Table 2.
Characteristics of individual vertebrate studies
| Author, year | Exposed animal (number of animals) | Exposure | Endpoints | Outcome | Remarks |
|---|---|---|---|---|---|
| Altmann [62] (article in German) |
guinea pig (n = 5 per group, crossover design) | static EF of 0.42 kV/m and control only under Faraday conditions | organ parameters: oxygen consumption |
metabolism was increased upon static EF exposure compared to a shielded environment in a Faraday cage | also studied AC EF; not clear if peer-reviewed |
| Altmann [49] (article in German) |
white mouse, budgerigar and zebra finch, guinea pig (n = ?) | static EF of 1 kV/m (mouse, budgie, zebra finch (exposure duration regarding activity assessment was 1 h)), 0.42 kV/m (guinea pig); control only under Faraday conditions | perception/behavior: activity (mouse, budgie, zebra finch), organ parameters: free amino acids in liver or muscle tissue (guinea pig, mouse) |
increased activity accompanied by higher oxygen consumption in guinea pig and higher level of free amino acids in all examined animals compared to a shielded environment in a Faraday cage | not clear if peer-reviewed |
| Angell et al. [44] | cattle (n = 200 in total; 2 herds of 50 animals under the HVDC line and 2 herds of 50 animals as controls) | static EF of 5.6 kV/m (mean value) and static MF (mean value of 4.1 nA/m2) and air ions (mean value of 13 k ions/cm3) from a 500 kV HVDC line continuously for 30 months | reproduction/development: productivity and general health status of cows and calves |
no significant effect | experimental field study; same animals as in Ganskopp et al. [45] |
| Arzruny et al. [74] | rats (n = 20 per group, 2 groups) | static EF of 200 kV/m for 1 h | hematology/immunology: enzyme activity of type A phospholipases, lysophospholipase in erythrocyte and mitochondrial membranes |
increase of enzyme activities in erythrocytes | |
| Atalay [59] | 40 male guinea pigs (10 vertical, 10 horizontal, 20 control) | static EF of 1.9 kV/m (horizontal and vertical) for 9 h/day for 3 days | organ parameters: collagen synthesis (hydroxyproline levels in lungs) |
increased hydroxyproline levels; vertical EF more effective than horizontal | |
| Atalay and Güler [63] | 40 male guinea pigs (10 vertical, 10 horizontal, 20 control) | static EF of 0.58 kV/m (horizontal and vertical) for 9 h/day for 3 days | organ parameters: collagen synthesis (hydroxyproline level in liver) |
decrease in hydroxyproline level; vertical EF more effective than horizontal | |
| Bailey and Charry [39] | male Sprague–Dawley rats (n = 5–20 per examined endpoint) | negative and positive static EF (3 kV/m, 12 kV/m) partially with air ions (5 × 103/cm3, 5 × 105/cm3) for 2, 18, or 66 h | perception/behavior: locomotor activity, rearing behavior, food and water consumption |
no significant effect | main focus was on air ions |
| Bailey and Charry [38] | male Sprague–Dawley rats (n = 6–16 per experiment) | negative and positive static EF of 3 kV/m without or with air ions (5*105/cm3) of the respective polarity; exposure duration 2, 18 or 66 h | brain/nervous system: serotonin level in the rat’s brain |
no significant effect | main focus was on air ions |
| Charry and Bailey [40] | male Sprague–Dawley rats (n = 5–15 per experiment) | negative and positive static EF of 3 kV/m without or with air ions (2*105/cm3) of the respective polarity; exposure duration 2, 18 or 66 h | brain/nervous system: norepinephrine and dopamine levels in the rat’s brain |
no significant effect | main focus was on air ions |
| Cieslar et al. [70] | 128 male Wistar albino rats (4 groups, 32 animals, respectively: 3 different EF strengths and a control group; 8 animals per time point: after 14, 28, 56 d of exposure or 28 d after a 56 d exposure) | static EF of 16, 25, or 35 kV/m for 8 h/day for 14, 28, or 56 days | organ parameters and hematology/immunology: oxidative stress (enzyme activity of catalase, superoxide dismutase, and level of gluthation peroxide, lipid peroxidation) in blood and liver |
transient changes in prooxidant-antioxidant balance | |
| Creim et al. [47] | male Long Evans rats; 380 rats in total, in 9 different experiments (n = 40, except for one experiment with n = 20) | negative and positive static EF (−55 to 80 kV/m) with air ions (1.4*106) or -/+ 55 kV/m with different air ion concentrations (2*103 to 2.5*105) for 1 h | perception/behavior: spatial avoidance behavior |
rats significantly avoided the exposed area (≥55 kV/m) regardless of air ions | |
| Creim et al. [46] | male Long Evans rats; 56 rats in total, divided into 4 groups (n = 14 per group) | negative and positive static EF of 75 kV/m with air ions (2*105) for 4 h/day for 5 days | perception/behavior: taste aversion learning |
no significant effect | |
| Fam [50] | male and female ICR-SW mice (for exposure: 2 groups, male and female n = 21, respectively and for control n = 24/24 male/female; additionally progenies of these 4 groups were exposed and examined) | static EF of 340 kV/m for 18–22 h/day, parents approx. 5000 h (approx. 30 weeks) in total and their progenies 2000 h in total | perception/behavior: water consumption hematology/immunology: blood parameters reproduction/development: growth; fertility; number and weight of pups organ parameters: histomorphology of different organs |
partially less water consumption; some changes in blood parameters (e.g., lower level of ß-globulins in males and higher in females, lower level of hemoglobin and reduced number of lymphocytes in females); weight of pups higher in first and fourth week after birth; no effect on number of pups; no effect on organ histomorphology |
|
| Ganskopp et al. [45] | see Angell et al. 1990 [44] | static EF of −3.3–24.7 kV/m under the positive conductor and −35.6–6.9 kV/m under the negative conductor | perception/behavior: activity (nursing, drinking, walking, lying, standing); distribution in panel |
more time was spent for nursing and drinking; fewer exposed than control cattle were observed in the central areas of pens but still most of the animals in the central area | experimental field study; same animals as in Angell et al. [44] |
| Gray et al. [37] | female B6C3F1 mice implanted with murine mammary adenocarcinoma (n = 44, 11 mice per group) | static EF of 450 kV/m; mice in restraining tubes while exposed for 4 h/day for 13 days; all mice received the chemotherapeutic agent adriamycin | therapeutic approach: tumor development |
greater tumor regression | also static MF and switching EF |
| Güler and Atalay [64] | guinea pig (n = 40 in total; 3 groups: n = 10 vertical static EF, n = 10 horizontal static EF, n = 20 control group) | static EF of 1.9 kV/m for 9 h/day for 3 days (horizontal and vertical) | organ parameters: hydroxyproline levels of liver, lungs and kidney |
increased hydroxyproline levels in liver, lungs and kidney; vertical EF more effective than horizontal | for liver, exactly the same values as in [65], possibly published twice |
| Güler et al. [65] | male guinea pig (n = 60, divided into 6 groups) | static EF of 0.9 to 1.9 kV/m for 9 h/day for 3 days (vertical and horizontal) | organ parameters: collagen synthesis (hydroxyproline level in the liver; histomorphological examination of liver slices) |
0.9 kV/m vertical and horizontal EF decreased the amount of hydroxyproline in the liver, while the 1.9 kV/m vertical and horizontal EF increased the amount of hydroxyproline | for 1.9 kV/m exactly the same values as in [64] for liver, possibly published twice |
| Güler et al. [66] | male guinea pigs (n = 70 in total, 6 experimental groups and 1 control group with n = 10 each) | static EF of 0.3, 0.9, and 1.8 kV/m for 8 h/day for 3 days (vertical and horizontal) | organ parameters: lipid peroxidation, superoxide dismutase activity in spleen and testis |
0.9 and 1.8 kV/m increased the lipid peroxidation and superoxide dismutase activity | |
| Güler et al. [67] | male guinea pigs (280 animals in total, 14 groups with n = 20 each) | static EF of 0.3, 0.6, 0.8, 0.9, 1, 1.35, 1.5, 1.8, and 1.9 kV/m for 8 h/day for 3 days (vertical) | organ parameters: oxidative stress in spleen and testes |
oxidative stress increased with increasing static EF strength | also studied AC EF; main focus was on developing a theoretic neural network |
| Güler et al. [71] | male guinea pig (n = 140, divided into 14 groups, additional 20 animals for control group) | static EF of 0.3, 0.6, 0.8, 1, 1.35, 1.5, and 1.8 kV/m for 8 h/day for 3 days (vertical and horizontal) | organ parameters and hematology/immunology: oxidative stress: lipid peroxidation and enzyme activity of superoxide dismutase in guinea pigs’ plasma, liver, lungs and kidney |
liver, kidney: significant increase of lipid peroxidation and SOD activity 1–1.8 kV/m; plasma: significant increase of lipid peroxidation and SOD activity 0.8–1.8 kV/m; lungs: significant increase of lipid peroxidation and SOD activity 1.35–1.8 kV/m; no difference between horizontal and vertical application of EF | also studied AC EF |
| Harutyunyan and Artsruni [75] | female albino rats (n = 72, divided into 3 groups) | static EF of 200 kV/m for 1 h or 6 h/day for 6 days | hematology/immunology: proteome changes in blood plasma |
increased lysozyme activity after 1 h and 6 h/day for 6 days; decrease of globular proteins coinciding with clotting acceleration after 1 h; attenuation of clotting-dependent proteome modifications reflected with incomplete coagulation after 6 h/day for 6 days | |
| Harutyunyan and Sahakyan [76] | male albino rats (n = 10 per group, 2 experimental groups and 2 control groups) | static EF of 200 kV/m for 1 h or 6 h/day for 6 days | hematology/immunology: oxidative processes in red blood cells and cell number |
after 1 h exposure: reduced number of red blood cells, increased oxidative stress and increased enzyme activities; after 6 days: increased number of red blood cells, oxidative stress parameters decreased or increased | |
| Kato et al. [48] | hindleg of anesthetized cats (n = 13) | static EF of 180–310 kV/m (both polarities) for 0.05, 0.2, 1.1, or 2 s for hair movement and for 1.5–3 min for action potential recording (sural nerve in 10 cats and sural, gastrocnemius, and articular nerves in 3 cats) | perception/behavior: hair movement; action potentials from afferent nerve fibers |
cat hairs were attracted to the upper electrode when exposed to static EF of 180 kV/m or more; afferent impulses were evoked from hair receptors that were probably stimulated by the hair movement; deeper receptors were not affected by the EF | |
| Kellogg and Yost [41] | female NAMRU mice (n = 200 in total, 8 groups, n = 25 each, in results partially less animals stated) | static EF of 1.8 kV/m plus 2*103 air ions/cm3; static EF of 2.4 kV/m plus 2*105air ions/cm3; static EF of 2 kV/m (both polarities, respectively); 2 control groups; exposure started with approx. 6 weeks until end of life (except for 6 h every 2 weeks when cages were cleaned) | hematology/immunology: mortality |
no effect found between static EF alone versus control group | main focus was on air ions; extension of [42, 43]; but unclear why different field strengths are reported. Duplicative publication of results from Kellogg et al (1985a, b) [42, 43]. In second year proteus vulgaris infection in all exposure groups caused severe gastroenteritis, splenic hypertrophy, occasional purulent salpingitis, and death. |
| Kellogg et al. [42] | female NAMRU mice (n = 200 in total, 8 groups, n = 25 each, in results partially less animals stated) | static EF of 1.75 kV/m plus 2*103 air ions/cm3; static EF of 1.98 kV/m plus 2*105 air ions/cm3; static EF of 2 kV/m (both polarities, respectively); 2 control groups; exposure started with approx. 6 weeks until end of life (in this article only first year reported) | hematology/immunology: blood parameters (serotonin, glucose, cholesterol, urea nitrogen, globulin) every three months |
increased mean glucose level in positive EF and decreased urea nitrogen in negative EF compared to overall mean values | main focus was on air ions; results for first year of a two year study, see [43] for second year; possibly mild vitamin deficiency |
| Kellogg et al. [43] | see Kellogg et al. [42] | see Kellogg et al. [42] (in this article only second year reported) | hematology/immunology: blood parameters (serotonin, glucose, cholesterol, urea nitrogen, globulin); survival rate organ parameters: organ parameters (weight, histologic changes) |
animals in static EF lived longer (no significance given) and increased mean glucose level in positive EF compared to overall mean value; no effect on organ weights | main focus was on air ions; results for second year of a two year study, see [42] for first year; possibly mild vitamin deficiency. In second year, proteus vulgaris infection in all exposure groups caused severe gastroenteritis, splenic hypertrophy, occasional purulent salpingitis, and death. |
| Krueger et al. [73] | NAMRU mice (n = 90–220 mice per group, 12 groups) | static EF of ca. 0.1 kV/m (ion depleted air or with 2.7-5*103 air ions) or static EF of 4–6 kV/m (ion depleted air or with 2.3-5*105 air ions) for up to 11 days | hematology/immunology: mortality after influenza infection |
no significant effect | main focus was on air ions |
| Lott and McCain [58] | male Sprague–Dawley rats (in total, n = 60) | surface electrodes measured EEG (n = 30) electrodes implanted in the brain measured hypothalamic activity (n = 30); 15 rats of each group were exposed to a pulsed EF and 15 to a static EF of 10 kV/m for 50 min during EEG recording; experiments were performed under anesthesia | brain/nervous system: brain activity and hypothalamic activity |
increased brain activity measured with surface electrodes and decreased hypothalamic activity (implanted electrodes); when EF was turned off, brain activity returned back to baseline before exposure | |
| Marino et al. [78] | female Swiss Ha/ICR mice (n = 5 per EF strength and exposure duration) | 2.7 kV/m and 10.7 kV/m (parallel to earth’s surface); 5.7 kV/m (perpendicular to the earth’s surface) for 7, 14, or 21 days | hematology/immunology: concentration of serum proteins (albumin, alpha-, beta-, gamma-protein) |
beta globulin increased under parallel and decreased under perpendicular exposure; albumin vice versa; gamma globulin increased under perpendicular exposure | |
| Marino et al. [69] | male Sprague–Dawley rats (7 different exposure groups with n = 12–20, corresponding control groups with n = 8–23); female Swiss Ha/ICR mice bearing Ehrlich ascites tumor cells (n = 7 exposed, n = 6 control) | rats: static vertical EF of 0.6, 2.8, 5.6, 19.7 kV/m and horizontal static EF of 0.3, 2.8, and 9.8 kV/m for 30 days; mice: horizontal static EF of 8–16 kV/m for 14 days | hematology/immunology (rats): body weight, serum protein concentration organ parameters (rats): histomorphology of different organs (lungs, liver, kidney), general examination genotoxicity (mice): chromosomal aberrations in tumor cells |
rats: secondary glaucoma (only vertical EF); altered serum protein concentration; no effects on organ histomorphology; mice: production of chromosomal abnormalities in tumor cells | |
| Mayyasi and Terry [51] | King-Holtzman rats (in total, n = 240, different age and sex groups; additional groups to test the influence of noise) | static EF of 1.6 and 16 kV/m for 5 h | perception/behavior: behavior, learning |
improved learning (less errors) and better swimming performance | |
| Mitchell et al. [79] | female mice (Swiss Ha/ICR) (n = 8–12 per group, data taken from results, number not stated in methods) | static EF in the range of 8 to 16 kV/m up to 15 weeks (horizontal and vertical) | genotoxicity: chromosomal aberrations in tumor cells |
increase in the percentage of abnormal chromosomes after 2 weeks of horizontal exposure; disappearance of the aberrant chromosomes after extended exposure | extension study of Marino et al. [69] |
| Möse and Fischer [52] (article in German) | white mice (n = 5 for locomotor activity and food/water consumption), n = 10 for rectal temperature, n = 12 for litter frequency, no number given for oxygen consumption of liver) | static EF of 23.8 kV/m for 15 days up to approx. 4 months (litter frequency) (mostly 15 to 20 days) | perception/behavior: locomotor activity, food/water consumption, rectal temperature reproduction/development: litter frequency organ parameters: oxygen consumption of liver pieces |
significant increase of locomotor activity, food and water consumption and rectal temperature; initially normal number of offspring, over the later period complete absence of offspring; no effect on oxygen consumption of liver pieces | not clear if peer-reviewed |
| Möse et al. [56] (article in German) |
rat and guinea pig (n = ?) | static EF of 23.8 kV/m for 6 days | organ parameters and brain/nervous System: serotonin concentration in uterus of rats, brain and ileum of guinea pigs |
reduced serotonin levels in brain and uterus, increased serotonin levels in ileum | not clear if peer-reviewed; contradictory statements if brain was taken from rats or guinea pigs |
| Möse et al. [68] (article in German) |
rat (uterus) and guinea pig (intestine) (n = ?) | static EF of 23.8 kV/m for 3–21 days | organ parameters: ability of isolated smooth muscles (intestine and uterus) to react to stimulating drugs |
smooth muscles reacted less to stimulating drugs | not clear if peer-reviewed |
| Möse et al. [60] (article in German) |
male NMRI mice (n = 25 per group, 3 groups: static EF, control group under ambient conditions, control group in Faraday cage) | static EF of 23.8 kV/m for 8 days | organ parameters: oxygen consumption of isolated liver pieces |
increased oxygen consumption under static EF exposure and decreased consumption under Faraday conditions in comparison to control group | not clear if peer-reviewed |
| Möse et al. [72] (article in German) | NMRI-Hahn mice (n = 10–15 per EF strength and condition) | static EF of 0.04, 0.2, 1, 5 and 24 kV/m for 15 days; in addition to control group under laboratory conditions also control in Faraday cage; mice were immunized with sheep erythrocytes at day 7 and 11 of exposure | hematology/immunology: immunization level (plaque formation on spleens, spleen weight, number of spleen cells, haemagglutination titers) |
immunization level increased under static EF exposure compared to a shielded environment in a Faraday cage | not clear if peer-reviewed |
| Okudan et al. [61] | male and female Wistar rats (progenies of 3 dams, already exposed during pregnancy); (n = 10 for static EF, n = 7 for control) | static EF of 10 kV/m for 28 days (14 days in utero and 14 days postnatal) | organ parameters: bone mineral density; bone mineral content |
decrease in bone mineral content and bone mineral density | also studied AC EF |
| Sahakyan et al. [77] | female rats (n = 120; divided into 2 groups) | static EF of 200 kV/m for 6 h/day for 6 days | hematology/immunology: lipid-protein interactions in rat erythrocyte membranes |
redistribution of membrane surface charge, conformational alterations of membrane integral proteins, increase of the immersion degree of the peripheral proteins | incomplete reference list |
| Xu et al. [57] | male ICR mice (n = 90, divided into 2 experimental groups and 1 control group of 30 animals each) | static EF of 2.3–15.4 kV/m (experimental group 1) and 9.2–21.85 kV/m (experimental group 2) from a HVDC line for 35 days except for raining and low temperature days | brain/nervous System: cognition: learning, memory; glutamate and GABA concentrations in the brain |
impaired memory abilities |