Unknown authors · 2010
Early studies tended toward a consistent association between risks for leukemia and brain cancer and residential proximity to power lines having high wire configuration. More recent studies using improved exposure measurement methods have produced inconsistent results, with some suggesting increased risk and others not. Occupational exposures suggested increased risk for leukemia and to a lesser extent brain cancer and Non-Hodgkin lymphoma. Studies of residential exposures and cancer in adults generally suggested no effect. Laboratory work has been unable to demonstrate a biological mechanism that might explain the epidemiological findings.
Unknown authors · 2010
Unknown authors · 2010
Researchers tested alternative dose-response relationships quantitatively using five exposure data sets and three epidemiological data sets. Threshold dose-response relationships performed only moderately. Linear relationships were generally even poorer. The fit was improved by adding quadratic terms or performing non-linear regression.
Unknown authors · 2010
The study analyzed live singleton births in Montréal and Québec from 1990 to 2004 using the Québec birth file. Proximity was defined as residing within 400 meters of a transmission line, and generalized estimating equations assessed associations with preterm birth, low birth weight, small-for-gestational-age birth, and infant sex while adjusting for maternal and neighborhood factors. No association was found for preterm birth, low birth weight, or infant sex, but a lower likelihood of small-for-gestational-age birth appeared for some distance categories such as 50–75 meters compared to 400 meters or more.
Unknown authors · 2010
The systematic review analyzed publications from 1979 to 2008 on the association between environmental non-ionizing radiation exposure and childhood leukemia risk. The review concluded that studies have not convincingly confirmed or ruled out an association. Discrepancies among study conclusions may be influenced by confounding factors, selection bias, and misclassification. The authors state an urgent need to reconsider exposure limits for low frequency and static magnetic fields based on combined experimental and epidemiological research.
Unknown authors · 2010
The group used early chick embryos and L929 and Daudi cells as experimental systems. The review found that ELF magnetic noise fields inhibited the effects when they were observed, and in all cases where a noise field was applied to prevent an observed effect it eliminated the effect.
Unknown authors · 2010
Researchers exposed male Wistar rats from postnatal day 23 to 53 to 50 Hz magnetic fields at 100-300 μT for 4 hours daily, atrazine at 20 or 200 mg/kg body weight, or both combined. Light and electron microscopy showed no significant alterations in thyroid structure in any treated group compared to controls. The magnetic field group showed significant differences in thyroid follicle volume density and connective tissue compared to atrazine and combined groups. High-dose atrazine significantly affected mast cell numbers compared to controls.
Unknown authors · 2010
Kroll et al based their analysis on data from Draper et al and used a refined exposure measure based on field calculations. Draper et al reported a significantly elevated odds ratio of 1.69 for persons living within 200 m of power lines compared with those beyond 600 m. Kroll et al found an odds ratio of 2.0 for the highest exposure group (≥0.4 vs <0.1 μT) but the result was not statistically significant. Field calculations were not possible for 25% of addresses near power lines.
Unknown authors · 2010
Researchers conducted a national case-control study of children born in England and Wales from 1962 to 1995 to examine cancer risk from magnetic fields of high-voltage overhead power lines at the birth address. The estimated relative risk for each 0.2 μT increase was 1.14 for leukaemia, 0.80 for CNS/brain tumours, and 1.34 for other cancers, with confidence intervals that included no effect. The researchers concluded that magnetic-field exposure during the year of birth is unlikely to be the whole cause of the association with distance from overhead power lines that they previously reported.
Unknown authors · 2010
Researchers pooled primary data from studies published after 2000, including 10 865 cases and 12 853 controls. The main analysis focused on 24-h magnetic field measurements or calculated fields in residences. In the combined results, risk increased with higher exposure, but the estimates were imprecise, with odds ratios of 1.07 for 0.1–0.2 μT, 1.16 for 0.2–0.3 μT, and 1.44 for 0.3 μT or higher compared to <0.1 μT. When the most influential study from Brazil was excluded, the odds ratios increased somewhat. A nonparametric analysis also suggested an increasing trend.
Unknown authors · 2010
Researchers examined 9,508 individuals from the Study of Dementia in Swedish Twins to assess the association between occupational extremely low-frequency magnetic field exposure and dementia risk. Dementia diagnoses were based on telephone screening followed by in-person clinical workup, and main lifetime occupation was coded using an established EMF exposure matrix. Overall EMF exposure level was not significantly associated with dementia or Alzheimer's disease. However, in stratified analyses, medium and high EMF exposure were associated with increased dementia risk compared with low exposure in cases with onset by age 75 years and in participants with manual occupations. Results from 42 twin pairs discordant for dementia did not reach statistical significance.
Unknown authors · 2010
Researchers applied Bradford-Hill criteria and a European Commission precautionary framework to evaluate the link between childhood leukemia and power frequency magnetic fields. The main evidence is an epidemiological association from several studies and meta-analyses, though few children are highly exposed and the association could reflect bias, confounding, or chance. Experimental evidence does not clearly show harm at the implicated field levels, and the cause of childhood leukemia is poorly understood. A precautionary approach recommends low-cost interventions to reduce exposure, assuming any real risk would be small, but the recommendation is controversial because other data interpretations exist and low-cost measures may not fully alleviate the risk.
Unknown authors · 2010
A case-control study in southwestern France from May 1999 to April 2001 included 221 adults with central nervous system tumors and 442 matched controls. Occupational ELF and radiofrequency exposure was assessed by expert judgment using job calendars, and residential exposure by distance to power lines via a geographic information system. Occupational ELF exposure showed a significant increase in meningioma risk (OR=3.02, 95% CI 1.10-8.25), while living within 100 m of power lines gave a non-significant increase (OR=2.99, 95% CI 0.86-10.40).
Unknown authors · 2010
The present study investigated the potential effects of extremely low frequency (ELF) electric field exposure on plasma cholesterol and triglyceride levels of adult male rats. Sixty rats were randomly divided into three groups: controls without exposure, a group exposed to 50 Hz for 10 days, and a group exposed to 50 Hz for 30 days. Total cholesterol concentration in the short-term exposure group was 65.33 ± 15.31 mg/dL and in the long-term exposure group was 59.55 ± 15.01 mg/dL, both significantly lower than the control value of 70.44 ± 19.60 mg/dL. Plasma triglyceride levels were 67.33 ± 15.63 mg/dL in one exposed group and 51.53 ± 14.17 mg/dL in the other, compared with 84.44 ± 16.79 mg/dL in controls.
Unknown authors · 2010
Researchers conducted a measurement campaign aboard Italian main line trains to assess railway workers' exposure to static and ELF magnetic fields. Measurements were taken during regular service with two engine drivers present, in all accessible areas, across routes from tens to hundreds of kilometres. The protocol used broadband metres and personal metres for individual exposure assessment across seven different engine or train models. Traction motors were fed by AC current except for two engines where AC powered only auxiliary services. Average static field exposure was slightly above background geomagnetic levels, occasionally reaching millitesla, while average ELF exposure was 1-2 μT with hot spots near wiring reaching tens of microtesla.
Unknown authors · 2010
Previous epidemiological studies of radiofrequency electromagnetic fields relied on crude exposure proxies like job titles and equipment use. The Royal Norwegian Navy measured RF fields from antennas and radars at crew locations on fast patrol boats. The boats are small, placing crew close to RF-emitting equipment. Researchers described the measured exposure and proposed calculation methods using linear and spatial averages, percentage of ICNIRP, and squared deviation of ICNIRP.
Unknown authors · 2010
Unknown authors · 2010
Researchers extended a Wi-Fi power model to account for devices that do not always have packets to transmit. They validated the model using testbed measurements and found relative errors of less than 5-10%. The greatest power emission occurred when the network was saturated with traffic, enabling a simple technique to estimate power output from traffic levels.
Unknown authors · 2010
The EEIF is a global parameter representing electromagnetic impact on a specific area from radiating systems like base station antennas. Its numerical value depends only on electromagnetic field intensity, which can be measured or computed. The paper describes field distribution parameters and assumptions for the EEIF scale, and applies the method to real urban situations.
Unknown authors · 2010
Researchers exposed male mice to radiofrequency radiations from GSM base stations at a workplace complex and residential quarters. Exposed mice showed 39.78% and 46.03% sperm head abnormalities compared to 2.13% in controls. The increase was statistically significant and dose dependent, with major abnormalities including knobbed hook, pin-head, and banana-shaped sperm heads.
Unknown authors · 2010
The review states that everyone is exposed to electromagnetic fields from electricity, communication frequencies, and wireless devices. Strong evidence has linked leukemia to residential or occupational exposure to extremely low frequency EMFs for many years. Current ELF standards are not sufficiently stringent to protect against increased cancer risk. Radiofrequency standards are set to avoid tissue heating despite evidence of adverse biological effects at lower intensities. Recent studies show elevations in brain cancer and acoustic neuroma on the side of the head where cell phones were used.
Unknown authors · 2010
Unknown authors · 2010
Mobile phone use is increasing extraordinarily rapidly worldwide, with 4.6 billion subscribers. Users of mobile phones are exposed to electromagnetic radiation that has long been hypothesized to have adverse health effects, including increased cancer risk. Research on biological mechanisms of cellular and tissue injury by electromagnetic radiation has been inconclusive, making epidemiological studies the principal source of evidence on potential health risks of mobile phone use. Brain tumours have been of particular concern because radiation from phones passes through the brain when used without a hands-free device, but previous studies have shown mixed findings with no clear indication of increased cancer risk.
Unknown authors · 2010
Researchers analyzed brain tumor data from 2000-2004 and 2007 cell phone subscription data. They found a strong correlation between cell phone subscriptions and brain tumor incidence (r = 0.950, P < 0.001). Multiple linear regression showed the association remained significant after controlling for population, mean family income, and mean age (P = 0.017). The authors considered the linear relationship disturbing and called for further epidemiological evaluation. They suggested it would be prudent to limit exposure to all sources of electromagnetic radiation.
Unknown authors · 2010
