Lack of promotion of mammary, lung and skin tumorigenesis by 20 kHz triangular magnetic fields.
In order to evaluate possible tumorigenic effects of a 20 kHz intermediate frequency triangular magnetic field (IF), a frequency emitted from TV and PC monitors at 6.25 microT rms, which is the regulated exposure limit of magnetic field for the public in Korea, mammary tumors were produced in female Sprague-Dawley rats by oral intubation of dimethylbenz(a)anthracene (DMBA), lung tumors in ICR mice by scapular region injection of benzo(a)pyrene (BP), and skin tumors in female ICR mice by topical application of DMBA and tetradecanoylphorbol ester (TPA). IF was applied 8 h/day for 14 weeks beginning the day after DMBA treatment for mammary tumor experiment, for 6 weeks after weaning for lung tumor, and for 20 weeks beginning 1 week after DMBA application for skin tumor experiment. For skin tumors, TPA was applied once a week for 19 weeks. Results showed no significant differences in tumor incidence, mean tumor number and volume, and histological patterns between IF magnetic-field exposed and sham control rats in the above three tumor models. Therefore, we conclude that within the limitation or number of animals and the experimental conditions, 20 kHz IF triangular magnetic field exposure of 6.25 microT does not appear to be a strong co-tumorigenic agent in the chosen murine mammary, lung and skin models.
Lee
Hae-June
HJ
Laboratory of Radiation Effect, Korea Institute of Radiological and Medical Sciences, Seoul, Korea.
Choi
Soo-Yong
SY
Jang
Ja-June
JJ
Gimm
Youn-Myoung
YM
Pack
Jeong-Ki
JK
Choi
Hyung-Do
HD
Kim
Nam
N
Lee
Yun-Sil
YS
D000818:Animals; D004307:Dose-Response Relationship, Radiation; D004574:Electromagnetic Fields; D005260:Female; D008175:Lung Neoplasms / Q000209:etiology* / Q000473:pathology*; D008297:Male; D015674:Mammary Neoplasms, Animal / Q000209:etiology* / Q000473:pathology*; D051379:Mice; D008813:Mice, Inbred ICR; D009381:Neoplasms, Radiation-Induced / Q000209:etiology / Q000473:pathology*; D011829:Radiation Dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D012878:Skin Neoplasms / Q000209:etiology* / Q000473:pathology*