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Eduardo G Moros - One of the best experts on this subject based on the ideXlab platform.
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chromosome damage and micronucleus formation in human blood lymphocytes exposed in vitro to radiofrequency radiation at a Cellular Telephone frequency 847 74 mhz cdma
Radiation Research, 2001Co-Authors: Kheem S Bisht, Martin L. Meltz, William F Pickard, Joseph Roti L Roti, Eduardo G MorosAbstract:Abstract Vijayalaxmi, Bisht, K. S., Pickard, W. F., Meltz, M. L., Roti Roti, J. L. and Moros, E. G. Chromosome Damage and Micronucleus Formation in Human Blood Lymphocytes Exposed In Vitro to Radiofrequency Radiation at a Cellular Telephone Frequency (847.74 MHz, CDMA). Radiat. Res. 156, 430–432 (2001). Peripheral blood samples collected from four healthy nonsmoking human volunteers were diluted with tissue culture medium and exposed in vitro for 24 h to 847.74 MHz radiofrequency (RF) radiation (continuous wave), a frequency employed for Cellular Telephone communications. A code division multiple access (CDMA) technology was used with a nominal net forward power of 75 W and a nominal power density of 950 W/m2 (95 mW/cm2). The mean specific absorption rate (SAR) was 4.9 or 5.5 W/kg. Blood aliquots that were sham-exposed or exposed in vitro to an acute dose of 1.5 Gy of γ radiation were included in the study as controls. The temperatures of the medium during RF-radiation and sham exposures in the Radial Tra...
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cytogenetic studies in human blood lymphocytes exposed in vitro to radiofrequency radiation at a Cellular Telephone frequency 835 62 mhz fdma
Radiation Research, 2001Co-Authors: William F Pickard, Martin L. Meltz, Kheem S Bisht, Joseph Roti L Roti, Belinda Z Leal, William Straube, Eduardo G MorosAbstract:Freshly collected peripheral blood samples from four healthy human volunteers were diluted with RPMI 1640 tissue culture medium and exposed in sterile T-75 tissue culture flasks in vitro for 24 h to 835.62 MHz radiofrequency (RF) radiation, a frequency employed for customer-to-base station transmission of Cellular Telephone communications. An analog signal was used, and the access technology was frequency division multiple access (FDMA, continuous wave). A nominal net forward power of 68 W was used, and the nominal power density at the center of the exposure flask was 860 W/m(2). The mean specific absorption rate in the exposure flask was 4.4 or 5.0 W/kg. Aliquots of diluted blood that were sham-exposed or exposed in vitro to an acute dose of 1.50 Gy of gamma radiation were used as negative or positive controls. Immediately after the exposures, the lymphocytes were stimulated with a mitogen, phytohemagglutinin, and cultured for 48 or 72 h to determine the extent of genetic damage, as assessed from the frequencies of chromosomal aberrations and micronuclei. The extent of alteration in the kinetics of cell proliferation was determined from the mitotic indices in 48-h cultures and from the incidence of binucleate cells in 72-h cultures. The data indicated no significant differences between RF-radiation- and sham-exposed lymphocytes with respect to mitotic indices, incidence of exchange aberrations, excess fragments, binucleate cells, and micronuclei. In contrast, the response of the lymphocytes exposed to gamma radiation was significantly different from both RF-radiation- and sham-exposed cells for all of these indices. Thus, under the experimental conditions tested, there is no evidence for the induction of chromosomal aberrations and micronuclei in human blood lymphocytes exposed in vitro for 24 h to 835.62 MHz RF radiation at SARs of 4.4 or 5.0 W/kg.
Hugh S Taylor - One of the best experts on this subject based on the ideXlab platform.
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correction corrigendum fetal radiofrequency radiation exposure from 800 1900 mhz rated Cellular Telephones affects neurodevelopment and behavior in mice
Scientific Reports, 2013Co-Authors: Tamir S Aldad, Geliang Gan, Xiaobing Gao, Hugh S TaylorAbstract:Neurobehavioral disorders are increasingly prevalent in children, however their etiology is not well understood. An association between prenatal Cellular Telephone use and hyperactivity in children has been postulated, yet the direct effects of radiofrequency radiation exposure on neurodevelopment remain unknown. Here we used a mouse model to demonstrate that in-utero radiofrequency exposure from Cellular Telephones does affect adult behavior. Mice exposed in-utero were hyperactive and had impaired memory as determined using the object recognition, light/dark box and step-down assays. Whole cell patch clamp recordings of miniature excitatory postsynaptic currents (mEPSCs) revealed that these behavioral changes were due to altered neuronal developmental programming. Exposed mice had dose-responsive impaired glutamatergic synaptic transmission onto layer V pyramidal neurons of the prefrontal cortex. We present the first experimental evidence of neuropathology due to in-utero Cellular Telephone radiation. Further experiments are needed in humans or non-human primates to determine the risk of exposure during pregnancy.
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fetal radiofrequency radiation exposure from 800 1900 mhz rated Cellular Telephones affects neurodevelopment and behavior in mice
Scientific Reports, 2012Co-Authors: Tamir S Aldad, Geliang Gan, Xiaobing Gao, Hugh S TaylorAbstract:Neurobehavioral disorders are increasingly prevalent in children, however their etiology is not well understood. An association between prenatal Cellular Telephone use and hyperactivity in children has been postulated, yet the direct effects of radiofrequency radiation exposure on neurodevelopment remain unknown. Here we used a mouse model to demonstrate that in-utero radiofrequency exposure from Cellular Telephones does affect adult behavior. Mice exposed in-utero were hyperactive and had impaired memory as determined using the object recognition, light/dark box and step-down assays. Whole cell patch clamp recordings of miniature excitatory postsynaptic currents (mEPSCs) revealed that these behavioral changes were due to altered neuronal developmental programming. Exposed mice had dose-responsive impaired glutamatergic synaptic transmission onto layer V pyramidal neurons of the prefrontal cortex. We present the first experimental evidence of neuropathology due to in-utero Cellular Telephone radiation. Further experiments are needed in humans or non-human primates to determine the risk of exposure during pregnancy.
Robert Tibshirani - One of the best experts on this subject based on the ideXlab platform.
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interpretation and bias in case crossover studies
Journal of Clinical Epidemiology, 1997Co-Authors: Donald A Redelmeier, Robert TibshiraniAbstract:The case-crossover design is an innovative epidemiologic technique with distinct strengths and limitations. We review the fundamental logic of this self-matching non-randomized design and direct attention to 15 concerns related to the available data, unavailable data, analytic technique, quantitative statistics, and etiologic model. Implications for each concern are discussed in the context of a recent report on whether Cellular Telephone calls are associated with an increased risk of a motor vehicle collision. We suggest that an understanding of the case-crossover design may help investigators explore selected questions in behavioral medical research.
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association between Cellular Telephone calls and motor vehicle collisions
The New England Journal of Medicine, 1997Co-Authors: Donald A Redelmeier, Robert TibshiraniAbstract:Background Because of a belief that the use of Cellular Telephones while driving may cause collisions, several countries have restricted their use in motor vehicles, and others are considering such regulations. We used an epidemiologic method, the case–crossover design, to study whether using a Cellular Telephone while driving increases the risk of a motor vehicle collision. Methods We studied 699 drivers who had Cellular Telephones and who were involved in motor vehicle collisions resulting in substantial property damage but no personal injury. Each person's Cellular-Telephone calls on the day of the collision and during the previous week were analyzed through the use of detailed billing records. Results A total of 26,798 Cellular-Telephone calls were made during the 14-month study period. The risk of a collision when using a Cellular Telephone was four times higher than the risk when a Cellular Telephone was not being used (relative risk, 4.3; 95 percent confidence interval, 3.0 to 6.5). The relative ri...
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association between Cellular Telephone calls and motor vehicle collisions
The New England Journal of Medicine, 1997Co-Authors: Donald A Redelmeier, Robert TibshiraniAbstract:BACKGROUND: Because of a belief that the use of Cellular Telephones while driving may cause collisions, several countries have restricted their use in motor vehicles, and others are considering such regulations. We used an epidemiologic method, the case-crossover design, to study whether using a Cellular Telephone while driving increases the risk of a motor vehicle collision. METHODS: We studied 699 drivers who had Cellular Telephones and who were involved in motor vehicle collisions resulting in substantial property damage but no personal injury. Each person's Cellular-Telephone calls on the day of the collision and during the previous week were analyzed through the use of detailed billing records. RESULTS: A total of 26,798 Cellular-Telephone calls were made during the 14-month study period. The risk of a collision when using a Cellular Telephone was four times higher than the risk when a Cellular Telephone was not being used (relative risk, 4.3; 95 percent confidence interval, 3.0 to 6.5). The relative risk was similar for drivers who differed in personal characteristics such as age and driving experience; calls close to the time of the collision were particularly hazardous (relative risk, 4.8 for calls placed within 5 minutes of the accident, as compared with 1.3 for calls placed more than 15 minutes before the accident; P<0.001); and units that allowed the hands to be free (relative risk, 5.9) offered no safety advantage over hand-held units (relative risk, 3.9; P not significant). Thirty-nine percent of the drivers called emergency services after the collision, suggesting that having a Cellular Telephone may have had advantages in the aftermath of an event. CONCLUSIONS: The use of Cellular Telephones in motor vehicles is associated with a quadrupling of the risk of a collision during the brief time interval involving a call. Decisions about regulation of such Telephones, however, need to take into account the benefits of the technology and the role of individual responsibility.
Christoffer Johansen - One of the best experts on this subject based on the ideXlab platform.
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Cellular Telephone Use and Cancer Risk: Update of a Nationwide Danish Cohort
Journal of the National Cancer Institute, 2006Co-Authors: Joachim Schuz, Rune Jacobsen, Jørgen H. Olsen, John D. Boice, Joseph K. Mclaughlin, Christoffer JohansenAbstract:Background: The widespread use of Cellular Telephones has heightened concerns about possible adverse health effects. The objective of this study was to investigate cancer risk among Danish Cellular Telephone users who were followed for up to 21 years. Methods: This study is an extended follow-up of a large nationwide cohort of 420 095 persons whose fi rst Cellular Telephone subscription was between 1982 and 1995 and who were followed through 2002 for cancer incidence. Standardized incidence ratios (SIRs) were calculated by dividing the number of observed cancer cases in the cohort by the number expected in the Danish population. Results: A total of 14 249 cancers were observed (SIR = 0.95; 95% confi dence interval [CI] = 0.93 to 0.97) for men and women combined. Cellular Telephone use was not associated with increased risk for brain tumors (SIR = 0.97), acoustic neuromas (SIR = 0.73), salivary gland tumors (SIR = 0.77), eye tumors (SIR = 0.96), or leukemias (SIR = 1.00). Among long-term subscribers of 10 years or more, Cellular Telephone use was not associated with increased risk for brain tumors (SIR = 0.66, 95% CI = 0.44 to 0.95), and there was no trend with time since fi rst subscription. The risk for smoking-related cancers was decreased among men (SIR = 0.88, 95% CI = 0.86 to 0.91) but increased among women (SIR = 1.11, 95% CI = 1.02 to 1.21). Additional data on income and smoking prevalence, primarily among men, indicated that Cellular Telephone users who started subscriptions in the mid-1980s appeared to have a higher income and to smoke less than the general population. Conclusions: We found no evidence for an association between tumor risk and Cellular Telephone use among either short-term or longterm users. Moreover, the narrow confi dence intervals provide evidence that any large association of risk of cancer and Cellular Telephone use can be excluded. [J Natl Cancer Inst 2006;98: 1707 – 13 ]
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Cellular Telephone use and risk of acoustic neuroma
American Journal of Epidemiology, 2004Co-Authors: Helle Collatz Christensen, J. Thomsen, Joachim Schuz, Michael Kosteljanetz, Hans Skovgaard Poulsen, Christoffer JohansenAbstract:Despite limited evidence, Cellular Telephones have been claimed to cause cancer, especially in the brain. In this Danish study, the authors examined the possible association between use of Cellular Telephones and development of acoustic neuroma. Between 2000 and 2002, they ascertained 106 incident cases and matched these persons with 212 randomly sampled, population-based controls on age and sex. The data obtained included information on use of Cellular Telephones from personal interviews, data from medical records, and the results of radiologic examinations. The authors obtained information on socioeconomic factors from Statistics Denmark. The overall estimated relative risk of acoustic neuroma was 0.90 (95% confidence interval: 0.51, 1.57). Use of a cell phone for 10 years or more did not increase acoustic neuroma risk over that of short-term users. Furthermore, tumors did not occur more frequently on the side of the head on which the Telephone was typically used, and the size of the tumor did not correlate with the pattern of cell phone use. The results of this prospective, population-based, nationwide study, which included a large number of long-term users of Cellular Telephones, do not support an association between cell phone use and risk of acoustic neuroma.
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Cellular Telephones and cancer a nationwide cohort study in denmark
Journal of the National Cancer Institute, 2001Co-Authors: Christoffer Johansen, John D. Boice, Joseph K. Mclaughlin, Jørgen H. OlsenAbstract:Background: Use of Cellular Telephones is increasing exponentially and has become part of everyday life. Concerns about possible carcinogenic effects of radiofrequency signals have been raised, although they are based on limited scientific evidence. Methods: A retrospective cohort study of cancer incidence was conducted in Denmark of all users of Cellular Telephones during the period from 1982 through 1995. Subscriber lists from the two Danish operating companies identified 420 095 Cellular Telephone users. Cancer incidence was determined by linkage with the Danish Cancer Registry. All statistical tests are two-sided. Results: Overall, 3391 cancers were observed with 3825 expected, yielding a significantly decreased standardized incidence ratio (SIR) of 0.89 (95% confidence interval [CI] = 0.86 to 0.92). A substantial proportion of this decreased risk was attributed to deficits of lung cancer and other smokingrelated cancers. No excesses were observed for cancers of the brain or nervous system (SIR = 0.95; 95% CI = 0.81 to 1.12) or of the salivary gland (SIR = 0.72; 95% CI = 0.29 to 1.49) or for leukemia (SIR = 0.97; 95% CI = 0.78–1.21), cancers of a priori interest. Risk for these cancers also did not vary by duration of Cellular Telephone use, time since first subscription, age at first subscription, or type of Cellular Telephone (analogue or digital). Analysis of brain and nervous system tumors showed no statistically significant SIRs for any subtype or anatomic location. Conclusions: The results of this investigation, the first nationwide cancer incidence study of Cellular phone users, do not support the hypothesis of an association between use of these Telephones and tumors of the brain or salivary gland, leukemia, or other cancers.
Donald A Redelmeier - One of the best experts on this subject based on the ideXlab platform.
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interpretation and bias in case crossover studies
Journal of Clinical Epidemiology, 1997Co-Authors: Donald A Redelmeier, Robert TibshiraniAbstract:The case-crossover design is an innovative epidemiologic technique with distinct strengths and limitations. We review the fundamental logic of this self-matching non-randomized design and direct attention to 15 concerns related to the available data, unavailable data, analytic technique, quantitative statistics, and etiologic model. Implications for each concern are discussed in the context of a recent report on whether Cellular Telephone calls are associated with an increased risk of a motor vehicle collision. We suggest that an understanding of the case-crossover design may help investigators explore selected questions in behavioral medical research.
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association between Cellular Telephone calls and motor vehicle collisions
The New England Journal of Medicine, 1997Co-Authors: Donald A Redelmeier, Robert TibshiraniAbstract:Background Because of a belief that the use of Cellular Telephones while driving may cause collisions, several countries have restricted their use in motor vehicles, and others are considering such regulations. We used an epidemiologic method, the case–crossover design, to study whether using a Cellular Telephone while driving increases the risk of a motor vehicle collision. Methods We studied 699 drivers who had Cellular Telephones and who were involved in motor vehicle collisions resulting in substantial property damage but no personal injury. Each person's Cellular-Telephone calls on the day of the collision and during the previous week were analyzed through the use of detailed billing records. Results A total of 26,798 Cellular-Telephone calls were made during the 14-month study period. The risk of a collision when using a Cellular Telephone was four times higher than the risk when a Cellular Telephone was not being used (relative risk, 4.3; 95 percent confidence interval, 3.0 to 6.5). The relative ri...
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association between Cellular Telephone calls and motor vehicle collisions
The New England Journal of Medicine, 1997Co-Authors: Donald A Redelmeier, Robert TibshiraniAbstract:BACKGROUND: Because of a belief that the use of Cellular Telephones while driving may cause collisions, several countries have restricted their use in motor vehicles, and others are considering such regulations. We used an epidemiologic method, the case-crossover design, to study whether using a Cellular Telephone while driving increases the risk of a motor vehicle collision. METHODS: We studied 699 drivers who had Cellular Telephones and who were involved in motor vehicle collisions resulting in substantial property damage but no personal injury. Each person's Cellular-Telephone calls on the day of the collision and during the previous week were analyzed through the use of detailed billing records. RESULTS: A total of 26,798 Cellular-Telephone calls were made during the 14-month study period. The risk of a collision when using a Cellular Telephone was four times higher than the risk when a Cellular Telephone was not being used (relative risk, 4.3; 95 percent confidence interval, 3.0 to 6.5). The relative risk was similar for drivers who differed in personal characteristics such as age and driving experience; calls close to the time of the collision were particularly hazardous (relative risk, 4.8 for calls placed within 5 minutes of the accident, as compared with 1.3 for calls placed more than 15 minutes before the accident; P<0.001); and units that allowed the hands to be free (relative risk, 5.9) offered no safety advantage over hand-held units (relative risk, 3.9; P not significant). Thirty-nine percent of the drivers called emergency services after the collision, suggesting that having a Cellular Telephone may have had advantages in the aftermath of an event. CONCLUSIONS: The use of Cellular Telephones in motor vehicles is associated with a quadrupling of the risk of a collision during the brief time interval involving a call. Decisions about regulation of such Telephones, however, need to take into account the benefits of the technology and the role of individual responsibility.