1 6 NEUROENDOCRINE SYSTEM 2 3 The pineal and pituitary neuroendocrine glands, both situated in the brain and intimately connected 4 with and controlled by the nervous system, release hormones into the blood stream which exert a profound 5 influence on body metabolism and physiology, particularly during development and reproduction, partly 6 via their influence on the release of hormones from other endocrine glands situated elsewhere in the body. 7 These studies have been reviewed by NIEHS (1998), IARC (2002), McKinlay et al., 2004 and recently by 8 AGNIR (2006). 9 10 The hypothesis, first suggested by Stevens (1987), that exposure to EMFs might reduce melatonin 11 secretion and thereby increase the risk of breast cancer has stimulated a number of human laboratory 12 studies and investigations of circulating melatonin levels in people exposed to EMFs in domestic or 13 occupational situations. 14 15 6.1 Volunteer studies 16 17 The majority of studies have investigated the effects of EMF exposure, mostly to power frequencies, 18 on circulating levels of the pineal hormone melatonin (or on the urinary excretion of a metabolite of 19 melatonin). Fewer studies have been carried out on circulating levels of pituitary hormones or other 20 hormones released from other endocrine glands such as the thyroid gland, adrenal cortex and reproductive 21 organs. 22 23 6.1.1 The pineal horm one: m elatonin 24 25 Melatonin is produced by the pineal gland in the brain in a distinct daily or circadian rhythm which is 26 governed by day length. It is implicated in the control of daily activities such as the sleep/wake cycle and in 27 seasonal rhythms such as those of reproduction in animals that show annual cycles of fertility and infertility. 28 Maximum serum levels occur during the night, and minimum levels during the day, even in nocturnally 29 active animals. Night-time peak values of serum melatonin in humans, however, can vary up to ten-fold 30 between individuals (Graham et al., 1996). It has been suggested that melatonin has a negative impact on 31 human reproductive physiology, but that any changes are slight compared to those seen in experimental 32 animals (Reiter, 1997). However, the overall evidence suggests that human melatonin rhythms are not 33 significantly delayed or suppressed by exposure to magnetic fields (NIEHS, 1998; AGNIR, 2001a; IARC, 34 2002; ICNIRP, 2003; although see Karasek and Lerchl, 2002). 35 36 6.1.1.1 Laboratory studies 37 38 Several laboratory studies have been carried out in which volunteers, screened for various factors 39 which might have influenced melatonin levels, were exposed or sham exposed overnight to circularly or 40 horizontally polarized intermittent or continuous power-frequency magnetic fields. No significant effects of 41 exposure on night-time serum melatonin levels were found (Graham et al., 1996, 1997; Selmaoui et al., 42 1996; Crasson et al., 2001; Kurokawa et al., 2003; W arman et al.., 2003a). Other studies, using the 43 excretion of the major urinary metabolite of melatonin as a surrogate measures of serum melatonin, also 44 found no effect (Selmaoui et al., 1996; Åkerstedt et al., 1999; Crasson et al., 2001; Graham et al., 2001a, 45 2001b). The use of the urinary excretion data complicates interpretation, however, since information 46 regarding any possible phase shift in melatonin production is lost. Griefahn (2001, 2002) found no effect of 47 exposure to 16.7 Hz magnetic fields on hourly saliva melatonin concentration. 48 49 Some positive effects have been reported, but these have generally not proved consistent. An initial 50 report (Graham et al., 1996) of a magnetic field-induced reduction of night-time serum melatonin levels in 51 volunteers with low basal melatonin levels was not confirmed using a larger number of volunteers. It is 52 possible that the initial positive findings were due to chance with a relatively small number of subjects. 53 However, the results of a study investigating the effects of night-time exposure to 60 Hz fields for four 54 nights (Graham et al., 2000) suggested a weak cumulative effect of exposure. Exposed subjects showed

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55 more intra-individual variability in the overnight levels of excretion of melatonin or its major metabolite on 56 night 4, although there was no overall effect on levels of melatonin. 57 58 W ood et al. (1998) exposed or sham exposed male subjects to an intermittent, circularly-polarised, 59 power-frequency magnetic field at various times during the dusk or night and measured the effect on night- 60 time serum melatonin levels. The results indicated that exposure prior to the night-time rise in serum 61 melatonin may have delayed the onset of the rise by about half an hour and may have reduced peak levels, 62 possibly in a sensitive sub-group of the study population. However, exposure categorisation was made post- 63 hoc (Wood et al, 1998) and the result can only be considered to be exploratory. Deleted: AGNIR 64 Deleted: , 2001 65 6.1.1.2 Residential and occupational studies 66 Deleted: preliminary 67 Several studies of responses have been carried out in people in residential or occupational situations. 68 These are naturally more realistic than laboratory studies but suffer from diminished control of possible 69 confounding factors, such as differences in lifestyle (W arman et al., 2003). W ith regard to domestic 70 exposure, one study (W ilson et al., 1990) has examined the possible effects on volunteers exposed at home 71 to pulsed EMFs generated by mains or DC-powered electric blankets over a 6œ10 week period. Overall, no 72 effect of exposure was seen on the urinary excretion of the major urinary metabolite of melatonin (aMT6s). 73 However, transient increases in night-time excretion were seen in the periods following the onset of a 74 period of electric blanket use and following the cessation of the period of electric blanket use in seven of 28 75 users of one type of electric blanket. This observation may, however, be rather weak given the lack of 76 correspondence of the effect with field condition and the fact that responsiveness was only identified 77 following the separate analysis of the excretion data from each of 42 volunteers, of which some analyses 78 may have turned out positive by chance (Hong et al.., 2001). In contrast, Hong et al. (2001) found no 79 significant field dependent effects on melatonin rhythms in nine men following 11 weeks of night-time 80 exposure. In this study, the urinary excretion of aMT6s was followed in five urine samples collected each 81 day. This study too, however, exercised very little control over possible confounding by environmental and 82 lifestyle factors. 83 84 Several more recent studies relating to residential exposure have been carried out. Davis et al. (2001) 85 reported lower nocturnal levels of melatonin, measured as the excretion of aMT6s, in women with a history 86 of breast cancer to be associated with higher bedroom magnetic field levels, once adjustment had been 87 made for hours of daylight, age, body mass index, current alcohol consumption and the use of certain 88 medications. Levallois et al. (2001) found no relation of night-time excretion of aMT6s to proximity of the 89 residence to power lines or to EMF exposure. There were, however, significantly stronger relations to age 90 and obesity (out of five variables for which the authors investigated effect modification) in women who 91 lived close to power lines than in those who lived more distantly. In a general review of all these studies, 92 IARC (2002) concluded that it was difficult to distinguish between the effects of magnetic fields and those 93 of other environmental factors. In a later study, Youngstedt et al. (2002) found no significant associations 94 between several measures of magnetic field exposure in bed (but not elsewhere) and various measures of 95 the urinary excretion of aMT6s in 242 adults, mostly women, aged 50œ81. 96 97 A number of other studies have examined urinary metabolite excretion in occupationally exposed 98 workers. For railway workers, Pfluger and Minder (1996) reported that early evening aMT6s excretion 99 (taken as an index of daytime serum melatonin levels) but not early morning excretion was decreased in 100 exposed workers. However, the authors noted that the effects of differences in daylight exposure, which 101 suppresses night-time melatonin, could not be excluded. In a study of electric utility workers, Burch et al. 102 (1998, 1999b) found no overall effect of exposure on night-time aMT6s excretion (taken as an index of 103 night-time melatonin levels) when considering mean levels of exposure. The authors did find lower levels 104 of night-time excretion in individuals exposed to temporally more stable magnetic fields, raising some 105 questions as to the interpretation of these data. A reduction in melatonin levels was found to be associated 106 with working near 3-phase conductors and not near 1-phase conductors, indicating a possible role of field 107 polarisation (Burch et al., 2000). Burch et al. (1999a) also found that reduction of aMT6s excretion was 108 associated with high geomagnetic activity. Juutilainen et al. (2000) found that occupational exposure to 109 magnetic fields produced by sewing machines did not affect the ratio of Friday morning/Monday morning 110 levels of aMT6s excretion, suggesting that weekends without workplace exposure did not change melatonin

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111 response. Average Thursday night excretion (Friday morning sample) was lower in exposed compared to 112 control workers. 113 114 In a study of a further group of male electrical utility workers, Burch et al. (2002) investigated 115 nocturnal excretion of aMT6s in men with high compared with low or medium workplace 60-Hz exposure. 116 After adjusting for light exposure at work, reduced melatonin levels were found within men with high 117 cellular phone use; the effect was not present in those with medium or no such phone use. Touitou et al. 118 (2003) found no effect on serum melatonin levels or the overnight excretion of urinary aMT6s in workers at 119 a high voltage substations chronically exposed to 50 Hz magnetic fields compared to white collar workers 120 from the same company. 121 122 A preliminary study by Arnetz and Berg (1996) of daytime serum melatonin levels in visual display 123 units (VDU) workers (sex not given) exposed to ELF and other frequency electromagnetic fields (values 124 not given) reported a slightly larger decrease during VDU work compared to leisure time. The biological 125 significance of this small daytime effect is not at all clear, given that serum melatonin peaks during the 126 night. 127 128 In a study by Lonne-Rahm et al.. (2000), 24 patients with electromagnetic hypersensitivity and 12 129 controls were exposed to a combination of stress situations and electric and magnetic fields from a VDU. 130 Blood samples were drawn for circulating levels of stress-related hormones (melatonin, prolactin, 131 adrenocorticotrophic hormone, neuropeptide Y and growth hormone). In double-blind tests, none of these 132 parameters responded to the fields, neither alone nor in combination with stress levels. 133 Table 46. Hum an m elatonin studies Endpoint Exposure Response Com m ent Authors ELF m agnetic fields Laboratory studies Night-time serum 60 Hz No effect. Possible W ell described and Graham et al., 1996 melatonin levels effect on low well planned double 1 or 20 µT, melatonin subjects blind study. intermittent not replicated in 8 h at night larger study.

Night-time serum 60 Hz No effect. W ell described and Graham et al., 1997 melatonin levels well planned double 20 µT, continuous blind study. 8 h at night Night-time serum 50 Hz No effect. W ell described and Selmaoui et al., melatonin levels well planned double 1996 and excretion of its 10 µT, continuous blind study. major urinary or intermittent metabolite 9 h at night (aMT6s). Night-time serum 50 Hz Possible delay and Double blind study; W ood et al., 1998 Deleted: Inconsistent, melatonin levels reduction of night- incomplete variable data 20 µT, sinusoidal or time melatonin volunteer square wave field, levels in sub-group. participation. intermittent 1.5œ4 h at night Night-time serum 50 Hz No effect. Double blind study. Åkerstedt et al., melatonin levels 1999 1 µT during sleep (24.00 to 08.00 h)

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Night-time serum 60 Hz No effect. W ell described and Graham et al., 2000 melatonin levels well planned double and excretion of 28.3 µT, continuous blind study. aMT6s. 8 h at night Night-time serum 50 Hz No effect. W ell described and Crasson et al., melatonin levels well planned double 2001 and excretion of 100 µT, continuous blind study. aMT6s or intermittent 30 min Night-time serum 60 Hz No effect. W ell described and Graham et al., melatonin levels in well planned double 2001a women 28.3 µT, blind study. intermittent 8 h at night Night-time serum 60 Hz No effect. W ell described and Graham et al., melatonin levels well planned double 2001b and excretion of 127 µT, continuous blind study. aMT6s or intermittent 8 h at night Night-time serum 60 Hz No effect. W ell described and Graham et al., melatonin levels well planned double 2001c and excretion of 28.3 µT, continuous blind study. aMT6s 8 h at night Salivary melatonin 16.7 Hz No effect. W ell described and Greifahn et al., levels well planned double 2001 200 µT blind study. 6 h at night Salivary melatonin 16.7 Hz No effect. W ell described and Greifahn et al., levels well planned double 2002 200 µT blind study. 6 h at night Night-time serum 50 Hz No effect. W ell described and Kurokawa et al., melatonin levels well planned double 2003b 20 µT, linearly blind study. polarised 8 h at night Night-time serum 50 Hz No effect. W ell described and W arman et al., melatonin levels well planned double 2003a 200 or 300 µT blind study. 2 h at night across rising phase of melatonin secretion ELF electric and m agnetic fields Domestic occupational studies Early morning 60 Hz No overall effect; Realistic, but W ilson et al., 1990 excretion of urinary transient increases concomitant lack of aMT6s EMFs generated by in 7/28 users of one control over lifestyle pulsed AC or DC type of blanket. etc. current supply to electric blankets 7œ10 weeks at night Urinary excretion of 50 Hz No effect. The only restriction Hong et al., 2001 aMT6s collected 5 on each subject‘s times per day ~1œ8 µT, electric usual daily activities ”sheet‘ over the were avoiding body overeating and 11 weeks at night strenuous exercise.

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Morning and 16.7 Hz Decreased evening Subjects acted as Pfluger and Minder, evening urinary 6-aMT6s levels but own controls; 1996 excretion of aMT6s approximately no effect on samples collected in railway workers. 20 µT mean value morning levels. No early autumn; fully in engine drivers dose-response described protocol. effect. Night-time and 60 Hz No overall effect W ell described Burch et al., 1998 early morning with exposure. study; some urinary excretion of ~0.1œ0.2 µT Temporally more adjustment for age, aMT6s in electric 24 hr at work, home stable fields at month of utility workers and during sleep home (using participation and calculated index) light exposure. associated with reduced nocturnal melatonin. Post work urinary 60 Hz No overall effect. Significant Burch et al., 1999 excretion of aMT6s Reduction in interaction with electric utility occupational aMT6s excretion in occupational light workers exposure over a workers exposed to exposure. week more stable fields during work. Night-time urinary 60 Hz Exposure-related Adjusted for Burch et al., 2000 excretion of aMT6s reduction in aMT6s workplace light in electric utility occupational excretion in exposure. workers exposure to workers exposed in magnetic fields substations or 3 phase environments for > 2 h. Night-time urinary 50 Hz Average aMT6s No difference in Juutilainen et al., excretion of aMT6s excretion lower in Friday to Monday 2000 in garment workers occupational exposed workers levels exposure to compared to office magnetic fields workers. Night-time urinary 50 Hz No overall effect. Adjusted for Levallois et al., excretion of aMT6s Significantly confounders. 2001 proximity to power stronger lines and/or association with exposure to age and obesity in domestic EMFs women living closer to power lines. Night-time urinary 60 Hz Borderline Significant Davis et al., 2001 excretion of aMT6s association with association with domestic exposure one measure of day length. to magnetic fields exposure in a subgroup of women. Night-time urinary 60 Hz Exposure-related Not present in Burch et al., 2002 excretion of aMT6s reduction in aMT6s workers with low or in electric utility occupational excretion in highly medium phone use. workers exposure to exposed workers magnetic fields associated with mobile phone use. 24 hr urinary 60 Hz No significant Potential Youngstedt et al., excretion of aMT6s associations confounders such 2002 domestic exposure between exposure as lighting, age and to magnetic fields and excretion. medication taken measured in the into account. bedroom only

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Serum melatonin geometric mean No effect compared Considerable care Touitou et al., 2003 levels and urinary fields of 0.1œ2.6 µT to levels in white- taken to avoid excretion of aMT6s collar workers. some confounders, in high-voltage sub- chronic e.g. study station workers occupational participants all non- exposure (1œ20 y) smokers. ELF and VLF electric and m agnetic fields Occupational studies Morning and Exposure details Decrease in serum Samples collected Arnetz and Berg, afternoon serum not given melatonin during Oct œ Feb. 1996 melatonin levels in the day was Experimental VDU workers statistically protocol briefly during one working significant at work described. No and one leisure (-0.9 ng/L) but not measured fields; no day. leisure (-0.8 ng/L). control over lifestyle etc. Circulating levels of 24 patients with No effect. Double blind study. Lonne-Rahm et al. stress-related electromagnetic (2000) hormones hypersensitivity and (melatonin, 12 controls prolactin, ACTH, neuropeptide Y and electric and growth hormone) magnetic fields from a VDU 134 135 136 6.1.2 Pituitary and other horm ones 137 138 Few studies of EMF effects on hormones of the pituitary and other endocrine glands have been 139 carried out. Principal pituitary hormones investigated in EMF studies include several hormones involved in 140 growth and body physiology, particularly thyroid-stimulating hormone (TSH) which controls the function 141 of the thyroid gland and the release of thyroxin; adrenocorticotrophic hormone (ACTH), which regulates 142 the function of the adrenal cortex and particularly the release of cortisol; and growth hormone (GH), which 143 affects body growth. Hormones released by the pituitary which have important sexual and reproductive 144 functions have also been studied, particularly follicle stimulating hormone (FSH), luteinising hormone (LH) 145 and prolactin. Both FSH and LH influence the function of the testis and the release of testosterone. 146 147 Three laboratory studies have investigated the possible effects of acute exposure to power-frequency 148 magnetic fields and power-frequency electric and magnetic fields on TSH, thyroxin, GH, cortisol, FSH, LH 149 and testosterone in men (Selmaoui et al., 1997; Maresh et al., 1988) and GH, cortisol and prolactin in men 150 and women (Åkerstedt et al., 1999). Overall, no effects were found. 151 152 An occupational study (Gamberale et al., 1989) of linesmen working on 'live' or 'dead' 400-kV power 153 lines found no effect of combined electric and magnetic field exposure over a working day on daytime 154 levels of serum TSH, cortisol, FSH, prolactin, LH and testosterone. A preliminary study (Arnetz and Berg, 155 1996) of VDU workers (sex not specified) exposed to ELF electric and magnetic fields (exposure not given) 156 reported elevated ACTH levels at work compared to leisure time; an effect, as the authors note, which is 157 probably attributable to work-related factors other than EMFs. 158 159 160 Table 47. Human pituitary and other endocrine studies Endpoint Exposure Response Comment Authors ELF magnetic fields Laboratory studies

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Night-time serum 50 Hz No differences W ell designed, Selmaoui et al.., levels of TSH, between exposed double-blind study. 1997 thyroxin, cortisol, 10 µT, continuous and sham-exposed. FSH and LH in or intermittent young men overnight from 23.00 to 08.00 h Night-time levels of 50 Hz No effect. Double blind study. Åkerstedt et al.., GH, cortisol and 1999 prolactin in men 1 µT and women during sleep (24.00 to 08.00 h) ELF electric and magnetic fields Laboratory study GH, cortisol and 60 Hz No effect. Double-blind study. Maresh et al.., 1988

testosterone in -1 young men 9 kV m and 20 µT 2 h following 45 min rest Occupational studies Day-time serum 50 Hz No effect. Counterbalanced Gamberale et al..,

TSH, cortisol, FSH, -1 presentation of 'live' 1989 prolactin, LH, and 2.8 kV m and 23.3 and 'dead' power testosterone in µT lines. linesmen working 4.5 h during on 'live' and 'dead' working day 400 kV power lines Morning and Exposure details Increase in serum Samples collected Arnetz and Berg, afternoon serum not given. ACTH during the Oct œ Feb. 1996 ACTH levels in day was statistically Experimental VDU workers significant at work protocol briefly during one working (0.6 pmol/L). but described. No and one leisure day not leisure (0.1 measured fields; no pmol/L) control over lifestyle etc. 161 162 6.2 Animal studies 163 164 A large number of studies have been carried out investigating the effects of EMF on circulating 165 melatonin levels in animals, because of the possible links between EMF and breast cancer. The impact of 166 melatonin on reproduction is particularly pronounced in seasonally breeding animals, where the effect 167 varies depending on the length of gestation in order to ensure that the offspring are born in late spring when 168 food is plentiful. Thus, for melatonin, the studies have been subdivided into those on laboratory rodents, 169 which have short gestational periods and seasonally breeding animals and primates, which are more closely 170 related to humans. 171 172 6.2.1 Melatonin 173 174 As indicated above, Stevens (1987) first suggested that chronic exposure to electric fields may reduce 175 melatonin secretion by the pineal gland and increase the risk of breast cancer. This followed reports 176 particularly by W ilson et al. (1981) of a significant overall reduction in pineal melatonin in rats chronically 177 exposed to 60 Hz electric fields and by Tamarkin et al. (1981) and Shah et al. (1984) of increased DMBA- 178 induced mammary carcinogenesis in rats with reduced melatonin levels. However, the significance of these 179 observations for humans is not clearly established. 180 181 6.2.1.1 Laboratory rodents 182

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183 Few studies have been carried out using mice. In a study by Picazo et al.. (1998) a significant 184 reduction in the night-time serum melatonin levels of mice exposed up to sexual maturity for four 185 generations to power frequency magnetic fields was observed. 186 187 A great many more studies have been carried out using rats. The effects of electric fields were 188 investigated before interest turned predominantly to magnetic fields. Several studies by one group of 189 authors (W ilson et al., 1981, 1983, 1986; Reiter et al., 1988) reported that the exposure to electric fields 190 significantly suppressed pineal melatonin and the activity of the N-acetyl-transferase enzyme (NAT) 191 important in the synthesis of melatonin in the pineal gland. This effect was transient, appearing within three 192 weeks of exposure but recovered within three days following the cessation of exposure. Subsequently, 193 however, the same laboratory (Sasser et al., 1991) reported in an abstract that it was unable to reproduce the 194 E-field-induced reduction in pineal melatonin. Another laboratory (Grota et al., 1994) also reported that 195 exposure to power-frequency electric fields had no effect on pineal melatonin levels or NAT activity, 196 although serum melatonin levels were significantly depressed. 197 198 Further work used rats to investigate the effect of exposure to power-frequency magnetic fields. An 199 early study by Martínez-Soriano et al. (1992) was inconclusive because of technical difficulties. A more 200 extensive series of tests has been carried out by Kato et al. (1993, 1994a, 1994b, 1994c, 1994d, summarised 201 in Kato and Shigemitsu, 1997). They studied the effects of exposure to circularly- or linearly-polarised 202 power-frequency magnetic fields of up to 250 mT for up to 6 weeks on pineal and serum melatonin levels in 203 male rats. These authors reported that exposure to circularly polarised but not linearly polarised field 204 reduced night-time serum and pineal melatonin levels. However, a major difficulty with the interpretation 205 of many of the studies by this group was that the sham-exposed groups were sometimes treated as a ”low 206 dose‘ exposed groups because they were exposed to stray magnetic fields (of less than 2%) generated by 207 the exposure system. Thus, statistical comparison was sometimes made with historical controls. Such 208 procedures fail to allow for the inter-experimental variability that was reported in replicate studies by Kato 209 and Shigemitsu (1997). Results from four further groups who have investigated magnetic-field effects on 210 serum and pineal melatonin levels in rats (Selmaoui and Touitou, 1995, 1999; Bakos et al., 1995, 1997, 211 1999; Mevissen et al., 1996; Löscher et al., 1998; John et al., 1998) were inconsistent but mostly negative. 212 213 214 Table 48. Melatonin studies in laboratory rodents Endpoint Exposure Response Comment Authors ELF electric fields Rats Night-time pineal 60 Hz Reduced pineal Data combined in W ilson et al.. 1981 melatonin levels melatonin and NAT one experiment 1.7œ1.9 kV m -1 (not and NAT enzyme -1 activity. because of activity in adult rats 65 kV m due to variability. equipment failure) 20 h per day for 30 days Night-time pineal 60 Hz Pineal melatonin W ilson et al.. 1986 melatonin levels and NAT activity 65 kV m -1 (39 kV m - and NAT enzyme 1 reduced within 3 activity in adult rats effective) weeks exposure; up to 4 weeks recovered 3 days after exposure. Night-time pineal 60 Hz Night-time peak No simple dose- Reiter et al.. 1988 melatonin levels in reduced and response 10, 65 or 130 kV m - adult rats 1 delayed in exposed relationship. animals. during gestation and 23 days postnatally

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Night-time pineal 60 Hz No effect on night- Meeting abstract, Sasser et al.. 1991 melatonin levels in -1 time peak pineal but included adult rats 65 kV m melatonin. because it 20 h per day for 30 attempted to days replicate earlier studies from this group. Night-time pineal 60 Hz No effect on night- Similar to W ilson et Grota et al.. 1994 melatonin and NAT -1 time melatonin and al.. 1986. activity and serum 10 or 65 kV m NAT; serum melatonin in adult melatonin down 20 h per day for 30 -1 rats days after 65 kV m . ELF magnetic Fields Mice Serum melatonin 50 Hz Reduced night-time Experimental Picazo et al.. 1998 levels in 4th gen. levels. procedures not fully male mice 15 µT described. for 4 generations Rats Serum melatonin 50 Hz Serum melatonin Technical Martinez Soriano et levels in adult rats reduced on day 15; difficulties; brief al.. 1992 5 mT no values for days description of 30 min during the 1, 7 or 21. method. morning for 1, 3, 7, 15 and 21 days Pineal and serum 50 Hz Night-time and Questionable Kato et al.. 1993 melatonin levels in some daytime comparisons to adult rats 1, 5, 50 or 250 µT, reductions in serum historical controls. circularly polarised and pineal 6 weeks melatonin. Serum melatonin 50 Hz Night-time Comparison to Kato et al.. 1994a levels in adult rats melatonin levels sham exposed. 1 µT, circularly reduced, returning polarised to normal within one 6 weeks week. Pineal and serum 50 Hz Night-time pineal Comparison to Kato et al.. 1994b melatonin levels in and serum levels sham exposed and adult rats 1 µT, circularly reduced. historical controls. polarised 6 weeks Serum melatonin 50 Hz No effect. Comparison to Kato et al.. 1994c levels in adult rats sham exposed and 1 µT, horizontally or historical controls. vertically polarised 6 weeks ”Antigonadotrophic‘ 50 Hz circularly No effect. Comparison with Kato et al.. 1994d effect of melatonin polarised 1, 5, or 50 sham exposed. on serum mT for 6 weeks testosterone in adult rats Night-time serum 50 Hz Reduced melatonin Selmaoui and melatonin levels and NAT activity Touitou, 1995 and pineal NAT 1, 10 or 100 µT after 100 µT (acute) activity in adult rats 12 h once, or 18 h and 10 and 100 µT per day for 30 days (chronic).

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Night-time serum 50 Hz Reduced melatonin Selmaoui and melatonin levels and NAT activity in Touitou, 1999 and pineal NAT 100 µT young rats but not

activity in young (9 18 h per day for one old rats. wks) and aged (23 week mos) rats Night-time excretion 50 Hz No significant Bakos et al.. 1995, of melatonin urinary effects compared to 1997, 1999 metabolite in adult 1, 5, 100 or 500 µT base-line pre- rats 24 h exposure controls. Night-time pineal 50 Hz No effect. A small part of a Mevissen et al.. melatonin levels in larger, well planned 1996 non-DMBA treated 10 µT mammary tumour adult rats 13 weeks study. Night-time serum 50 Hz No consistent The few positive Löscher et al.. 1998 melatonin, levels in effects on effects could not be SD rats 100 µT melatonin. replicated. 1 day, 1, 2, 4, 8 or 13 weeks Night-time excretion 60 Hz No effect. John et al.. 1998 of melatonin urinary metabolite in adult 1 mT rats continuous for 10 days or 6 weeks intermittent for 2 days 215 216 6.2.1.2 Seasonal breeders 217 218 Four different laboratories have investigated the effects of EMF exposure on pineal activity, serum 219 melatonin levels and reproductive development in animals which breed seasonally. A series of studies by 220 Yellon and colleagues (Yellon, 1994; Yellon, 1996; Truong et al., 1996; Truong and Yellon, 1997; Yellon 221 and Truong, 1998) investigated magnetic field exposure o f Djungarian hamsters in which the duration of 222 melatonin secretion during the shortening days of autumn and winter inhibit reproductive activity. These 223 authors reported that a brief exposure to a power-frequency magnetic field 2 h before the onset of darkness 224 reduced and delayed the night-time rise in serum and pineal melatonin. In expanded replicate studies no 225 reduction in melatonin was observed and no effect was seen on reproductive development. In contrast to 226 this work, Niehaus et al. (1997) reported that the chronic exposure of Djungarian hamsters to ”rectangular‘ 227 power-frequency magnetic fields resulted in increased testis cell numbers and night-time levels of serum 228 melatonin. However, the results are not easy to interpret: increased melatonin levels in the Djungarian 229 hamster are usually accompanied by decreased testicular activity. W ilson et al. (1999) investigated the 230 effect of exposure to power-frequency magnetic fields on pineal melatonin levels, serum prolactin levels 231 and testicular and seminal vesicle weights in Djungarian hamsters moved to a ”short day‘ light regime in 232 order to induce sexual regression. Night-time pineal melatonin levels were reduced following acute 233 exposure but this effect diminished with prolonged exposure. In contrast, induced sexual regression, as 234 indicated by the testicular and seminal vesicle weights, seemed to be enhanced rather than diminished by 235 prolonged magnetic field exposure, suggesting a possible stress response. 236 237 The third set of studies of EMF effects on seasonal breeders concerned Suffolk sheep; these have a 238 long gestational period and become reproductively active in the autumn, as day length shortens. In two 239 replicate studies (Lee et al., 1993, 1995), Suffolk lambs were exposed outdoors to the magnetic fields 240 generated by overhead transmission lines for about 10 months. The authors reported no effect of exposure 241 on serum melatonin levels or on the onset of puberty. 242 243 244 Table 49. Melatonin levels in seasonally breeding animals

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Endpoint Exposure Response Comment Authors ELF magnetic fields Djungarian hamsters Night-time pineal 60 Hz Reduced and Considerable Yellon, 1994 and serum delayed night-time variability between melatonin levels 100 µT peak; diminished replicate studies. and absent in 2nd 15 min, 2 h before rd dark and 3 replicates. Night-time pineal 60 Hz Reduced and Considerable Yellon, 1996 and serum delayed night-time variability between melatonin levels; 100 µT peak; diminished in replicate studies. nd adult male 15 min, 2 h before 2 replicate study; reproductive status dark; second study no effect on over 3-week period melatonin-induced sexual atrophy. Night-time pineal 60 Hz No effect on pineal Second part of Yellon, 1996 and serum or serum melatonin; above paper. melatonin levels; 100 µT no effect on adult male 15 min, 2 h before melatonin-induced reproductive status dark for 3 weeks sexual atrophy. Night-time pineal 60 Hz Reduced and Considerable Truong et al.. 1996 and serum delayed night-time variability in melatonin levels; 100 µT peak; absent in 2nd melatonin levels male puberty, 15 min, 2 h before replicate study. No between replicate assessed by testes dark from 16œ25 effect on studies. weight days of age development of puberty. Night-time pineal 60 Hz No effect. Truong and Yellon, 1997 and serum melatonin levels 10 or 100 µT (continuous) or 100 µT (intermittent) 15 or 60 min before or after onset of dark period Night-time rise in 60 Hz No effect, even in Yellon and Truong, 1998 pineal and serum absence of melatonin levels; 100 µT photoperiodic cue. testes weight 15 min per day, in complete darkness, for up to 21 days Night-time pineal 50 Hz Increased cell Animals on long day Niehaus et al.. 1997 and serum number and night- schedule; difficult melatonin levels; 450 µT (peak) time serum interpretation. testis cell numbers sinusoidal or 360 µT melatonin levels (peak) rectangular after rectangular 56 days field exposure. Night-time pineal 60 Hz Reduced pineal Authors suggest a W ilson et al.. 1999 melatonin levels, melatonin after 15 stress-like effect. and testis and 100 or 500 NT, min exposure; seminal vesicle continuous and/or reduced gonad weights in short day intermittent weight but not (regressed) animals starting 30 min or 2 melatonin after 42 h before onset of day exposure. darkness; for up to 3 h up to 42 days ELF electric and magnetic fields Suffolk sheep

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Night-time serum 60 Hz No effect of EMFs; Two replicate Lee et al.. 1993, 1995

melatonin levels -1 strong seasonal studies; open air and female puberty, 6 kV m and 4 µT, effects. conditions. detected by rise in generated by serum progesterone overhead power lines 10 months 245 246 247 6.2.1.3 Non human primates 248 249 Non-human primates are close, in evolutionary terms, to humans and share many similar 250 characteristics. Rogers et al. (1995a; 1995b) studied responses in male baboons. Generally, no effect on 251 night-time serum melatonin levels was seen (Rogers et al., 1995a). However, a preliminary study (Rogers 252 et al., 1995b), based on data from only two baboons, reported that exposure to an irregular, intermittent 253 sequence of combined electric and magnetic fields in which switching transients were generated, resulted in 254 a marked suppression of the night-time rise in melatonin. 255 256 257 Table 50. Melatonin levels in non-human primates Endpoint Exposure Response Comment Authors ELF electric and magnetic fields Night-time serum 60 Hz No effect. Rogers et al.. 1995a

melatonin level in -1 baboons 6 kV m and 50 µT, 6 weeks 30 kV m -1 and 100 µT, 3 weeks Night-time serum 60 Hz Reduced serum Preliminary study on Rogers et al.. 1995b

melatonin level in -1 melatonin levels. two baboons. baboons 6 kV m and 50 µT or 30 kV m -1 and 100 µT irregular and intermittent sequence for 3 weeks 258 259 260 6.2.2 The pituitary and other horm ones 261 262 The pituitary gland, like the pineal gland, is intimately connected to the nervous system. It releases 263 hormones into the blood stream either from specialised neurosecretory cells originating in the 264 hypothalamus region of the brain, or from the cells in the pituitary whose function is under the control of 265 such neurosecretory cells via factors released into a specialised hypothalamic-pituitary portal system. The 266 main pituitary hormones investigated in EMF studies include several involved in growth and body 267 physiology, particularly thyroid-stimulating hormone (TSH), which controls the function of the thyroid 268 gland, adrenocorticotrophic hormone (ACTH), which regulates the function of the adrenal cortex, and 269 growth hormone (GH), which affects body growth, and hormones which have important sexual and 270 reproductive functions, particularly follicle stimulating hormone (FSH), luteinising hormone (LH) and 271 prolactin (or luteotrophic hormone). 272 273 6.2.2.1 Pituitary-adrenal effects 274 275 The possibility that EMF might act as a stressor has been investigated in a number of studies that have 276 examined possible effects of EMF exposure on the release of hormones involved in stress responses, 277 particularly ACTH and cortisol and/or corticosterone released from the adrenal cortex. For ELF electric

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278 fields, Hackman and Graves (1981) reported a transient (minutes) increase in serum corticosterone levels in 279 young rats immediately following the onset of exposure to levels greatly in excess of the electric field 280 perception threshold; however, exposure for longer durations had no effect. A lack of effect of prolonged 281 exposure to ELF fields has been reported by other authors on ACTH levels (Portet and Cabanes, 1988) and 282 on cortisol/corticosterone levels (Free et al., 1981; Quinlan et al., 1985; Portet and Cabanes, 1988; 283 Thompson et al., 1995; Burchard et al., 1996). Two studies, both limited by small numbers of animals, 284 reported positive effects of exposure to power frequency electric (de Bruyn and de Jager, 1994) and 285 magnetic (Picazo et al., 1996) fields on the diurnal rhythmicity of cortisol/corticosterone levels in mice. 286 287 6.2.2.2 Other endocrine studies 288 289 Studies of TSH levels and of the thyroid hormones (T3 and T4), which have a major influence on 290 metabolic functions, have been carried out in three studies. No effect on serum TSH levels was found (Free 291 et al., 1981; Quinlan et al., 1985; Portet and Cabanes, 1988); in addition, no effects were reported on serum 292 thyroxin (T3 and T4) levels in rabbits (Portet and Cabanes, 1988), but T3 levels were reduced in rats (Portet 293 and Cabanes, 1988). Growth hormone levels were reported to increase in rats intermittently exposed for 3 h 294 (Quinlan et al., 1985), but were reported to be unaffected following prolonged (3œ18 weeks) electric-field 295 exposure at the same level (Free et al., 1981). 296 297 Similarly negative or inconsistent data exist concerning possible effects of ELF field exposure on 298 hormones associated with reproduction and sexual development. Prolactin, FSH, LH and testosterone levels 299 in rats were reported unaffected by exposure to power-frequency electric fields (Quinlan et al., 1985; 300 Margonato et al., 1993); similar results for prolactin were reported by Free et al. (1981), but variable effects 301 on FSH levels were seen during development and serum testosterone levels were reported to be decreased 302 in adults. In contrast, an increase in serum prolactin levels was reported in Djungarian hamsters briefly 303 exposed to ELF magnetic fields (W ilson et al., 1999), and an increase in serum progesterone in cattle 304 exposed to combined electric and magnetic fields (Burchard, 1996). In a subsequent study, Burchard et al. 305 (2004) found that continuous exposure to an electric field for 4 weeks had no effect on circulating levels of 306 progesterone, prolactin and insulin-like growth factor. 307 308 309 Table 51. The pituitary and other hormones Endpoint Exposure Response Comment Authors ELF electric fields Mice Serum levels of 60 Hz Elevated daytime but Small numbers and De Bruyn and de

corticosterone in -1 not night-time levels variable daytime Jager, 1994 adult male mice 10 kV m compared to controls. data. 22 h per day for 6 generations Rats Serum levels of TSH, 60 Hz Testosterone levels Variable changes in Free et al.. 1981

GH, FSH, prolactin, -1 significantly hormone plasma LH, corticosterone 100 kV m decreased after 120 concentration during and testosterone in (unadjusted) days; no other development. young and adult male 20 h per day for 30 consistent effects in rats and/or 120 days adults; significant (adults) or from 20œ changes in FSH 56 days of age levels in young rats. (young)

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Serum corticosterone 60 Hz Transient increase in Positive control Hackman and

levels in adult male -1 serum levels at onset group; incomplete Graves, 1981 mice. 25 or 50 kV m of exposure. presentation of data. 5 min per day up to 42 days Serum levels of TSH, 60 Hz Increase in GH levels Care taken to avoid Quinlan et al.. 1985

GH, prolactin and -1 in rats exposed extraneous corticosterone in 100 kV m , intermittent for 3 h, confounding factors. adult male rats continuous or but not 1 h; no other intermittent effects. 1 or 3 h Serum levels of TSH, 50 Hz No significant effects Portet and Cabanes, ACTH, thyroxin (T3 + except T3 (but not T4) 1988 50 kV m -1 T4) and reduced. corticosterone in 8 h per day for 28 young male rats days Serum levels of FSH, 50 Hz No significant effects. Variable data. Margonato et al..

LH and testosterone œ1 1993 in adult male rats 25 or 100 kV m 8 h per day for up to 38 weeks Rabbits Serum levels of GH, 50 Hz No significant effects. Portet and Cabanes, ACTH, thyroxin (T3 + 1988 50 kV m -1 T4) and corticosterone (and 16 h per day from cortisol) in 6 week old last 2 weeks of rabbits gestation to 6 weeks after birth ELF mMagnetic fields Mice Serum cortisol levels 50 Hz Loss of diurnal Small numbers per Picazo et al.. 1996 in adult male mice rhythmicity; daytime group. 15 µT levels fell and night- 14 weeks prior to time levels rose. conception, gestation and 10 weeks post gestation Djungarian hamsters Serum levels of 60 Hz Prolactin levels Incomplete W ilson et al.. 1999 prolactin in adult elevated 4 h after presentation of male Djungarian 100 µT dark following acute prolactin data. hamsters on long or 15 min before dark but not chronic short days exposure. 100 µT, intermittent / continuous 45 min per day before dark for 16œ42 days 310 311 312 6.3 In vitro studies 313 314 In vitro studies of exposure to EMFs divide into two types of investigation: effects on the production 315 of melatonin by cells from the pineal gland; and effects on the action of melatonin on cells. Some studies 316 have investigated the effects of static magnetic fields, but these have not been reviewed here. 317

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318 6.3.1 Effects on m elatonin production in vitro 319 320 There are only a few studies that have investigated the effect of magnetic fields on melatonin 321 production in vitro. All used rodents as the source of pineal gland cells but there are marked differences in 322 their methodology. Most used power frequencies (50 or 60 Hz), but the field strength (50 µTœ1 mT) and 323 duration (1œ12 h) differ between the studies. Direct measures include melatonin content or melatonin 324 release from cells. Indirect measures can be made from the activity of N-acetyltransferase (NAT), an 325 enzyme involved in the synthesis of melatonin, or of hydroxyindole-O-methyltransferase (HIOMT), an 326 enzyme responsible for methylation and hence release of melatonin from the cells. Most of the studies have 327 stimulated pharmacologically the production of melatonin in the isolated glands by the addition of 328 noradrenaline (NA) or isoproterenol. 329 330 Lerchl et al. (1991) exposed pineal glands from young rats, removed during the day light period, to a 331 combination of a static field (44 µT) and a low frequency magnetic field (44 µT at 33.7 Hz), the theoretical 332 conditions for cyclotron resonance of the calcium ion. Exposure caused a reduction in NAT activity, 333 melatonin production and melatonin release into the culture medium. Rosen et al. (1998) also used pineal 334 glands from the rat, but this study was different to the other studies in that the pineal gland was separated 335 into individual cells. The overall result was that magnetic field exposure caused a statistically significant 336 46% reduction in stimulated melatonin release. Chacon (2000) used rat pineal glands to study NAT activity. 337 The enzyme activity decreased by approximately 20% after 1 h exposure to the highest field strength tested 338 (1000 µT) but was not significantly altered by field strengths of 10 or 100 µT. The interpretation of the 339 result may be complicated by the removal of the pineal gland during the rats‘ dark period, which may have 340 had an effect on melatonin synthesis and a confounding effect on the result. 341 342 A study by Brendel et al. (2000) used pineal glands from the Djungarian hamster. It also differed 343 from the previous studies in that the glands were maintained in a flow-system, so that changes of melatonin 344 released from the glands could be monitored throughout the duration of the experiment. The experimental 345 protocol appears to have been well-designed with random allocation of exposure or sham to identical 346 exposure systems and the experiments run blind. The authors concluded that EMF inhibited melatonin 347 production in both the 50 Hz and 16.67 Hz experiments. However there is only one time point in 1 of 4 348 experiments that the melatonin released is statistically different from the sham exposed. Similarly, a study 349 by Tripp et al. (2003) used a flow system to detect changes of melatonin release during the course of the 350 exposure. The exposure was for 4 h to a circularly polarised magnetic fields at 500 µT, 50 Hz. Samples 351 were taken every 30 min; the process used remote collection to avoid potential artefacts involved in manual 352 collection. The glands were not stimulated pharmacologically and no field-dependent changes in melatonin 353 release were detected. 354 355 Lewy et al. (2003) used rat pineal glands isolated in the morning and hence during the 12 h light 356 period. The glands were exposed for 4 h to a 50 Hz magnetic field at 1 mT. The activity of enzymes NAT 357 and HIOMT was measured, as well as the release of melatonin into the incubation liquid. In contrast to 358 many other studies, field exposure given simultaneously with NA or 30 min prior to NA administration 359 caused a significant increase (approximately 50%) in melatonin release. There was no change in melatonin 360 release due to field exposure in glands that had not been stimulated by NA. 361 362 6.3.2 Effects on the action of m elatonin in vitro 363 364 The main interest in this area was caused by the claim that exposure to magnetic fields can block the 365 inhibitory effect of melatonin on growth of breast cancer cells. The original work was reported by Liburdy 366 et al. (1993) in a study using a human oestrogen-responsive breast cancer cell line (MCF-7). They found 367 that the proliferation of MCF-7 cells can be slowed by the addition of physiological concentrations of 368 melatonin (1 nM). However, if the cells are simultaneously exposed to a 60 Hz, 1.2 µT magnetic field, then 369 the effect of melatonin on the rate of proliferation is reduced. The effects are fairly small and can only been 370 seen after 7 days in culture. They suggested that the magnetic field disrupted either the ligand/receptor 371 interaction or the subsequent signalling pathway. The authors found no effect at a magnetic field strength of 372 0.2 mT and suggested a threshold between 0.2 mT and 1.2 mT. No effect was seen using field exposure 373 alone. A similar effect of a 60 Hz field was reported by Harland and Liburdy (1997) but using tamoxifen

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374 (100 nM) rather than melatonin to bring about the initial inhibition. The effect has been reported in other 375 cell lines, namely a second breast cancer cell line, T47D, (Harland et al., 1998) and a human glioma cell 376 line 5F757 (Afzal and Liburdy, 1998). However, as previously noted (NIEHS, 1998; AGNIR, 2001), the 377 effect seen in the initial study (Liburdy et al., 1993) was small (10œ20 % growth over 7 days) and some 378 concern was noted regarding the robustness of the effect. 379 380 Blackman et al. (2001) set out to replicate these findings, using the MCF-7 cells supplied by Liburdy, 381 but with a modified and improved experimental protocol. The inhibition of MCF-7 growth by melatonin, 382 reported by Liburdy et al., (1993), was not significant. Tamoxifen caused a 25% inhibition in cell numbers, 383 which was reduced to a 13% inhibition by exposure to a 60 Hz magnetic field at 1.2 µT. This result 384 confirmed the results reported by Harland and Liburdy (1997), in which a 40% inhibition was reduced to 385 25% by EMF exposure. A later study by Ishido et al. (2001) exposed MCF-7 cells (supplied by Liburdy) to 386 0, 1.2 or 100 µT at 50 Hz for 7 days. Melatonin at concentrations of 10-9 M or higher induced inhibition of 387 intracellular cyclic AMP which was blocked by exposure to a 50 Hz field at 100 µT. Similarly DNA 388 synthesis, which was inhibited by 10-11 M melatonin levels, was partially released by exposure at 1.2 mT. 389 390 However, although the MCF-7 cell line has undoubtedly provided a useful model to investigate 391 effects on isolated breast cancer cells it is only one possible model in cells that have been separated from 392 their natural environment and therefore its implication for breast cancer in general is limited. The cell line 393 is rather heterogeneous; different subclones show different growth characteristics (eg Morris et al., 1998; Deleted: l 394 Luben and Morgen, 1998) raising the possibility that the effects were specific to individual subclone Deleted: . 395 phenotypes. The effects of stronger magnetic fields were studied by Leman et al. (2001) in three breast 396 cancer cell lines that were reported to have different metastatic capabilities: MDA-MB-435 cells, which 397 were considered to be highly metastatic, MDA-MB-231 cells which were considered to be weakly 398 metastatic, and MCF-7 cells, which were considered as non-metastatic. Only the weakly and non-metastatic 399 cells responded to melatonin and optimum inhibition was achieved at 1mM concentration of melatonin (a 400 million-fold higher than used in the Liburdy study). Exposure for 1 h to a pulsed field at 300 µT repeated 401 for 3 days had no effect on growth in either cell line. 402 Table 52. Magnetic field effects on melatonin Endpoint Exposure Response Comment Authors Effects on melatonin production in vitro NA stimulation of Static field and 33.7 Reduced production Opposite to expected Lerchl et al., 1991 melatonin production Hz, 44 µT and release. effect of calcium ions. and release from rat pineal gland 2.5 h NA stimulation of 60 Hz Reduced release. Rosen et al., 1998 melatonin release from rat pineal cells 50 µT 12 h NAT activity in rat 50 Hz Decreased NAT Chacon 2000 pineal glands activity at the highest 10, 100 µT or 1 mT exposure level only. 1 h Isoproterenol 50 Hz or 16.7 Hz Melatonin production Continuous flow Brendel et al., 2000 stimulation of reduced. system used allowing melatonin production 86 µT temporal resolution of in Djungarian hamster 8 h any effect. pineal gland Melatonin release 50 Hz No effect on Continuous flow Tripp et al., 2003 from rat pineal gland melatonin release. system used allowing 0.5 mT temporal resolution of 4 h any effect.

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NA stimulated 50 Hz Melatonin release Lewy et al., 2003 Melatonin release increase. from rat pineal gland. 1 mT 4 h Effects on cell responses to melatonin or tamoxifen in vitro Melatonin inhibition of 60 Hz EMF exposure Small (10œ20% ) Liburdy et al., 1993 MCF-7 cell growth reduced growth effect. 1.2 µT inhibition. 7 days Tamoxifen inhibition 60 Hz EMF exposure Harland and Liburdy, of MCF-7 cell growth reduced growth 1997 1.2 µT inhibition. 7 days Melatonin or 60 Hz EMF exposure Melatonin did not Blackman et al., 2001 Tamoxifen inhibition reduced growth inhibit MCF-7 growth of MCF-7 cell growth 1.2 µT inhibition by significantly. 7 days tamoxifen. Melatonin inhibition of 50 Hz Reduction of Ishido et al., 2001 cAMP and DNA melatonin induced synthesis in MCF-7 1.2 or 100 µT inhibition. cells 7 days Melatonin inhibition of 2 Hz pulsed field; No effect on cell Leman et al., 2001 growth of 3 breast pulse width 20 ms growth. cancer cell lines including MCF-7 0.3 mT 1 h per day for 3 days 403 404 405 6.4 Conclusions 406 Deleted: evidence in humans 407 The results of volunteer studies as well as residential and occupational studies suggests that the from laboratory 408 neuroendocrine system is not adversely affected by exposure to power-frequency electric and/or magnetic Deleted: and the overall 409 fields. This applies particularly to circulating levels of specific hormones of the neuroendocrine system, effects indictated no 410 including melatonin, released by the pineal gland, and a number of hormones involved in the control of association between exposure, 411 body metabolism and physiology released by the pituitary gland. Subtle differences were sometimes even up to 300 µT, and 412 observed in the timing of melatonin release or associated with certain characteristics of exposure, but these hormone levels. It is also 413 results were not consistent. It is very difficult to eliminate possible confounding by a variety of important to recognize in assessing such subtle and 414 environmental and lifestyle factors that might also affect hormone levels. Most laboratory studies of the inconsistent results that 415 effects of ELF exposure on night-time melatonin levels in volunteers found no effect when care was taken 416 to control possible confounding. Deleted: i 417 Deleted: , but not all, 418 From the large number of animal studies investigating power-frequency EMF effects on rat pineal and Deleted: to 50 or 60-Hz 419 serum melatonin levels, some reported that exposure resulted in night-time suppression of melatonin. electric or magnetic fields 420 Changes in melatonin level first observed in early studies of electric-field exposures up to 100 kV m-1 could 421 not be replicated. The finding from a series of more recent studies reporting that circularly-polarised Deleted: Melatonin 422 magnetic fields suppressed night-time melatonin levels was weakened by inappropriate comparisons Deleted: changes 423 between exposed animals and historical controls. The data from other magnetic fields experiments in 424 laboratory rodents, covering intensity levels over three orders of magnitude from a few microtesla to 5 mT, Deleted: no changes as well as 425 were equivocal, with some results showing depression of melatonin but others showing no change. In 426 seasonally breeding animals, the evidence for an effect of exposure to power-frequency fields on melatonin Deleted: T 427 levels and melatonin-dependent reproductive status is predominantly negative. No convincing effect on Deleted: EMFs 428 melatonin levels has been seen in a study of non-human primates chronically exposed to power-frequency 429 fields, although a preliminary study using two animals reported melatonin suppression in response to an Deleted: in seasonally breeding animals, Djungarian 430 irregular and intermittent exposure. hamsters and Suffolk sheep, 431 Deleted: EMFs

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432 W ith the possible exception of transient (minutes duration) stress following the onset of ELF electric 433 field exposure at levels significantly above perception thresholds, no consistent effects have been seen in 434 the stress-related hormones of the pituitary-adrenal axis in a variety of mammalian species. Similarly, 435 mostly negative or inconsistent effects have been seen in amounts of growth hormone, levels of hormones 436 involved in controlling metabolic activity or associated with the control of reproduction and sexual 437 development, but few studies have been carried out. 438 439 The effects of ELF exposure on melatonin production or release in isolated pineal glands was variable, Deleted: . However 440 although relatively few in vitro studies have been undertaken. The evidence that ELF exposure interferes Deleted: M 441 with the action of melatonin on breast cancer cells in vitro is intriguing and there appears to be some 442 supporting evidence in terms of independent replication using MCF-7 cells. However this system suffers Deleted: effect appears to 443 from the disadvantage that the cell lines frequenctly show genotypic and phenotypic drift in culture that can require a specific sub-clone of 444 hinder transferability between laboratories. . the MCF-7 445 Deleted: and which can 446 Overall, these data do not indicate that ELF electric and/or magnetic fields affect the transform and therefore may 447 neuroendocrine system in a way that would have an adverse impact on human health and the evidence is lose its responsiveness. In view 448 thus considered very weak. of these limitations, the significance of these results for human health remains questionable Deleted: open

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449 450 451 References 452

453 AFZAL S.M.J., LEVINE G.A. & LIBURDY R.P. (1998) Environmental-level magnetic fields and 454 estrogen-induced growth promotion in human breast and brain tumor cell lines. In: Electricity and 455 Magnetism in Biology and Medicine (ed. Bersani F), pp. 473-76. Bologna: Plenum Press.

456 AGNIR (2001) ELF electromagnetic fields and the risk of cancer. Report of an Advisory Group on Non- 457 ionising Radiation. Docs NRPB Vol. 2, No.1. Chilton: Oxon: National Radiological Protection Board.

458 AGNIR (2006) Power Frequency Electromagnetic Fields, Melatonin and the Risk of Breast Cancer. Report 459 of an Independent Advisory Group on Non-ionising Radiation, Documents of the Health Protection 460 Agency, Series B: Radiation, Chemical and Environmental Hazards, RCE-1. Chilton, UK: Health 461 Protection Agency.

462 AKERSTEDT T., ARNETZ B., FICCA G., PAULSSON L.E. & KALLNER A. (1999) A 50-Hz 463 electromagnetic field impairs sleep. J Sleep Res, 8(1): 77-81.

464 ARNETZ B.B. & BERG M. (1996) Melatonin and adrenocorticotropic hormon levels in video display unit 465 workers during work and leisure. J Occup Environ Med, 38(11): 1108-1110.

466 BAKOS J., NAGY N., THURÌCZY G. & SZABÌ L.D. (1997) Urinary 6-sulphatoxymelatonin excretion 467 is increased in rats after 24 hours of exposure to vertical 50 Hz, 100 µT magnetic field. 468 Bioelectromagnetics, 18(2): 190-192.

469 BAKOS J., NAGY N., THURÌCZY G. & SZABÌ L.D. (1999) Urinary 6-sulphatoxymelatonin excretion 470 of rats is not changed by 24 hours of exposure to a horizontal 50-Hz, 100-µT magnetic field. Electro 471 Magnetobiol, 18(1): 23-31.

472 BAKOS J., NAGY N., THURÔCZY G. & SZABÖ L.D. (1995) Sinusodial 50 Hz, 500 µT magnetic field 473 has no acute effect on urinary 6-sulphatoxymelatonin in W istar rats. Bioelectromagnetics, 16 377-380.

474 BLACKMAN C.F., BENANE S.G. & HOUSE D.E. (2001) The influence of 1.2 microT, 60 Hz magnetic 475 fields on melatonin- and tamoxifen-induced inhibition of MCF-7 cell growth. Bioelectromagnetics, 22(2): 476 122-128.

477 BRENDEL H., NIEHAUS M. & LERCHL A. (2000) Direct suppressive effects of weak magnetic fields 478 (50 Hz and 162/3 Hz) on melatonin synthesis i the pineal gland of Djungarian hamsters (Phodopus 479 sungorus). J Pineal Res, 29(4): 228-233.

480 BURCH J.B., REIF J.S., NOONAN C.W ., ICHINOSE T., BACHAND A.M., KOLEBER T.L. & YOST 481 M.G. (2002) Melatonin metabolite excretion among cellular telephone users. Int J Radiat Biol, 78(11): 482 1029-1036.

483 BURCH J.B., REIF J.S., NOONAN C.W . & YOST M.G. (2000) Melatonin metabolite levels in workers 484 exposed to 60-Hz magnetic fields: work in substations and with 3-phase conductors. J Occup Environ Med, 485 42(2): 136-142.

486 BURCH J.B., REIF J.S. & YOST M.G. (1999) Geomagnetic disturbances are associated with reduced 487 nocturnal excretion of a melatonin metabolite in humans. Neurosci Lett, 266 209-212 (1999a).

488 BURCH J.B., REIF J.S., YOST M.G., KEEFE T.J. & PITRAT C.A. (1998) Nocturnal excretion of a 489 urinary melatonin metabolite among electric utility workers. Scand J W ork Environ Health, 24(3): 183-189.

- 19 -

490 BURCH J.B., REIF J.S., YOST M.G., KEEFE T.J. & PITRAT C.A. (1999) Reduced excretion of a 491 melatonin metabolite in workers exposed to 60 Hz magnetic fields. Am J Epidemiol, 150(1): 27-36 (1999b).

492 BURCHARD J.F., NGUYEN D.H., MONARDES H.G. & PETITCLERC D. (2004) Lack of effect of 10 493 kV/m 60 Hz electric field exposure on pregnant dairy heifer hormones. Bioelectromagnetics, 25(4): 308- 494 312.

495 BURCHARD J.F., NGUYEN D.H., RICHARD L. & BLOCK E. (1996) Biological effects of electric and 496 magnetic fields on productivity of dairy cows. J Dairy Sci, 79(9): 1549-1554.

497 CHACON L. (2000) 50-Hz sinusoidal magnetic field effect on in vitro pineal N-acetyltransferase activity. 498 Electro Magnetobiol, 19 339-343.

499 CRASSON M., BECKERS V., PEQUEUX C., CLAUSTRAT B. & LEGROS J.J. (2001) Daytime 50 Hz 500 magnetic field exposure and plasma melatonin and urinary 6-sulfatoxymelatonin concentration profiles in 501 humans. J Pineal Res, 31(3): 234-241.

502 DAVIS S., KAUNE W .T., MIRICK D.K., CHEN C. & STEVENS R.G. (2001) Residential magnetic fields, 503 light-at-night, and nocturnal urinary 6-sulfatoxymelatonin concentration in women. Am J Epidemiol, 504 154(7): 591-600.

505 DE BRUYN L. & DE JAGER L. (1994) Electric Field Exposure and Evidence of Stress in Mice. Environ 506 Res, 65 149-160.

507 FREE M.J., KAUNE W .T., PHILLIPS R.D. & CHENG H.C. (1981) Endocrinological effects of strong 60- 508 Hz electric fields on rats. Bioelectromagnetics, 2(2): 105-121.

509 GAMBERALE F., OLSON B.A., ENEROTH P., LINDH T. & W ENNBERG A. (1989) Acute effects of 510 ELF electromagnetic fields: a field study of linesmen working with 400 kV power lines. Br J Ind Med, 46 511 729-737.

512 GRAHAM C., COOK M.R., GERKOVICH M.M. & SASTRE A. (2001) Examination of the melatonin 513 hypothesis in women exposed at night to EMF or bright light. Environ Health Perspect, 109(5): 501-507.

514 GRAHAM C., COOK M.R., GERKOVICH M.M. & SASTRE A. (2001) Melatonin and 6-OHMS in high- 515 intensity magnetic fields. J Pineal Res, 31(1): 85-88.

516 GRAHAM C., COOK M.R. & RIFFLE D.W . (1997) Human melatonin during continuous magnetic field 517 exposure. Bioelectromagnetics, 18(2): 166-171.

518 GRAHAM C., COOK M.R., RIFFLE D.W ., GERKOVICH M.M. & COHEN H.D. (1996) Nocturnal 519 melatonin levels in human volunteers exposed to intermittent 60 Hz magnetic-fields. Bioelectromagnetics, 520 17(4): 263-273.

521 GRAHAM C., COOK M.R., SASTRE A., RIFFLE D.W . & GERKOVICH M.M. (2000) Multi-night 522 exposure to 60 Hz magnetic fields: effects on melatonin and its enzymatic metabolite. Journal of Pineal 523 Research, 28 1-8.

524 GRAHAM C., SASTRE A., COOK M.R. & GERKOVICH M.M. (2001) All-night exposure to EMF does 525 not alter urinary melatonin, 6-OHMS or immune measures in older men and women. J Pineal Res, 31(2): 526 109-113.

527 GRIEFAHN B., KUNEMUND C., BLASZKEW ICZ M., GOLKA K. & DEGEN G. (2002) Experiments 528 on effects of an intermittent 16.7-Hz magnetic field on salivary melatonin concentrations, rectal 529 temperature, and heart rate in humans. Int Arch Occup Environ Health, 75(3): 171-178.

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530 GRIEFAHN B., KUNEMUND C., BLASZKEW ICZ M., GOLKA K., MEHNERT P. & DEGEN G. (2001) 531 Experiments on the effects of a continuous 16.7 Hz magnetic field on melatonin secretion, core body 532 temperature, and heart rates in humans. Bioelectromagnetics, 22(8): 581-588.

533 GROTA L.J., REITER R.J., KENG P. & MICHAELSON S. (1994) Electric-field exposure alters serum 534 melatonin but not pineal melatonin synthesis in male-rats. Bioelectromagnetics, 15(5): 427-437.

535 HACKMAN R.M. & GRAVES H.B. (1981) Corticosterone levels in mice exposed to high-intensity 536 electric fields. Behav Neural Biol, 32(2): 201-213.

537 HARLAND J.D., LEVINE G.A. & LIBURDY R.P. (1998) Differential inhibition of tamoxifen's oncostatic 538 functions in a human breast cancer cell line by a 12 mG (1.2 mT) magnetic field. In: Electricity and 539 Magnetism in Biology and Medicine (ed. Bersani, F.), pp. 465-468. Bologna: Plenum Press.

540 HARLAND J.D. & LIBURDY R.P. (1997) Environmental magnetic fields inhibit the antiproliferative 541 action of tamoxifen and melatonin in a human breast cancer cell line. Bioelectromagnetics, 18(8): 555-562.

542 HONG S.C., KUROKAW A Y., KABUTO M. & OHTSUKA R. (2001) Chronic exposure to ELF magnetic 543 fields during night sleep with electric sheets: effects on diurnal melatonin rhythms in men. 544 Bioelectromagnetics, 22(2): 138-143.

545 INTERNATIONAL AGENCY FOR RESEARCH ON CANCER I. (2002) Monographs on the evaluation 546 of carcinogenic risks to humans. Vol.80 Non-ionizing radiation Part 1: Static and extremely low-frequency 547 (ELF) electric and magnetic fields. Lyon: IARC.

548 INTERNATIONAL COMMISSION ON NON-IONIZING RADIATION PROTECTION (2003) Exposure 549 to static and low frequency electromagnetic fields, biological effects and health consequences (0-100 kHz). 550 Munich, Germany: ICNIRP.

551 ISHIDO M. (2001) Magnetic fields (MF) of 50 Hz at 1.2 µT as well as 100 µT cause uncoupling of 552 inhibitory pathways of adenylyl cyclase mediated by melatonin a1 receptor in MF-sensitive MCF-7 cells. 553 Carcinogenesis, 22(7): 1043-1048.

554 JOHN T.M., LIU G.-Y. & BROW N G.M. (1998) 60 Hz magnetic field exposure and urinary 6- 555 Sulphatoxymelatonin levels in rats. Bioelectromagnetics, 19(3): 172-180.

556 JUUTILAINEN J., STEVENS R.G., ANDERSON L.E., HANSEN N.H., KILPELAINEN M., KUMLIN T., 557 LAITINEN J.T., SOBEL E. & W ILSON B.W . (2000) Nocturnal 6-hydroxymelatonin sulfate excretion in 558 female workers exposed to magnetic fields. J Pineal Res, 28(2): 97-104.

559 KARASEK M. & LERCHL A. (2002) Melatonin and magnetic fields. Neuro Endocrinol Lett, 23(Suppl 1): 560 84-87.

561 KATO M., HONMA K., SHIGEMITSU T. & SHIGA Y. (1994) Circularly polarized, sinusoidal, 50 Hz 562 magnetic field exposure does not influence plasma testosterone levels of rats. Bioelectromagnetics, 15 513- 563 518.

564 KATO M., HONMA K., SHIGEMITSU T. & SHIGA Y. (1994) Circularly polarized 50-Hz magnetic field 565 exposure reduces pineal gland and blood melatonin concentrations of Long-Evans rats. Neurosci Lett, 166 566 59-62.

567 KATO M., HONMA K., SHIGEMITSU T. & SHIGA Y. (1994) Horizontal or vertical 50-Hz, 1-micro T 568 magnetic fields have no effect on pineal gland or plasma melatonin concentration of albino rats. Neurosci 569 Lett, 168 205-208.

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570 KATO M., HONMA K., SHIGEMITSU T. & SHIGA Y. (1993) Effects of exposure to a circularly 571 polarized 50-Hz magnetic field on plasma and pineal melatonin levels in rats. Bioelectromagnetics, 14 572 1997-106.

573 KATO M., HONMA K.-I., SHIGEMITSU T. & SHIGA Y. (1994) Recovery of nocturnal melatonin 574 concentration takes place within one week following cessation of 50 Hz circulary polarized magnetic field 575 exposure for six weeks. Bioelectromagnetics, 15 489-492.

576 KATO M. & SHIGEMITSU T. (1997) Effects of 50 Hz magnetic fields on pineal function in the rat, in The 577 Melatonin Hypothesis, Breast cancer and use of electric power., pp. 337-376. Battelle Press.

578 KUROKAW A Y., NITTA H., IMAI H. & KABUTO M. (2003) Acute exposure to 50 Hz magnetic fields 579 with harmonics and transient components: lack of effects on nighttime hormonal secretion in men. 580 Bioelectromagnetics, 24(1): 12-20.

581 LEE J.M., JR., STORMSHAK F., THOMPSON J.M., HESS D.L. & FOSTER D.L. (1995) Melatonin and 582 puberty in female lambs exposed to EMF: a replicate study. Bioelectromagnetics, 16(2): 119-123.

583 LEE J.M., STORMSHAK F., THOMPSON J.M., THINESEN P., PAINTER L.J., OLENCHEK E.G., 584 HESS D.L., FORBES R. & FOSTER D.L. (1993) Melatonin secretion and puberty in female lambs 585 exposed to environmental electric and magnetic-fields. Biol Reprod, 49(4): 857-864.

586 LEMAN E.S., SISKEN B.F., ZIMMER S. & ANDERSON K.W . (2001) Studies of the interactions 587 between melatonin and 2 Hz, 0.3 mT PEMF on the proliferation and invasion of human breast cancer cells. 588 Bioelectromagnetics, 22(3): 178-184.

589 LERCHL A., REITER R.J., HOW ES- KA, NONAKA K.O. & STOKKAN K.A. (1991) Evidence that 590 extremely low-frequency Ca2+ cyclotron resonance depresses pineal melatonin synthesis in vitro. Neurosci 591 Lett, 124(2): 213-215.

592 LEVALLOIS P., DUMONT M., TOUITOU Y., GINGRAS S., MASSE B., GAUVIN D., KROGER E., 593 BOURDAGES M. & DOUVILLE P. (2001) Effects of electric and magnetic fields from high-power lines 594 on female urinary excretion of 6-sulfatoxymelatonin. Am J Epidemiol, 154(7): 601-609.

595 LEW Y H., MASSOT O. & TOUITOU Y. (2003) Magnetic field (50 Hz) increases N-acetyltransferase, 596 hydroxy-indole-O-methyltransferase activity and melatonin release through an indirect pathway. Int J 597 Radiat Biol, 79(6): 431-435.

598 LIBURDY R.P., SLOMA T.R., SOKOLIC R. & YASW EN P. (1993) ELF magnetic fields, breast cancer, 599 and melatonin: 60 Hz fields block melatonin's oncostatic action on ER+ breast cancer cell proliferation. J 600 Pineal Res, 14 89-1997.

601 LONNE R.S., ANDERSSON B., MELIN L., SCHULTZBERG M., ARNETZ B. & BERG M. (2000) 602 Provocation with stress and electricity of patients with "sensitivity to electricity". J Occup Environ Med, 603 42(5): 512-516.

604 LÖSCHER W ., MEVISSEN M. & LERCHL A. (1998) Exposure of female rats to a 100-microT 50 Hz 605 magnetic field does not induce consistent changes in nocturnal levels of melatonin. Radiat Res, 150(5): 606 557-567.

607

608 MARESH C.M., COOK M.R., COHEN H.D., GRAHAM C. & GUNN W .S. (1988) Exercise testing in the 609 evaluation of human responses to powerline frequency fields. Aviat Space Environ Med, 59(12): 1139- 610 1145.

- 22 -

611 MARGONATO V., VEICSTEINAS A., CONTI R., NICOLINI P. & CERRETELLI P. (1993) Biologic 612 effects of prolonged exposure to ELF electromagnetic-fields in rats. I. 50 Hz electric-fields. 613 Bioelectromagnetics, 14(5): 479-493.

614 MARTINEZ S.F., GIMENEZ G.M., ARMANAZAS E. & RUIZ T.A. (1992) Pineal 'synaptic ribbons' and 615 serum melatonin levels in the rat following the pulse action of 52-Gs (50-Hz) magnetic fields: an evolutive 616 analysis over 21 days. Acta Anat (Basel), 143(4): 289-293.

617 MCKINLAY, A. F., ALLEN, S. G., COX, R., DIMBYLOW , P. J., MANN, S. M., MUIRHEAD, C. R., 618 SAUNDERS, R. D., SIENKIEW ICZ, Z. J, STATHER, J. W ., and W AINW RIGHT, P. J. (2004) Review of 619 the Scientific Evidence for limiting exposure to electromagnetic fields (0-300 GHz). NRPB (15 (3)).

620 MEVISSEN M., LERCHL A. & LÖSCHER W . (1996) Study on pineal function and DMBA-induced 621 breast-cancer formation in rats during exposure to a 100-mg, 50-Hz magnetic-field. J Toxicol Environ 622 Health, 48(2): 169-185.

623

624 NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH AND SCIENCES, NIEHS (1998) 625 Assessment of health effects from exposure to power-line frequency electric and magnetic fields. National 626 Institute of Environmental Health Sciences W orking Group Report. Research Triangle Park, NC: National 627 Institute of Health (NIH Publication No 98-3981).

628 NIEHAUS M., BRÜGGEMEYER H., BEHRE H.M. & LERCHL A. (1997) Growth retardation, testicular 629 stimulation, and increased melatonin synthesis by weak magnetic fields (50Hz) in Djhungarian hamsters, 630 Phodopus sungorus. Biochem Biophysi Res Commun, 234 707-711.

631 PFLUGER D.H. & MINDER C.E. (1996) Effects of exposure to 16.7 Hz magnetic fields on urinary 6- 632 hydroxymelatonin sulfate excretion of swiss railway workers. J Pineal Res, 21(2): 91-100.

633 PICAZO M.L., CATALÊ M.D., ROMO M.A. & BARDASANO J.L. (1998) Inhibition of melatonin in the 634 plasma of third-generation male mice under the action of elf magnetic fields. Electro Magnetobiol, 17(1): 635 75-85.

636 PICAZO M.L., DE MIGUEL M.P., ROMO M.A., VARELA L., FRANCO P., GIANONATTI C. & 637 BARDASANO J.L. (1996) Changes in mouse adrenal gland functionality under second-generation chronic 638 exposure to ELF magnetic fields: I. Males. Electro Magnetobiol, 15(2): 85-98.

639 PORTET R. & CABANES J. (1988) Development of young rats and rabbits exposed to a strong electric 640 field. Bioelectromagnetics, 9 95-104.

641 QUINLAN W .J., PETRONDAS D., LEBDA N., PETTIT S. & MICHALESON S.M. (1985) 642 Neuroendocrine parameters in the rat exposed to 60-Hz electric fields. Bioelectromagnetics, 6 381-389.

643 REITER RJ (1997) Melatonin biosynthesis, regulation, and effects. In: The Melatonin Hypothesis: Breast 644 Cancer and the Use of Electric Power (eds. Stevens RG, W ilson BW & Anderson LE), pp. 25-48. 645 Columbus, Ohio: Battelle Press.

646 REITER R.J., ANDERSON L.E., BUSCHBOM R.L. & W ILSON B.W . (1988) Reduction of the nocturnal 647 rise in pineal melatonin levels in rats exposed to 60-Hz electric fields in utero and for 23 days after birth. 648 Life Sci, 42(22): 2203-2206.

649 ROGERS W .R., REITER R.J., BARLOW W .L., SMITH H.D. & ORR J.L. (1995) Regularly scheduled, 650 day-time, slow-onset 60 Hz electric and magnetic field exposure does not depress serum melatonin 651 concentration in nonhuman primates. Bioelectromagnetics, Suppl(3): 111-118.

- 23 -

652 ROGERS W .R., REITER R.J., SMITH H.D. & BARLOW W .L. (1995) Rapid-onset/offset, variably 653 scheduled 60 Hz electric and magnetic field exposure reduces nocturnal serum melatonin concentration in 654 nonhuman primates. Bioelectromagnetics, Suppl(3): 119-122.

655 ROSEN L.A., BARBER I. & LYLE D.B. (1998) A 0.5 G, 60 Hz magnetic field suppresses melatonin 656 production in pinealocytes. Bioelectromagnetics, 19(2): 123-127.

657 SASSER, L. B., MORRIS, J. E., BUSCHBOM, R. L., MILLER, D. L., and ANDERSON, L. E. (1991) 658 Effect of 60 Hz electric fields on pineal melatonin during various times of the dark period. In Project 659 Resumes, DOE Annual Review of Research on Biological Effects of 50 and 60 Hz Electric and Magnetic 660 Fields. November 1991, Milwaukee, W isconsin, pA-24.

661 SELMAOUI B., LAMBROZO J. & TONITON Y. (1997) Endocrine function in young men exposed for 662 one night to a 50-Hz magnetic field. A circadian study of pituitary, thyroid and adrenocortical hormones. 663 Life Sci, 61(5): 473-486.

664 SELMAOUI B., LAMBROZO J. & TOUITOU Y. (1996) Magnetic-fields and pineal function in humans - 665 Evaluation of nocturnal acute exposure to extremely-low-frequency magnetic-fields on serum melatonin 666 and urinary 6-sulfatoxymelatonin circadian-rhythms. Life Sci, 58(18): 1539-1549.

667 SELMAOUI B. & TOUITOU Y. (1999) Age-related differences in serum melatonin and pineal NAT 668 activity and in the response of rat pineal to a 50-Hz magnetic field. Life Sci, 64(24): 2291-2297.

669 SELMAOUI B. & TOUITOU Y. (1995) Sinusoidal 50-Hz magnetic fields depress rat pineal NAT activity 670 and serum melatonin. Role of duration and intensity of exposure. Life Sci, 57(14): 1351-1358.

671 SHAH P.N., MHATRE M.C. & KOTHARI L.S. (1984) Effect of melatonin on mammary carcinogenesis in 672 intact and pinealectomized rats in varying photoperiods. Cancer Res, 44(8): 3403-3407.

673 STEVENS R.G. (1987) Electric power use and breast cancer: A hypothesis. Am J Epidemiol, 125(4).

674 TAMARKIN L., COHEN M., ROSELLE D., REICHERT C., LIPPMAN M. & CHABNER B. (1981) 675 Melatonin inhibition and pinealectomy enhancement of 7,12-dimethlbanz(a)anthracene-induced mammary 676 tumors in the rat. Cancer Res, 41 4432-4436.

677 THOMPSON J.M., STORMSHAK F., LEE J.M., HESS D.L. & PAINTER L. (1995) Cortisol secretion and 678 growth in ewe lambs chronically exposed to electric and magnetic fields of a 60-Hertz 500-kV AC 679 transmission line. J Anim Sci, 73(11): 3274-3280.

680 TOUITOU Y., LAMBROZO J., CAMUS F. & CHARBUY H. (2003) Magnetic fields and the melatonin 681 hypothesis: a study of workers chronically exposed to 50-Hz magnetic fields. Am J Physiol Regul Integr 682 Comp Physiol, 284(6): R1529-R1535.

683 TRIPP H.M., W ARMAN G.R. & ARENDT J. (2003) Circularly polarised MF (500 micro T 50 Hz) does 684 not acutely suppress melatonin secretion from cultured W istar rat pineal glands. Bioelectromagnetics, 24(2): 685 118-124.

686 TRUONG H., SMITH C. & YELLON S.M. (1996) Photoperiod control of the melatonin rhythm and 687 reproductive maturation in the juvenile djungarian hamster: 60-Hz magnetic field exposure effects. Biol 688 Reprod, 55(2): 455-460.

689 TRUONG H. & YELLON S.M. (1997) Effect of various acute 60 Hz magnetic field exposures on the 690 nocturnal melatonin rise in the adult Djungarian hamster. J Pineal Res, 22(4): 177-183.

- 24 -

691 W ARMAN G.R., TRIPP H., W ARMAN V.L. & ARENDT J. (2003) Acute exposure to circularly polarized 692 50-Hz magnetic fields of 200-300 microT does not affect the pattern of melatonin secretion in young men. J 693 Clin Endocrinol Metab, 88(12): 5668-5673.

694 W ARMAN G.R., TRIPP H.M., W ARMAN V.L. & ARENDT J. (2003) Circadian neuroendocrine 695 physiology and electromagnetic field studies: precautions and complexities. Radiat Prot Dosimetry, 106(4): 696 369-373.

697 W ILSON B.W ., ANDERSON L.E., HILTON D.I., PHILLIPS & RD (1981) Chronic exposure to 60 Hz 698 electric fields: effects on pineal function in the rat. Bioelectromagnetics, 7 239-242.

699 W ILSON B.W ., ANDERSON L.E., HILTON D.I. & PHILLIPS R.D. (1983) Erratum. Chronic exposure to 700 60 Hz electric fields: Effects on pineal function in the rat. Bioelectromagnetics, 4 293.

701 W ILSON B.W ., CHESS E.K. & ANDERSON L.E. (1986) 60-Hz Electric-Field Effects on Pineal 702 Melatonin Rhythms: Time Course for Onset and Recovery. Bioelectromagnetics, 7 239-242.

703 W ILSON B.W ., MATT K.S., MORRIS J.E., SASSER L.B., MILLER D.L. & ANDERSON L.E. (1999) 704 Effects of 60 Hz magnetic field exposure on the pineal and hypothalamic-pituitary-gonadal axis in the 705 Siberian hamster (Phodopus sungorus). Bioelectromagnetics, 20(4): 224-232.

706 W ILSON B.W ., W RIGHT C.W ., MORRIS J.E., BUSCHBOM R.L., BROW N D.P., MILLER D.L., 707 SOMMERS-FLANNIGAN R. & ANDERSON L.E. (1990) Evidence for an effect of ELF electromagnetic 708 fields on human pineal gland function. J Pineal Res, 9 259-269.

709 W OOD A.W ., ARMSTRONG S.M., SAIT M.L., DEVINE L. & MARTIN M.J. (1998) Changes in human 710 plasma melatonin profiles in response to 50 -Hz magnetic field exposure. J Pineal Res, 25(2): 116-127.

711 YELLON S.M. (1994) Acute 60 Hz magnetic field exposure effects on the melatonin rhytm in the pineal 712 gland and circulation of the Djungarian Hamster. J Pineal Res, 16 136-144.

713 YELLON S.M. (1996) 60-Hz magnetic field exposure effects on the melatonin fhythm and photoperiod 714 control of reproduction. Am J Physiol, 270(5 Pt 1): E816-E821.

715 YELLON S.M. & TRUONG H.N. (1998) Melatonin rhythm onset in the adult Siberian hamster: influence 716 of photoperiod but not 60-Hz magnetic field exposure on melatonin content in the Pineal gland and in 717 circulation. J Biol Rhythms, 13(1): 52-59.

718 YOUNGSTEDT S.D., KRIPKE D.F., ELLIOTT J.A. & ASSMUS J.D. (2002) No association of 6- 719 sulfatoxymelatonin with in-bed 60-Hz magnetic field exposure or illumination level among older adults. 720 Environ Res, 89(3): 201-209. 721 722

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