198
Electromagnetic Fields in Biological Systems
effects of ELF EMF on human health has been completed. There are many review publications on the potential biological and human health effects of ELF EMF (NAS 1996;
NIEHS 1998; IARC 2002; ICNIRP 2003). Based on the evaluation of biological and
human health effect research, the World Health Organization (WHO) carried out the
human health assessment of ELF EMF and published a monograph of the Environmental
Health Criteria (EHC) for ELF EMF (up to 100 kHz) in 2007 (WHO 2007a).
In addition to the review of the successful development in evaluation of biological
studies and human health effects, the progress of ELF EMF and intermediate frequency
(IF) magnetic field studies in Japan will be reviewed from both experimental and engineering perspectives. Otaka (2001) has briefly reviewed Japanese research efforts on ELF
EMF (partly including the study of radio frequency EMF). Historically, from the end of
the 1970s to early 1980s, research on biological and engineering issues had begun in several universities and research organizations across Japan. Some research involved studies on the biological effects of ELF electric field on animals and the distribution of the
electric fields and induced currents from a high-voltage transmission line in humans.
Additional research revealed interaction mechanisms between humans or animals
and ELF EMF (Barnes 1988, 1992, 2007; Foster 2003). In Japan, research on ELF EMF
was carried out mainly by two research groups: one from Hokkaido University and the
other from the University of Tokushima. In addition to actual measurement of induced
currents and electric fields, they used models of the human body represented by simple structures such as cylinders to estimate induced currents and surface electric fields
(Chiba et al. 1984; Shimizu, Endo, and Matsumoto 1988a,b). The results of these studies
explained the electric field distribution inside and outside the human body exposed to
a high-voltage transmission line. For biological studies using mice, rat, and cats, carefully constructed exposure facilities were successfully developed (Kobayashi et al. 1983;
Negishi et al. 2008; Shigemitsu et al. 1981, 1993; Yamazaki et al. 2000a). These facilities helped the research group from Hokkaido University make great contributions to
animal-related research (Kato et al. 1986, 1989). For instance, one successful research
outcome revealed the impact of various polarized magnetic fields on secretion of melatonin in rats (Kato and Shigemitsu 1997). Dosimetric studies in animals exposed to
ELF electric fields were conducted jointly by the United States and Japan at the Central
Research Institute of Electric Power Industry (CRIEPI) and the University of Tokushima
(Takuma et al. 1990).
In recent years, devices such as the household induction heating cooker, radio frequency identification tag readers, and electronic article surveillance tags for theft prevention are all being increasingly used in households. These devices use the magnetic
fields of the ELF and IF regions. There have been concerns on the association between
the exposure to IF magnetic fields and human health. So far, no basic research data on
the biological effects of IF magnetic fields are available (Shigemitsu et al. 2007). Further
studies on the biological effects and health risk assessments of IF magnetic field, ranging from tens of kilohertz to about 100 kHz, are needed. Based on Japanese traditional
research dedicated to the study of ELF EMF and in order to ensure protection from
exposure to IF magnetic field, pioneering research on the biological effects of IF magnetic field started in Japan in the early 2000. The CRIEPI developed in vivo and in vitro
exposure facilities for the investigation of toxicological and reproductive effects in
Electromagnetic Fields in Biological Systems
effects of ELF EMF on human health has been completed. There are many review publications on the potential biological and human health effects of ELF EMF (NAS 1996;
NIEHS 1998; IARC 2002; ICNIRP 2003). Based on the evaluation of biological and
human health effect research, the World Health Organization (WHO) carried out the
human health assessment of ELF EMF and published a monograph of the Environmental
Health Criteria (EHC) for ELF EMF (up to 100 kHz) in 2007 (WHO 2007a).
In addition to the review of the successful development in evaluation of biological
studies and human health effects, the progress of ELF EMF and intermediate frequency
(IF) magnetic field studies in Japan will be reviewed from both experimental and engineering perspectives. Otaka (2001) has briefly reviewed Japanese research efforts on ELF
EMF (partly including the study of radio frequency EMF). Historically, from the end of
the 1970s to early 1980s, research on biological and engineering issues had begun in several universities and research organizations across Japan. Some research involved studies on the biological effects of ELF electric field on animals and the distribution of the
electric fields and induced currents from a high-voltage transmission line in humans.
Additional research revealed interaction mechanisms between humans or animals
and ELF EMF (Barnes 1988, 1992, 2007; Foster 2003). In Japan, research on ELF EMF
was carried out mainly by two research groups: one from Hokkaido University and the
other from the University of Tokushima. In addition to actual measurement of induced
currents and electric fields, they used models of the human body represented by simple structures such as cylinders to estimate induced currents and surface electric fields
(Chiba et al. 1984; Shimizu, Endo, and Matsumoto 1988a,b). The results of these studies
explained the electric field distribution inside and outside the human body exposed to
a high-voltage transmission line. For biological studies using mice, rat, and cats, carefully constructed exposure facilities were successfully developed (Kobayashi et al. 1983;
Negishi et al. 2008; Shigemitsu et al. 1981, 1993; Yamazaki et al. 2000a). These facilities helped the research group from Hokkaido University make great contributions to
animal-related research (Kato et al. 1986, 1989). For instance, one successful research
outcome revealed the impact of various polarized magnetic fields on secretion of melatonin in rats (Kato and Shigemitsu 1997). Dosimetric studies in animals exposed to
ELF electric fields were conducted jointly by the United States and Japan at the Central
Research Institute of Electric Power Industry (CRIEPI) and the University of Tokushima
(Takuma et al. 1990).
In recent years, devices such as the household induction heating cooker, radio frequency identification tag readers, and electronic article surveillance tags for theft prevention are all being increasingly used in households. These devices use the magnetic
fields of the ELF and IF regions. There have been concerns on the association between
the exposure to IF magnetic fields and human health. So far, no basic research data on
the biological effects of IF magnetic fields are available (Shigemitsu et al. 2007). Further
studies on the biological effects and health risk assessments of IF magnetic field, ranging from tens of kilohertz to about 100 kHz, are needed. Based on Japanese traditional
research dedicated to the study of ELF EMF and in order to ensure protection from
exposure to IF magnetic field, pioneering research on the biological effects of IF magnetic field started in Japan in the early 2000. The CRIEPI developed in vivo and in vitro
exposure facilities for the investigation of toxicological and reproductive effects in