Cognitive performance measures in bioelectromagnetic research--critical evaluation and recommendations

Electric and magnetic field pollution in near substations and investigation of anxiety and depressive effects on adult individuals living in this area

Exposure to electromagnetic fields causes a variety of health problems in living systems. We investigated EMF pollution in Şanlıurfa city center and also investigated anxiety-depression symptoms in individuals (18-40 years old) exposed to this pollution. For this purpose, electric field and magnetic field measurements were taken at Electricity Distribution Center and 44 substations (for each transformer), at 0 points, 1 meter away, 2 meters away and the house/office closest to the transformer. The experimental group was individuals living in electricity distribution center residences and individuals living near transformers (n = 55). The control group was selected from individuals who lived outside the city center of Şanlıurfa, did not have transformers or high transmission lines near their homes, and did not have any chronic diseases that could cause stress (n = 50). Anxiety and depression symptoms of the groups were measured using the Beck Anxiety Inventory Scale (BAI) and Beck Depression Inventory Scale (BDI). The relationship between EMF pollution and anxiety-depression was evaluated statistically. Maximum MF and EF values were recorded as 0.22 mT and 65.9 kV/m, respectively. All measured MF values were below standards, but EF values were above standards at some points. In conclusion, there is no statistically convincing evidence of a relationship between EMF exposure and anxiety-depression (p > 0.05). This result shows that there may be more meaningful results in places with higher EMF levels. We interpreted the fact that exposure to electromagnetic fields does not cause anxiety and depression in individuals, as the measured values are below the limit values.

The effects of radiofrequency exposure on cognition: A systematic review and meta-analysis of human observational studies

BACKGROUND

We aimed to assess evidence of long-term effects of exposure to radiofrequency (RF) electromagnetic fields (EMF) on indicators of cognition, including domains of learning and memory, executive function, complex attention, language, perceptual motor ability and social cognition, and of an exposure-response relationship between RF-EMF and cognition.

METHODS

We searched PubMed, Embase, PsycInfo and the EMF-Portal on September 30, 2022 without limiting by date or language of publication. We included cohort or case-control studies that evaluated the effects of RF exposure on cognitive function in one or more of the cognitive domains. Studies were rated for risk of bias using the OHAT tool and synthesised using fixed effects meta-analysis. We assessed the certainty of the evidence using the GRADE approach and considered modification by OHAT for assessing evidence of exposures.

RESULTS

We included 5 studies that reported analyses of data from 4 cohorts with 4639 participants consisting of 2808 adults and 1831 children across three countries (Australia, Singapore and Switzerland) conducted between 2006 and 2017. The main source of RF-EMF exposure was mobile (cell) phone use measured as calls per week or minutes per day. For mobile phone use in children, two studies (615 participants) that compared an increase in mobile phone use to a decrease or no change were included in meta-analyses. Learning and memory. There was little effect on accuracy (mean difference, MD -0.03; 95% CI -0.07 to 0.02) or response time (MD -0.01; 95% CI -0.04 to 0.02) on the one-back memory task; and accuracy (MD -0.02; 95%CI -0.04 to 0.00) or response time (MD -0.01; 95%CI -0.04 to 0.03) on the one card learning task (low certainty evidence for all outcomes). Executive function. There was little to no effect on the Stroop test for the time ratio ((B-A)/A) response (MD 0.02; 95% CI -0.01 to 0.04, very low certainty) or the time ratio ((D-C)/C) response (MD 0.00; 95% CI -0.06 to 0.05, very low certainty), with both tests measuring susceptibility to interference effects. Complex attention. There was little to no effect on detection task accuracy (MD 0.02; 95% CI -0.04 to 0.08), or response time (MD 0.02;95% CI 0.01 to 0.03), and little to no effect on identification task accuracy (MD 0.00; 95% CI -0.04 to 0.05) or response time (MD 0.00;95% CI -0.01 to 0.02) (low certainty evidence for all outcomes). No other cognitive domains were investigated in children. A single study among elderly people provided very low certainty evidence that more frequent mobile phone use may have little to no effect on the odds of a decline in global cognitive function (odds ratio, OR 0.81; 95% CI 0.42 to 1.58, 649 participants) or a decline in executive function (OR 1.07; 95% CI 0.37 to 3.05, 146 participants), and may lead to a small, probably unimportant, reduction in the odds of a decline in complex attention (OR 0.67;95%CI 0.27 to 1.68, 159 participants) and a decline in learning and memory (OR 0.75; 95% CI 0.29 to 1.99, 159 participants). An exposure-response relationship was not identified for any of the cognitive outcomes.

DISCUSSION

This systematic review and meta-analysis found only a few studies that provided very low to low certainty evidence of little to no association between RF-EMF exposure and learning and memory, executive function and complex attention. None of the studies among children reported on global cognitive function or other domains of cognition. Only one study reported a lack of an effect for all domains in elderly persons but this was of very low certainty evidence. Further studies are needed to address all types of populations, exposures and cognitive outcomes, particularly studies investigating environmental and occupational exposure in adults. Future studies also need to address uncertainties in the assessment of exposure and standardise testing of specific domains of cognitive function to enable synthesis across studies and increase the certainty of the evidence.

OTHER

This review was partially funded by the WHO radioprotection programme and prospectively registered on PROSPERO CRD42021257548.

Cardiac Cell Exposure to Electromagnetic Fields: Focus on Oxdative Stress and Apoptosis

Exposure to electromagnetic fields (EMFs) is a sensitive research topic. Despite extensive research, to date there is no evidence to conclude that exposure to EMFs influences the cardiovascular system. In the present study, we examined whether 915 MHz EMF exposure affects myocardial antioxidative and apoptotic status in vitro and in vivo. No statistically significant difference in the apoptotic cell profile and antioxidant capacity was observed between controls and short-term EMF-exposed mouse cardiomyocytes and H9C2 cardiomyoblasts. Compared with sham-exposed controls, mice subjected to a 915 MHz EMF for 48 h and 72 h had no significant effect on structural tissue integrity and myocardial expression of apoptosis and antioxidant genes. Therefore, these results indicate that short-term exposure to EMF in cardiac cells and tissues did not translate into a significant effect on the myocardial antioxidant defense system and apoptotic cell death.

The effect of long-term radiofrequency exposure on cognition in human observational studies: A protocol for a systematic review

BACKGROUND

The long term effects of exposure to radiofrequency (RF) electromagnetic fields (EMF) for frequencies from 100 kHz to 300 GHz on cognitive performance are best assessed using observational studies. In recent years, the use of mobile (cell) phones has been the main source of RF EMF exposure to the brain, although other sources of exposure may be significant. Cognitive function includes various mental and psychological abilities, which can be measured in a range of domains, such as learning, memory, reasoning, problem solving, decision making and attention. Although effects on cognitive function may be most evident later in life, in the experimental setting acute and immediate effects can only be studied. Observational studies are needed when effects are observed after months or years following short or long-term exposure. The importance of the effects of exposure on children has also been recently identified.

OBJECTIVES

To assess the long-term effects of RF EMF local and whole-body exposure compared to no or a lower level of exposure on indicators of cognition, including complex attention, executive function, learning and memory, perceptual motor ability and social cognition, but excluding cognitive effects caused by neurodegenerative diseases or neurodevelopmental disorders, and to assess if there is evidence of a dose response relationship.

STUDY ELIGIBILITY AND CRITERIA

We will include observational studies that have evaluated cognitive effects of RF energy including a comparator group with a different level of exposure. Studies must report at least one validated measure of cognitive function, including global or domain specific measures, or cognitive impairment, with a minimum follow-up of 6 months. Cohort or case-control studies published in the peer review literature in any language are eligible. We will exclude cross-sectional studies and any that only report brain structure or biomarkers.

STUDY APPRAISAL AND SYNTHESIS METHOD

We will conduct searches of PubMed, Embase, PsycINFO and the EMF-Portal. At least two authors will independently screen the titles/abstracts of all records, with any conflicts resolved by a third reviewer. Full-text screening will also be conducted independently by two authors with conflicts resolved by consensus. Data will be extracted from the studies included, such as identifiers and characteristics of the study design, exposure and comparator groups, participants, outcomes assessed and results. Risk of bias will be assessed with the Office of Health Assessment and Translation (OHAT) tool. We will conduct a meta-analysis of similar studies with a random effects model in STATA or similar software, if two or more studies are available for a given exposure-outcome combination. Confidence in the body evidence will be judged using GRADE methods as adapted by OHAT for reviews of environmental exposures.

The effect of radiofrequency electromagnetic fields (RF-EMF) on biomarkers of oxidative stress in vivo and in vitro: A protocol for a systematic review

BACKGROUND

Oxidative stress is conjectured to be related to many diseases. Furthermore, it is hypothesized that radiofrequency fields may induce oxidative stress in various cell types and thereby compromise human and animal health. This systematic review (SR) aims to summarize and evaluate the literature related to this hypothesis.

OBJECTIVES

The main objective of this SR is to evaluate the associations between the exposure to radiofrequency electromagnetic fields and oxidative stress in experimental models (in vivo and in vitro).

METHODS

The SR framework has been developed following the guidelines established in the WHO Handbook for Guideline Development and the Handbook for Conducting a Literature-Based Health Assessment). We will include controlled in vivo and in vitro laboratory studies that assess the effects of an exposure to RF-EMF on valid markers for oxidative stress compared to no or sham exposure. The protocol is registered in PROSPERO. We will search the following databases: PubMed, Embase, Web of Science Core Collection, Scopus, and the EMF-Portal. The reference lists of included studies and retrieved review articles will also be manually searched.

STUDY APPRAISAL AND SYNTHESIS METHOD

Data will be extracted according to a pre-defined set of forms developed in the DistillerSR online software and synthesized in a meta-analysis when studies are judged sufficiently similar to be combined. If a meta-analysis is not possible, we will describe the effects of the exposure in a narrative way.

RISK OF BIAS

The risk of bias will be assessed with the NTP/OHAT risk of bias rating tool for human and animal studies. We will use GRADE to assess the certainty of the conclusions (high, moderate, low, or inadequate) regarding the association between radiofrequency electromagnetic fields and oxidative stress.

FUNDING

This work was funded by the World Health Organization (WHO).

REGISTRATION

The protocol was registered on the PROSPERO webpage on July 8, 2021.

The effect of exposure to radiofrequency electromagnetic fields on cognitive performance in human experimental studies: A protocol for a systematic review

BACKGROUND

The World Health Organization (WHO) is currently assessing the potential health effects of exposure to radiofrequency electromagnetic fields (RF-EMFs) in the general and working population. Related to one such health effect, there is a concern that RF-EMFs may affect cognitive performance in humans. The systematic review (SR) aims to identify, summarize and synthesize the evidence base related to this question. Here, we present the protocol for the planned SR.

OBJECTIVES

The main objective is to present a protocol for a SR which will evaluate the associations between short-term exposure to RF-EMFs and cognitive performance in human experimental studies.

DATA SOURCES

We will search the following databases: PubMed, Embase, Web of Science, Scopus, and the EMF-Portal. The reference lists of included studies and retrieved review articles will be manually searched.

STUDY ELIGIBILITY AND CRITERIA

We will include randomized human experimental studies that assess the effects of RF-EMFs on cognitive performance compared to no exposure or lower exposure. We will include peer-reviewed articles of any publication date in any language that report primary data.

DATA EXTRACTION AND ANALYSIS

Data will be extracted according to a pre-defined set of forms developed and piloted by the review author team. To assess the risk of bias, we will apply the Rating Tool for Human and Animal Studies developed by NTP/OHAT, supplemented with additional questions relevant for cross-over studies. Where sufficiently similar studies are identified (e.g. the heterogeneity concerning population, exposure and outcome is low and the studies can be combined), we will conduct random-effects meta-analysis; otherwise, we will conduct a narrative synthesis.

ASSESSMENT OF CERTAINTY OF EVIDENCE

The certainty of evidence for each identified outcome will be assessed according to Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Performing the review according to this protocol will allow the identification of possible effects of RF-EMFs on cognitive performance in humans. The protocol has been registered in PROSPERO, an open-source protocol registration system, to foster transparency.

Quantifying the short-term effects of air pollution on health in the presence of exposure measurement error: a simulation study of multi-pollutant model results

BACKGROUND

Most epidemiological studies estimate associations without considering exposure measurement error. While some studies have estimated the impact of error in single-exposure models we aimed to quantify the effect of measurement error in multi-exposure models, specifically in time-series analysis of PM_2.5, NO₂, and mortality using simulations, under various plausible scenarios for exposure errors. Measurement error in multi-exposure models can lead to effect transfer where the effect estimate is overestimated for the pollutant estimated with more error to the one estimated with less error. This complicates interpretation of the independent effects of different pollutants and thus the relative importance of reducing their concentrations in air pollution policy.

METHODS

Measurement error was defined as the difference between ambient concentrations and personal exposure from outdoor sources. Simulation inputs for error magnitude and variability were informed by the literature. Error-free exposures with their consequent health outcome and error-prone exposures of various error types (classical/Berkson) were generated. Bias was quantified as the relative difference in effect estimates of the error-free and error-prone exposures.

RESULTS

Mortality effect estimates were generally underestimated with greater bias observed when low ratios of the true exposure variance over the error variance were assumed (27.4% underestimation for NO₂). Higher ratios resulted in smaller, but still substantial bias (up to 19% for both pollutants). Effect transfer was observed indicating that less precise measurements for one pollutant (NO₂) yield more bias, while the co-pollutant (PM_2.5) associations were found closer to the true. Interestingly, the sum of single-pollutant model effect estimates was found closer to the summed true associations than those from multi-pollutant models, due to cancelling out of confounding and measurement error bias.

CONCLUSIONS

Our simulation study indicated an underestimation of true independent health effects of multiple exposures due to measurement error. Using error parameter information in future epidemiological studies should provide more accurate concentration-response functions.

Electrical Conductivity and Electromagnetic Shielding Effectiveness of Bio-Composites

In this paper, the electrical conductivity and electromagnetic shielding effectiveness of two bio-composites are studied by experimental testing and numerical models. Two monolithic composites with partly bio-based content were manufactured. The first bio-composite is made of a carbon fiber fabric prepreg and a partly bio-based (rosin) epoxy resin (CF/Rosin). The second bio-composite is a combination of prepregs of carbon fiber fabric/epoxy resin and flax fiber fabric/epoxy resin (CF-Flax/Epoxy). A single line infusion process was used prior to the curing step in the autoclave. Both variants are exemplary for the possibility of introducing bio-based materials in high performance CFRP. In-plane and out-of-plane electrical conductivity tests were conducted according to Airbus standards AITM2 0064 and AITM2 0065, respectively. Electromagnetic shielding effectiveness tests were conducted based on the standard ASTM D 4935-10. Materials were prepared at the German Aerospace Center (DLR), while characterization tests were conducted at the University of Patras. In addition to the tests, numerical models of representative volume elements were developed, using the DIGIMAT software, to predict the electrical conductivity of the two bio-composites. The preliminary numerical results show a good agreement with the experimental results.

Laser stimulating ST36 with optical fiber induce blood component changes in mice: a Raman spectroscopy study

ST36 is a commonly-used acupoint in traditional Chinese medicine (TCM) for treatment of inflammations, pains and gastrointestinal disturbs. For decades, the low power laser acupuncture has been widely applied as an alternative therapy to traditional metal needle acupuncture and achieved relatively fine therapeutic effect for ST36-related symptoms with reduction of uncomfortableness and infection risks. However its disadvantages of low penetrativity and lack of manipulation skills limit its potential performance. An optical fiber laser acupuncture introduced by the previous study combines traditional needling acupuncture and the laser stimulation together, making a stronger therapeutic effect and showing a potential value in clinical application. To evaluate its acupunctural effect on blood, mice are taken as experimental model and Raman spectroscopic technique is used to analysis the changes of blood components after stimulating on ST36. The results show that both the traditional needling acupuncture and optical fiber acupuncture could lead to some spectral changes of blood in mice. This study explores the optical fiber acupuncture's effect on blood in mice using Raman spectroscopy technique for mechanism of acupuncture therapy.

Short-term effects of ambient fine particulate matter pollution on hospital visits for chronic obstructive pulmonary disease in Beijing, China

BACKGROUND

Little is known about the effect of ambient fine particulate matter (PM_2.5) on chronic obstructive pulmonary disease (COPD) in China. The objective of this study was to explore the short-term effects of PM_2.5 on outpatient and inpatient visits for COPD in Beijing, China.

METHODS

A total of 3,503,313 outpatient visits and 126,982 inpatient visits for COPD between January 1, 2010, and June 30, 2012, were identified from the Beijing Medical Claim Data for Employees. A generalized additive Poisson model was applied to estimate the percentage change with 95% confidence interval (CI) in hospital visits for COPD in relation to an interquartile range (IQR) (90.8 μg/m³) increase in PM_2.5 concentrations.

RESULTS

Short-term exposure to PM_2.5 was significantly associated with increased use of COPD-related health services. There were clear exposure-response associations of PM_2.5 with COPD outpatient and inpatient visits. An IQR increase in the concurrent day PM_2.5 concentrations was significantly associated with a 2.38% (95% CI, 2.22%-2.53%) and 6.03% (95% CI, 5.19%-6.87%) increase in daily outpatient visits and inpatient visits, respectively. Elderly people were more sensitive to the adverse effects. The estimated risk was higher during the warm season compared to the cool season.

CONCLUSIONS

Short-term exposure to PM_2.5 was associated with increased risk of hospital visits for COPD. Our findings contributed to the limited evidence concerning the effects of ambient PM_2.5 on COPD morbidity in developing countries.

Use of mobile and cordless phones and change in cognitive function: a prospective cohort analysis of Australian primary school children

BACKGROUND

Some previous studies have suggested an association between children's use of mobile phones (MPs)/cordless phones (CPs) and development of cognitive function. We evaluated possible longitudinal associations between the use of MPs and CPs in a cohort of primary school children and effects on their cognitive function.

METHODS

Data on children's socio-demographics, use of MPs and CPs, and cognitive function were collected at baseline (2010-2012) and follow-up (2012-2013). Cognitive outcomes were evaluated with the CogHealth™ test battery and Stroop Color-Word test. The change in the number of MP/CP voice calls weekly from baseline to follow-up was dichotomized: "an increase in calls" or a "decrease/no change in calls". Multiple linear regression analyses, adjusting for confounders and clustering by school, were performed to evaluate the associations between the change in cognitive outcomes and change in MP and CP exposures.

RESULTS

Of 412 children, a larger proportion of them used a CP (76% at baseline and follow-up), compared to a MP (31% at baseline and 43% at follow-up). Of 26 comparisons of changes in cognitive outcomes, four demonstrated significant associations. The increase in MP usage was associated with larger reduction in response time for response inhibition, smaller reduction in the number of total errors for spatial problem solving and larger increase in response time for a Stroop interference task. Except for the smaller reduction in detection task accuracy, the increase in CP usage had no effect on the changes in cognitive outcomes.

CONCLUSION

Our study shows that a larger proportion of children used CPs compared to MPs. We found limited evidence that change in the use of MPs or CPs in primary school children was associated with change in cognitive function.

Does exposure to environmental radiofrequency electromagnetic fields cause cognitive and behavioral effects in 10-year-old boys?

The relationship between exposure to electromagnetic fields from non-ionizing radiation and adverse human health effects remains controversial. We aimed to explore the association of environmental radiofrequency-electromagnetic fields (RF-EMFs) exposure with neurobehavioral function of children. A subsample of 123 boys belonging to the Environment and Childhood cohort from Granada (Spain), recruited at birth from 2000 through 2002, were evaluated at the age of 9-11 years. Spot electric field measurements within the 100 kHz to 6 GHz frequency range, expressed as both root mean-square (S(RMS) and maximum power density (S(MAX)) magnitudes, were performed in the immediate surrounds of childreńs dwellings. Neurocognitive and behavioral functions were assessed with a comprehensive battery of tests. Multivariate linear and logistic regression models were used, adjusting for potential confounders. All measurements were lower than reference guideline limits, with median S(RMS) and S(MAX) values of 285.94 and 2759.68 μW/m(2), respectively. Most of the cognitive and behavioral parameters did not show any effect, but children living in higher RF exposure areas (above median S(RMS) levels) had lower scores for verbal expression/comprehension and higher scores for internalizing and total problems, and obsessive-compulsive and post-traumatic stress disorders, in comparison to those living in areas with lower exposure. These associations were stronger when S(MAX) values were considered. Although some of our results may suggest that low-level environmental RF-EMF exposure has a negative impact on cognitive and/or behavior development in children; given limitations in the study design and that the majority of neurobehavioral functioning tasks were not affected, definitive conclusions cannot be drawn.

Outdoor and indoor sources of residential radiofrequency electromagnetic fields, personal cell phone and cordless phone use, and cognitive function in 5-6 years old children

BACKGROUND

Little is known about the exposure of young children to radiofrequency electromagnetic fields (RF-EMF) and potentially associated health effects. We assessed the relationship between residential RF-EMF exposure from mobile phone base stations, residential presence of indoor sources, personal cell phone and cordless phone use, and children's cognitive function at 5-6 years of age.

METHODS

Cross-sectional study on children aged 5-6 years from the Amsterdam Born Children and their Development (ABCD) study, the Netherlands (n=2354). Residential RF-EMF exposure from mobile phone base stations was estimated with a 3D geospatial radio wave propagation model. Residential presence of indoor sources (cordless phone base stations and Wi-Fi) and children's cell phone and cordless phone use was reported by the mother. Speed of information processing, inhibitory control, cognitive flexibility, and visuomotor coordination was assessed using the Amsterdam Neuropsychological Tasks.

RESULTS

Residential presence of RF-EMF indoor sources was associated with an improved speed of information processing. Higher residential RF-EMF exposure from mobile phone base stations and presence of indoor sources was associated with an improved inhibitory control and cognitive flexibility whereas we observed a reduced inhibitory control and cognitive flexibility with higher personal cordless phone use. Higher residential RF-EMF exposure from mobile phone base stations was associated with a reduced visuomotor coordination whereas we observed an improved visuomotor coordination with residential presence of RF-EMF indoor sources and higher personal cell phone use.

CONCLUSIONS

We found inconsistent associations between different sources of RF-EMF exposure and cognitive function in children aged 5-6 years.

Burden of disease resulting from lead exposure at toxic waste sites in Argentina, Mexico and Uruguay

BACKGROUND

Though lead contaminated waste sites have been widely researched in many high-income countries, their prevalence and associated health outcomes have not been well documented in low- and middle-income countries.

METHODS

Using the well-established health metric disability-adjusted life year (DALY) and an exposure assessment method developed by Chatham-Stephens et al., we estimated the burden of disease resulting from exposure to lead at toxic waste sites in three Latin American countries in 2012: Argentina, Mexico and Uruguay. Toxic waste sites identified through Pure Earth's Toxic Sites Identification Program (TSIP) were screened for lead in both biological and environmental sample media. Estimates of cardiovascular disease incidence and other outcomes resulting from exposure to lead were utilized to estimate DALYs for each population at risk.

RESULTS

Approximately 316,703 persons in three countries were at risk of exposure to pollutants at 129 unique sites identified through the TSIP database. Exposure to lead was estimated to result in between 51,432 and 115,042 DALYs, depending on the weighting factor used. The estimated burden of disease caused by exposure to lead in this analysis is comparable to that estimated for Parkinson's disease and bladder cancer in these countries.

CONCLUSIONS

Lead continues to pose a significant public health risk in Argentina, Mexico, and Uruguay. The burden of disease in these three countries is comparable with other widely recognized public health challenges. Knowledge of the relatively high number of DALYs associated with lead exposure may be used to generate support and funding for the remediation of toxic waste sites in these countries and others.

Acute effects of 3G mobile phone radiations on frontal haemodynamics during a cognitive task in teenagers and possible protective value of Om chanting

Mobile phone induced electromagnetic field (MPEMF) as well as chanting of Vedic mantra 'OM' has been shown to affect cognition and brain haemodynamics, but findings are still inconclusive. Twenty right-handed healthy teenagers (eight males and 12 females) in the age range of 18.25 ± 0.44 years were randomly divided into four groups: (1) MPONOM (mobile phone 'ON' followed by 'OM' chanting); (2) MPOFOM (mobile phone 'OFF' followed by 'OM' chanting); (3) MPONSS (mobile phone 'ON' followed by 'SS' chanting); and (4) MPOFSS (mobile phone 'OFF' followed by 'SS' chanting). Brain haemodynamics during Stroop task were recorded using a 64-channel fNIRS device at three points of time: (1) baseline, (2) after 30 min of MPON/OF exposure, and (3) after 5 min of OM/SS chanting. RM-ANOVA was applied to perform within- and between-group comparisons, respectively. Between-group analysis revealed that total scores on incongruent Stroop task were significantly better after OM as compared to SS chanting (MPOFOM vs MPOFSS), pre-frontal activation was significantly lesser after OM as compared to SS chanting in channel 13. There was no significant difference between MPON and MPOF conditions for Stroop performance, as well as brain haemodynamics. These findings need confirmation through a larger trial in future.

Cohort Profile Update: The China Jintan Child Cohort Study

The China Jintan Child Cohort study began in 2004 with 1656 pre-school participants and a research focus on studying the impact of environmental exposures, such as lead, on children's neurobehavioural outcomes. This population cohort now includes around 1000 of the original participants, who have been assessed three times over a period of 10 years. Since the original IJE cohort profile publication in 2010, participants have experienced a critical developmental transition from pre-school to school age and then adolescence. The study has also witnessed an increase in breadth and depth of data collection from the original aim of risk assessment. This cohort has added new directions to investigate the mechanisms and protective factors for the relationship between early health factors and child physical and mental health outcomes, with an emphasis on neurobehavioural consequences. The study now encompasses 11 domains, composed of repeated measures of the original variables and new domains of biomarkers, sleep, psychophysiology, neurocognition, personality, peer relationship, mindfulness and family dynamics. Depth of evaluation has increased from parent/teacher report to self/peer report and intergenerational family report. Consequently, the cohort has additional directions to include: (i) classmates of the original cohort participants for peer relationship assessment; and (ii) parental and grandparental measures to assess personality and dynamics within families. We welcome interest in our study and ask investigators to contact the corresponding author for additional information on data acquisition.

Do signals of a hand-held TETRA transmitter affect cognitive performance, well-being, mood or somatic complaints in healthy young men? Results of a randomized double-blind cross-over provocation study

BACKGROUND

TETRA (terrestrial trunked radio) is a digital radio communication standard, which has been implemented in several European countries and is used by public executives, transportation services, and by private companies. Studies on possible impacts on the users' health considering different exposure conditions are missing.

OBJECTIVES

To investigate possible acute effects of electromagnetic fields (EMF) of two different levels of TETRA hand-held transmitter signals on cognitive function and well-being in healthy young males.

METHODS

In the present double-blind cross-over study possible effects of short-term (2.5h) EMF exposure of handset-like signals of TETRA (385 MHz) were studied in 30 healthy male participants (mean±SD: 25.4±2.6 years). Individuals were tested on nine study days, on which they were exposed to three different exposure conditions (Sham, TETRA 1.5 W/kg and TETRA 6.0 W/kg) in a randomly assigned and balanced order. Participants were tested in the afternoon at a fixed timeframe.

RESULTS

Attention remained unchanged in two out of three tasks. In the working memory significant changes were observed in two out of four subtasks. Significant results were found in 5 out of 35 tested parameters, four of them led to an improvement in performance. Mood, well-being and subjective somatic complaints were not affected by TETRA exposure.

CONCLUSIONS

The results of the present study do not indicate a negative impact of a short-term EMF-effect of TETRA on cognitive function and well-being in healthy young men.

EEG Changes Due to Experimentally Induced 3G Mobile Phone Radiation

The aim of this study was to investigate whether a 15-minute placement of a 3G dialing mobile phone causes direct changes in EEG activity compared to the placement of a sham phone. Furthermore, it was investigated whether placement of the mobile phone on the ear or the heart would result in different outcomes. Thirty-one healthy females participated. All subjects were measured twice: on one of the two days the mobile phone was attached to the ear, the other day to the chest. In this single-blind, cross-over design, assessments in the sham phone condition were conducted directly preceding and following the mobile phone exposure. During each assessment, EEG activity and radiofrequency radiation were recorded jointly. Delta, theta, alpha, slowbeta, fastbeta, and gamma activity was computed. The association between radiation exposure and the EEG was tested using multilevel random regression analyses with radiation as predictor of main interest. Significant radiation effects were found for the alpha, slowbeta, fastbeta, and gamma bands. When analyzed separately, ear location of the phone was associated with significant results, while chest placement was not. The results support the notion that EEG alterations are associated with mobile phone usage and that the effect is dependent on site of placement. Further studies are required to demonstrate the physiological relevance of these findings.

Does the Brain Detect 3G Mobile Phone Radiation Peaks? An Explorative In-Depth Analysis of an Experimental Study

This study aimed to investigate whether third generation mobile phone radiation peaks result in event related potentials. Thirty-one healthy females participated. In this single-blind, cross-over design, a 15 minute mobile phone exposure was compared to two 15 minute sham phone conditions, one preceding and one following the exposure condition. Each participant was measured on two separate days, where mobile phone placement was varied between the ear and heart. EEG activity and radiofrequency radiation were recorded jointly. Epochs of 1200 ms, starting 200 ms before and lasting until 1000 ms after the onset of a radiation peak, were extracted from the exposure condition. Control epochs were randomly selected from the two sham phone conditions. The main a-priori hypothesis to be tested concerned an increase of the area in the 240-500 ms post-stimulus interval, in the exposure session with ear-placement. Using multilevel regression analyses the placement*exposure interaction effect was significant for the frontal and central cortical regions, indicating that only in the mobile phone exposure with ear-placement an enlarged cortical reactivity was found. Post-hoc analyses based on visual inspection of the ERPs showed a second significantly increased area between 500-1000 ms post-stimulus for almost every EEG location measured. It was concluded that, when a dialing mobile phone is placed on the ear, its radiation, although unconsciously, is electrically detected by the brain. The question of whether or not this cortical reactivity results in a negative health outcome has to be answered in future longitudinal experiments.

Using medaka embryos as a model system to study biological effects of the electromagnetic fields on development and behavior

The electromagnetic fields (EMFs) of anthropogenic origin are ubiquitous in our environments. The health hazard of extremely low frequency and radiofrequency EMFs has been investigated for decades, but evidence remains inconclusive, and animal studies are urgently needed to resolve the controversies regarding developmental toxicity of EMFs. Furthermore, as undersea cables and technological devices are increasingly used, the lack of information regarding the health risk of EMFs to aquatic organisms needs to be addressed. Medaka embryos (Oryzias latipes) have been a useful tool to study developmental toxicity in vivo due to their optical transparency. Here we explored the feasibility of using medaka embryos as a model system to study biological effects of EMFs on development. We also used a white preference test to investigate behavioral consequences of the EMF developmental toxicity. Newly fertilized embryos were randomly assigned to four groups that were exposed to an EMF with 3.2kHz at the intensity of 0.12, 15, 25, or 60µT. The group exposed to the background 0.12µT served as the control. The embryos were exposed continually until hatch. They were observed daily, and the images were recorded for analysis of several developmental endpoints. Four days after hatching, the hatchlings were tested with the white preference test for their anxiety-like behavior. The results showed that embryos exposed to all three levels of the EMF developed significantly faster. The endpoints affected included the number of somites, eye width and length, eye pigmentation density, midbrain width, head growth, and the day to hatch. In addition, the group exposed to the EMF at 60µT exhibited significantly higher levels of anxiety-like behavior than the other groups did. In conclusion, the EMF tested in this study accelerated embryonic development and heightened anxiety-like behavior. Our results also demonstrate that the medaka embryo is a sensitive and cost-efficient in vivo model system to study developmental toxicity of EMFs.

Searching for the perfect wave: the effect of radiofrequency electromagnetic fields on cells

There is a growing concern in the population about the effects that environmental exposure to any source of “uncontrolled” radiation may have on public health. Anxiety arises from the controversial knowledge about the effect of electromagnetic field (EMF) exposure to cells and organisms but most of all concerning the possible causal relation to human diseases. Here we reviewed those in vitro and in vivo and epidemiological works that gave a new insight about the effect of radio frequency (RF) exposure, relating to intracellular molecular pathways that lead to biological and functional outcomes. It appears that a thorough application of standardized protocols is the key to reliable data acquisition and interpretation that could contribute a clearer picture for scientists and lay public. Moreover, specific tuning of experimental and clinical RF exposure might lead to beneficial health effects.

Effect of microwave radiation on human EEG at two different levels of exposure

This study is aimed at evaluating the effect of microwave radiation on human brain bioelectric activity at different levels of exposure. For this purpose, 450 MHz microwave exposure modulated at 40 Hz frequency was applied to a group of 15 healthy volunteers at two different specific absorption rate (SAR) levels: a higher level of 0.303 W/kg (field strength 24.5 V/m) and a lower level of 0.003 W/kg (field strength 2.45 V/m). Ten exposure cycles (1 min off and 1 min on) at fixed SAR values were applied. A resting eyes-closed electroencephalogram (EEG) was continuously recorded. Results showed a statistically significant increase in the EEG power in the EEG beta2 (157%), beta1 (61%) and alpha (68%) frequency bands at the higher SAR level, and in the beta2 (39%) frequency band at the lower SAR level. Statistically significant changes were detected for six individual subjects in the EEG alpha band and four subjects in the beta1 and beta2 bands at the higher SAR level; three subjects were affected in the alpha, beta1 and beta2 bands at the lower SAR level. The study showed that decreasing the SAR 100 times reduced the related changes in the EEG three to six times and the number of affected subjects, but did not exclude the effect.

Electromagnetic fields at 2.45 GHz trigger changes in heat shock proteins 90 and 70 without altering apoptotic activity in rat thyroid gland

Non-ionizing radiation at 2.45 GHz may modify the expression of genes that codify heat shock proteins (HSP) in the thyroid gland. Using the enzyme-linked immunosorbent assay (ELISA) technique, we studied levels of HSP-90 and HSP-70. We also used hematoxilin eosin to look for evidence of lesions in the gland and applied the DAPI technique of fluorescence to search for evidence of chromatin condensation and nuclear fragmentation in the thyroid cells of adult female Sprague-Dawley rats. Fifty-four rats were individually exposed for 30 min to 2.45 GHz radiation in a Gigahertz transverse electromagnetic (GTEM) cell at different levels of non-thermal specific absorption rate (SAR), which was calculated using the finite difference time domain (FDTD) technique. Ninety minutes after radiation, HSP-90 and HSP-70 had decreased significantly (P<0.01) after applying a SAR of 0.046±1.10 W/Kg or 0.104±5.10⁻³ W/Kg. Twenty-four hours after radiation, HSP-90 had partially recovered and HSP-70 had recovered completely. There were few indications of lesions in the glandular structure and signs of apoptosis were negative in all radiated animals. The results suggest that acute sub-thermal radiation at 2.45 GHz may alter levels of cellular stress in rat thyroid gland without initially altering their anti-apoptotic capacity.