECT phones, WI-FI, WLAN, WiMAX, wireless internet, baby monitors, and others may present serious public health consequences. Evidence supporting a public health risk is documented in the BioInitiative Report. New, biologically based public exposure standards for chronic exposure to low-intensity exposures are warranted. Existing safety standards are obsolete because they are based solely on thermal effects from acute exposures. The rapidly expanding development of new wireless technologies and the long latency for the development of such serious diseases as brain cancers means that failure to take immediate action to reduce risks may result in an epidemic of potentially fatal diseases in the future. Regardless of whether or not the associations are causal, the strengths of the associations are sufficiently strong that in the opinion of the authors, taking action to reduce exposures is imperative, especially for the fetus and children. Such action is fully compatible with the precautionary principle, as enunciated by the Rio Declaration, the European Constitution Principle on Health (Section 3.1) and the European Union Treaties Article 174.

The controversy about a possible relationship between mobile phone use and cancer

OBJECTIVE

During the last decade, mobile phone use increased to almost 100% prevalence in many countries of the world. Evidence for potential health hazards accumulated in parallel by epidemiologic investigations has raised controversies about the appropriate interpretation and the degree of bias and confounding responsible for reduced or increased risk estimates.

DATA SOURCES

Overall, I identified 33 epidemiologic studies in the peer-reviewed literature, most of which (25) were about brain tumors. Two groups have collected data for >or=10 years of mobile phone use: Hardell and colleagues from Sweden and the Interphone group, an international consortium from 13 countries coordinated by the International Agency for Research on Cancer.

DATA SYNTHESIS

Combined odds ratios (95% confidence intervals) from these studies for glioma, acoustic neuroma, and meningioma were 1.5 (1.2-1.8); 1.3 (0.95-1.9); and 1.1 (0.8-1.4), respectively.

CONCLUSIONS

Methodologic considerations revealed that three important conditions for epidemiologic studies to detect an increased risk are not met: a ) no evidence-based exposure metric is available; b) the observed duration of mobile phone use is generally still too low; c) no evidence-based selection of end points among the grossly different types of neoplasias is possible because of lack of etiologic hypotheses. Concerning risk estimates, selection bias, misclassification bias, and effects of the disease on mobile phone use could have reduced estimates, and recall bias may have led to spuriously increased risks. The overall evidence speaks in favor of an increased risk, but its magnitude cannot be assessed at present because of insufficient information on long-term use.

Mobile phone use and risk of uveal melanoma: results of the risk factors for uveal melanoma case-control study

We recently reported an increased risk of uveal melanoma among mobile phone users. Here, we present the results of a case–control study that assessed the association between mobile phone use and risk of uveal melanoma. We recruited 459 uveal melanoma case patients at the University of Duisburg-Essen and matched 455 case patients with 827 population control subjects, 133 with 180 ophthalmologist control subjects, and 187 with 187 sibling control subjects. We used a questionnaire to assess mobile phone use and estimated odds ratios (ORs) and 95% confidence intervals (95% CIs) of risk for uveal melanoma using conditional logistic regression. Risk of uveal melanoma was not associated with regular mobile phone use (OR = 0.7, 95% CI = 0.5 to 1.0 vs population control subjects; OR = 1.1, 95% CI = 0.6 to 2.3 vs ophthalmologist control subjects; and OR = 1.2, 95% CI = 0.5 to 2.6 vs sibling control subjects), and we observed no trend for cumulative measures of exposure. We did not corroborate our previous results that showed an increased risk of uveal melanoma among regular mobile phone users.

[Epidemiologic challenges in rare diseases]

Rare diseases, often called "orphan diseases", are a special challenge for epidemiologic research. Apart from the mere logistic effort for sample collection, there are considerable implications in statistical methodology. Usually one will not find enough cases of an orphan disease in a random sample from the population at risk. Furthermore, random error plays a more important role for decreasing probability of disease. Critical issues related to total population sampling, active and passive surveillance and capture-recapture methods are discussed. Challenges in risk factor research and related to therapeutic or preventive trials are presented. Examples from epidemiologic practice are given.

Recent advances in research on radiofrequency fields and health: 2001-2003

The widespread use of wireless telecommunications devices, particularly mobile phones, has resulted in increased human exposure to radiofrequency (RF) fields. Although national and international agencies have established safety guidelines for exposure to RF fields, concerns remain about the potential for adverse health outcomes to occur in relation to RF field exposure. The extensive literature on RF fields and health has been reviewed by a number of authorities, including the Royal Society of Canada (1999), the European Commission's Scientific Committee on Toxicity, Ecotoxicity, and the Environment (CSTEE, 2001), the British Medical Association (2001), the Swedish Radiation Protection Authority (Boice & McLaughlin, 2002), and the Health Council of The Netherlands (2002). This report provides an update on recent research results on the potential health risks of RF fields since the publication of the Royal Society of Canada report in 1999 (See Krewski et al., 2001a) and our previous 2001 update (Krewski et al., 2001b), covering the period 2001-2003. The present report examines new data on dosimetry and exposure assessment, biological effects such as enzyme induction, and toxicological effects, including genotoxicity, carcinogenicity, and testicular and reproductive outcomes. Epidemiological studies of mobile phone users and occupationally exposed populations are examined, along with human and animal studies of neurological and behavioral effects. All of the authoritative reviews completed within the last 2 yr have concluded that there is no clear evidence of adverse health effects associated with RF fields. However, following a recent review of nine epidemiological studies of mobile phones and cancer, Kundi et al. (2004) concluded that the possibility of an enhanced cancer risk cannot be excluded. These same reviews support the need for further research to clarify the possible associations between RF fields and adverse health outcomes that have appeared in some reports. The results of the ongoing World Health Organization (WHO) study of mobile phones will provide important new information in this regard.

Exposure-measurement error is frequently ignored when interpreting epidemiologic study results

INTRODUCTION

One important source of error in study results is error in measuring exposures. When interpreting study results, one should consider the impact that exposure-measurement error (EME) might have had on study results.

METHODS

To assess how often this consideration is made and the form it takes, journal articles were randomly sampled from original articles appearing in the American Journal of Epidemiology and Epidemiology in 2001, and the International Journal of Epidemiology between December 2000 and October 2001.

RESULTS

Twenty-two (39%) of the 57 articles surveyed mentioned nothing about EME. Of the 35 articles that mentioned something about EME, 16 articles described qualitatively the effect EME could have had on study results. Only one study quantified the impact of EME on study results; the investigators used a sensitivity analysis. Few authors discussed the measurement error in their study in any detail.

CONCLUSIONS

Overall, the potential impact of EME on error in epidemiologic study results appears to be ignored frequently in practice.

Monitoring the effects of mobile phone use on the brain by proton magnetic resonance spectroscopy

PURPOSE

To determine whether extensive use of mobile phones affects brain metabolites detectable by proton magnetic resonance spectroscopy (1H MRS).

MATERIALS AND METHODS

Twenty-one extensive mobile phone users (average use = 5.5 +/- 2.2 years at 2.4 +/- 1.1 hours/day) and 15 control subjects were recruited and submitted to a 1H MRS brain examination at 1.5 Tesla. Data were recorded in the most exposed right temporal and pontobulbar areas as well as in the contralateral left temporal area. The ratios of N-acetylaspartate (NAA), choline (Cho) and myo-inositol (mI) to creatine/phosphocreatine (Cr) were measured.

RESULTS

No statistically significant changes in the NAA/Cr, Cho/Cr and mI/Cr ratios were measured between mobile phone users and control subjects and between the exposed and contralateral temporal areas.

CONCLUSION

These results indicate that extensive exposition to mobile phone radiation does not cause MRS-detectable brain metabolic changes.

Cellular Telephone Use and Cancer Risk: Update of a Nationwide Danish Cohort

BACKGROUND

The widespread use of cellular telephones has heightened concerns about possible adverse health effects. The objective of this study was to investigate cancer risk among Danish cellular telephone users who were followed for up to 21 years.

METHODS

This study is an extended follow-up of a large nationwide cohort of 420,095 persons whose first cellular telephone subscription was between 1982 and 1995 and who were followed through 2002 for cancer incidence. Standardized incidence ratios (SIRs) were calculated by dividing the number of observed cancer cases in the cohort by the number expected in the Danish population.

RESULTS

A total of 14,249 cancers were observed (SIR = 0.95; 95% confidence interval [CI] = 0.93 to 0.97) for men and women combined. Cellular telephone use was not associated with increased risk for brain tumors (SIR = 0.97), acoustic neuromas (SIR = 0.73), salivary gland tumors (SIR = 0.77), eye tumors (SIR = 0.96), or leukemias (SIR = 1.00). Among long-term subscribers of 10 years or more, cellular telephone use was not associated with increased risk for brain tumors (SIR = 0.66, 95% CI = 0.44 to 0.95), and there was no trend with time since first subscription. The risk for smoking-related cancers was decreased among men (SIR = 0.88, 95% CI = 0.86 to 0.91) but increased among women (SIR = 1.11, 95% CI = 1.02 to 1.21). Additional data on income and smoking prevalence, primarily among men, indicated that cellular telephone users who started subscriptions in the mid-1980s appeared to have a higher income and to smoke less than the general population.

CONCLUSIONS

We found no evidence for an association between tumor risk and cellular telephone use among either short-term or long-term users. Moreover, the narrow confidence intervals provide evidence that any large association of risk of cancer and cellular telephone use can be excluded.

The effects of recall errors and of selection bias in epidemiologic studies of mobile phone use and cancer risk

This paper examines the effects of systematic and random errors in recall and of selection bias in case-control studies of mobile phone use and cancer. These sensitivity analyses are based on Monte-Carlo computer simulations and were carried out within the INTERPHONE Study, an international collaborative case-control study in 13 countries. Recall error scenarios simulated plausible values of random and systematic, non-differential and differential recall errors in amount of mobile phone use reported by study subjects. Plausible values for the recall error were obtained from validation studies. Selection bias scenarios assumed varying selection probabilities for cases and controls, mobile phone users, and non-users. Where possible these selection probabilities were based on existing information from non-respondents in INTERPHONE. Simulations used exposure distributions based on existing INTERPHONE data and assumed varying levels of the true risk of brain cancer related to mobile phone use. Results suggest that random recall errors of plausible levels can lead to a large underestimation in the risk of brain cancer associated with mobile phone use. Random errors were found to have larger impact than plausible systematic errors. Differential errors in recall had very little additional impact in the presence of large random errors. Selection bias resulting from underselection of unexposed controls led to J-shaped exposure-response patterns, with risk apparently decreasing at low to moderate exposure levels. The present results, in conjunction with those of the validation studies conducted within the INTERPHONE study, will play an important role in the interpretation of existing and future case-control studies of mobile phone use and cancer risk, including the INTERPHONE study.

How dangerous are mobile phones, transmission masts, and electricity pylons?

Electrical power and mobile communications deliver enormous benefit to society, but there are concerns whether the electric and magnetic field (EMF) emissions associated with the delivery of this benefit are linked to cancer or other health hazards. This article reviews the strength of the available epidemiological and laboratory evidence and notes that this falls short of what is normally required to establish a causal link. However, because of scientific uncertainty a cautious approach is often advocated, but here, too, there may be a tendency to judge these risks more harshly than those in other areas with similar strength of evidence.

Population-based incidence estimates of uveal melanoma in Germany. Supplementing cancer registry data by case–control data

Valid incidence rates of uveal melanoma (UM) from German population-based cancer registries are currently not available due to under-reporting. We conducted two case-control studies on UM at a reference centre for eye tumours and show the influence on population-based incidences of UM when data from case-control studies are linked with a cancer registry. The first case-control study (1996-1998) recruited 13 UM cases aged 35-74 years and the second case-control study (2002-2003) recruited 20 UM cases aged 20-74 residing within the population covered by the Münster Cancer Registry. After record linkage, age-truncated and standardized (World Standard Population) incidences with and without the record linkage were compared. Incidence rates based on routine cancer registration increased by a factor of 1.7 (1996-1998, age group 35-74 years) and 3.7 (2002-2003, age group 20-74 years) after record linkage with the case-control data. The supplemented age-standardized incidence of UM is 8.6 per million (20-74 years, 2002-2003) compared with the unsupplemented incidence of 2.3 per million. UM unknown to the registry were less often morphologically verified than those known to the registry. Cancer registries relying on pathology reports underestimate UM incidences if eye-preserving treatments are introduced. Close co-operation between cancer referral centres and cancer registries can substantially improve the completeness of registration.

Free radical release and HSP70 expression in two human immune-relevant cell lines after exposure to 1800 MHz radiofrequency radiation

The goal of this study was to investigate whether radiofrequency (RF) electromagnetic-field (EMF) exposure at 1800 MHz causes production of free radicals and/or expression of heat-shock proteins (HSP70) in human immune-relevant cell systems. Human Mono Mac 6 and K562 cells were used to examine free radical release after exposure to incubator control, sham, RF EMFs, PMA, LPS, heat (40 degrees C) or co-exposure conditions. Several signals were used: continuous-wave, several typical modulations of the Global System for Mobile Communications (GSM): GSM-non DTX (speaking only), GSM-DTX (hearing only), GSM-Talk (34% speaking and 66% hearing) at specific absorption rates (SARs) of 0.5, 1.0, 1.5 and 2.0 W/kg. Heat and PMA treatment induced a significant increase in superoxide radical anions and in ROS production in the Mono Mac 6 cells when compared to sham and/or incubator conditions. No significant differences in free radical production were detected after RF EMF exposure or in the respective controls, and no additional effects on superoxide radical anion production were detected after co-exposure to RF EMFs+PMA or RF EMFs+LPS. The GSM-DTX signal at 2 W/kg produced a significant difference in free radical production when the data were compared to sham because of the decreasing sham value. This difference disappeared when data were compared to the incubator controls. To determine the involvement of heat-shock proteins as a possible inhibitor of free radical production, we investigated the HSP70 expression level after different RF EMF exposures; no significant effects were detected.

Electromagnetic fields affect transcript levels of apoptosis-related genes in embryonic stem cell-derived neural progenitor cells

Mouse embryonic stem (ES) cells were used as an experimental model to study the effects of electromagnetic fields (EMF). ES-derived nestin-positive neural progenitor cells were exposed to extremely low frequency EMF simulating power line magnetic fields at 50 Hz (ELF-EMF) and to radiofrequency EMF simulating the Global System for Mobile Communication (GSM) signals at 1.71 GHz (RF-EMF). Following EMF exposure, cells were analyzed for transcript levels of cell cycle regulatory, apoptosis-related, and neural-specific genes and proteins; changes in proliferation; apoptosis; and cytogenetic effects. Quantitative RT-PCR analysis revealed that ELF-EMF exposure to ES-derived neural cells significantly affected transcript levels of the apoptosis-related bcl-2, bax, and cell cycle regulatory "growth arrest DNA damage inducible" GADD45 genes, whereas mRNA levels of neural-specific genes were not affected. RF-EMF exposure of neural progenitor cells resulted in down-regulation of neural-specific Nurr1 and in up-regulation of bax and GADD45 mRNA levels. Short-term RF-EMF exposure for 6 h, but not for 48 h, resulted in a low and transient increase of DNA double-strand breaks. No effects of ELF- and RF-EMF on mitochondrial function, nuclear apoptosis, cell proliferation, and chromosomal alterations were observed. We may conclude that EMF exposure of ES-derived neural progenitor cells transiently affects the transcript level of genes related to apoptosis and cell cycle control. However, these responses are not associated with detectable changes of cell physiology, suggesting compensatory mechanisms at the translational and posttranslational level.

Mobile phones and health: a literature overview

The rapidly evolving mobile phone technology raised public concern about the possibility of associated adverse health effects. The current body of evidence is summarized addressing epidemiological studies, studies investigating adverse biological effects, other biological effects, basic mechanisms and indirect effects. Currently, the balance of evidence from epidemiological studies suggests that there is no association between mobile phone radiation and cancer. This finding is consistent with experimental results. There is some evidence for biological effects, which, however, are not necessarily hazardous for humans. No basic mechanisms of biological effects have been consistently identified yet. Using a mobile phone while driving a car is significantly associated with a higher risk of vehicle collisions, independently of the use of hands-free kits. Medical equipment or implanted pacemakers may be affected by mobile phone radiation under very specific conditions. Current studies, however are affected by several limitations and do not generally exclude any increased health risk. Further high-quality research is therefore necessary. Furthermore, it is important that the results of scientific research are communicated to the public in a transparent and differentiated way.

Intermittent and chronic ultraviolet light exposure and uveal melanoma: a meta-analysis

OBJECTIVE

To examine the association between ultraviolet light exposure and uveal melanoma.

DESIGN

Meta-analysis.

METHODS

A review of 133 published reports on risk factors for uveal melanoma revealed 12 studies that provided sufficient information to calculate odds ratios (ORs) and standard errors for ultraviolet light exposure factors. Data from these studies were extracted and categorized into intermittent ultraviolet exposure factors (welding, outdoor leisure, photokeratitis) and chronic ultraviolet exposure factors (occupational sunlight exposure, birth latitude, lifetime ultraviolet exposure index). Summary statistics were calculated for all risk factors reported by > or =4 independent studies.

MAIN EXPOSURE MEASURES

Welding, outdoor leisure, photokeratitis, occupational sunlight exposure, birth latitude, and lifetime ultraviolet exposure index.

RESULTS

For intermittent ultraviolet exposure, welding was found to be a significant risk factor (5 studies, 1137 cases; OR, 2.05 [95% confidence interval [CI], 1.20-3.51]). Outdoor leisure was found to be nonsignificant (4 studies, 1332 cases; OR, 0.86 [95% CI, 0.71-1.04]). Photokeratitis conferred susceptibility in 3 reports studying this variable, but there were too few studies to validate meta-analyses. For chronic ultraviolet exposure, meta-analysis found occupational sunlight exposure to be a borderline nonsignificant risk factor for development of uveal melanoma (4 studies, 572 cases; OR, 1.37 [95% CI, 0.96-1.96]). Latitude of birth was found to be nonsignificant (5 studies, 1765 cases; OR, 1.08 [95% CI, 0.67-1.74]).

CONCLUSION

This meta-analysis yielded inconsistent results associating ultraviolet light with development of uveal melanoma. There was evidence implicating welding as a possible risk factor for uveal melanoma.

EMF and health

Electric and magnetic fields are ubiquitous in the modern society, and concerns have been expressed regarding possible adverse effects of these exposures. This review covers epidemiologic research on health effects of exposures to static, extremely low-frequency (ELF), and radio frequency (RF) fields. Research on ELF fields has been performed for more than two decades, and the methodology and quality of studies have improved over time. Studies have consistently shown increased risk for childhood leukemia associated with ELF magnetic fields, whereas ELF fields most likely are not a risk factor for breast cancer and cardiovascular disease. There are still inadequate data for other outcomes. More recently, focus has shifted toward RF exposures from mobile telephony. There are no persuasive data suggesting a health risk, but this research field is still immature with regard to the quantity and quality of available data. This technology is constantly changing and there is a need for continued research on this issue. Almost no epidemiologic data are available for static fields.

Cellular telephone use among primary school children in Germany

BACKGROUND

There is some concern about potential health risks of cellular telephone use to children. We assessed data on how many children own a cellular telephone and on how often they use it in a population-based sample.

METHODS

We carried out a cross-sectional study among children in their fourth elementary school year, with a median-age of 10 years. The study was carried out in Mainz (Germany), a city with about 200,000 inhabitants. The study base comprised all 37 primary schools in Mainz and near surroundings. Altogether, 1933 children from 34 primary schools took part in the survey (participation rate of 87.8%).

RESULTS

Roughly a third of all children (n = 671, 34.7%) reported to own a cellular telephone. Overall, 119 (6.2%) children used a cellular telephone for making calls at least once a day, 123 (6.4%) used it several times a week and 876 (45.3%) children used it only once in a while. The remaining 805 (41.6%) children had never used a cellular telephone. The probability of owning a cellular telephone among children was associated with older age, being male, having no siblings, giving full particulars to height and weight, more time spent watching TV and playing computer games, being picked up by their parents from school by car (instead of walking or cycling) and going to bed late. The proportion of cellular telephone owners was somewhat higher in classes with more children from socially disadvantaged families.

CONCLUSIONS

Our study shows that both ownership of a cellular telephone as well as the regular use of it are already quite frequent among children in the fourth grade of primary school. With regard to potential long-term effects, we recommend follow-up studies with children.

Occupational risks for uveal melanoma results from a case-control study in nine European countries

OBJECTIVE

Uveal melanoma is a rare disease with poor prognosis and largely unknown etiology. We studied potential occupational risk factors.

METHODS

A population based case-control study was undertaken during 1995-1997 in nine European countries using population and colon cancer controls with personal interviews. Occupational exposure to sunlight and artificial UV radiation was assessed with a job exposure matrix. In total, 320 uveal melanoma cases were eligible at pathology review, and 292 cases were interviewed, participation 91%. Out of 3357 population controls, 2062 were interviewed, 61%, and out of 1272 cancer controls 1094 were interviewed, 86%.

RESULTS

Using population controls, occupational exposure to sunlight was not associated with an increased risk (RR=1.24, 95% CI=0.88-1.74), while an excess risk found with use of colon cancer controls was attributed to confounding factors. An excess risk in welders was restricted to the French part of the data. Cooks, RR=2.40; cleaners, RR 2.15; and laundry workers, RR=3.14, were at increased risk of uveal melanoma.

CONCLUSION

Our study does overall not support an association between occupational sunlight exposure and risk of uveal melanoma. The finding of an excess risk of eye melanoma in cooks in several European countries is intriguing.

International uveal melanoma incidence trends in view of a decreasing proportion of morphological verification

The introduction of eye-preserving therapies for uveal melanoma in the 1970s complicates time trend analyses of the uveal melanoma incidence because the proportion of morphologically verified uveal melanoma has been decreasing over the decades. We carried out incidence trend analyses, based on data from internationally accredited population-based cancer registries throughout the world that take missing data on topography, morphology and basis of diagnosis of eye tumours into account. We selected incidence data of cancer registries that were included in Cancer Incidence In 5 Continents, Volumes VI-VIII covering a registration period of at least 15 years (usually 1983 to 1997) and classified each eye cancer as morphologically verified uveal melanoma, clinically diagnosed uveal melanoma, uveal melanoma identified as DCO case (Death certificate only), possibly uveal melanoma, other eye tumour or unclassifiable eye tumour and calculated age-standardized incidence rates by 3-year calendar periods using the World Standard Population as the reference. The uveal melanoma incidence decline in the United States SEER Caucasian population is due mainly to an incidence decline in the early registration period (from 1974-76 to 1986-88). The data from France and Italy suggest a recent increase in incidence. Uveal melanoma diagnosed clinically increasingly contribute to the overall uveal melanoma incidence over time. Combining all registries, the proportion of morphologically verified uveal melanoma decreased from 82% in 1983-87 to 75% in 1993-97. Uveal melanoma incidence rates remained quite stable during the period 1983-97. The interpretation of uveal melanoma incidence trends is complicated by missing data on topography within the eye, morphology and basis of diagnosis.

Epidemiology of health effects of radiofrequency exposure

We have undertaken a comprehensive review of epidemiologic studies about the effects of radiofrequency fields (RFs) on human health in order to summarize the current state of knowledge, explain the methodologic issues that are involved, and aid in the planning of future studies. There have been a large number of occupational studies over several decades, particularly on cancer, cardiovascular disease, adverse reproductive outcome, and cataract, in relation to RF exposure. More recently, there have been studies of residential exposure, mainly from radio and television transmitters, and especially focusing on leukemia. There have also been studies of mobile telephone users, particularly on brain tumors and less often on other cancers and on symptoms. Results of these studies to date give no consistent or convincing evidence of a causal relation between RF exposure and any adverse health effect. On the other hand, the studies have too many deficiencies to rule out an association. A key concern across all studies is the quality of assessment of RF exposure. Despite the ubiquity of new technologies using RFs, little is known about population exposure from RF sources and even less about the relative importance of different sources. Other cautions are that mobile phone studies to date have been able to address only relatively short lag periods, that almost no data are available on the consequences of childhood exposure, and that published data largely concentrate on a small number of outcomes, especially brain tumor and leukemia.

No effects of GSM-modulated 900 MHz electromagnetic fields on survival rate and spontaneous development of lymphoma in female AKR/J mice

Background

Several reports indicated that non-thermal electromagnetic radiation such as from mobile phones and base stations may promote cancer. Therefore, it was investigated experimentally, whether 900 MHz electromagnetic field exposure influences lymphoma development in a mouse strain that is genetically predisposed to this disease. The AKR/J mice genome carries the AK-virus, which leads within one year to spontaneous development of thymic lymphoblastic lymphoma.

Methods

320 unrestrained female mice were sham-exposed or exposed (each n = 160 animals) to GSM like 900 MHz electromagnetic fields for 24 hours per day, 7 days per week, at an average whole body specific absorption rate (SAR) value of 0.4 W/kg. Animals were visually checked daily and were weighed and palpated weekly. Starting with an age of 6 months, blood samples were taken monthly from the tail. Animals with signs of disease or with an age of about 46 weeks were sacrificed and a gross necropsy was performed.

Results

Electromagnetic field exposure had a significant effect on body weight gain, with higher values in exposed than in sham-exposed animals. However, survival rate and lymphoma incidence did not differ between exposed and sham-exposed mice.

Conclusion

These data do not support the hypothesis that exposure to 900 MHz electromagnetic fields is a significant risk factor for developing lymphoma in a genetically predisposed species, even at a relatively high exposure level.