ID Number		20
Study Type		In Vivo
Model		900 MHz (GSM) exposure to mice and analysis of lymphomas (PIM-1 transgenic bioassay)
Details		E&mgr (Pim1 heterozygous transgenic) mice (n = 800, 120 per group) mice and an equal number of wild type controls were exposed in restraining tubes in a ferris wheel exposure system in the far field to 898.4 MHz (GSM) RF at 0.25, 0.5, 1.0, or 4.0 W/kg (whole body average) for 1 hour/day, 5 days/wk, for 104 weeks. This study was a replication of the study performed by Repacholi et al., (Radiation Research (1997) 147(5):631-640) with additional control animals, additional dose levels, and significant modifications to the exposure system to improove the characterization of RF dose. The study reported no effects of exposure on lymphoma incidence. An independent pathological review was performed by the NIEHS in the US as well as a laboratory in Europe.
Findings		No Effects
Status		Completed With Publication
Principal Investigator		Inst. of Med. and Vet. Sci., Australia - tim.kuchel@imvs.sa.gov.au
Funding Agency		NHMRC, Australia
Country		AUSTRALIA
References		Utteridge, TD et al. Radiat. Res., (2002) 158:357-364 Kundi, M et al. Radiat. Res., (2003) 159:274-278
Comments		While the study was performed in a more controlled manner than the initial study, the paper was written in a somewhat confusing manner. Notably, survival curves and weight gain curves showed mice gaining and maintaining weight after death. Comments on the study from Kundi, Goldstein et al; Lerchl et al; and Utteridge et al were published ~4 months after the study was printed. Comments on the Comments: 1. Kundi's suggestion that the restraining tubes were "disasterous", comparing this with "immobilization stress", was uninformed. Many inhalation studies are done with appropriate restraint to maintain body orientation without completely immobilizing which is used as an experimental model for inducing stress. The referece to Stagg et al (WHO #62) showed more the opposite of what Kundi would use this paper to verify, that there was no fos or ODC mRNA change, and only slight ACTH and corticosterone induction due to the restraint. Any claim that the Utteridge restraint and well characterized exposure was less informative and inferior to the 1000 fold variations in dosimetry experienced in the initial study is incorrect. Both Kundi (and Lin, IEEE Ant. Prop., 2003, 44:165) directly compare the 75% incidence rate at the end of the 24 month Utteridge study with the 22% mortality rate after 18 months in the Repacholi study, which cannot be done, these values cannot be directly compared. To speculate that in a lifetime study with similar cumulative exposure, that some "window" effect of time may influence the results (2 x 30 minute daily exposures instead of 1 x 60 minute daily, or 7 days / wk instead of 5 days / week) is purely speculation and argues against any obvious logical mechanism that might be envisioned for a direct effect of low level RF exposure. Other factors are controlled for within the sham exposed population, and the Kundi comments are irrelevant. 2. The Goldstein article also refers to incidence rate in the Repacholi study also, and there was no incidence rate determined, only mortality rate. 3. Lerchl had very good comments, I thought - he pointed out legitimate weaknesses in the paper that should have been addressed, but none of these took away from the findings, but were comments on how the data should have been better presented in the publication. 4. The Utteridge et al response is a good rebuttal listing these inconsistencies and expounding on others.