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The History of Bioelectromagnetism

and Yamazaki, 2012). For biological studies using mice, rats, and cats, carefully constructed exposure

facilities were successfully developed (Kobayashi et al., 1983; Negishi et al., 2008; Shigemitsu et al., 1981).

Tese facilities helped the research group and made great contributions to animal-related research (Kato

et al., 1986, 1989, 1993; Kato and Shigemitsu, 1997). So far, no basic research data on the biological efects

of IF-magnetic feld is available (Shigemitsu et al., 2007). Further studies on the biological efects and

health risk assessment of IF-magnetic feld ranging from tens of kHz to about 100 kHz are needed. Based

on Japanese traditional research dedicated to the study of ELF-EMF, pioneering research on the biologi­

cal efects of IF-magnetic feld started in Japan in the early 2000. Te CRIEPI developed in vivo and in

vitro exposure facilities for the investigation of toxicological and reproductive efects in experimental

animals (Nakasono et al., 2008; Shigemitsu et al., 2009). In cellular experiments, microorganisms and

cells were used to study the mutagenic efect of IF-magnetic feld, using the newly built in vitro exposure

facilities (Fujita et al., 2007; Miyakoshi et al., 2007).

During the last four decades, research on the interaction between extremely low-frequency (50/60 Hz)

ELF-EMF and biological systems has increased signifcantly (WHO, 1984, 1987). In addition to bio­

logical research, major research on the possible adverse efects of ELF-EMF on human health has been

completed. During this time, there have been many review publications on the potential biological and

human health efects of ELF-EMF (NRC, 1997a; NIEHS, 1998; IARC, 2002; ICNIRP, 2003). In 1996, the

WHO established the International EMF Project which focused frst on research to determine the link

between ELF-magnetic feld exposure to human and childhood leukemia. In 2001, the IARC assessed

the carcinogenicity of ELF-magnetic feld exposure, which resulted in a health risk assessment of ELF

magnetic feld exposure. IARC categorized ELF-magnetic feld to be as possible carcinogenic to humans

in the IARC carcinogenic category of 2B. Based on the evaluation of biological and human health efect

research, the WHO carried out the human health assessment of ELF-EMF and published a monograph

of the EHC for ELF-EMF (up to 100 kHz) in 2007 which states:

Although a causal relationship between magnetic feld exposure and childhood leukemia has not

been established, the possible public health impact has been calculated assuming causality in order

to provide a potentially useful input into policy.

WHO (2007, p. 12)

Tis means that the possibility of causality was taken into consideration in the health risk assessment.

Even afer the IARC categorized ELF-magnetic feld as Group 2B, the discussion about a causal rela­

tionship between ELF-magnetic feld and childhood leukemia still has controversy. On the other hand,

the ELF-electric feld has no association with carcinogenicity: not classifable as to its carcinogenicity to

humans (Group 3) (IARC, 2002).

2.6.3 Radiofrequency Fields

Afer the experimental discovery of electromagnetic waves by Hertz, the medical and military applica­

tions using RF felds have been developed since roughly around the 1930s. In the late 1940s, reports on

microwave exposure were related to the microwave diathermy in medical research. In the early 1950s,

the military and industrial concern focused on the hazards related to microwave exposure. In particu­

lar, with the introduction of medical use for diathermy, the debate over non-thermal and thermal efects

of microwaves began and the debate continued still even afer World War II.

During and afer World War II, microwave technology was studied not only for military use but also

for civilian use. Communication technologies (e.g., wireless telephony) have advanced rapidly in recent

years; hence, microwave energy now is ubiquitous in the atmosphere. In the late 1940s, it was reported

that clicking sounds could be heard near a radar station. Te RF hearing efect was systematically stud­

ied about 15 years later (Frey, 1961), concomitant with other studies of microwave efects on other organs

and tissues, such as the eyes and the nervous system. Two shaped development of early research on the