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Exposure to hexavalent chromium and 1800 MHz electromagnetic radiation can synergistically induce intracellular DNA damage in mouse embryonic fibroblasts
This PubMed-listed in vitro study tested whether 1800 MHz RF-EMF exposure can modify chemically induced DNA damage in mouse embryonic fibroblasts under standardized, non-thermal conditions. The authors report RF-EMF alone did not produce detectable DNA damage and did not significantly increase damage from hydrogen peroxide, 4-nitroquinoline-1-oxide, or cadmium. However, co-exposure with hexavalent chromium (Cr(VI)) was reported to synergistically increase DNA damage in the comet assay, which the authors interpret as possible selective exacerbation of Cr(VI)-induced genotoxicity requiring further investigation.
The International Collaborative Animal Study of Mobile Phone Radiofrequency Radiation Carcinogenicity and Genotoxicity: The Japanese Study
This PubMed-listed animal study reports results from the Japanese arm of an international Japan–Korea collaboration evaluating whether long-term mobile-phone-like RF-EMF exposure causes cancer or genetic damage in rats. Male Sprague Dawley rats were exposed to 900 MHz CDMA-modulated RF-EMF at a whole-body SAR of 4 W/kg for nearly 18.5 hours/day over two years, alongside OECD/GLP genotoxicity and carcinogenicity testing. The authors report no statistically significant increases in neoplastic or non-neoplastic lesions in major organs and no evidence of DNA or chromosomal damage, concluding the findings do not support reproducible carcinogenic or genotoxic effects under these conditions.
The International Collaborative Animal Study of Mobile Phone Radiofrequency Radiation Carcinogenicity and Genotoxicity: The Japanese Study
This international collaborative animal study (Japanese arm) evaluated carcinogenicity and genotoxicity in male Sprague Dawley rats exposed long-term to 900 MHz CDMA-modulated RF-EMFs at 4 W/kg whole-body SAR. The abstract reports no statistically significant increases in neoplastic or non-neoplastic lesions in major organs and no evidence of genotoxicity on comet or micronucleus testing. The authors conclude the findings provide strong evidence of no reproducible carcinogenic or genotoxic effects under the studied conditions.
Exposure to hexavalent chromium and 1800 MHz electromagnetic radiation can synergistically induce intracellular DNA damage in mouse embryonic fibroblasts
This in vitro study tested whether 1800 MHz RF-EMF modifies chemically induced DNA damage in mouse embryonic fibroblasts under non-thermal exposure conditions. RF-EMF alone did not produce detectable DNA damage and did not significantly enhance damage from hydrogen peroxide, 4NQO, or cadmium. In contrast, co-exposure with hexavalent chromium (Cr(VI)) was reported to synergistically increase DNA damage, suggesting a selective co-genotoxic interaction under specific chemical conditions.
DNA Damage Analysis in Blood Tissue & Physiopathological Evaluation of the Effect of Quercetin on Kidney Tissue in 2600 MHz EMF Exposure
This rat study assessed 30-day 2600 MHz EMF exposure effects on kidney tissue and DNA damage in blood lymphocytes, with an EMF+quercetin group included. Kidney histopathology and immunohistochemistry were reported as similar across groups, and oxidative stress markers did not significantly change. The EMF-only group showed significant DNA damage in lymphocytes by Comet assay.
Development and Testing of a Novel Whole-body Exposure System for Investigative Studies of Radiofrequency Radiation in Rodents (NIEHS)
This NIEHS report describes the development and testing of a flexible whole-body radiofrequency radiation exposure system for rats and mice using updated signals relevant to wireless technologies. In 5-day studies with CDMA- and GSM-modulated signals, no visible behavioral responses were observed and comet assays reported no DNA damage in multiple tissues. The report notes technical challenges, particularly difficulty obtaining reliable body temperature measurements during exposure, and positions the system as a prototype for future mechanistic toxicology studies.
Oxidative stress and testicular damage induced by chronic exposure to 35.5 GHz millimeter wave radiation in male Wistar rats
This randomized controlled animal study examined chronic 35.5 GHz millimeter wave exposure in male Wistar rats (2 hours/day for 60 days) compared with control and sham groups. The exposed group showed reduced sperm count and viability along with testicular histopathological changes. Oxidative stress markers shifted toward increased lipid peroxidation and reduced antioxidant defenses, and comet assay results indicated increased DNA damage.
Genotoxic and histopathological effects of 6 GHz radiofrequency electromagnetic radiation on rat liver tissue
This animal experiment exposed adult male rats to 6 GHz RF-EMR (0.065 W/kg) for 4 hours/day over 42 days and compared them with sham controls. The exposed group showed higher comet assay genotoxicity metrics, though not statistically significant, and more prominent liver histopathological changes (e.g., portal inflammation and congestion). The authors conclude that 6 GHz exposure can cause histopathological and DNA-level changes in rat liver tissue under the studied conditions.
Investigation of the Effects of 2.45 GHz Near-Field EMF on Yeast
This in vitro study exposed yeast suspensions to 2.45 GHz near-field microwave radiation at 2 cm and 4 cm for 20 or 60 minutes. It reports oxidative-stress-related changes (reduced antioxidant activity with increased membrane permeability) after 20 minutes at 2 cm, an effect not reproduced by conventional heating. The study also reports a trend toward increased DNA damage under both exposure conditions and mild membrane permeability changes after 60 minutes at 4 cm.
Effects of 700MHz radiofrequency radiation (5G lower band) on the reproductive parameters of female Wistar rats
This animal study examined short- and long-term 700 MHz (lower-band 5G) radiofrequency exposure in female Wistar rats, comparing control, sham, and exposed groups. It reports no DNA damage and no change in estrous cycle length, but increased ovarian oxidative stress markers in exposed animals. Long-term exposure was associated with ovarian histopathological alterations, while estradiol and progesterone stayed within normal ranges and testosterone increased slightly but significantly.
Toxicology and carcinogenesis studies in Sprague Dawley (Hsd:Sprague Dawley SD) rats exposed to whole-body radio frequency radiation at a frequency (900 MHz) and modulations (GSM and CDMA) used by cell phones
This National Toxicology Program technical report describes 900 MHz whole-body RFR exposures (GSM and CDMA) in male and female Sprague Dawley rats from in utero through up to 2 years. The report concludes clear evidence of carcinogenic activity in males for both modulations based on malignant schwannoma of the heart, with malignant glioma of the brain also reported as related to exposure. In females, the report concludes equivocal evidence of carcinogenic activity for both modulations based on selected tumor outcomes, and genetic toxicology findings were mixed with some comet assay increases/equivocal results but negative micronucleus assays.
Electromagnetic fields act via activation of voltage-gated calcium channels to produce beneficial or adverse effects
This narrative review argues that non-thermal biological effects of extremely low and microwave frequency EMFs may be mediated by activation of voltage-gated calcium channels (VGCCs). It cites 23 studies in which VGCC blockers reportedly block or reduce diverse EMF effects and proposes downstream Ca2+/calmodulin-dependent nitric oxide signaling. The review discusses both potential therapeutic effects (e.g., bone growth stimulation) and potential adverse effects via oxidative stress pathways, including a reviewed example of DNA single-strand breaks.
Electromagnetic fields and DNA damage
This review discusses the comet assay and summarizes research on non-ionizing EMF exposure and DNA/chromosomal damage. It describes both positive and negative findings across studies, noting no consistent overall pattern for radiofrequency radiation (RFR). The authors nonetheless conclude that under certain exposure conditions RFR appears genotoxic and may affect DNA damage and repair, with evidence discussed as most applicable to exposures typical of cell phone use.