ID Number		427
Study Type		In Vivo
Model		900 MHz (GSM), 2450 MHz (CW) exposure to mice and analysis of cancer (DMH-initiated colon and DMBA-initiated mammary tumor bioassays)
Details		In initial studies, Balb/C mice (4-5 wks old) were exposed dorsally to 2450 MHz (CW) RF at an SAR of 10-12 W/kg for 3 h/day, 6 days/wk for 5 months using physiotherapy machines (models WB-150 and WB-732) following treatment with dimethylhydrazine (DMH - 0.15% administered sc once a wk for 14 wks followed by injection sc with 0.2% for the next 8 wk) to induce colon tumors. As a positive control for tumor promotion, DMH treated mice were treated with TPA once per wk for 10 wks starting 2 wks after the first DMH treatment. Mice were sacrificed after 25 weeks and analyzed for colon tumors. No effects of microwave exposure were observed, although TPA treatment was observed to promote colon tumors. In subsequent studies, Sprague Dawley rats (n = 100 per group) +/- mammary tumor initiation with DMBA were exposed to 900 MHz (GSM) RF for 4h/d, 5d/week, for 26 weeks and analyzed for mammary tumors. The rats were divided into three exposure groups (SARs of 0.44, 1.33, 4.0) plus a sham exposure and a cage control group. The authors reported no statistically significant effect of RF exposure on tumor incidence, tumor multiplicity, or tumor size between sham-exposed and RF-exposed rats. The authors reported a statistically significant decrease in tumor latency with both exposed and sham groups as compared to the cage control group, but they attributed this result to the impact of food deprivation during exposure. There was also a significantly higher incidence of benign mammary tumors and total mammary tumors in the control group than in other groups. The authors conclude that the study did not provide evidence that 900 MHz GSM exposure promotes mammary tumor incidence, onset, or growth rate.
Findings		No Effects
Status		Completed With Publication
Principal Investigator		Zhijiang Medical College, China - hch@mail.hz.zj.cn
Funding Agency		EU, CDC / NIEHS, China, MMF, GSM Association
Country		CHINA
References		Yu, D et al. Radiation Research, (2006) 165:174-180 Wu, RY et al. Bioelectromagnetics, (1994) 15:531-538
Comments		During exposure, rats had no access to food or water. Not all results consistent with Hruby et al 2007