ID Number		958
Study Type		In Vivo
Model		Studies of chick embryos exposed to RF (915 MHz, CW) and 60 Hz magnetic fields.
Details		Chick embryos were exposed to 915 MHz (CW)for 20, 30, or 60 minutes, either once or twice a day, for 4 days using a cell phone at 3.5 mWatts power output. RF exposure once daily (but not twice daily) for 30 or 60 minutes per day resulted in statistically significant decreased protection against hypoxia. ELF exposure also decreased protection against hypoxia, but only with exposure (either 30 or 60 minutes) twice daily for 4 days. The authors suggested this result was consistent with earlier observations that ELF exposure decreased hsp70 levels by 27% hsp70 following long term (4 day) 60 Hz ELF exposure at 8 uT. Further, superimposing ELF "noise" blocked the effect of both RF and ELF exposures. Earlier studies by the same group showed increases in hypoxia protection following short term ELF 60 Hz ELF or RF (915 MHz) exposures. The authors conclude that RF induced decreases in HSP70 levels and cytoprotection might enhance the probability of cancer and other diseases. AUTHORS' ABSTRACT: Di Carlo and Litovitz 1999 (IEEE #5571): Work in bioelectromagnetics has long been plagued by problems with replication. This includes experiments done on electromagnetic (EM) field-induced effects in chick embryos. Our laboratory investigated responses of embryos from two flocks of White Leghorn hens. Both flocks were studied simultaneously, and it was found that they responded differently to EM field exposures. Embryos were exposed to 60 Hz, 8 microT EM fields prior to placement in an anoxic chamber. Following re-oxygenation, survival in controls was 34.6%, exposed flock 1 survival was 62% (P < 0.0001) and exposed flock 2 survival was 43% (P < 0.0136). P values are from comparison of data between EM field exposed embryos (flocks 1 and 2) versus controls. In order to induce maximum protection in flock 2, (approximately 62% survival), embryos required a longer exposure time at higher magnetic field strengths. These results reinforce the concepts that genetics are important in determining whether or not chick embryos will respond to EM field stimulation. A broader look at the role of genetic factors emphasizes that these variations in response to external stimuli (e.g., drugs, radiation, and EM fields) are found in all areas of biological research (cell culture, chick, rat, and human studies). The present study suggests that genetics may be a prime cause of the difficulties encountered in replication studies in the field of bioelectromagnetics. We conclude that replication studies should not be undertaken unless care is taken to insure that exactly the same strains of cells or animals are used. Researchers should also first confirm that the responses of their model to non-EM field stimuli are similar to that obtained in the original study.
Findings		Effects
Status		Completed With Publication
Principal Investigator		Catholic University, Washington DC, USA
Funding Agency		Private/Instit.
Country		UNITED STATES
References		Shallom, JM et al. J Cell Biochem, (2002) 86:490-496 Di Carlo, A et al. J Cell Biochem, (2002) 84:447-454 Litovitz, TA et al. Bioelectromagnetics, (1994) 15:105-113 Di Carlo , AL et al. Bioelectrochem Bioenerg., (1999) 48:209-215 Di Carlo, AL et al. Bioelectrochemistry., (2001) 53:87-95 Di Carlo, AL et al. Bioelectromagnetics., (1998) 19:498-500 Di Carlo, AL et al. International journal of radiation biology., (1999) 75:1541-1549
Comments