Health physics
-
The purpose of this study is to evaluate the potential for electromagnetic interference (EMI) and to assess the immunity level of implantable pacemakers (PM) when exposed to the radiofrequency (RF) field generated by Wi-Fi devices. Ten PM from five manufacturers, representative of what today is implanted in patients, have been tested in vitro and exposed to the signal generated by a Wi-Fi transmitter. An exposure setup that reproduces the actual IEEE 802.11b/g protocol has been designed and used during the tests. ⋯ The results of this study mitigate concerns about using Wi-Fi devices close to PM: none of the PM tested exhibit any degradation of their performance, even when exposed to RF field levels five times higher than those allowed by current international regulation (20 W EIRP). In conclusion, Wi-Fi devices do not pose risks of EMI to implantable PM. The immunity level of modern PM is much higher than the transmitting power of RF devices operating at 2.4 GHz.
-
In areas contaminated by radioactive materials, well designed dose assessment is necessary in order to protect people from radiation exposure and manage the exposure situation appropriately. Probabilistic dose assessment is a useful method for providing a more complete characterization of information on dose distributions in the population and requires statistically characterized data on pathway-relevant contributors. The objective of this paper is to determine statistical features of contributors to external exposures, as well as to identify causes of variabilities of individual doses to the populations living in areas contaminated by the Fukushima Daiichi Nuclear Power Plant accident. ⋯ Results showed that the ambient dose equivalent rate also distributed with lognormal form, and it had variabilities attributable to the spatial distribution of deposited radionuclides. The distribution form of time spent outdoors depends on the characteristics of occupation, and the distributions for indoor workers and outdoor workers were lognormal and normal, respectively. Results of a multiple-regression analysis suggested that such variabilities of contributors give rise to significant differences in individual doses among the populations.
-
The Radiation Effects Research Foundation (RERF) studies various cohorts of Japanese atomic bomb survivors, the largest being the Life Span Study (LSS), which includes 93,741 persons who were in Hiroshima or Nagasaki at the times of the bombings; there are also cohorts of persons who were exposed in utero and survivors' children. This presentation attempts to summarize the total impact of the radiation from the bombs on the survivors from both an individual perspective (both age-specific and integrated lifetime risk, along with a measure of life expectancy that describes how the risk affects the individual given age at exposure) and a group perspective (estimated numbers of excess occurrences in the cohort), including both early and late effects. As survivors' doses ranged well into the acutely lethal range at closer distances, some of them experienced acute signs and symptoms of radiation exposure in addition to being at risk of late effects. ⋯ Interaction of radiation with other risk factors has been demonstrated in relation to both cancer and noncancer diseases. Current research interests include whether radiation increases risk of diabetes or conditions of the eye apart from cataract, and there continues to be keen interest as to whether there are heritable effects in survivors' children, despite negative findings to date. Introduction of Impact on the Japanese Atomic- Bomb Survivors (Video 1:52, http://links.lww.com/HP/A29).
-
Historical Article
Increased occupational radiation doses: nuclear fuel cycle.
The increased occupational doses resulting from the Chernobyl nuclear reactor accident that occurred in Ukraine in April 1986, the reactor accident of Fukushima that took place in Japan in March 2011, and the early operations of the Mayak Production Association in Russia in the 1940s and 1950s are presented and discussed. For comparison purposes, the occupational doses due to the other two major reactor accidents (Windscale in the United Kingdom in 1957 and Three Mile Island in the United States in 1979) and to the main plutonium-producing facility in the United States (Hanford Works) are also covered but in less detail. Both for the Chernobyl nuclear reactor accident and the routine operations at Mayak, the considerable efforts made to reconstruct individual doses from external irradiation to a large number of workers revealed that the recorded doses had been overestimated by a factor of about two. Introduction of Increased Occupational Exposures: Nuclear Industry Workers. (Video 1:32, http://links.lww.com/HP/A21).
-
This review summarizes the current state of research on possible health effects of Wi-Fi (a commercial name for IEEE 802.11-compliant wireless networking). In response to public concerns about health effects of Wi-Fi and wireless networks and calls by government agencies for research on possible health and safety issues with the technology, a considerable amount of technology-specific research has been completed. A series of high quality engineering studies have provided a good, but not complete, understanding of the levels of radiofrequency (RF) exposure to individuals from Wi-Fi. ⋯ S. and international exposure limits for RF energy. While several studies report biological effects due to Wi-Fi-type exposures, technical limitations prevent drawing conclusions from them about possible health risks of the technology. The review concludes with suggestions for future research on the topic.