Twenty Recent EMF Papers From PowerWatch as of Dec. 2014
1. P Reale
M et al, (August 2014) Neuronal cellular responses to
extremely low frequency electromagnetic field exposure: implications regarding
oxidative stress and neurodegeneration, PLoS One. 2014 Aug 15;9(8):e104973.
doi: 10.1371/journal.pone.0104973. eCollection 2014 [View Author's
abstract conclusions] [View on Pubmed]
Neurodegenerative
diseases comprise both hereditary and sporadic conditions characterized by an
identifying progressive nervous system dysfunction and distinctive
neuopathophysiology. The majority are of non-familial etiology and hence
environmental factors and lifestyle play key roles in their pathogenesis. The
extensive use of and ever increasing worldwide demand for electricity has
stimulated societal and scientific interest on the environmental exposure to low
frequency electromagnetic fields (EMFs) on human health. Epidemiological
studies suggest a positive association between 50/60-Hz power transmission
fields and leukemia or lymphoma development. Consequent to the association
between EMFs and induction of oxidative stress, concerns relating to
development of neurodegenerative diseases, such as Alzheimer disease (AD), have
been voiced as the brain consumes the greatest fraction of oxygen and is
particularly vulnerable to oxidative stress. Exposure to extremely low
frequency (ELF)-EMFs are reported to alter animal behavior and modulate
biological variables, including gene expression, regulation of cell survival,
promotion of cellular differentiation, and changes in cerebral blood flow in
aged AD transgenic mice. Alterations in inflammatory responses have also been
reported, but how these actions impact human health remains unknown. We hence
evaluated the effects of an electromagnetic wave (magnetic field intensity 1
mT; frequency, 50-Hz) on a well-characterized immortalized neuronal cell model,
human SH-SY5Y cells. ELF-EMF exposure elevated the expession of NOS and O2(-),
which were countered by compensatory changes in antioxidant catylase (CAT)
activity and enzymatic kinetic parameters related to CYP-450 and CAT activity.
Actions of ELF-EMFs on cytokine gene expression were additionally evaluated and
found rapidly modified. Confronted with co-exposure to H2O2-induced oxidative
stress, ELF-EMF proved not as well counteracted and resulted in a decline in
CAT activity and a rise in O2(-) levels. Together these studies support the
further evaluation of ELF-EMF exposure in cellular and in vivo preclinical
models to define mechanisms potentially impacted in humans.
Although carried out at a
high field of 1 mT (1000 μT), this work shows important and concerning changes
- even after one hour of exposure. Inducible Nitric Oxide Synthase (iNOS)
levels are statistically doubled which will lead to more oxidative stress on
cells. Transforming growth factor beta (TGFβ) is increased and interleukin 18
(IL18) levels increase, strongly suggesting an inflammatory response to the ELF
EMF exposure. The 1 mT level is only twice the ICNIRP occupational maximum
guidance level and 5 time the general public level. Safety margins for chemical
hazards are typically at least 1000-fold lower than where biological effects
are seen - that would suggest a maxmimum background level of 1 μT or less (as
in Switzerland) instead of the 200 μT current ICNIRP public guidance level.
This paper certainly shows the need for funding further good investigative
work.
2. N Zhang
Y et al, (August 2014) Short term effects of extremely
low frequency electromagnetic fields exposure on Alzheimer's disease in rats,
Int J Radiat Biol. 2014 Aug 13:1-35. [Epub ahead of print] [View Author's
abstract conclusions] [View on Pubmed]
With the development and widespread use of
electromagnetic field (EMF) technology, recent studies are focusing on the
effects of EMF on human health. Recently, extremely low frequency
electromagnetic fields (ELF-EMF) have been studied with great interest due to
their possible effects on Alzheimer's disease (AD). The objective of the
present study was to investigate the interaction between ELF-EMF exposure and
memory impairment in rats. Materials and methods: Twenty healthy male Sprague
Dawley (SD) rats were randomly divided into two groups (n=10). Animals were
exposed to 100 µT/50Hz ELF-EMF or subjected to sham exposure when 12 weeks old.
After 12 weeks, Morris water maze (MWM) was used to test the changes in
cognitive and memory ability. Amyloid-beta (Aβ) content in cortex, hippocampus
and plasma were measured by ELISA assays. The morphology of neuron was detected
by HE staining. Results: After exposure, the body weight of rats showed no
difference compared with control group. The application of ELF-EMF did not
induce any cognitive and memory impairment compared with sham exposure group.
The determination of Aβ showed no significant change between two groups. And
there was no histological change in ELF-EMF exposure group. Conclusion: The
present study indicated that short term exposure of 100 µT/50Hz ELF-EMF had no
effects on cognition and memory of rats, and did not alter the expression of Aβ
and the neuron morphology. However, more comprehensive studies are still
required to elucidate the possible effects and underlying mechanisms of ELF-EMF
exposure on living organisms.
3. P Marjanovic
AM et al, (August 2014) Cell oxidation-reduction
imbalance after modulated radiofrequency radiation, Electromagn Biol Med.
2014 Aug 13:1-6. [Epub ahead of print] [View Author's
abstract conclusions] [View on Pubmed]
The
aim of this study was to evaluate an influence of modulated radiofrequency
field (RF) of 1800 MHz, strength of 30 V/m on oxidation-reduction processes
within the cell. The assigned RF field was generated within Gigahertz
Transversal Electromagnetic Mode cell equipped by signal generator, modulator,
and amplifier. Cell line V79, was irradiated for 10, 30, and 60 min, specific
absorption rate was calculated to be 1.6 W/kg. Cell metabolic activity and
viability was determined by MTT assay. In order to define total protein
content, colorimetric method was used. Concentration of oxidised proteins was
evaluated by enzyme-linked immunosorbent assay. Reactive oxygen species (ROS)
marked with fluorescent probe 2',7'-dichlorofluorescin diacetate were measured
by means of plate reader device. In comparison with control cell samples,
metabolic activity and total protein content in exposed cells did not differ
significantly. Concentrations of carbonyl derivates, a product of protein
oxidation, insignificantly but continuously increase with duration of exposure.
In exposed samples, ROS level significantly (p < 0.05) increased after 10
min of exposure. Decrease in ROS level was observed after 30-min treatment
indicating antioxidant defence mechanism activation. In conclusion, under the
given laboratory conditions, modulated RF radiation might cause impairment in
cell oxidation-reduction equilibrium within the growing cells.
This paper gives potentially
importants pointers as to one way that lots of short term cell phone exposures
with gaps between the (like in normal real-life use) caould seriously damage
cell health and viability. Triggering elevated ROS levels after 10 minutes use
and before cellular defense mechanisms become active.
4. P Chiu
CT et al, (August 2014) Mobile phone use and health
symptoms in children, J Formos Med Assoc. 2014 Aug 9. pii:
S0929-6646(14)00207-1. doi: 10.1016/j.jfma.2014.07.002. [Epub ahead of print] [View Author's
abstract conclusions] [View on Pubmed]
This
study was designed to investigate the mobile phone (MP) use for talking in
relation to health symptoms among 2042 children aged 11-15 years in Taiwan. A
nationwide, cross-sectional study, using the computer assisted telephone
interview (CATI) technique, was conducted in 2009 to collect information on
children's utilization of MPs and the perceived health symptoms reported by
their parents. The overall prevalence of MP use in the past month was estimated
at 63.2% [95% confidence interval (CI) = 61.1-65.3%]. MP use was associated
with a significantly increased adjusted odds ratio (AOR) for headaches and
migraine (1.42, 95% CI = 1.12-1.81) and skin itches (1.84, 95% CI = 1.47-2.29).
Children who regularly used MPs were also considered to have a health status
worse than it was 1 year ago (β = 0.27, 95% CI = 0.17-0.37). Although the
cross-sectional design precludes the causal inference for the observed
association, our study tended to suggest a need for more cautious use of MPs in
children, because children are expected to experience a longer lifetime
exposure to radiofrequency electromagnetic fields (RF-EMF) from MPs.
This paper gives support to
existing evidence that mobile phone use by children can cause adverse health
effects, including headaches amd migraines. The authors state that their
results suggest that a more cautious approach to the use of mobile phones by children
is advisable.
5. P Liu
DD et al, (June 2014) Melatonin protects rat cerebellar
granule cells against electromagnetic field-induced increases in Na(+) currents
through intracellular Ca(2+) release, J Cell Mol Med. 2014
Jun;18(6):1060-70. doi: 10.1111/jcmm.12250. Epub 2014 Feb 18 [View Author's
abstract conclusions] [View on Pubmed]
Although
melatonin (MT) has been reported to protect cells against oxidative damage
induced by electromagnetic radiation, few reports have addressed whether there
are other protective mechanisms. Here, we investigated the effects of MT on
extremely low-frequency electromagnetic field (ELF-EMF)-induced Nav activity in
rat cerebellar granule cells (GCs). Exposing cerebellar GCs to ELF-EMF for 60
min. significantly increased the Nav current (INa ) densities by 62.5%. MT (5
µM) inhibited the ELF-EMF-induced INa increase. This inhibitory effect of MT is
mimicked by an MT2 receptor agonist and was eliminated by an MT2 receptor
antagonist. The Nav channel steady-state activation curve was significantly
shifted towards hyperpolarization by ELF-EMF stimulation but remained unchanged
by MT in cerebellar GC that were either exposed or not exposed to ELF-EMF.
ELF-EMF exposure significantly increased the intracellular levels of
phosphorylated PKA in cerebellar GCs, and both MT and IIK-7 did not reduce the
ELF-EMF-induced increase in phosphorylated PKA. The inhibitory effects of MT on
ELF-EMF-induced Nav activity was greatly reduced by the calmodulin inhibitor
KN93. Calcium imaging showed that MT did not increase the basal intracellular
Ca(2+) level, but it significantly elevated the intracellular Ca(2+) level
evoked by the high K(+) stimulation in cerebellar GC that were either exposed
or not exposed to ELF-EMF. In the presence of ruthenium red, a
ryanodine-sensitive receptor blocker, the MT-induced increase in intracellular
calcium levels was reduced. Our data show for the first time that MT protects
against neuronal INa that result from ELF-EMF exposure through Ca(2+)
influx-induced Ca(2+) release.
This is a very important
confirmation of how important a good melatonin diurnal cycle is to many
protective cellular processes. Another reason to consider dark (WiFi free!)
nights, bright mornings and possibly taking a bed-time melatonin supplement.
6. P Turner
MC et al, (September 2014) Occupational exposure to
extremely low-frequency magnetic fields and brain tumor risks in the INTEROCC
study, Cancer Epidemiol Biomarkers Prev. 2014 Sep;23(9):1863-72. doi:
10.1158/1055-9965.EPI-14-0102. Epub 2014 Jun 16 [View Author's
abstract conclusions] [View on Pubmed]
Occupational
exposure to extremely low-frequency magnetic fields (ELF) is a suspected risk factor
for brain tumors, however the literature is inconsistent. Few studies have
assessed whether ELF in different time windows of exposure may be associated
with specific histologic types of brain tumors. This study examines the
association between ELF and brain tumors in the large-scale INTEROCC study.
Cases
of adult primary glioma and meningioma were recruited in seven countries
(Australia, Canada, France, Germany, Israel, New Zealand, and the United
Kingdom) between 2000 and 2004. Estimates of mean workday ELF exposure based on
a job exposure matrix were assigned. Estimates of cumulative exposure, average
exposure, maximum exposure, and exposure duration were calculated for the
lifetime, and 1-4, 5-9, and 10+ years before the diagnosis/reference date. There
were 3,761 included brain tumor cases (1,939 glioma and 1,822 meningioma) and
5,404 population controls. There was no association between lifetime cumulative
ELF exposure and glioma or meningioma risk. However, there were positive
associations between cumulative ELF 1 to 4 years before the diagnosis/reference
date and glioma [odds ratio (OR) = 90th percentile vs. < 25th percentile,
1.67; 95% confidence interval (CI), 1.36-2.07; PLinear trend < 0.0001], and,
somewhat weaker associations with meningioma (OR = 90th percentile vs. <
25th percentile, 1.23; 95% CI, 0.97-1.57; PLinear trend = 0.02). Results showed
positive associations between ELF in the recent past and glioma. Occupational
ELF exposure may play a role in the later stages (promotion and progression) of
brain tumorigenesis.
This important international
occupational study reports a highly statistically significant confirmation of a
association between recent cumulative ELF EMF (magnetic field) exposure and
diagnosis of malignant glioma brain cancer (which is almost always fatal within
a few years). As brain cancer usually has a long latency time between
initiation and diagnosis, the study results point to ELF EMF being a
promotional factor rather than the primary cause.
7. N van
der Mark M et al, (June 2014) Extremely low-frequency
magnetic field exposure, electrical shocks and risk of Parkinson's disease,
Int Arch Occup Environ Health. 2014 Jun 18. [Epub ahead of print] [View Author's
abstract conclusions] [View on Pubmed]
Previous studies did not provide strong evidence
for an increased Parkinson's disease (PD) risk after exposure to extremely
low-frequency magnetic fields (ELF-MF), but were limited in their scope to
address other exposures related to the use of electricity such as electrical
shocks. We evaluated the associations of PD with exposure to ELF-MF, electrical
shocks and having worked in "electrical occupations". We conducted a
hospital-based case-control study, including 444 PD patients and 876 age- and
sex-matched controls. Occupational histories were collected in telephone
interviews and were linked to job-exposure matrices on ELF-MF exposure and on
electrical shocks. In addition, questions on use of household appliances
involving ELF-MF exposure, experienced electrical shocks and potential
confounders were asked. No association of PD risk with any of the evaluated
exposures related to electricity was observed. We did, however, observe quite
consistently reduced risk estimates across the majority of the exposure
categories explored. Given the results of the previous studies and the absence
of any postulated mechanism, this is unlikely to represent a true protective
effect of ELF-MF or electrical shocks on the occurrence of PD. The results of
this study suggest that no association exists between PD and exposure to
ELF-MF, electrical shocks or having worked in "electrical
occupations".
8. P Alsaeed
I et al, (October 2014) Autism-relevant social
abnormalities in mice exposed perinatally to extremely low frequency
electromagnetic fields, Int J Dev Neurosci. 2014 Oct;37:58-64. doi:
10.1016/j.ijdevneu.2014.06.010. Epub 2014 Jun 23. [View Author's
abstract conclusions] [View on Pubmed]
The incidence of autism spectrum disorders (ASD)
has been rising, but the causes of ASD remain largely unidentified. Collective
data have implicated the increased human exposure to electromagnetic fields
(EMF) in the increasing incidence of ASD. There are established biological
effects of extremely low-frequency (ELF) EMF, but the relation to ASD is not
investigated enough. In this study we examined the effects of perinatal
exposure to ELF EMF on some ASD-relevant behavioral parameters in mice. The EMF
was delivered via a Helmholtz coil pair. Male BALB/C mice were used and divided
into exposed and control groups (n=8 and n=9, respectively). Tests were used to
assess sociability, preference for social novelty, locomotion, anxiety,
exploratory behavior, motor coordination, and olfaction. The examined mice were
all males and exposed to EMF during the last week of gestation and for 7 days
after delivery. The exposed mice demonstrated a lack of normal sociability and
preference for social novelty while maintaining normal anxiety-like behavior,
locomotion, motor coordination, and olfaction. Exposed mice also demonstrated
decreased exploratory activity. We concluded that these results are supportive
of the hypothesis of a causal link between exposure to ELF-EMF and ASD;
however, replications of the study with further tests are recommended.
9. P Zhao
G et al, (September 2014) Relationship between exposure
to extremely low-frequency electromagnetic fields and breast cancer risk: a
meta-analysis, Eur J Gynaecol Oncol. 2014;35(3):264-9 [View Author's
abstract conclusions] [View on Pubmed]
The objective of this study was to
comprehensively analyse the relationship between human exposure to extremely
low frequency electromagnetic fields (ELF-EMFs) and breast cancer and to
discuss the potential risk of ELF-EMFs to human breast cancer. Sixteen research
reports of case-control studies which were published from 2000 to 2007 were
collected. The fixed effect model (FEM) or the random effect model (REM) was
chosen to calculate total ORs depending on the outcomes of the test of
homogeneity (Q test): the subgroup was analyzed with the menopause and the
non-menopause. Sixteen research outcome was ORDL = 1.10, 95% CI = (1.01, 1.20),
the OR(MH) of the non-menopause status group was 1.25, 95% CI = (1.05, 1.49),
the OR(MH) of the menopause status group was OR(MH) = 1.04, 95% CI = (0.93,
1.18). The authors found that ELF-EMFs may be increase the risk of human breast
cancer. The women's exposure to ELF-EMFs may be the risk factor of breast
cancer when they are non-menopausal.
10. P Lee
SK et al, (September 2014) Extremely low frequency
magnetic fields induce spermatogenic germ cell apoptosis: possible mechanism,
Biomed Res Int. 2014;2014:567183. doi: 10.1155/2014/567183. Epub 2014 Jun 15 [View Author's
abstract conclusions] [View on Pubmed]
The energy generated by an extremely low
frequency electromagnetic field (ELF-EMF) is too weak to directly induce
genotoxicity. However, it is reported that an extremely low frequency magnetic
field (ELF-MF) is related to DNA strand breakage and apoptosis. The testes that
conduct spermatogenesis through a dynamic cellular process involving meiosis
and mitosis seem vulnerable to external stress such as heat, MF exposure, and
chemical or physical agents. Nevertheless the results regarding adverse effects
of ELF-EMF on human or animal reproductive functions are inconclusive.
According to the guideline of the International Commission on Non-Ionizing
Radiation Protection (ICNIRP; 2010) for limiting exposure to time-varying MF (1
Hz to 100 kHz), overall conclusion of epidemiologic studies has not
consistently shown an association between human adverse reproductive outcomes
and maternal or paternal exposure to low frequency fields. In animal studies
there is no compelling evidence of causal relationship between prenatal
development and ELF-MF exposure. However there is increasing evidence that
EL-EMF exposure is involved with germ cell apoptosis in testes. Biophysical
mechanism by which ELF-MF induces germ cell apoptosis has not been established.
This review proposes the possible mechanism of germ cell apoptosis in testes
induced by ELF-MF.
11. P Li
C et al, (July 2014) The extremely low-frequency
magnetic field exposure differently affects the AMPAR and NMDAR subunit
expressions in the hippocampus, entorhinal cortex and prefrontal cortex without
effects on the rat spatial learning and memory, Environ Res. 2014 Jul
18;134C:74-80. doi: 10.1016/j.envres.2014.06.025. [Epub ahead of print] [View Author's
abstract conclusions] [View on Pubmed]
In the present study, we investigated the effects
of chronic exposure (14 and 28 days) to a 50Hz, 0.5mT extremely low-frequency
magnetic field (ELF-MF) on the NMDAR and AMPAR subunit expressions and rat
spatial learning and memory. Using the Western blotting method, we found ELF-MF
exposure specifically decreased the expressions of GluA2 in the EC post 28 day
exposure and GluA3 of AMPAR subunits in the PFC after 14 day exposure, while it
did not affect the AMPAR subunit expression in the hippocampus at both time
points. As for NMDAR subunits, 14 day ELF-MF exposure significantly increased
the levels of GluN2A and GluN2B in the hippocampus. Moreover, the levels of
GluN1 and GluN2A were enhanced in the EC and PFC after two weeks of ELF-MF
exposure. Interestingly, 28 day ELF-MF exposure induced a different expression
pattern for NMDAR subunits. The increased GluN2A expression observed at 14 day
post ELF-MF exposure was recovered after prolonged exposure in the hippocampus
and PFC. In the EC, the increased expression of GluN1 achieved to control level
and, specifically, a decrease in GluN2A level was observed. Surprisingly,
neither 14 nor 28 day ELF-MF did affect the rat spatial reference memory as
assessed by water maze. These results indicate that the dynamic and
brain-region specific changes in ionotropic glutamate receptor expression
induced by ELF-MF are insufficient to influence the rat spatial learning
ability.
12. N de
Groot MW et al, (September 2014) Assessment of the
neurotoxic potential of exposure to 50Hz extremely low frequency electromagnetic
fields (ELF-EMF) in naive and chemically stressed PC12 cells,
Neurotoxicology. 2014 Sep;44:358-64. doi: 10.1016/j.neuro.2014.07.009. Epub
2014 Aug 8 [View Author's
abstract conclusions] [View on Pubmed]
Increasing exposure to extremely low frequency
electromagnetic fields (ELF-EMF), generated by power lines and electric
appliances, raises concern about potential adverse health effects of ELF-EMF.
The central nervous system is expected to be particularly vulnerable to ELF-EMF
as its function strongly depends on electrical excitability. We therefore
investigated effects of acute (30min) and sub-chronic (48h) exposure to 50Hz
ELF-EMF on naïve and chemically stressed pheochromocytoma (PC12) cells. The
latter have higher levels of iron and/or reactive oxygen species (ROS) and
display increased vulnerability to environmental insults. Effects of ELF-EMF on
Ca(2+)-homeostasis, ROS production and membrane integrity were assessed using
Fura-2 single cell fluorescence microscopy, H2-DCFDA and CFDA assays,
respectively. Our data demonstrate that acute exposure of naïve PC12 cells to
50Hz ELF-EMF up to 1000µT fails to affect basal or depolarization-evoked
[Ca(2+)]i. Moreover, sub-chronic ELF-EMF exposure up to 1000µT has no
consistent effects on Ca(2+)-homeostasis in naïve PC12 cells and does not
affect ROS production and membrane integrity. Notably, in chemically stressed
PC12 cells both acute and sub-chronic ELF-EMF exposure also failed to exert
consistent effects on Ca(2+)-homeostasis, ROS production and membrane
integrity. Our combined findings thus indicate that exposure to 50Hz ELF-EMF up
to 1000µT, i.e. 10,000 times above background exposure, does not induce
neurotoxic effects in vitro, neither in naïve nor in chemically stressed PC12
cells. Though our data require confirmation, e.g. in developing neuronal cells
in vitro or (developing) animals, it appears that the neurotoxic risk of
ELF-EMF exposure is limited.
13. N Sorahan
T, Mohammed N, (September 2014) Neurodegenerative disease and
magnetic field exposure in UK electricity supply workers, Occup Med (Lond).
2014 Sep;64(6):454-60. doi: 10.1093/occmed/kqu105. Epub 2014 Aug 7 [View Author's abstract
conclusions] [View on Pubmed]
Previous research has suggested a possible link
between neurodegenerative disease and exposure to extremely low-frequency
electric and magnetic fields. To investigate whether risks of Alzheimer's,
motor neurone or Parkinson's disease are related to occupational exposure to
magnetic fields. The mortality experienced by a cohort of 73051 employees of
the former Central Electricity Generating Board of England and Wales was
investigated for the period 1973-2010. All employees were hired in the period
1952-82, were employed for at least 6 months and had some employment after 1
January 1973. Detailed calculations had been performed by others to enable an
assessment to be made of exposures to magnetic fields. Poisson regression was
used to calculate relative risks (rate ratios) of developing any of the three
diseases under investigation for categories of lifetime, distant (lagged) and
recent (lugged) exposure. No statistically significant trends were shown for
risks of any of these diseases to increase with estimates of lifetime, recent
or distant exposure to magnetic fields. There is no convincing evidence that UK
electricity generation and transmission workers have suffered elevated risks
from neurodegenerative diseases as a consequence of exposure to magnetic
fields.
14. P Seifirad
S et al, (August 2014) Effects of extremely low
frequency electromagnetic fields on paraoxonase serum activity and lipid
peroxidation metabolites in rat, J Diabetes Metab Disord. 2014 Aug
13;13(1):85. doi: 10.1186/s40200-014-0085-2. eCollection 2014 [View Author's
abstract conclusions] [View on Pubmed]
Atherogenic effects of ELF-MF exposure have not
been studied well so far. Therefore we have hypothesized that ELF-MF exposure
might have atherogenic effect by impairing antioxidant function and increasing
lipid peroxidation. This study was therefore undertaken to examine the effects
of ELF-MF on paraoxonase (PON) activity, antioxidant capacity and lipid
peroxidation metabolites. Effects of time on remodeling of antioxidant system
were also investigated in this study. Seventy five Wistar rats were randomly
allocated into five groups as follows: 1) Sham exposure, 2) Single exposure to
60 Hz, sacrificed immediately after exposure, 3) Single exposure to 60 Hz,
sacrificed 72 hours after exposure, 4) Fourteen days of exposure to 60 Hz,
sacrificed immediately after exposure, and 5) Fourteen days of exposure to 60
Hz, sacrificed 72 hours after exposure. Blood samples were collected and
analyzed. The results were compared using ANOVA and post hoc Tukey HSD for
multiple caparisons. Single ELF-MF exposure significantly increased lipid
peroxidation (CD and MDA) and increased antioxidant serum activity (HDL,
paraoxonase activity, and serum total antioxidant capacity). Chronic ELF-MF exposure
increased lipid peroxidation and affected antioxidant system. Free fatty acids
levels were significantly increased after both single and two weeks exposure.
Chronic exposure led to irreversible changes while acute exposure tended to
reversible alterations on above mentioned parameters. According to the results
of this study, ELF-MF exposure could impair oxidant-antioxidant function and
might increase oxidative stress and lipid peroxidation. Antioxidant capability
was dependent on the duration and continuity of ELF-MF exposure.
15. P Zhu
H et al, (August 2014) Effects of extremely low
frequency electromagnetic fields on human fetal scleral fibroblasts,
Toxicol Ind Health. 2014 Aug 21. pii: 0748233714545837. [Epub ahead of print] [View Author's
abstract conclusions] [View on Pubmed]
This
study investigated the effects of extremely low frequency electromagnetic
fields (ELF-EMFs) on human fetal scleral fibroblasts (HFSFs). HFSFs were
subjected to 50 Hz artificial ELF-EMFs generated by Helmholtz coils with 0.1,
0.2, 0.5, and 1.0 mT field intensities for 6 to 48 h. The viability and factors
involved in scleral structuring of HFSFs were determined. The growth rate of
HFSFs significantly decreased after only 24 h of exposure to ELF-EMFs (0.2 mT).
The messenger RNA (mRNA) expression of collagen type I (COL1A1) decreased and
expression of matrix metalloproteinase-2 (MMP-2) increased significantly. There
was a decrease in tissue inhibitor of MMP-2 mRNA levels between treated and
control cells only at the 1.0 mT intensity level. Transforming growth factor
beta-2 mRNA increased in exposed cells, and, simultaneously, fibroblast growth
factor-2 mRNA levels decreased. The protein expressions of COL1A1 and MMP-2
were also significantly altered subsequent to exposure (p < 0.05). This
study shows that ELF-EMFs had biological effects on HFSFs and could cause
abnormality in scleral collagen.
This study shows significant
adverse ELF magnetic fields effects in foetal connective tissue cells at levels
about half that allowed by the UK's Punblic Health England (HPA) and equal to
the current ICNIRP permitted level. It provides yet more scientific evidence
that current ELF EMF guidance levels are set too high. A reduction by at least
a factor of 10 would be expected for protection from chemical hazards - to
about 10 to 20 microteslas.
16. - Vila
J et al, (June 2014) Development of a source-based approach
to assessing occupational exposure to electromagnetic fields in the INTEROCC
study Development of a source-based approach to assessing occupational exposure
to electromagnetic fields in the INTEROCC study, Occup Environ Med. 2014
Jun;71 Suppl 1:A35-6. doi: 10.1136/oemed-2014-102362.110 [View Author's
abstract conclusions] [View on Pubmed]
Exposure
to electromagnetic fields (EMF) has become ubiquitous in modern life and
concern has increased regarding possible associated health effects. To date,
assessment of occupational exposure has relied on job-exposure matrices, with
exposure estimates for very broad occupational categories. To move EMF research
forward, a new approach was necessary. A source-based strategy, incorporating
detailed information on tasks, equipment used and work organisation could allow
a more individualised exposure assessment. Information on occupational
histories and sources of EMF was collected as part of the INTERPHONE-INTEROCC
study, providing an opportunity to assess occupational EMF exposure by
assigning exposure to each source used. A source-exposure matrix (SEM) was developed
based on measurements identified in the literature and estimates obtained
through experts' elicitation, for sources without available measurements. This
paper focuses on the SEM development methodology to ensure the quality and
representativeness of the estimates. Estimates of exposure for 138 EMF sources
were obtained from measurements (1424 aggregated records) extracted from 71
papers and hygiene reports (1974-2013). For each source, exposure was
calculated by frequency band and dosimetry type, as the arithmetic and
geometric means of all measurements identified. Standard deviations were
included in order to characterise the variability of the estimates. A
source-exposure matrix has been constructed for the most common sources of EMF
in the workplace, based on the responses to the INTERPHONE-INTEROCC study
questionnaire. This database currently represents the most comprehensive source
of information on occupational EMF exposure and is available on request to
researchers.
A lot of work went into this
work which was necessary for the INTEROCC study. However, electrical and
electronic equipment design and manufacturing techniques have changed
enormously over this time period (1974-2013). Most measurements would have been
unlikely to assess VLF fields from equipment, and the way ELF fields fall off
with distance has changed considerably for a great deal of electrical equipment
(e.g. the change from transformers to switched-mode power supplies and from
50/60 Hz synchronous motors to variable frequency electronically switched
drives). We have not seen the database contents yet, but it should be treated
with caution, especially as to how it applies to recent exposures.
17. P Isaac
Aleman E et al, (September 2014) Effects of 60 Hz
sinusoidal magnetic field on in vitro establishment, multiplication, and
acclimatization phases of Coffea arabica seedlings, Bioelectromagnetics.
2014 Sep;35(6):414-25. doi: 10.1002/bem.21859. Epub 2014 Jul 17 [View Author's
abstract conclusions] [View on Pubmed]
The
influence of extremely low frequency electromagnetic fields on net
photosynthesis, transpiration, photosynthetic pigment concentration, and gene
expression of ribulose 1,5-bisphosphate carboxylase/oxygenase small subunit
(RBCS1), during in vitro establishment, in vitro multiplication and
acclimatization phases of coffee seedlings were investigated. Untreated coffee
plants were considered as control, whereas treated plants were exposed to a 60
Hz sinusoidal magnetic field of 2 mT of magnetic induction during 3 min. This
magnetic field was generated by an electromagnet, connected to a wave generator.
The results revealed that magnetically treated plants showed a significant
increase in net photosynthesis (85.4% and 117.9%, in multiplication and
acclimatization phases, respectively), and in photosynthetic pigment
concentration (66.6% for establishment phase, 79.9% for multiplication phase,
and 43.8% for acclimatization phase). They also showed a differential RBCS1
gene expression (approximately twofold) and a decrease of transpiration rates
in regard to their control plants. In conclusion, the findings suggest that the
application of 60 Hz magnetic field to in vitro coffee plants may improve the
seedlings quality by modifying some photosynthetic physiological and molecular
processes, increasing their vigor, and ensuring better plant development in
later stages.
An interesting paper showing
that short-term (3 minutes) exposure to high levels (2 mT) ELF magnetic fields
stimulates seedlings in a positive way. The work should be repeated at 100, 200
and 500 microtesla levels so that it can be related to permitted human general
public exposure levels.
18. P Jung
IS et al, (October 2014) Effects of extremely low
frequency magnetic fields on NGF induced neuronal differentiation of PC12 cells,
Bioelectromagnetics. 2014 Oct;35(7):459-69. doi: 10.1002/bem.21861. Epub 2014
Aug 26 [View Author's
abstract conclusions] [View on Pubmed]
Extremely low-frequency magnetic fields (ELF-MFs)
affect various cellular processes and systems, such as cell proliferation,
differentiation and metabolic pathways. The present study investigated ELF-MFs
effect on nerve growth factor (NGF) induced neuronal differentiation of PC12
cells using proteomic applications to understand its role in the enhancement of
neuronal differentiation. After 50 Hz, 1 mT ELF-MFs 5-day exposure on NGF
induced PC12 cells, it was observed to increase neurite length as well as an
increase in the number of neurite bearing cells. It was also discovered that
there was a decrease in proliferation activity, which is associated with an
increase in differentiated cells. Neuronal differentiation related mRNA levels
and protein levels were increased in NGF induced PC12 cells. Compared with NGF
induced group, ELF-MFs stimulated PC12 cells had different protein expression
as measured with two-dimensional electrophoresis (2-DE) gels. Consequently six
differentially expressed spots were detected between the 2-DE maps, which were
identified by electrospray ionization quadrupole time-of-flight tandem mass
spectrometry (ESI-Q-TOF LC/MS/MS) as: peripherin, neurosecretory protein nerve
growth factor inducible (VGF8a) precursor, dnaK-type molecular chaperone
sp72-ps1 (HSP72-psI), low molecular weight (Mr) phosphotyrosine protein
phosphatase isoenzyme AcP1 (LMW-PTP/ACP1), Tubulin alpha-1A (TUBA1A) chain,
outcome predictor in acute leukemia 1 homolog (OPA1L). The identification of
these proteins provides clues to the mechanism of ELF-MFs stimulation on NGF
induced PC12 cells that occur during neuronal differentiation and may
contribute to the development novel treatments for neurodegenerative diseases.
19. - Calvente
I et al, (September 2014) Characterization of Indoor
Extremely Low Frequency and Low Frequency Electromagnetic Fields in the
INMA-Granada Cohort, PLoS One. 2014 Sep 5;9(9):e106666. doi:
10.1371/journal.pone.0106666. eCollection 2014 [View Author's
abstract conclusions] [View on Pubmed]
The objective of this study was to characterize
the exposure to electric fields and magnetic fields of non-ionizing radiation
in the electromagnetic spectrum (15 Hz to 100 kHz) in the dwellings of children
from the Spanish Environment and Childhood-"INMA" population-based
birth cohort. The study sample was drawn from the INMA-Granada cohort. Out of
300 boys participating in the 9-10 year follow-up, 123 families agreed to the
exposure assessment at home and completed a specific ad hoc questionnaire
gathering information on sources of non-ionizing radiation electric and
magnetic fields inside the homes and on patterns of use. Long-term indoor
measurements were carried out in the living room and bedroom. Survey data
showed a low exposure in the children's homes according to reference levels of
the International Commission on Non-Ionizing Radiation Protection but with
large differences among homes in mean and maximum values. Daytime electrostatic
and magnetic fields were below the quantification limit in 78.6% (92 dwellings)
and 92.3% (108 dwellings) of houses, with an arithmetic mean value (± standard
deviation) of 7.31±9.32 V/m and 162.30±91.16 nT, respectively. Mean magnetic
field values were 1.6 lower during the night than the day. Nocturnal
electrostatic values were not measured. Exposure levels were influenced by the
area of residence (higher values in urban/semi-urban versus rural areas), type
of dwelling, age of dwelling, floor of the dwelling, and season. Given the
greater sensitivity to extremely low-frequency electromagnetic fields of
children and following the precautionary principle, preventive measures are
warranted to reduce their exposure.
20. - Kim
BC et al, (September 2014) Evaluation of radiofrequency
exposure levels from multiple wireless installations in population dense areas
in Korea, Bioelectromagnetics. 2014 Sep 4. doi: 10.1002/bem.21874. [Epub
ahead of print] [View Author's
abstract conclusions] [View on Pubmed]
This paper presents the results of measurements
from simultaneous human exposure to various radiofrequency (RF) signals at
densely populated areas. Measurements were performed at 1260 positions across
Korea to determine exposure compliance to electromagnetic fields for the
general public. The measured exposure levels were very low compared with the
international exposure guidelines and Korean human protection notice. The
highest total exposure ratio was 5.1 x 10-3 (approximately 7.1% of guideline
limits).
No comments:
Post a Comment