Unknown authors · 1998
Researchers exposed HL60 cells (a type of human blood cell) to either X-rays or 60 Hz magnetic fields and examined changes in gene expression. While X-ray exposure altered the activity of 18 genes related to cell growth and stress responses, the 60 Hz magnetic fields produced no detectable changes in gene expression. This suggests that power-line frequency magnetic fields may not trigger the same cellular stress responses as ionizing radiation.
Nakamura et al. · 1998
Researchers exposed pregnant rats to microwave radiation at 2.45 GHz for 90 minutes and found it suppressed natural killer cells, which fight infections and cancer. This immune suppression occurred through the body's opioid system, showing microwave exposure can weaken immunity during pregnancy when protection is most critical.
Kavaliers M, Choleris E, Prato FS, Ossenkopp K · 1998
Researchers exposed land snails to 60-Hz magnetic fields from power lines and found the fields disrupted the animals' natural pain relief systems by altering brain chemistry. This shows that common household electrical frequencies can interfere with basic biological processes controlling pain in living organisms.
Malyapa RS et al. · 1998
Researchers exposed rats to microwave radiation at 2450 MHz (the same frequency used in microwave ovens) for 2 hours to test whether it causes DNA breaks in brain cells. They found no DNA damage in either the brain's cortex or hippocampus regions, contradicting an earlier study that reported such damage. This suggests that short-term exposure to this type of microwave radiation at moderate levels may not harm brain cell DNA.
Unknown authors · 1997
Researchers exposed rats to 60 Hz magnetic fields (the same frequency used in North American power grids) for 2 hours and found dose-dependent DNA damage in brain cells. Higher magnetic field strengths caused both single-strand and double-strand DNA breaks, with effects measured 4 hours after exposure. This DNA damage could potentially contribute to cancer development and neurodegenerative diseases.
Unknown authors · 1997
This 1997 study examined how 60 Hz magnetic fields at 2 mT strength affected gene expression in three different human cell lines. The researchers found no significant effects on gene activity, suggesting that power line frequency magnetic fields at this strength don't alter cellular gene expression patterns. This adds to evidence that certain EMF exposures may not cause immediate biological changes at the genetic level.
Unknown authors · 1997
This 1997 physics-based analysis examined whether 50/60 Hz electromagnetic fields (power line frequencies) at residential levels could cause biological effects in humans. The researchers concluded that such effects are implausible based on current understanding of physics and biology, as the forces generated are far weaker than normal biological processes.
Lai H, Singh NP · 1997
Researchers exposed rats to 60-Hz magnetic fields (the same frequency as household electricity) and found that this exposure caused DNA breaks in brain cells. However, when the rats were given melatonin or another antioxidant compound before exposure, these protective substances completely blocked the DNA damage. This suggests that magnetic fields may damage DNA through free radical formation, and that antioxidants might offer protection.
Malyapa RS et al. · 1997
Researchers exposed lab-grown cells to microwave radiation at 2450 MHz (the same frequency used in microwave ovens and older WiFi) for up to 24 hours to see if it would damage DNA. Using a highly sensitive test called the comet assay, they found no DNA damage at either exposure level tested. This contradicted earlier studies that suggested microwave radiation could break DNA strands in brain cells.
Vijayalaxmi et al. · 1997
Researchers exposed cancer-prone mice to 2450 MHz radiofrequency radiation (the same frequency used in microwave ovens and some WiFi) for 20 hours daily over 18 months to test whether it causes DNA damage. They measured micronuclei - tiny fragments that indicate genetic damage - in blood and bone marrow cells. The study found no significant difference in DNA damage between exposed and unexposed mice, suggesting this level of RF exposure did not cause detectable genetic harm.
Unknown authors · 1997
Researchers in Taiwan studied 3,427 cancer cases to examine whether living near power lines increases cancer risk. They found that people exposed to magnetic fields above 0.2 microtesla had a 40% higher risk of leukemia, and those living within 50 meters of transmission lines faced double the leukemia risk. No increased risk was found for brain tumors or breast cancer.
Litovitz et al. · 1997
Researchers exposed cells to microwave radiation from cell phones and found it increased activity of an enzyme called ornithine decarboxylase, which is linked to cell growth and potentially cancer. However, when they added low-frequency electromagnetic 'noise' during the exposure, it completely blocked these cellular effects. This suggests that certain types of electromagnetic interference might actually protect cells from microwave damage.
Unknown authors · 1997
Finnish researchers studied 12,063 people living near high-voltage power lines and found that while general depression levels weren't affected, those living within 100 meters of transmission lines had a 4.7-fold increased risk of severe depression. The study tracked participants for 20 years and used standardized depression assessments.
Gos, P, Eicher, B, Kohli, J, Heyer, WD · 1997
Researchers exposed yeast cells (Saccharomyces cerevisiae) to extremely high frequency electromagnetic fields around 41.7 GHz at very low power levels to see if the radiation affected how quickly the cells divided. After careful testing with proper controls, they found no significant differences in cell division rates between exposed and unexposed yeast. This contradicts some earlier studies that claimed to find biological effects from similar EMF exposures.
Jensh RP · 1997
Pregnant rats exposed to microwave radiation at cell phone and microwave oven frequencies showed concerning effects in offspring. The highest frequency (6000 MHz) caused delayed development, reduced birth weight, and altered brain function, suggesting certain microwave frequencies may affect developing brains.
Unknown authors · 1997
FDA researchers exposed human T-lymphocyte immune cells to 60 Hz magnetic fields at 0.15 mT (1,500 times stronger than typical household levels) to test whether power line frequencies affect cellular calcium signaling. The study found no changes in intracellular calcium responses under both optimal and stressed cell conditions. However, researchers noted this doesn't rule out effects on other calcium-dependent processes deeper in the cellular pathway.
Unknown authors · 1997
Researchers studied 540 adults living near high-voltage power lines, measuring magnetic field exposure in their homes and testing their psychological health. They found that higher magnetic field exposure was linked to worse performance on coding tests and increased psychiatric symptoms, even after accounting for other factors.
Unknown authors · 1997
Researchers exposed rat tracheal cells to gamma radiation alone or combined with 50 Hz electromagnetic fields at 100 microtesla. While EMF alone caused no DNA damage, cells exposed to both gamma radiation and EMF showed significantly more genetic damage than radiation alone. This suggests power frequency fields may amplify cancer-causing effects of other radiation sources.
Vijayalaxmi, Mohan, N, Meltz, ML, Wittler, MA, · 1997
Researchers exposed human blood cells to microwave radiation at 2450 MHz (the same frequency used in microwave ovens and WiFi) for 90 minutes to see if it would damage DNA or affect cell growth. They found no genetic damage, chromosome breaks, or changes in how fast the cells multiplied compared to unexposed cells. This suggests that short-term exposure to this type of radiation at these power levels may not immediately harm human blood cells.
Unknown authors · 1997
Researchers exposed human blood cells to 2450 MHz radiofrequency radiation (microwave oven frequency) for 90 minutes and found no genetic damage or changes in cell division. The study tested both continuous and intermittent exposure patterns at power levels similar to some industrial microwave applications.
Nakamura H, Seto T, Nagase H, Yoshida M, Dan S, Ogino K. · 1997
Japanese researchers exposed pregnant and non-pregnant rats to microwave radiation at 2450 MHz (the same frequency used by microwave ovens and WiFi) for 90 minutes at 10 mW/cm². They found that pregnant rats showed significant immune system suppression, with reduced natural killer cell activity in the spleen, while non-pregnant rats showed no immune changes. The study reveals that pregnancy makes organisms more vulnerable to microwave radiation effects.
Klug S, Hetscher M, Giles S, Kohlsmann S, Kramer K, · 1997
German researchers exposed developing rat embryos to radio frequency electromagnetic fields at various power levels for up to 36 hours to test whether EMF exposure during critical development stages causes birth defects or growth problems. The study found no significant effects on embryo development, growth, or cellular structure across all tested exposure levels, including levels far exceeding typical telecommunication device emissions. This suggests that RF fields at these intensities may not pose developmental risks during embryonic growth.
Lai H, Carino MA, Singh NP · 1997
Researchers exposed rats to microwave radiation at 2.45 GHz for 2 hours and found significant DNA double strand breaks in brain cells. When they gave rats naltrexone (a drug that blocks the body's natural opioids), it partially prevented the DNA damage. This suggests that microwave radiation triggers the body's opioid system, which then contributes to genetic damage in brain tissue.
Lai, H, Carino, MA, Singh, NP, · 1997
Researchers exposed rats to 2.45 GHz microwave radiation (the same frequency used in WiFi and microwave ovens) for 2 hours and found it caused DNA double strand breaks in brain cells. When they gave the rats naltrexone, a drug that blocks the body's natural opioids, it partially prevented this DNA damage. This suggests the body's own opioid system plays a role in how microwave radiation damages DNA in brain cells.
Unknown authors · 1997
This 1997 meta-analysis examined multiple studies on leukemia risk for people living near high-voltage power lines (49 kV and above). Researchers found a 30% increased leukemia risk for magnetic field exposures at 2 milligauss or higher, with risk increasing at higher exposure levels. The analysis included both adults and children living within 50 meters of transmission lines.