1) CI Kowalczuk et al: Biological Effects of Exposure to Non-ionizing Electromagnetic Fields and Radiation. I. Static Electric and Magnetic Fields (NRPB-R238), National Radiation Protection Board, Chilton, (1991).
- "There are insufficient data on which to base restrictions on human exposure to static electric fields. For static magnetic fields, the data suggest that occupational exposures should not exceed about [2000 mT]... Prolonged exposure to static magnetic fields of up to [2000 mT] does not produce any detrimental effects of many developmental, behavioral and physiological parameters in animals... There is no evidence of mutagenesis or carcinogenesis... In view of the relative lack of information regarding the possible long-term effects, it is reasonable on present evidence to restrict the exposure of workers so that the average exposure over one day does not exceed 200 mT and to restrict exposure of members of the public to less than 200 mT."
2) MA Stuchly: Human exposure to static and time-varying magnetic fields, Health Phys. 51:215-225 (1986).
- Review of human exposures to static and ELF magnetic fields, and regulations covering exposure.
3) NIOSH Health Hazard Evaluation Report: Alumax of South Carolina, Centers for Disease Control and Prevention, NIOSH, (1994).
- In an aluminum reduction plant, static fields were as high as 70 mT with time-weighted averages of 15-16 mT.
4) R VonKaenel et al: The determination of the exposure to electromagnetic fields in aluminum electrolysis, In: "Light Metals 1994", U Mannweiler., ed., The Minerals, Metals and Materials Society, pp. 253-260 (1994).
- Static fields were 4-20 mT at various locations around the pots. Personnel monitoring showed average fields of 2-4 mT, with very large variations and peaks as high at 25 mT.
5) JL Marsh et al: Health effect of occupational exposure to steady magnetic fields, Amer. Indust. Hygiene Assoc. J. 43:387-394 (1982).
- Case-control study of electrolysis workers exposed to a static fields of up to 20 mT. No significant general health effects were found (cancer was not explicitly studied). Some effects on white cell counts were found, but they were not statistically significant.
6) L Barregard et al: Cancer among workers exposed to strong static magnetic fields (letter), Lancet October 19, 1985:892 (1985).
- Cohort study of Swedish workers in a chloralkali plant. Measured fields ranged from 4 to 29 mT. Mortality rates for total cancer were not elevated for workers exposed for greater than 1 year, or for workers exposed for more than 5 years.
7) TF Budinger et al: Biological effects of static magnetic fields, In: "Proceedings of the 3rd Annual Meeting of the Society for Magnetic Resonance in Medicine", Society for Magnetic Resonance in Medicine, Berkeley, pp. 113-114 (1984).
- Case-control study of worker who were exposed to static magnetic fields from accelerators. Exposures ranged from 0.5 mT for long periods of time to 300 mT for short periods. No significant increase in malignant or benign neoplasms was found.
8) S Milham: Mortality in aluminum reduction plant workers, J. Occup. Med. 21:475-480 (1979).
- Cohort study with an emphasis on air quality, the exposure to static fields was coincidental. Elevated mortality was found for lymphatic and hematopoietic cancer, and for fatal benign brain tumors. Leukemia and brain cancer mortality was not elevated.
9) HE Rockette and VC Arena: Mortality studies of aluminum reduction plant workers: Potroom and carbon department, J. Occup. Med. 25:549-557 (1983).
- Cohort study of aluminum reduction plant workers designed to investigate a hypothesized excess of lung cancer, the exposure to static fields was coincidental. No statistically significant excess cancer rates were found for any site, although non-significant excesses were observed for pancreatic cancer, kidney cancer, lymphatic and hematopoietic cancer.
10) JM Mur et al: Mortality of aluminium reduction plant workers in France, Int. J. Epidem. 18:257-264 (1987).
- Standardized mortality ratio study of workers in aluminum reduction plants, designed to look for excess lung cancer. The mortality rate for overall cancer was not significantly elevated, and no individual types of tumors were found to be in significant excess.
11) AB Hill: The environment and disease: Association or causation? Proc. Royal Soc. Med. 58:295-300 (1965).
- Formal enunciation of the principles used to determine causation for occupational and environmental exposures (the Hill criteria).
12) DS Beniashvili et al: Low-frequency electromagnetic radiation enhances the induction of rat mammary tumors by nitrosomethyl urea, Cancer Letters 61:75-79 (1991).
- Study of the effects of a 0.2 mT static fields (0.5 or 3 hrs/day for 2 years) on the induction of mouse mammary tumors by nitrosomethyl urea. Authors report no effects are reported for static fields alone, but promotion was reported for 3 hr exposures. Exposure, and particularly sham-exposure conditions are poorly described.
13) DD Mahlum et al: Dominant lethal studies in mice exposed to direct-current magnetic fields, In: "Biological effects of extremely low frequency electromagnetic fields", RD Phillips et al., eds., Battelle Pacific Northwest Laboratory, Richland, WA, pp. 474-484 (1979).
Male mice were exposed to a 1000 mT static field for 28 days. After exposure the animals were bred to unexposed females. No increase in fetal deaths or dominant lethal mutations was observed.
14) S Mittler: Failure of magnetism to influence production of X-ray induced sex-linked recessive lethals, Mutat. Res. 13:287-288 (1971).
- Fruit flies were exposed to a 1100 mT static field and/or 3300 R of X-rays. The magnetic field alone did not increase the number of mutations, and the field did not increase the incidence of x-ray induced mutations.
15) JR Diebolt: The influence of electrostatic and magnetic fields on mutation in Drosophila melanogaster spermatozoa, Mutat. Res. 57:169-174 (1978).
- No sex-linked recessive mutation in fruit flies exposed to static (0.3 kV/cm) electric and magnetic (927 mT) fields.
16) PG Kale and JW Baum: Genetic effects of strong magnetic fields in Drosophila melanogaster, I. Homogeneous fields ranging from 13,000 to 37,000 Gauss, Mutat. Res. 1:371-374 (1979).
- No induction of mutations in fruit flies exposed to 1300-3700 mT static fields.
18) P Cooke and PG Morris: The effects of NMR exposure on living organisms. II. A genetic study of human lymphocytes, Br. J. Radiol. 54:622-625 (1981).
- Lymphocytes were exposed to 500 and 1000 mT static fields or to MRI imaging procedures. No effects of chromosomal abnormalities or sister chromatid exchanges were observed.
19) CR Geard et al: Magnetic resonance and ionizing radiation: A comparative evaluation in vitro of oncogenic and genotoxic potential, Radiology 152:199-202 (1984).
- Mouse cells were exposed to static fields of up to 2700 mT for periods of up to 17 hours, together with the gradient field, and the RF fields that would be used in MRI. Ionizing radiation was used as a positive control. No effect on transformation and chromosome abnormality rates were found.
20) FJ Peteiro-Cartelle and J Cabezas-Cerrato: Absence of kinetic and cytogenetic effects on human lymphocytes exposed to static magnetic fields, J. Bioelec. 8:11-19 (1989).
- PHA-stimulated human lymphocytes were exposed for 72-96 hours in culture to a static field at 45 and 125 mT. No effects on chromosome aberrations or cell growth were observed.
21) VV Shevchenko et al: [On the problem of induction of chromosome aberrations in plants by a constant magnetic field], Genetika 14:1101-1103 (1978).
- Plant seeds were germinated in a static magnetic field at 900 mT and 1200 mT for 2 days, or dry seeds were exposed for 2 months to a 900 mT static magnetic field. No increase in chromosome aberrations was observed.
22) S Wolff et al: Magnetic resonance imaging: Absence of in vitro cytogenetic damage, Radiology 155:163-165 (1985).
- Human (stimulated and unstimulated) lymphocytes and CHO cells were exposed for 12.5 hrs to a MRI unit with a static field of 2400 mT plus 100-MHz RF. No increases in chromosome aberrations or sister chromatid exchanges were observed.
23) S Wolff et al: Tests for DNA and chromosomal damage induced by nuclear magnetic resonance imaging, Radiology 136:707-710 (1980).
- CHO cells were exposed for 14 hrs to a 350 mT static field together with a gradient field (up to 0.2 mT/cm), and the RF fields (15 MHz at 5 mW/cm-sq) that would be used in MRI. Experiments were also run with higher RF power. No chromosomal aberrations were observed.
24) E Yamazaki et al: Effect of Gd-DTPA and/or magnetic field and radiofrequency exposure on sister chromatid exchange in human peripheral lymphocytes, Acta Radiol. 34:607-611 (1993).
- PHA-stimulated lymphocytes were exposed to a 1500 mT static field plus RF at 64 MHz (SAR of 0.4 W/kg) and Gd-DTPA. The addition of the Gd-DTPA caused an increase in chromosome aberrations, but no effects on chromosome aberrations were observed for the fields alone.
25) ME Frazier et al: In vitro evaluations of static magnetic fields, In: "Biological effects of extremely low frequency electromagnetic fields", RD Phillips et al., eds., Technical Information Center, US Department of Energy, Springfield, pp. 417-435 (1979).
- Mammalian cells were exposed to 500 or 1000 mT static fields for 2, 4 or 24 hours, or to 100 or 300 mT fields for up to 67 days. No effects on cell growth rates, cell viability or cell transformation were observed.
26) RL Moore: Biological effects of magnetic fields: studies with microorganisms, Can. J. Microbiol. 25:1145-1151 (1979).
- Ames test with exposures at 0 to 0.3 Hz to fields of 15 and 30 mT. No increase in mutations were observed.
27) JL Schwartz and LE Crooks: NMR imaging produces no observable mutations or cytotoxicity in mammalian cells, Amer. J. Roent. 139:583-585 (1982).
- Mammalian cells were exposed for 24 hrs to a static field at 300 mT, together with a gradient field (up to 0.2 mT/cm), and the RF fields (15 MHz at 3 mW/sq.-cm) that would be used in MRI. No cytotoxicity or mutagenicity (6-TG system) were observed.
28) A Thomas and PG Morris: The effects of NMR exposure on living organisms. I. A microbial assay, Br. J. Radiol. 54:615-621 (1981).
- Bacteria were exposed to a 1000 mT static field and to the conditions used in an MRI (900 mT static field plus RF and gradient field). Not mutagenic or cytotoxic effects were observed.
29) J McCann et al: The genotoxic potential of electric and magnetic fields: an update. Mutat Res 411:45-86, 1998.
- A review of 27 studies of the genotoxicity of static fields concludes that there is no confirmed evidence that static magnetic or electric fields are genotoxic. There are, however, several high quality studies that indicated that static fields of 1000-3700 mT are not genotoxic.
30) PG Kale and JW Baum: Genetic effects of strong magnetic fields in Drosophila melanogaster, II. Lack of interaction between homogeneous fields and fission neutron-plus-gamma radiation, Environ. Mutagen. 2:179-186 (1980).
- No enhancement of radiation-induced mutations in fruit flies exposed to a 3700 mT static field.
31) S Rockwell: Influence of a 1400-gauss magnetic fields on the radiosensitivity and recovery of EMT6 cells in vitro, Int. J. Rad. Biol. 31:153-160 (1977).
- Mouse mammary tumor cells were exposed to a 140 mT field alone, during or after x-ray treatment. Fields alone has no effect on cell growth. Fields had no effect on radiation-induced cell killing or on the repair of radiation damage.
32) T Takatsujiet al: Effect of static magnetic fields on the induction of chromosome aberrations by 4.9 MeV protons and 23 MeV alpha particles, J. Rad. Res. 30:238-246 (1989).
- Human lymphocytes were irradiated with and without a 1000-1400 mT static magnetic field. The authors report a small increase in the incidence of radiation-induced dicentrics in cells exposed to the static fields.
33) T Norimura et al: Effects of strong magnetic fields on cell growth and radiation response of human T-lymphocytes in culture, Sangyo Ika Diagaku Zasshi 15:103-112 (1993).
- Human lymphocytes were exposed to static magnetic fields. An inhibition of cell growth was observed at 4000 - 6300 mT, but not at 2000 mT or below. Exposure to a 4000 mT field increased radiosensitivity and decreased repair of radiation-induced damage.
34) PG Kale and JW Baum: Genetic effects of strong magnetic fields in Drosophila melanogaster. III. Combined treatment with homogeneous fields and gaseous DBCP, Mutat. Res. 105:79-83 (1982).
- A 1300 mT static magnetic field had no effects on the mutagenic effects of a chemical.
35) M Mevissen et al: Effects of magnetic fields on mammary tumor development induced by 7,12-dimethylbenz(a)anthracene in rats, Bioelectromag. 14:131-143 (1993).
- Animals were exposed to a 15 mT static field in the DMBA-induced breast tumor system. Exposure was for 24 hrs/day for 91 days. No overall promotion effects was observed. An increase in tumor weights was reported.
36) A Bellossi: The effect of a static uniform magnetic field on mice a study of methylcholanthrene carcinogenesis, Rad. Environ. Biophys. 23:107-109 (1984).
- Mice previously treated with methylcholanthrene (an initiator) were exposed to static magnetic fields from the day of methylcholanthrene injection until death, with fields of 300-800 mT, for 5-60 minutes per day and 1-5 days per week. No significant effect on survival or body weight was detected.
37) A Bellossi: The effect of a static non-uniform magnetic field on mice a study of Lewis tumour graft, Rad. Environ. Biophys. 25:231-234 (1986).
- Mice inoculated with tumor cells were exposed to a static field for 5 days/week, beginning the day of transplant and continuing until death. Exposure was for 0.5-2 hrs/day at fields of 170-900 mT. No effects on life span, spleen weight, or metastatic potential were found.
38) A Bellossi and L Toujas: The effect of a static uniform magnetic field on mice: A study of a Lewis tumor graft, Rad. Environ. Biophys. 20:153-157 (1982).
- Mice with tumor implants were exposed to static field of 13-915 mT. Exposure continued 5 days/week for 0.5-8 hours per day. No effect on animals survival was found in any group. The failure-to-take rate (the tumor is immunogenic) was also unchanged. There also appears to have been no effect on the rate of lung metastasis, but the manuscript is a bit unclear.
39) S Chandra and S Stefani: Effect of constant and alternating magnetic fields on tumor cells in vivo and in vitro, In: "Biological Effects of Extremely Low Frequency Electromagnetic Fields, Proceedings of the 18th Hanford Life Symposium ", RD Phillips et al., eds., Technical Information Center, U. S. DoE, Springfield, pp. 436-446 (1979).
- Exposure was to a 60-Hz field at 100-1000 mT or to a 11,500 mT static field. Exposure was for 0.5 to 3 hours/day, 1-3 days. Two human tumor cell lines exposed in vitro, and no effect on cell growth was observed. Mouse mammary tumor cells were exposed in culture, then implanted; no effect on tumor growth was observed. The mouse mammary tumor cells were also implanted and exposed in vivo; again, no effect on tumor growth was observed.
40) JH Battocletti et al: Exposure of rhesus monkeys to 20,000 G steady magnetic field: Effect on blood parameters, Med. Phys. 8:115-118 (1981).
- Monkeys were exposed to a uniform 2000 mT static field or to a gradient static field (700-2000 mT at 34 mT/cm) for 63-67 hours. Changes in white cells counts were found in both exposed animals; subsequent sham-exposures caused similar changes. No significant differences were observed between exposed and sham-exposed animals.
41) M Osbakken et al: A gross morphologic, histologic, hematologic, and blood chemistry study of adult and neonatal mice chronically exposed to high magnetic fields, Magnet. Reson. Med. 3:502-517 (1986).
- Mice were raised for varying periods of time in a 1890 mT static magnetic field. No differences were found in gross and microscopic morphology, blood counts or blood chemistry.
42) TS Tenforde and M Shifrine: Assessment of the immune responsiveness of mice exposed to a 1.5-Tesla stationary magnetic field, Bioelectromag. 5:443-446 (1984).
- Mice were exposed for 6 days to a 1500 mT static field. No effects on immune response or on mitogen-stimulated lymphocyte proliferation were observed.
43) BD Jankovic et al: Potentiation of immune responsiveness in aging by static magnetic fields applied to the brain. Role of the pineal gland, Ann. NY Acad. Sci. 719:410-418 (1994).
- Small magnets (60 mT) were implanted into the brains of rats; controls were sham-implanted with iron beads. The authors report an enhancement of animals immune response.
44) RL Davis and S Milham: Altered immune status in aluminum reduction plant workers, Amer. J. Indust. Med. 18:79-85 (1990).
- Authors report that a previous study had found excess lymphoma in employees of an aluminum reduction plant. Volunteers in similar jobs has elevated levels of certain classes of immune cells. The authors state that the cause and significance of the altered immunological parameters are unknown.
45) A Lerchl et al: Marked rapid alterations in nocturnal pineal seratonin metabolism in mice and rats exposed to weak intermittent magnetic fields, Biochem. Biophys. Res. Commun. 169:102-108 (1990).
- Mice were exposed to fields that were designed to reverse the earth's static field (0.4 mT). The coils were activated 6 times per hour for 5 minutes, so this is a pulsed field experiment. The exposure is reported to affect seratonin metabolism (but not very much) but not melatonin levels.
46) K Yaga et al: Pineal sensitivity to pulsed static magnetic fields changes during the photoperiod, Brain Research Bulletin 30:153-156 (1993).
- Melatonin production in rats was studied after exposure to a pulsed static magnetic field (1 min pulses for 45 minutes). The static field appears to have resulted in reversal of the Earth field. Slight decreases in melatonin production were reported, but only for exposures at certain times of day.
47) J Olcese et al: Evidence for the involvement of the visual system in mediating magnetic field effects on pineal melatonin synthesis in the rat, Brain Res. 333:382-384 (1985).
- Normal and blinded rats exposed to 0.05 and 0.1 mT static fields that produced a rotation of the horizontal component of the Earth field. The field is reported to cause a decrease in melatonin in intact, but not in blinded animals. Whether this suggests that the retina is the site of action of the magnetic field, or that there are visual clues is unclear.
48) RJ Reiter and BA Richardson: Magnetic field effects on pineal indoleamine metabolism and possible biological consequences, FASEB J. 6:2283-2287 (1992).
- Review of the hypothesis linking EMF effects with effects on melatonin production. The review notes that pulsed fields are the more effective than static or sinusoidal fields.
49) RJ Reiter: Electromagnetic fields and melatonin production, Biomed. Pharmacother. 47:439-444 (1993).
- "the current data are not sufficient compelling to conclude that any cancer which may appear to occur in individuals exposed to magnetic fields has any association with a change in melatonin synthesis"
50) MH Repacholi et al: Guidelines on limits of exposure to static magnetic fields, Health Phys. 66:100-106 (1994).
- The ICNIRP occupational guideline is that continuous occupational exposure should be limited to a time-weighted value that does not exceed 200 mT. Continuous exposure of the general public should not exceed 40 mT. These values may not be suitable for people with cardiac pacemakers, ferromagnetic implants and implanted electronic devices; for these people, exposures should be kept below 0.5 mT. See also 81.
51) E Kanal et al: Safety considerations in MR imaging, Radiology 176:593-606 (1990).
- Eight area of potential concern in MRI safety are reviewed. "It may be safely concluded that although no deleterious biological effects from the static magnetic fields used in MRI have been definitively associated with this modality, all the facts are by no means in yet, and further research is continuing..."
52) International Non-Ionizing Radiation Committee: Protection of the patient undergoing a magnetic resonance examination, Health Phys. 61:923-928 (1991).
- For the static magnetic-field the IRPA guideline is to monitor cardiovascular status above 2000 mT, and not exceed 10,000 mT. "The scientific literature does not indicate adverse effects from exposure of the whole-body to 2 T (2000 mT) and of the extremities to 5 T (5000 mT)".
53) JF Schenck: Health and physiological effects of human exposure to whole-body four-Tesla magnetic fields during MRI, Ann. NY Acad. Sci. 649:285-301 (1992).
- "Although no health abnormalities were noted [in preclinical trials of 4000 mT MRI units], there were several instances of mild sensory effects... A strong argument can be made that the potential hazards of these effects up to field strengths of 4 T [4000 mT] are well below thresholds set the stability of human tissue..."
54) G Miller: Exposure guidelines for magnetic fields, Amer. Indust. Hygiene Assoc. J. 48:957-968 (1987).
- The Lawrence Livermore static magnetic field exposure guidelines, with a detailed review of the bioeffects data and of the basis for the standard. Guidelines: at 1 mT, exclude pacemakers and warn those with prosthetics; at 50 mT, training and medical surveillance are required, and those with sickle cell anemia are excluded; 2000 mT is the peak exposure allowed.
55) FS Prato et al: Blood-brain barrier permeability in rats is altered by exposure to magnetic fields associated with magnetic resonance imaging at 1.5 T, Micro. Res. Tech. 27:528-534 (1994).
- Exposure of rats to MRI conditions or to a 1500 mT static field increased blood-brain barrier permeability. "The effect of MRI on blood-brain barrier permeability is poorly understood... additional experiments are needed to understand the importance of static field, RF field and gradient field".
56) K Schulten: Magnetic field effects in chemistry and biology, Adv. Solid State Phys. 22:61-83 (1982).
- "Chemical and biological photoprocesses which involve bimolecular reactions between non-zero spin intermediates... can be influenced by magnetic fields". The examples discussed all involve field strengths of at least 1 mT, and generally over 10 mT.
57) JC Scaiano et al: Model for the rationalization of magnetic field effects in vivo. Application of the radical-pair mechanism to biological systems, Photochem. Photobiol. 59:585-589 (1994).
- A model is proposed for magnetic field effects in biological systems. The model involved effects on the chemistry of radical pairs. The result of the magnetic field is to increase the life-time and hence the concentration of free radicals.
58) National Radiation Protection Board: Restrictions on human exposure to static and time varying electromagnetic fields and radiation, Document of the NRPB 4 (5):1-69 (1993).
- The basic restrictions for static magnetic fields are 5000 mT maximum to limbs, 2000 mT maximum to whole body and 200 mT averaged over 24 hours. For static electric fields the maximum is 25 kV/m.
59) Documentation of Threshold Limit Values, American Conference of Government Industrial Hygienists, Cincinnati, OH, (1994).
- The static field standard is that "routine occupational exposures should not exceed 60 mT (600 G) whole body or 600 mT (6000 G) to the extremities on a daily, time-weighted basis... A flux density of 2 T [2000 mT] is recommended as a ceiling value.
60) Environmental Health Criteria 69, Magnetic Fields, World Health Organization, Geneva, Switzerland, (1987).
- "from the available data it can be concluded that short-term exposure to static magnetic fields of less than 2000 mT does not present a health hazard."
61) A Ronneberg and A Andersen: Mortality and cancer morbidity in workers from an aluminium smelter with prebaked carbon anodes -- part II: cancer morbidity. Occup Environ Med 52:250-254, 1995.
- A study of cancer in men working in an aluminum smelter. Exposure of interest included: coal tar volatiles, asbestos, fluorides, sulfur dioxide, heat stress and magnetic fields. An excess of total cancer was observed for workers with less than three years of employment, but not with workers with longer employment. No significant excess of leukemia, lymphoma or brain cancer was observed. No association of magnetic field exposure and CNS or hematopoietic cancer was found.
62) JE Moulder and KR Foster: Biological effects of power-frequency fields as they relate to carcinogenesis. Proc Soc Exp Biol Med 209:309-324, 1995.
- A review of the biophysics, biology and epidemiology of power-frequency fields and cancer as they relate to cancer. Co-authored by the maintainer of this FAQ sheet.
63) G Taubes: Epidemiology faces its limits. Science 269:164-169, 1995.
- "The search for subtle links between diet, lifestyle, or environmental factors and disease is an unending source of fear -- but often yields little certainty.
64) JJ Schlesselman: "Proof" of cause and effect in epidemiologic studies: Criteria for judgment. Prev Med 16:195-210, 1987.
- A review of the criteria used to asses causation in epidemiologic studies, with some interesting historical context and discussion.
65) T Koana et al: Estimation of genetic effects of a static magnetic field by a somatic cell test using mutagen-sensitive mutants of Drosophila melanogaster. Bioelectrochem Bioenerg 36:95-100, 1995.
- Larvae of Drosophila (fruit flies) were exposed to a 600 mT static field for 24 hours. Both normal larvae and mutants lacking a DNA repair gene were exposed. Fewer of the mutants survived, which the authors interpret as implying increased DNA damage that the mutants could not repair.
66) JA Malko et al: Search for influence of 1.5 Tesla magnetic field on growth of yeast cells. Bioelectromag 15:495-501, 1994.
- Yeast were exposed to a 1.5 T (1500 mT) static field for 7 cell generations, with no effect of cell growth.
67) IV Balyasnikova et al: Effect of a static magnetic field on the growth rate and in vitro angiogenesis of endothelial cells. Bulletin of Experimental Biology and Medicine 117:110-113, 1994.
- A 140 mT static magnetic field is reported to stimulate growth of bovine endothelial cells, but to have no effects on human endothelial cells. The effects are small, and not seen under all conditions.
68) RL Levine et al: Magnetic field effects on spatial discrimination and melatonin levels in mice. Physiology and Behavior 58:535-537, 1995.
- Mice were exposed for 100 minutes to a 2000 mT field. Effects on spatial discrimination learning were observed, but effects on melatonin were not found.
69) E Farber: Cell proliferation as a major risk factor for cancer: A concept of doubtful validity. Cancer Res 55:3759-3762, 1995.
- "It is now being proposed that the presence of cell proliferation by itself or the stimulation of cell proliferation in a quiescent tissue... should in and of themselves major concerns for cancer development... However, whether cell proliferation, per se, is a risk factor for the long process of cancer development has not been demonstrated..."
70) GR Krueger: Abnormal variation of the immune system as related to cancer. Cancer Growth Prog. 4:139-161, 1989.
- In the early 1970's there was speculation that the immune system had a major role in preventing the development of cancer; this theory was known as the "immune surveillance hypothesis". If this hypothesis were true, then damage to the immune system could effectively cause cancer. Subsequent studies have shown that this hypothesis is not generally valid. Suppression of the immune system in animals and humans is associated with increased rates of only certain types of cancer, particularly lymphomas. Immune suppression has not been associated with an excess incidence of leukemia, except for viral-induced leukemia in animals; and has not been associated with brain or breast cancer in either animals or humans.
71) B Brocklehurst and KA McLauchlan: Free radical mechanism for the effects of environmental electromagnetic fields on biological systems. Int J Rad Biol 69:3-24, 1996.
- The radical pair reactions provide a mechanism whereby magnetic fields of environmental levels might effect biological systems. The authors note that "the radical pair system sees any field of less than about 10 MHz as static". Effects are theoretically possible down to fields of geomagnetic strength, and the authors demonstrate effects at static fields as low as 0.1 mT. The effects seen at 0.1 mT are an approximately 1% increase in free radical concentrations. The authors say that this "1% is very small, and the body possesses sophisticated defense mechanisms to cope with these radicals under normal conditions".
72) F McDonald: Effect of static magnetic fields on osteoblasts and fibroblasts in vitro. Bioelectromag 14:187-196, 1993.
- Rat fetal tissue explants and cells in culture were exposed to a 610 mT static field for 1-10 days. The authors report stimulation of tritiated thymidine incorporation in fibroblast cell culture, but inhibition in fibroblast explants. No effects were seen in osteoblasts under the same conditions.
73) W Pavlicek et al: The effects of nuclear magnetic resonance on patients with cardiac pacemakers. Radiology 147:149-153, 1983.
- Pacemakers were exposed to MRI conditions. The threshold for static magnetic field effects was 1.7 mT. The RF field and the gradient fields may also create problems.
74) B Kula and M Drozdz: A study of magnetic field effects on fibroblast cultures: The evaluation of the effects of static and extremely low frequency (ELF) magnetic fields on vital functions of fibroblasts. Bioelectrochem Bioenerg 39:21-26, 1996.
- Cultured fibroblasts were exposed to a 490 mT static field or a 20 mT 50 Hz field for 2-64 min per day for 4 days. 50-Hz field exposure was reported to decrease cell growth and DNA synthesis. The static field had no effects on cell growth and DNA synthesis.
75) R Kavet: EMF and current cancer concepts. Bioelectromag 17:339-357, 1996.
- A summary of current concepts of carcinogenesis written for bioelectromagnetics researchers. "Current thinking holds that carcinogenesis is a multi-step process that requires at least two genotoxic events in its critical path but that is facilitated by nongenotoxic proliferative effects on target cells..." The authors argue that: "If magnetic fields influence carcinogenesis, then most likely it would be through a proliferative stimulus [which could] operate either through receptor-mediated or nonreceptor-mediated mechanisms".
76) RR Raylman et al: Exposure to strong static magnetic field slows the growth of human cancer cells in vitro. Bioelectromag 17:358-363, 1996.
- Three malignant human cell lines were exposed to a 7000 mT static field for 64 hours. Exposure lead to decreased cell growth, but no cell cycle effects and no DNA stand breaks were found.
77) N Mohtat et al: Magnetic field effects on the behavior of radicals in protein and DNA environments. Photochem Photobiol 67:111-118, 1998.
- Exploration of how static fields influence the rates of free radical reactions, and how they might have effects on DNA. The paper notes "the fields employed] here [20-140 mT are much larger than those relating to typical environmental or occupational exposure"
78) H Okonogi et al: The effects of a 4.7 tesla static magnetic field on the frequency of micronucleated cells induced by mitomycin C. Tohoku J Exp Med 180:209-215, 1996.
- Mammalian cells were exposed to a 4700 mT static field for 6 hours. Exposure resulted in a decrease in micronucleus formation induced by exposure to mitomycin-C. Exposure to the field alone had no effect on micronucleus formation.
79) BI Rapley et al: Influence of extremely low frequency magnetic fields on chromosomes and the mitotic cycle in Vicia faba L, the broad bean. Bioelectromag 19:152-161, 1998.
- Exposure of bean sprouts (Vicia faba) to a 5 mT static field for 3 days did not cause chromosome breaks.
80) P Chadwick et al: Magnetic fields on British trains. Ann Occup Hyg 5:331-335, 1998.
- Electric trains produced both static and AC fields. At seat height within the passenger compartment, static fields can be up to 0.2 milliT. Actual exposure levels are very dependent on equipment design and location within the train.
81) International Commission on Non-Ionizing Radiation Protection: Guidelines for limiting exposure to time-varying electric, magnetic, and electromagnetic fields (up to 300 GHz). Health Phys 74:494-522, 1998.
- The ICNIRP occupational guideline is that continuous occupational exposure below 1 Hz should be limited to a time-weighted value that does not exceed 200 mT. Continuous exposure of the general public should not exceed 40 mT below 1 Hz. Also see 50.
82) JM Mur et al: Demographic evaluation of the fertility of aluminium industry workers: influence of exposure to heat and static magnetic fields. Human Repro 13:2016-2019, 1998.
- Aluminum industry workers who work in the "potroom" are exposed to static fields of 4-30 mT (they are also exposed to heat sufficient to raise core body temperature). The fertility rate of potroom workers was higher than that of controls
83) VR Narra et al: Effects of a 1.5-Tesla static magnetic field on spermatogenesis and embryogenesis in mice. Invest Radiol 31:586-590, 1996.
- Male and pregnant female mice were exposed to a 1500 mT static field for 30 minutes. The authors report a 15% reduction in testicular sperm in males, and 40% decrease in the development of the embryos in vitro. Sham exposures were not done and the study was not blinded.
84) L Tablado et al: Is sperm motility maturation affected by static magnetic fields? Environ Health Perspect 104:1212-1216, 1996.
- Mice were exposed to a 700 mT static field for 1 or 24 hrs/day and for 10 and 35 days. No effects on sperm production, sperm motility or sperm maturation were observed.
85) PN Baker et al: A three-year follow-up of children imaged in utero with echo-planar magnetic resonance imaging. Amer J Obstet Gynecol 170:32-33, 1994.
- Three-year followup of 20 children examined in utero (2nd and 3rd trimester) by MRI. No increases in disease or disability were found. One of the 20 pregnancies ended in prenatal death. Birth weight and median gestational age were normal.
86) M Mevissen et al: Effects of static and time-varying (50-Hz) magnetic fields and reproduction and fetal development in rats. Teratology 50:229-237, 1994.
- Mated rats were exposed to a 30 mT static field from days 1 to 20 of pregnancy. No adverse effects were seen in dams. The mean number of viable fetuses was reduced (from 11 to 9 per litter) in the animals exposed to static fields. The incidence of minor skeletal abnormalities was reduced in the animals exposed to static fields. When dams were exposed to 30 mT for the entire pregnancy, postnatal growth was enhanced, but behavior was not affected.
87) JA Evans et al: Infertility and pregnancy outcome among magnetic resonance imaging workers. J Occup Med 35:1191-1195, 1993.
- A questionnaire study of MRI workers showed no significant effect on fertility, birth weight, or miscarriage rate.
88a) DA Tyndall: MRI effects on craniofacial size and crown-rump length in C57BL/6J mice in 1.5T fields. Oral Surg Oral Med Oral Pathol 76:655-660, 1993.
88b) DA Tyndall et al: Effects of magnetic resonance imaging on eye development in the C57BL/6J mouse. Teratology 43:263-275, 1991.
- Pregnant mice were exposed to a 1500 mT static field for 36 min as part of MRI. An increase in minor skeletal and eye abnormalities was seen in the exposure animals. Heating due to the RF exposure used as part of the MRI cannot be ruled out.
89) J Murakami et al: Fetal development of mice following intrauterine exposure to a static magnetic field of 6.3 T. Magn Reson Imaging 10:433-437, 1992.
- Pregnant mice were exposed to a static magnetic field of 6300 mT for 1 hr/day from days 7-14 of gestation. No significant differences between exposed and control groups were observed regarding litter size, fetal weight, intrauterine mortality rate, or external and skeletal anomalies.
90) G Konermann et al: Untersuchungen über den einfluss staticher magnetfelder uaf die pränatale entwicklung der maus [Studies of the influence of a static magnetic field on prenatal development in mice]. Radiologe 26:490-497, 1986.
- Pregnant mice were exposed to a 1000 mT static field for 1 hour on days 7, 10 and 13 post-conception. No effects were observed on fetal mortality, malformations rates, or fetal weights.
91) D McRobbie et al: Pulsed magnetic field exposure during pregnancy and implications for NMR foetal imaging: a study with mice. Magn Reson Imaging 3:231-234, 1985.
- Pregnant mice were exposed at various times during gestation to a 1500 mT static field as part of MRI exams . No adverse effect was observed on litter numbers and growth rates of the exposed litters.
92) MR Sikov et al: Development of mice after intrauterine exposure to direct-current magnetic fields, In: "Biological effects of extremely low frequency electromagnetic fields", RD Phillips et al., eds., Battelle Pacific Northwest Laboratory, Richland, WA, pp. 462-473 (1979).
- Pregnant mice were exposed either to a 1000 mT static field on 0.5-7, 6-15, 10-18, or 0.5-17 days of gestation or at 6-18 days old. No physical or neurological developmental abnormalities were found.
93) M Nakagawa: Effects of magnetic fields on fertility, general reproductive performance and growth of mice. Nippon Eiseigaku Zasshi 34:488-495, 1979.
- Pregnant mice and subsequent litters were exposed continuously to static fields of 30 or 80 mT. Fertility was decreased by 30% at 80 mT, but there was no effect at 30 mT. At both 30 and 80 mT, there was an insignificant increase in neonatal deaths and a possibly significant increase in male prenatal mortality.
94) M Ikehata, T Koana et al: Mutagenicity and co-mutagenicity of static magnetic fields detected by bacterial mutation assay. Mutat Res 427:147-156, 1999.
- Bacteria exposed to 5000 mT static fields showed no increase in mutations. Exposure to the 5000 mT static field did increase the mutagenicity of some chemical mutagens.
95) L Tablado, C Soler et al: Development of mouse testis and epididymis following intrauterine exposure to a static magnetic field. Bioelectromag 21:19-24,2000.
- Pregnant mice were exposed to 500-700 milliT static fields from 7 days of gestation through birth. No effects were seen on body weight of the mothers, litter size, body weight of pups, malformation rate, miscarriage rate or testicular development in male pups.
96) T Sommer, C Vahlhaus et al: MR imaging and cardiac pacemakers: In vitro evaluation and in vivo studies in 51 patients at 0.5 T. Radiology 215:869-879, 2000.
- Exposure of cardiac pacemakers to MRI imaging, including a 500 milliT static field, showed that MR imaging could be safely performed in patients with cardiac pacemakers.
97) J Wiskirchen, EF Grönewäller et al: Human fetal lung fibroblasts: In vitro study of repetitive magnetic field exposure to 0.2, 1.0, and 1.5 T. Radiology 215:858-862, 2000.
- Exposure of human cells to static fields of 200, 1000 or 1500 milliT for 1 hr/day on 5 consecutive days had no effect on cell growth.
98) RW Eveson, CR Timmel et al: The effects of weak magnetic fields on radical recombination reactions in micelles. Int J Radiat Biol 76:1509-1522, 2000.
- In an experimental system, exposure to magnetic fields pulsed at 2 Hz could produce effects on free radical reactions at field strengths as low as 1-2 milliT.
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