Although the beam-forming characteristic of the 5G mMIMO base station has strong beam directivity, and the electromagnetic radiation intensity of 5G base station also has a strong relationship with the user's download rate, however, in the most extreme application scenario of eMBB high-speed downlink lasting 6min without interruption, through frequency selection monitoring, the electromagnetic radiation level of 5G shared base stations with the maximum power of 320W and 200M working bandwidth in China's commercial network is far lower than China's national limit standard and international standard, which also shows that the high power, high frequency and high speed 5G network does not necessarily mean the safety problem of electromagnetic radiation. In fact, the electromagnetic environment quality of the sensitive area around the base station can still meet the national standard.
In addition, considering that China's national standard limit requirements are 15-25 times stricter than international standards, most countries have adopted more relaxed limit requirements for public exposure to 5G electromagnetic radiation, therefore, combined with the in-situ monitoring results obtained under the extreme eMBB application scenarios, which are far lower than the requirements of the national limit standard GB8702-2014, as long as the operators can timely do the pre-assessment of radiation risk before the base station construction and routine monitoring during operation, the electromagnetic radiation risk in sensitive areas covered by 5G
Human exposure to electromagnetic fields emitted by mobile communications sources is dominated by the mobile phone radiation. Not only the dose of radiation is important, but also dose- or fluence-rate. In this regard, present research emphasizes the features of the dynamics of mobile terminal emission levels by means of statistics, nonlinear data analysis with recurrence quantification and time-frequency analyses. Time series of radiated electric field strengths were recorded and processed for a set of five mobile applications usage per communication standard. Both 4G-LTE emission channel of 20 MHz bandwidth and 5G-NR FR1 emission channel with a bandwidth of 40 MHz were studied. Differences between 4G and 5G emissions variabilities are presented, and application-specific features of the time imprint are highlighted.
Methods: The first one was centered in the lower 5G band, around f = 3.5 GHz, whereas the second one was tuned to the upper 5G band, at 26.5 GHz. Both antennas were positioned on the trunk of four simulated human models. The exposure assessment was performed by electromagnetic numerical simulations. Exposure levels were assessed by quantifying the specific absorption rate averaged on 10 g of tissue (SAR10g) and the absorbed power density (Sab), depending on the frequency of the wearable antenna.
Results: the higher exposure values that resulted were always mainly concentrated in a superficial area just below the antenna itself. In addition, these resulting distributions were narrowed around their peak values and tended to flatten toward lower values in farther anatomical body regions. All the exposure levels complied with ICNIRP guidelines when considering realistic input power.
Conclusions: This work highlights the importance of performing an exposure assessment when the antenna is placed on the human wearer, considering the growth of wearable technology and its wide variety of application, particularly regarding future 5G networks.
Open access paper:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9823937/
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A high-resolution pediatric female whole-body numerical model with comparison to a male model
Ntolkeras G, Jeong H, Zollei L, Dmytriw AA, Purvaziri A, Lev MH, Grant PE, Bonmassar G. A high-resolution pediatric female whole-body numerical model with comparison to a male model. Phys Med Biol. 2022 Dec 6. doi: 10.1088/1361-6560/aca950.
Abstract
Objective: Numerical models are central in designing and testing novel medical devices and in studying how different anatomical changes may affect physiology. Despite the numerous adult models available, there are only a few whole-body pediatric numerical models with significant limitations. In addition, there is a limited representation of both male and female biological sexes in the available pediatric models despite the fact that sex significantly affects body development, especially in a highly dynamic population. As a result, we developed Athena, a realistic female whole-body pediatric numerical model with high-resolution and anatomical detail.
Approach: We segmented different body tissues through Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) images of a healthy 3.5-year-old female child using 3D Slicer. We validated the high anatomical accuracy segmentation through two experienced sub-specialty-certified neuro-radiologists and the inter and intra-operator variability of the segmentation results comparing sex differences in organ metrics with physiologic values. Finally, we compared Athena with Martin, a similar male model, showing differences in anatomy, organ metrics, and MRI dosimetric exposure.
Main results: We segmented 267 tissue compartments, which included 50 brain tissue labels. The tissue metrics of Athena displayed no deviation from the literature value of healthy children. We show the variability of brain metrics in the male and female models. Finally, we offer an example of computing Specific Absorption Rate (SAR) and Joule heating in a toddler/preschooler at 7T MRI.
Significance: This study introduces a female realistic high-resolution numerical model using MRI and CT scans of a 3.5-year-old female child, the use of which includes but is not limited to radiofrequency safety studies for medical devices (e.g., an implantable medical device safety in MRI), neurostimulation studies, and radiation dosimetry studies. This model will be open source and available on the Athinoula A. Martinos Center for Biomedical Imaging website.
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Human
Health Risk Assessment of 4-12 GHz Radar Waves using CST STUDIO SUITE
Software
Fereidouni F, Mohammadi ST, Faramarzi Shahraki V, Jahantigh F. Human
Health Risk Assessment of 4-12 GHz Radar Waves using CST STUDIO SUITE
Software. J Biomed Phys Eng. 2022 Jun 1;12(3):285-296. doi:
10.31661/jbpe.v0i0.1272.
Background:
The application of radar systems in telecommunications and
aerospace science is important. However, engineering department's staff
various tissues are always under chronic radiation generated by the
radar fields which may affect health.
Objective:
This study aims to evaluate the risk of radar wave exposure and to explore the effects and limitations.
Material and methods:
In this simulation study, an adult body model versus 1 watt source
with a distance of 50 centimeters exposure has been simulated using the
CST STUDIO SUITE. Furthermore, various physical and electrical
properties of each tissue and organ for different frequencies and
exposure times have been studied. The exposure dose limitations have
been considered using the International Commission on Non-Ionizing
Radiation Protection (ICNIRP) safety and health guide report.
Results:
Total body absorbed doses for 4 GHz, 8 GHz, and 12 GHz frequency,
and 6 min, 4 h, and 30 days exposure time, have been calculated as
1.136×10-5, 1.598×10-5, 1.58×10-3, 1.521×10-5, 3.122×10-5, 4.52×10-3, 4.1×10-5, 10-4, and 10-2, respectively.
Conclusion:
It has shown that the internal organs of the body and head will be
under more risk by reducing radar frequencies from 12 GHz to 4 GHz. On
the other hand, the higher frequency can cause a higher risk to the
human skin. In addition, the maximum Specific Absorption Rate (SAR) for
each case has been calculated. The results show that for this normalized
source, the safety criteria have been respected, but for a higher
source, the calculations must be repeated.
Conclusion
In this paper, an accurate and comprehensive model of the adult body tissues using the CST Studio Suite software is developed. The effect of EM radiation on the human body was studied for the frequency range of 4 to 12 GHz over a specified period of 6 min, 4 h and 30 days. It can be concluded that the effects are inversely related to the frequency increase. In other words, the longer the wavelength of the electromagnetic field can cause further penetration in the human body and severe effects in the vital organs of the body. The longer exposure time can cause a severe effect. In addition, by examining the pattern of wave propagation in the body, it was seen that in the oral cavities filled with the air, there is a loss of wavelength and the waves tend to fall into the inner tissues which have absorption coefficient. Excluding the body skin, the power loss in the other organs monolithically decreased with frequency increase, and the power loss increases by the exposure time so that for 30 days exposure, it has nearly 2 orders of magnitude more absorption at different organs. The power loss diagram, SAR diagram, and the body organs risk caused by radar waves show the rate of vulnerability of the abdominal cavity and the head. The risk of the body skin disease in the lower frequencies has increased. Furthermore, the skin surface is more vulnerable and the chance of skin complications increases at higher frequencies up to 12 GHz. It should also be emphasized that for the body of those people whose workplace interact with radar waves exceeding the limit point of -10.96 dB, the critical risk of the body’s vital organs increases. As a result, the standard limits should be considered for safety and health of the staff in the radar sites.
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Grounding (earthing) as related to electromagnetic hygiene: An integrative reviewJamieson IA. Grounding (earthing) as related to electromagnetic hygiene: An integrative review. Biomedical Journal, 2022, doi:10.1016/j.bj.2022.11.005.
Abstract
There are a growing number of studies investigating how grounding (earthing) the body may benefit biological performance and aid the treatment of non-communicable diseases. Research also indicates how biological grounding initiatives can sometimes be compromised, or inappropriate, and the need to take additional factors into account as potential contributory factors, or confounders, to expected results. It is proposed that expanding electromagnetic hygiene measures beyond biological grounding alone may help reduce spread of communicable diseases, incidence of respiratory conditions, neurodegenerative disease and all-cause mortality. Identifying potential synergies that exist could enable multilevel interventions to further increase the efficacy of measures. It is hoped that this review will help act as a catalyst to inspire and inform multi-disciplinary research within these topic areas, best practices and policies to help drive medical innovation, reduce health burdens, improve bioelectromagnetic-based therapies, and influence the general design of the built environment and next-generation technologies.
Open access paper:
https://www.sciencedirect.com/science/article/pii/S2319417022001573
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Assessment of the Electromagnetic Radiation Exposure at
Electric Vehicle Charging Facilities
Bae H, Park S. Assessment of the Electromagnetic Radiation Exposure at
EV Charging Facilities. Sensors (Basel). 2022 Dec 23;23(1):162. doi:
10.3390/s23010162
Abstract
As the number of electric vehicles (EV) increases, the number of EV
chargers also increases. Charging infrastructure will be built into our
close environment. Because of this, the assessment of the
electromagnetic field exposure generated from the charger is an
important issue. This paper valuates the electromagnetic field exposure
of six EV chargers. To assess the level of exposure of EV chargers, the
electromagnetic fields from six chargers were measured and analyzed. In
addition, measured electromagnetic field exposure levels were evaluated
against ICNIRP guidelines. Higher electromagnetic fields were measured
with standard chargers than with fast chargers. For the fast charger in
the charging state, the magnetic field increased with the charging
current. Electromagnetic field exposures for all six chargers did not
exceed standard limits. The results of the assessment of the
electromagnetic field exposure of the six EV chargers will contribute to
the establishment of standards for the evaluation of the
electromagnetic field exposure of the EV chargers in the future.
Conclusion
In
this study, electromagnetic field exposure assessment results of six EV
chargers were presented. These results show the location where the
electromagnetic field is the highest measured among electric vehicle
chargers in the charging situation. They also show the correlation
between changes in the electromagnetic field and changes in the SoC. The
measured value of the electromagnetic field was analyzed by comparing
it with domestic and global electromagnetic field intensity standard.
The domestic electromagnetic field intensity standards were in agreement
with the ICNIRP guidelines revised in 1998 and were analyzed based on
them.
Six EV chargers were selected for measurement. The level of
exposure to electromagnetic fields was confirmed by precisely measuring
six types of chargers in RMS mode under charging conditions. In
addition, the electromagnetic field changed as the SoC changed. Because
of RMS precision measurement, a relatively higher electromagnetic field
was emitted from a standard charger than from a fast charger. The
maximum electric field was measured at the standard stand-type B handle,
and it was 430 V/m, corresponding to an EI of 10%. The maximum magnetic
field was measured on a standard wall-mounted body and was 46 A/m,
corresponding to an EI of 69%. None of the six chargers exceeded the
electromagnetic field protection standard.
Changes in electric and
magnetic fields were confirmed by the changes in the SoC [state of charge] of six
chargers. In the case of fast charging facilities, as the charging power
and current gradually decreased, it was confirmed that the level of
magnetic field strength decreased accordingly. In the case of standard
charging facilities, the correlation between charging power, voltage,
current, and electric and magnetic field strength could not be
confirmed. In addition, changes in the electromagnetic field were
observed with changes in the SoC. Generally, the maximum value of the
electromagnetic field was measured in the measurement results by the
change in the SoC. This result indicates the need to verify
electromagnetic field measurements as the change in the SoC.
Because
of these results, the measurement procedure when preparing a method to
evaluate the amount of exposure to electromagnetic fields in EV charging
facilities is worth reviewing in the future. When charging an EV, the
measurement location of maximum electromagnetic field exposure is
necessary. Therefore, first, an understanding of the overall
electromagnetic field strength of the charging facility is necessary.
The maximum value after measurements according to the change from 0% to
100% of the SoC at the location of maximum exposure is worth recording.
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Electromagnetic Radiation Safety on Far-Field Wireless Power Transfer in IoT
Ma F, Liu X, Ansari N. Electromagnetic Radiation Safety on Far-field Wireless Power Transfer in IoT. GLOBECOM 2022 - 2022 IEEE Global Communications Conference, Rio de Janeiro, Brazil, 2022, pp. 4995-5000, doi: 10.1109/GLOBECOM48099.2022.10001490.
Abstract
Nowadays, Far-field Wireless Power Transfer (FWPT) has attracted many
research efforts to conveniently power the Internet of Things (IoT)
devices. Electromagnetic Radiation (EMR) safety in FWPT has brought much
attention from the public. Existing works on FWPT mainly focus on
improving the remote charging efficiency but overlooking the effects of
EMR. A few works consider EMR safety but do not present accurate EMR
quantization analysis because there lacks an accurate EMR computing
model in IoT wireless charging scenario. In this paper, in order to
evaluate and avoid the EMR's harmful impact, we first propose an
accurate theoretical calculation equation for EMR and the concept of
Charging Restricted Area (CRA). In the wireless charging area on a
2-dimensional plane, according to the EMR computing model, we further
maximize the overall charging power by adjusting the power of chargers
and ensure that the EMR in this area is lower than the EMR safety
threshold. The wireless charging EMR safety problem is formulated as a
linear programming problem with infinite constraints. To re-express the
wireless charging EMR safety problem as a typical linear programming
problem with finite constraints, the Sampling Safety Charging (SSC)
algorithm is proposed. We have conducted extensive experiments to
validate our proposed algorithm; the simulation results show that the
performance achieved by our algorithm outperforms that achieved by the
distributed RObustlySafE (ROSE) algorithm.
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Estimating exposure to extremely low frequency magnetic fields near
high-voltage power lines and assessment of possible increased cancer
risk among Slovenian children and adolescents
Zagar T, Valic B, Kotnik T, Korat S, Tomsic S, Zadnik V, Gajsek P.
Estimating exposure to extremely low frequency magnetic fields near
high-voltage power lines and assessment of possible increased cancer
risk among Slovenian children and adolescents. Radiol Oncol. 2023 Jan 8.
doi: 10.2478/raon-2023-0002.
Abstract
Background: Some previous research showed that average daily exposure to extremely low frequency (ELF) magnetic fields (MF) of more than 0.3 or 0.4 μT could potentially increase risk of childhood leukaemia.
Materials and methods: To allow calculations of ELF MF around high voltage (HV) power lines (PL) for the whole Slovenia, a new three-dimensional method including precision terrain elevation data was developed to calculate the long-term average ELF MF. Data on population of Slovenian children and adolescents and on cancer patients with leukaemia's aged 0-19 years, brain tumours at age 0-29, and cancer in general at age 0-14 for a 12-year period 2005-2016 was obtained from the Slovenian Cancer Registry.
Results: According to the large-scale calculation for the whole country, only 0.5% of children and adolescents under the age of 19 in Slovenia lived in an area near HV PL with ELF MF density greater than 0.1 μT. The risk of cancer for children and adolescents living in areas with higher ELF MF was not significantly different from the risk of their peers.
Conclusions: The new method enables relatively fast calculation of the value of low-frequency magnetic fields for arbitrary loads of the power distribution network, as the value of each source for arbitrary load is calculated by scaling the value for nominal load, which also enables significantly faster adjustment of calculated estimates in the power distribution network.
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Evaluation of cognitive functions and EEG records in rats exposed to 2.45 GHz electromagnetic field
Yucel H, Dundar NO, Doguc DK, Uguz C, Celik O, Aksoy FT, Nazıroglu M, Comlekci S, Dundar B. Evaluation of cognitive functions and EEG records in rats exposed to 2.45 GHz electromagnetic field.
Int J Radiat Res 2022, 20(4): 753-760.
Abstract
Background: Electromagnetic fields may primarily affect cognitive functions. It has not been elucidated how electromagnetic radiation affects the brain, particularly in the young age group. We aimed to examine the cognitive function, expression of N-methyl-D-aspartate receptors (NMDA), and EEG alterations in weaned rats exposed to a 2.45 GHz electromagnetic field.
Materials and Methods: Twenty-one weaned (21 days old) male Wistar Albino rats were divided into two groups as experimental group (n=12) and control group (n=9). Animals in the experimental group were exposed to a 2.45 GHz electromagnetic field for one hour a day for more than 28 days. At the end of this period, rats were subjected to training and learning test using Morris Water Maze. After obtaining EEG records, hippocampi were removed. 2A and 2B subunits of NMDA receptors were studied in hippocampal homogenates using the Western Blot method.
Results: There were no statistically significant differences between the two groups in measures of latency to target quadrant, time spent in the target quadrant, and average swim speed as compared in Morris water maze. However, the time to arrive at the visible platform was significantly longer in experimental animals. There were no statistically significant differences in expression of 2A and 2B subunits of NMDA receptors between the two groups. Evaluation of EEG records revealed that spike frequency was significantly higher and time to first spike was significantly shorter in the experimental group.
Conclusion: These results indicated that a 2.45 GHz electromagnetic field might negatively affect EEG, motivation, and attention, particularly in the young age group.
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Effects of ELF-PEMF
exposure on spontaneous alternation, anxiety, motor co-ordination and
locomotor activity of adult wistar rats and viability of C6 (Glial)
cells in culture
Tekam CKS, Majumdar S, Kumari P, Prajapati SK, Sahi AK, Shinde S, Singh
R, Samaiya PK, Patnaik R, Krishnamurthy S, Mahto SK. Effects of ELF-PEMF
exposure on spontaneous alternation, anxiety, motor co-ordination and
locomotor activity of adult wistar rats and viability of C6 (Glial)
cells in culture. Toxicology. 2022 Dec 24;485:153409. doi:
10.1016/j.tox.2022.153409.
Abstract
The effects of ELF-PEMF exposure on spontaneous alternation, anxiety,
motor coordination, and locomotor activity have been discussed in
various pre-clinical and clinical settings. Several epidemiological and
experimental studies have demonstrated the potential effects of ELF-PEMF
when exposed > ∼1 h/day; however, very few studies have focused on
understanding the influence of ELF-PEMF exposure of 1-3 mT with an
exposure duration of < 1 h/day on spontaneous alternation, anxiety,
motor coordination, and locomotor activity. Hence, we attempted to study
the effects of ELF-PEMF exposure of 1-3 mT, 50 Hz with an exposure
duration of 20 min each with a 4 h gap (2 times) on the cellular
proliferation and morphologies of C6 (Glial) cells and spontaneous
alternation, anxiety, motor coordination and locomotor activity of
Wistar rats under in vitro and in vivo conditions, respectively. The
results showed that ELF-PEMF exposure did not induce any significant
levels of cellular fragmentation and changes in the morphology of glial
cells. Also, the outcomes revealed no noticeable effects on spontaneous
alternation, anxiety, motor coordination, and locomotor activity in
PEMF-exposed groups compared with the control. No undesirable side
effects were observed at the highest dose (B=3 mT). We also performed
histological analysis of the selected brain sections (hippocampus and
cortex) following ELF-PEMF exposure. Incidentally, no significant
changes were observed in cortical cell counts, tissue structure, and
morphology.
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Influence of
electromagnetic fields on the circadian rhythm: Implications for human
health and disease
Martel J, Chang SH, Chevalier G, Ojcius DM, Young JD. Influence of
electromagnetic fields on the circadian rhythm: Implications for human
health and disease. Biomed J. 2023 Jan 18:S2319-4170(23)00003-3. doi:
10.1016/j.bj.2023.01.003.
Abstract
Living organisms have evolved within the natural electromagnetic fields
of the earth which comprise atmospheric electricity, Schumann resonances
and the geomagnetic field. Research suggests that the circadian rhythm,
which controls several physiological functions in the human body, can
be influenced by light but also by the earth's electromagnetic fields.
Cyclic solar disturbances, including sunspots and seasonal weakening of
the geomagnetic field, can affect human health, possibly by disrupting
the circadian rhythm and downstream physiological functions. Severe
disruption of the circadian rhythm increases inflammation which can
induce fatigue, fever and flu-like symptoms in a fraction of the
population and worsen existing symptoms in old and diseased individuals,
leading to periodic spikes of infectious and chronic diseases. Possible
mechanisms underlying sensing of the earth's electromagnetic fields
involve entrainment, light-dependent radical pair formation in retina
cryptochromes, and paramagnetic magnetite nanoparticles. Factors such as
electromagnetic pollution from wireless devices and antennas, shielding
by non-conductive materials used in shoes and buildings, and local
geomagnetic anomalies may also affect sensing of the earth's
electromagnetic fields by the human body and contribute to circadian
rhythm disruption and disease development.
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The Effects
of Prenatal and Postnatal Exposure to 50-Hz and 3 mT Electromagnetic
Field on Rat Testicular Development
Ersoy N, Acikgoz B, Aksu I, Kiray A, Bagriyanik HA, Kiray M. The Effects
of Prenatal and Postnatal Exposure to 50-Hz and 3 mT Electromagnetic
Field on Rat Testicular Development. Medicina (Kaunas). 2022 Dec
29;59(1):71. doi: 10.3390/medicina59010071.
Abstract
Background and objectives: It has been shown that electromagnetic
fields (EMFs) have negative effects on the reproductive system. The
biological effects of EMF on the male reproductive system are
controversial and vary depending on the frequency and exposure time.
Although a limited number of studies have focused on the structural and
functional effects of EMF, the effects of prenatal and postnatal EMF
exposure on testes are not clear. We aimed to investigate the effects of
50-Hz, 3-mT EMF exposure (5 days/wk, 4 h/day) during pre- and postnatal
periods on testis development. Materials and Methods: Pups from
three groups of Sprague-Dawley pregnant rats were used: Sham, EMF-28
(EMF-exposure applied during pregnancy and until postnatal day 28),
EMF-42 (EMF-exposure applied during pregnancy and until postnatal day
42). The testis tissues and blood samples of male offspring were
collected on the postnatal day 42. Results: Morphometric analyses
showed a decrease in seminiferous tubule diameter as a result of
testicular degeneration in the EMF-42 group. Follicle-stimulating
hormone (FSH) and luteinizing hormone (LH) levels were decreased in the
EMF-42 group. Lipid peroxidation levels were increased in both EMF
groups, while antioxidant levels were decreased only in the EMF-28
group. We found decreased levels of vascular endothelial growth factor
(VEGF) and insulin-like growth factor-1 (IGF1) in the EMF-42 group, and
decreased levels of the SRC homology 3 (SH3) and multiple ankyrin repeat
domain (SHANK3) in the EMF-28 group in the testis tissue. Conclusions:
EMF exposure during pre- and postnatal periods may cause deterioration
in the structure and function of testis and decrease in growing factors
that would affect testicular functions in male rat pups. In addition to
the oxidative stress observed in testis, decreased SHANK3, VEGF, and
IGF1 protein levels suggests that these proteins may be mediators in
testis affected by EMF exposure. This study shows that EMF exposure
during embryonic development and adolescence can cause apoptosis and
structural changes in the testis.
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Effects of 150 kHz intermediate frequency electromagnetic radiation on fertility indicators in male rats
Sundaram V, Mohammed S, Zyuzikov N. Effects of 150 kHz intermediate frequency electromagnetic radiation on fertility indicators in male rats. Heliyon. 8(12). 2022. doi: 10.1016/j.heliyon.2022.e12228.
Abstract
Background The present study aimed to evaluate the effects of whole-body exposure to 150 kHz Intermediate-frequency electromagnetic radiation (IF EMR) on fertility indicators of male rats since human exposure to this frequency has increased in recent years. Fourteen adult male Sprague-Dawley rats were used in this study. The rats were randomly divided into a control and an EMR group (n = 7/group). The EMR group was continuously irradiated with 150 kHz EMR for 8 weeks. Male fertility indicators, body mass, testicular mass, rectal temperature, testicular histology, histometry, sperm analysis, and serum gonadotrophic hormone levels were evaluated.
Results The study showed no negative effect on body mass (grams) (323.78 ± 37.09 to 305.09 ± 26.36; p = 0.72), rectal temperature (Control: 34.5 °C–35.8 °C; EMR: 34.4 °C–36.1 °C; p < 0.05), and testicular histology. There were significant reductions in left and right testicular mass (1.04 ± 0.10 to 0.96 ± 0.32: p = 0.03 and 1.02 ± 0.08 to 0.96 ± 0.35 p = 0.04, respectively), interstitial cell count/1000 μm2 (5.33 ± 0.56 to 4.47 ± 0.48; p = 0.01), sperm motility trajectories (p = 0.05) and sperm distal cytoplasmic droplet (%) (2.27 ± 2.28 to 6.84 ± 5.01; p = 0.05). A significant increase in follicle-stimulating hormone levels was observed (13.44 ± 6.38 IU/ml to 26.96 ± 8.07 IU/ml; p = 0.01).
Conclusions Most male fertility parameters of rats in the present study were not affected by 8 weeks of whole-body exposure to 150 kHz EMR. However, significant decreases in testicular mass, interstitial cell count/1000 μm2, sperm motility trajectories, and distal cytoplasmic droplets were observed, as well as an increase in FSH level.
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Magnetic fields produced by subsea high-voltage direct current cables
reduce swimming activity of haddock larvae
Cresci A, Durif CMF, Larsen T, Bjelland R, Skiftesvik AB, Browman HI.
Magnetic fields produced by subsea high-voltage direct current cables
reduce swimming activity of haddock larvae (Melanogrammus aeglefinus). PNAS Nexus. 2022 Aug 27;1(4):pgac175. doi: 10.1093/pnasnexus/pgac175.
Abstract
High-voltage direct current (HVDC) subsea cables are used to transport
power between locations and from/to nearshore and offshore facilities.
HVDC cables produce magnetic fields (B-fields) that could impact marine
fish. Atlantic haddock (Melanogrammus aeglefinus) is a demersal
fish that is at risk of exposure to anthropogenic B-fields. Their larvae
drift over the continental shelf, and use the Earth's magnetic field
for orientation during dispersal. Therefore, anthropogenic magnetic
fields from HVDC cables could alter their behavior. We tested the
behavior of 92 haddock larvae using a setup designed to simulate the
scenario of larvae drifting past a B-field in the intensity range of
that produced by a DC subsea cable. We exposed the larvae to a B-field
intensity ranging from 50 to 150 µT in a raceway tank. Exposure to the
B-field did not affect the spatial distribution of haddock larvae in the
raceway. Larvae were categorized by differences in their exploratory
behavior in the raceway. The majority (78%) of larvae were
nonexploratory, and exposure to the artificial B-field reduced their
median swimming speed by 60% and decreased their median acceleration by
38%. There was no effect on swimming of the smaller proportion (22%) of
exploratory larvae. These observations support the conclusion that the
swimming performance of nonexploratory haddock larvae would be reduced
following exposure to B-field from HVDC cables. The selective impact on
nonexploratory individuals, and the lack of impact on exploratory
individuals, could have population-scale implications for haddock in the
wild.
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Magnetic fields generated by submarine power cables have a
negligible effect on the swimming behavior of Atlantic lumpfish
Durif CMF, Nyqvist D, Taormina B, Shema SD, Skiftesvik AB, Freytet F,
Browman HI. Magnetic fields generated by submarine power cables have a
negligible effect on the swimming behavior of Atlantic lumpfish (Cyclopterus lumpus) juveniles. PeerJ. 2023 Jan 23;11:e14745. doi: 10.7717/peerj.14745.
Submarine power cables carry electricity over long distances. Their
geographic distribution, number, and areal coverage are increasing
rapidly with the development of, for example, offshore wind facilities.
The flow of current passing through these cables creates a magnetic
field (MF) that can potentially affect marine organisms, particularly
those that are magnetosensitive. The lumpfish (Cyclopterus lumpus)
is a migratory species that is widely distributed in the North Atlantic
Ocean and Barents Sea. It migrates between coastal spawning grounds and
pelagic offshore feeding areas. We tested whether lumpfish respond to
MFs of the same intensity as those emitted by high voltage direct
current (HVDC) submarine power cables. Laboratory experiments were
conducted by placing juvenile lumpfish in an artificial MF gradient
generated by a Helmholtz coil system. The intensity of the artificial MF
used (230 µT) corresponded to the field at 1 m from a high-power
submarine cable. The fish were filmed for 30 min with the coil either on
or off. Swimming speeds, and presence in the different parts of a
raceway, were extracted from the videos and analyzed. Juvenile lumpfish
activity, defined as the time that the fish spent swimming relative to
stationary pauses (attached to the substrate), and the distance
travelled, were unaffected by exposure to the artificial MF. The
swimming speed of juvenile lumpfish was reduced (by 16%) when the coil
was on indicating that the fish could either sense the MF or the induced
electric field created by the movement of the fish through the magnetic
field. However, it seems unlikely that a 16% decrease in swimming speed
occurring within 1 m of HVDC cables would significantly affect Atlantic
lumpfish migration or homing.
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Geomagnetic disturbance associated
with increased vagrancy in migratory landbirds
Tonelli BA, Youngflesh C, Tingley MW. Geomagnetic disturbance associated
with increased vagrancy in migratory landbirds. Sci Rep. 2023 Jan
9;13(1):414. doi: 10.1038/s41598-022-26586-0.
Abstract
Rare birds known as "accidentals" or "vagrants" have long captivated
birdwatchers and puzzled biologists, but the drivers of these rare
occurrences remain elusive. Errors in orientation or navigation are
considered one potential driver: migratory birds use the Earth's
magnetic field-sensed using specialized magnetoreceptor structures-to
traverse long distances over often unfamiliar terrain. Disruption to
these magnetoreceptors or to the magnetic field itself could potentially
cause errors leading to vagrancy. Using data from 2 million captures of
152 landbird species in North America over 60 years, we demonstrate a
strong association between disruption to the Earth's magnetic field and
avian vagrancy during fall migration. Furthermore, we find that
increased solar activity-a disruptor of the avian
magnetoreceptor-generally counteracts this effect, potentially
mitigating misorientation by disabling the ability for birds to use the
magnetic field to orient. Our results link a hypothesized cause of
misorientation to the phenomenon of avian vagrancy, further
demonstrating the importance of magnetoreception among the orientation
mechanisms of migratory birds. Geomagnetic disturbance may have
important downstream ecological consequences, as vagrants may experience
increased mortality rates or facilitate range expansions of avian
populations and the organisms they disperse.
