Appendix A
Tables



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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Appendix A Tables

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields TABLE A3-1 In Vitro Assays of Electric-and Magnetic-Field Exposure and Genotoxicity Study Cell Type Exposure Characteristics Electric-Field Strength of Culture Media End Points Evaluated Outcome Hungate et al. 1979 Salmonella TA100 or TA98 exposed 20 hr in liquid nutrient broth suspension 200-800 kV/m electric field in air Cannot be determined from report Mutation 1.5-3-fold increase in mutation frequency in TA100 at 800,000 V/m Moore 1979 Salmonella TA98 and TA100 tester strains exposed during growth in nutrient broth for 5-24 hr 0.3-Hz triangular magnetic field at 0.015 and 0.03 T Induced electric field cannot reliably be estimated from report Reverent assay No significant effects observed Wolff et al. 1980 CHO cells exposed 4 hr (SCEs) or 13 hr (chromosomal aberration) NMR gradient field; 1.82 pulses/sec, 4.6 T/sec; coexposed 0.352-T static magnetic field and 5-mW/cm2 magnetic field at 15 MHz Cannot be determined from report Chromosomal aberrations and SCEs No significant effects observed Wolff et al. 1980 CHO cells exposed 4 hr (SCEs) or 13 hr, 40 min (chromosomal aberration) 0.35 T plus coexposure to RF field at 15 MHz, 5 mW/cm2 and time-varying magnetic-field changes at 4.6 T/sec and 1.82 T/sec 0 Chromosomal aberrations and SCEs No significant effects observed Cooke and Morris 1981 Human lymphocytes exposed 1 hr 0.5-1.0 T 0 Chromosomal aberrations and SCEs No significant effects observed

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Thomas and Morris 1981 E. coli AB1157 exposed 5 hr (agar plates) 1.0 R ± coexposure to RF field at 1 mW/cm2 and gradient magnetic field at 1-12 T/sec Not calculated Revertant assay No significant effects observed Thomas and Morris 1981 recA, uvrA, or recA urvA E. coli: exposed 5 hr in Petri dishes 1.0 T 0 Survival (recA, uvrA, or recA uvrA E. coli mutants) compared with wild type No significant effects observed Thomas and Morris 1981 E. coli recA, uvrA, and recA uvrA mutants or E. coli AB 1157 exposed 40 min or 5 hr on agar Petri plates Gradient magnetic field at 1-12 T/sec; coexposure to 0.094-T static magnetic field and 1-mW/cm2 RF field 2-30 mV/m calculated from exposure apparatus by McCann et al. (1993) Revertant assay No significant effects observed Mileva 1982 Human peripheral lymphocytes: exposed 15-360 min 0.3 T 0 Chromosomal aberrations No significant effects observed Nordenson et al. 1984 Human peripheral lymphocytes exposed 3 hr to phytohemagglutinin stimulation 50-Hz sinusoidal field applied through agarose bridges 14 V/m (10 A/m2) calculated from exposure apparatus by McCann et al. (1993) Chromosomal aberrations No significant effects observed Nordenson et al. 1984 Human peripheral lymphocytes in whole blood exposed 1 min before phytohemagglutinin stimulation 10 spark discharge pulses, 2 msec wide 250-350 kV/m Chromosomal aberrations At the highest dose, a significant increase in chromosomal breaks

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Study Cell Type Exposure Characteristics Electric-Field Strength of Culture Media End Points Evaluated Outcome d'Ambrosia et al. 1985 Bovine lymphocytes in liquid culture medium exposed 72 hr by applying external electrodes to side walls of culture flasks 50-Hz sinusoidal field with 11% THD applied through capacitative coupling 0.016 V/m (0.024 A/m2) Chromosomal aberrations A significant increase (& sim;3-fold) in chromosomal aberrations for three experiments Cohen 1986; Cohen et al. 1986a,b Peripheral blood lymphocytes from normal individuals (Cohen et al. 1986b) and individuals with chromosomal instability syndromes exposed 69-hr culture period 60-Hz sinusoidal field applied through agarose bridges and coexposure to 60-Hz sinusoidal magnetic field at 10-200 µT (38-75 mT/sec) 0.24 V/m (0.2 A/m2) (no reliable estimate available from published report) Chromosomal aberrations and SCEs No significant effects observed Cohen et al. 1986a,b Peripheral blood lymphocytes normal (Cohen et al. 1986b) and with chromosomal instability exposed 69 hr in culture 60-Hz sinusoidal field, circularly polarized, at 10-200 µT (38-75 mT/sec) 0.7-13 mV/m calculated from exposure apparatus by McCann et al. (1993); coexposure to 60-Hz sinusoidal electric field, 0.24 V/m (0.3 A/m2) (McCann et al. 1993) Chromosomal aberrations and SCEs No significant effects observed

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Juutilainen and Liimatainen 1986 Salmonella TA100 and TA98 exposed in top agar or liquid nutrient broth culture for 48 or 6.5 hr, respectively 100-Hz sinusoidal field at 0.13, 1.3, 13, and 130 µT 0.2, 2.0, 20, and 200 µV/m (Petri dishes); and 1.5, 15, 150, and 1,500 µV/m (flasks) calculated from exposure apparatus by McCann et al. (1993) Revertant assay No significant effects observed Livingston et al. 1986, 1991 Human lymphocytes or CHO cells exposed 24-96 hr or 72 hr, respectively 60-Hz sinusoidal field applied through agarose bridges 0.024-24 V/m (no reliable estimate available from published report) (0.03-30 A/m2) Chromosomal aberrations No significant effects observed Livingston et al. 1986, 1991 Peripheral blood lymphocytes or CHO cells exposed 24-96 hr or 72 hr, respectively 60-Hz sinusoidal field, circularly polarized, at 0.22 mT (0.082 T/sec) 0.7-13 mV/m calculated from exposure apparatus by McCann et al. 1993; coexposure to 60-Hz sinusoidal electric field at 0.024-24 V/m SCEs and micronuclei No significant effects observed Whitson et al. 1986 Normal human fibroblasts previously or post irradiated with UV light (254 nm) exposed up to 48 hr 60-Hz applied through capacitative coupling; field in air outside media 10 kV/m 0.4 mV/m DNA single-strand breaks assayed via 5-bromodeoxyuridine photolysis; pyrimidine dimers assayed using hydrolysis then two-dimensional paper chromatography, or No significant effects observed

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Study Cell Type Exposure Characteristics Electric-Field Strength of Culture Media End Points Evaluated Outcome         by treating cells with a UV-specific endonuclease followed by a fragment sizing analysis on sucrose gradients   Takahashi et al. 1987 Chinese hamster V79 cells exposed 24 hr 100-Hz saw-toothed field at 0.180-2.500 mT (7.2-100 T/sec) 0.02-0.33 V/m calculated from exposure apparatus by McCann et al. (1993) SCEs No significant effects observed d'Ambrosia et al. 1988-1989 Bovine lymphocyte cultures exposed 3 or 45 hr 50-Hz sinusoidal field applied through agarose bridges 0.77-7.7 V/m (1-10 A/m2) Chromosomal aberrations Significant increases in chromatid breaks at high exposure level reported after 45-hr exposure and in total aberrations in one of two cultures tested after 3-hr exposure Reese et al. 1988 CHO cells exposed 1 hr 60-Hz sinusoidal field applied through agarose bridges; coexposure to 60-Hz sinusoidal field at 0-2 mT 1-38 V/m DNA single-strand breaks No significant effects reported

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Reese et al. 1988 CHO cells exposed 1 hr 60-Hz sinusoidal field at 2 mT (0.75 T/sec); coexposed to 60-Hz sinusoidal electric field at 0-38 V/m 8 mV/m calculated by McCann et al. (1993) DNA repair measured by alkaline elution No significant effects observed Bersani et al. 1989 Human peripheral lymphocytes or two human cell lines were exposed 48 hr 50-Hz saw-toothed field at 2.5 mT peak strength (1 T/sec; induced pulse 2-msec wide at 2 mV/m) 2 mV/m DNA single-strand breaks No significant effects observed Cossarizza et al. 1989; Bersani et al. 1989 Human lymphocytes exposed 6 hr after some cultures irradiated with 100-Gy 60Co 50-Hz saw-toothed field at 2.5 mT peak strength (1 T/sec; induced pulse 2-msec wide at 2 mV/m) 2 mV/m Unscheduled DNA synthesis No significant effects observed Peteiro-Cartelle and Cabezas-Cerrato 1989 Human lymphocytes exposed 3 hr or simultaneously cultured and exposed 72-96 hr 0.045-0.125 T 0 Chromosomal aberrations and SCEs No significant effects observed Rosenthal and Obe 1989 Human peripheral lymphocytes cultured 72 hr in magnetic field 50-Hz sinusoidal field at 0.1-7.5 mT (0.031-2.4 T/sec) 0.1-8 mV/m calculated from exposure apparatus by McCann et al. (1993) SCEs No significant effects observed Rosenthal and Obe 1989 Human peripheral lymphocytes pretreated with NMU, DEB, or trenimon and cultured up to 72 hr in presence of magnetic field 50-Hz sinusoidal field at 0.5-2 mT (0.16-0.63 T/sec) with coexposure to NMU or trenimon 0.61-2 mV/m SCEs Statistically significant (p < 0.05) increase in SCEs only in cells treated with NMU or trenimon

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Study Cell Type Exposure Characteristics Electric-Field Strength of Culture Media End Points Evaluated Outcome Takatsuji et al. 1989 Human peripheral lymphocytes exposed <30 min 1.1 T + coexposure to protons and alpha particles 0 Chromosomal aberrations Proton coexposure significant dose-response effect; frequency of dicentrics increased for both coexposures Frazier et al. 1990 Human peripheral lymphocytes previously exposed to γ-irradiation (5 Gy) exposed 0-30 min during repair 60-Hz sinusoidal fields applied through agarose bridges; coexposure to γ radiation, 60-Hz sinusoidal magnetic field at 0-0.001 T 1-20 V/m DNA single-strand breaks No significant effects reported Garcia-Sagredo et al. 1990 Peripheral blood lymphocytes or CHO cells exposed 24-96 hr or 72 hr, respectively 4.4-kHz saw-toothed pulses of 5 msec width, 14 pulses per sec at 1-4 mT peak strength (50-200 T/sec) 0.07-0.27 V/m calculated from exposure apparatus by McCann et al. (1993) SCEs No significant effects observed Balcer-Kubiczek and Harrison 1991 C3H/10T1/2 cells exposed 24 hr; post-exposure of some cells with TPA, either preceded or followed by X-rays given at 0.5, 1, or 1.5 Gy 2.45-GHz microwaves pulse modulated at 120 Hz with electric fields at 18, 56, or 120 V/m and magnetic fields at 0.09, 0.27, or 0.56 µT Not calculated Cell survival and neoplastic transformation EMF alone demonstrated no effect; transformation due to EMF plus TPA highly significant; neoplastic transformation dependent on level of EMF exposure and additive of X-rays given as a cocarcinogen

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields García-Sagredo and Monteagudo 1991 Human peripheral lymphocytes cultivated in vitro 72 hr and exposed over the last 24 hr to magnetic fields Quasi-rectangular pulses lasting 26 µsec, frequency 4.4 kHz, in trains of 5 msec at 14-Hz repetition rate with peak strength at 1, 2, and 4 mT Not calculated Chromosomal aberrations Significant effect observed at 4 mT; no significant effects observed at 1 and 2 mT Khalil and Qassem 1991 Human lymphocytes grown 24, 48, or 72 hr in presence of the magnetic field 50-Hz pulsed field at 1 mT (0.72 T/sec) 0.043 V/m Chromosomal aberrations Significant decreases in mitotic index; increases in chromosomal aberrations for all exposure periods; slight increase in SCEs (p < 0.05) only for 72 hr Novelli et al. 1991 Saccharomyces cerevisiae cultures exposed up to 24 hr and then examined by pulsed-field gel electrophoresis (PFGE) 50-Hz electric-and magnetic-field exposure consisting of 4 units: 1. uniform magnetic field; 2. uniform electric field; 3. orthogonal uniform electric and magnetic field; and 4. no field control with electric field from 0.1-20 kV/m and magnetic field from 0.2-200 µT Not calculated DNA double-strand breaks No significant effects observed

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Study Cell Type Exposure Characteristics Electric-Field Strength of Culture Media End Points Evaluated Outcome Scarfi et al. 1991 Human lymphocytes grown 72 hr in the magnetic field 50-Hz saw-toothed field at 0.025 T (some cell cultures coexposed to mitomycin C) 0.005 V/m Micronuclei No significant effects observed Fiorani et al. 1992 Cultured K562 human tumor cells exposed 1, 4, 6, 12, or 24 hr 50-Hz electric field at 0.2-20 kV/m and magnetic field at 0.2-200 µT Not calculated DNA single-strand breaks and cell growth No significant effects observed Chahal et al. 1993 E. coli K-12 strain AB1157, and its derivatives TK702 umuC (deficient in error prone repair) and TK501 umuC uvrB (lacking both error prone and excision repair) exposed 1 or 16 hr 1-Hz electric field at 3 kV/m for 1 hr or 1 kV/m for 16 hr alone or in combination with UV and/or mitomycin C Not calculated Mutations No significant effects observed Fiorio et al. 1993 Chinese hamster V79 cells exposed 10 days 50-Hz sinusoidal magnetic field at 200 µT Not calculated Chromosomal aberrations, SCEs, and cell survival No significant increase in chromosomal aberrations or SCEs; cell viability decreased by 50% after 10 days with only 100 plated; however, no reduction in viability with 2 × 105 seeded cells

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Scarfí et al. 1993 Human peripheral lymphocytes exposed 72 hr and assayed using the cytokinesis-block micronucleus assay 50-Hz ac sinusoidal electric field at 0.5, 2, 5, and 10 kV/m Not calculated Micronuclei No significant effects observed Zwingelberg et al. 1993 Cultured rat peripheral lymphocytes exposed 7-28 days, 24 hr/day Homogenous 50-Hz, magnetic field at 30 mT Not calculated SCEs and chromosomal aberrations No significant effects observed Fairbairn and O'Neill 1994 HL-60 cells, Raji cells, HeLa cells, and human peripheral lymphocytes exposed 2-30 min 50-Hz magnetic field with peak amplitude at 5 mT and pulse duration of 3 msec Not calculated DNA single-strand breaks No significant effect observed Libertin et al. 1994 HeLa cells transfected with a CAT construct transcriptionally driven by HIV-LTR promoter exposed 24 or 48 hr ac field: 10 Hz-1.6 kHz, 0.07-35 µT; dc field: 170 µT Not calculated HIV-LTR expression No significant effects observed Nordenson et al. 1994 Human amniotic cells exposed 72 hr continuously and intermittently (15 sec on, 15 sec off; 2 sec on, 20 sec off) 50-Hz magnetic field at 30 µT (rms) and 300 µT Not calculated Chromosomal aberrations A significant increase observed in intermittently exposed cells; no significant increase seen in continuously exposed cells

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields TABLE A5-7 Electric-and Magnetic-Field Exposure and Childhood Cancers Other than Leukemia and Brain Cancer: Results Study Exposure Category Number of Cases Number of Controls Crude ORa 95% CIb Potential Confounders Addressedc Wertheimer and Leeper 1979 Birth addresses:         Age of onset, sex,  socioeconomic status, urban residence, family pattern, traffic congestion   HCCd 17 9 2.4 0.9-6.1     LCCe 31 39         Death addresses:             HCC 18 17 1.1 0.5-2.4     LCC 45 46       Tomenius 1996 Total residences:         Age, sex, church district of birth   =0.3 µT 11 0         <0.3 µT 352 309       Savitz et al. 1988 Field measurements for low-power conditions:         Maternal age, father's education, family income, maternal smoking in pregnancy, traffic density, age, sex, geographic area of residence   >0.2 µT 1 16 0.3 0.4-2.1     <0.2 µT 39 191         Field measurements for high-power conditions:             >0.2 µT 3 29 0.5 0.1-1.7     <0.2 µT 37 175         Two-level wire codes:             High 28 52 1.5 0.9-2.6     Low 74 207         Wire codes:             Very high 4 8 1.6 0.5-5.8     Very low 27 88      

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Study Exposure Cases Observed Cases Expectedf Crude ORa 95% CIb Potential Confounders Addressedc Verkasalo et al. 1993 ≥ 0.2 µT 3 2.42 1.2 0.3-3.6 Age, sex   0.01-0.19 48 44.7 1.1 0.8-1.4     ≥0.4 µT-yr 4   1.0 0.3-2.6     0.01-0.39 47   1.1 0.8-1.4   a Odds ratio calculated without consideration of possible confounders (ratio of exposed to unexposed cases divided by the ratio of exposed to unexposed controls). b 95% confidence interval for the odds ratio calculated without consideration of possible confounders. c Includes all factors considered to be potential confounders whether or not statistical adjustments were made for them. d HCC, high current configuration. e LCC, low current configuration. f Cases expected on the basis of incidence data for the disease in the general population.

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields TABLE A5-8 Residential Electric-and Magnetic-Field Exposure and All Childhood Cancers: Results Study Exposure Category Number of Cases Number of Controls Crude ORa 95% CIb Adjusted ORc Potential Confounders Addressedd Wertheimer  and Leeper 1979 Birth address:           Age of onset, sex, traffic congestion, socioeconomic status (SES), urban residence, family pattern   HCCe 101 55 2.3 1.6-3.4       LCCf 171 217           Death address:               HCC 129 74 2.2 1.6-3.1       LCC 199 254         Tomenius 1986 Total residences:           Age, sex, church district of birth, permanent vs. transient residence   ≥0.3 µT 34 14 2.1 1.1-4.0       <0.3 µT 1,095 955         Savitz et al. 1988 Field measurements for low-power conditions:           Maternal age, father's education, family income, maternal smoking in pregnancy, traffic density, age, sex, geographic area of residence   >0.2 µT 13 16 1.4 0.6-2.9 (1.2-1.5)     <0.2 µT 115 191           Field measurements for high-power conditions:               >0.2 µT 19 29 1.0 0.6-2.0       <0.2 µT 110 175           Two-level wire codes:               High 89 52 1.5 1.0-2.3       Low 231 207           Wire codes:               Very high 19 8 2.2 1.0-5.2       Very low 95 88        

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Myers et al. 1990 Distance to power line:         Age, sex, residence type, county of birth   <25 m 13 17 1.1 0.5-2.6     ≥25 m <50 m 7 15 0.7 0.3-2.0     ≥50 m <75 m 10 17 1.0 0.5-2.2     ≥75 m <100 m 8 9 1.5 0.6-4.0     <100 m 38 58 1.0 0.6-1.7     ≥100 m 336 530         Estimated field:             ≥0.1 µT 1 4 0.4 0.04-4.1     ≥0.03 µT <0.1 µT 8 4 2.6 0.8-9.0     ≥0.01 µT <0.03 µT 7 13 1.0 0.4-2.5     ≥0.01 µT <0.1 µT 15 17 1.4 0.6-3.0     ≥0.01 µT 16 21 1.2 0.6-2.6     <0.01 µT 358 567       Feychting  and Ahlbom 1993 Estimated field:         Sex, age, county, residence type, diagnosis year, SES, NO2   ≥0.3 µT 10 32 1.3 0.6-2.7     0.1-0.29 µT 14 47 1.2 0.6-2.3     ≥0.2 µT 12 46 1.1 0.5-2.1     0.1-0.19 µT 12 33 1.5 0.7-2.9     <0.1 µT 117 475       Olsen et al. 1993 Estimated field:         Age, sex, age at diagnosis   ≥0.4 µT 6 3 5.6 1.6-19     0.1-0.39 µT 4 17 0.7 0.2-2.0     ≥0.25 µT 6 11 1.5 0.6-4.1     0.1-0.24 µT 4 9 1.3 0.4-4.1     ≥0.1 µT 10 20 1.4 0.7-3.0     <0.1 µT 4 21 0.6 0.2-17     Not exposed, distant 16 49 0.9 0.5-1.6     Not exposed 1,677 4,698      

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Study Exposure Category Cases Observed Cases Expectedg Standardized Incidence Ratio 95% CIb Potential Confounders Addressedd Verkasalo et al. 1993 ≥ 0.2 µT 11 7.39 1.5 0.7-2.7 Age, sex   0.01-0.19 µT 129 137.17 0.9 0.8-1.1     ≥ 0.4 µT-yr 15   1.4 0.8-2.3     0.01-0.39 µT-yr 125   0.9 0.8-1.1   a Odds ratio calculated without consideration of possible confounders (ratio of exposed to unexposed cases divided by the ratio of exposed to unexposed controls). b 95% confidence intervals for the odds ratio calculated without consideration of possible confounders. c Odds radio adjusted statistically for possible confounding factors. d Includes all factors considered to be potential confounders whether or not statistical adjustments were made for them. e HCC, high current configuration. f LCC, low current configuration. g Cases expected on the basis of incidence data for the disease in the general population.

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields TABLE A5-9 Residential Electric-and Magnetic-Field Exposure and Cancer: Results of Cohort Studies Including Subjects of All Ages Study Exposure Description Number of Cases Observed SMRa 95% CIb Potential Confounders Addressedc McDowell 1986 Distance from power line for Leukemia:       Age, sex, calendar time   0-14 m 1 1.4 0.0-8.0     15-34 m 2 0.8 0.1-2.8     35-50 m 3 1.2 0.3-3.5     Lymphoma:           0-14 m 3 3.3 0.7-9.7     15-34 m 2 0.6 0.1-2.1     35-50 m 5 1.5 0.5-3.4     All cancers:           0-14 m 27 1.0 0.7-1.5     15-34 m 97 1.1 0.9-1.3     35-50 m 89 1.0 0.8-1.2   Schreiber et al. 1993 Wire codes:       Age, sex   High exposure 0         Low exposure 3 1.3 0.3-3.9     Hodgkin's disease:           High exposure 2 4.7 0.5-17.0     Low exposure 0         Non-Hodgkin's lymphoma:           High exposure 2 1.8 0.2-6.4     Low exposure 0         Brain tumors:           High exposure 0         Low exposure 3 2.0 0.4-5.7  

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Study Exposure Description Number of Cases Observed SMRa 95% CIb Potential Confounders Addressedc   All cancers:           High exposure 46 0.9 0.6-1.1     Low exposure 65 0.9 0.7-1.2   a Standard mortality ratio, ratio of observed number of deaths to the number expected based on mortality in the general population. b 95% confidence intervals for the odds ratio calculated without consideration of possible confounders. c Includes all factors considered to be potential confounders whether or not statistical adjustments were made for them.

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields TABLE A5-10 Residential Electric-and Magnetic-Field Exposure and Adult Leukemia: Results Study Exposure Description Number of Cases Number of Controls Crude ORa 95% CIb Potential Confounders Addressedc   Wire codes at time of longest residence: Age, sex, family income, race, cigarette smoking   Very high 5 6 0.8 0.2-2.9     High 21 23 0.8 0.4-1.7     Low 21 37 0.6 0.3-1.2     Very low 42 44         Wire codes at residence closest to reference date:     Very high 5 7 0.8 0.2-2.9     High 24 19 1.4 0.6-3.0     Low 26 38 0.8 0.4-1.6     Very low 42 52         Estimated field at longest residence:     >0.2 µT 14 18 0.8 0.3-1.8     0.05-0.199 µT 46 64 0.7 0.4-1.3     0.0-0.05 µT 29 28         Estimated field at residence closest to reference date:     >0.2 µT 23 25 1.0 0.5-2.0     0.05-0.1992 µT 70 92 0.8 0.5-1.4     0.0-0.052 µT 40 42      

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Study Exposure Description Number of Cases Number of Controls Crude ORa 95% CIb Potential Confounders Addressedc   Field measurement mean exposure for low power:     >0.2 µT     1.5 0.5-4.7     0.05-0.1992 µT     1.2 0.5-2.6     0.0-0.052 µT             Field measurement mean exposure; for low power:     >0.2 µT     1.6 0.5-5.0     0.05-0.1992 µT     0.6 0.3-1.2     0.0-0.052 µT           Coleman et al. 1989 Distance to substation, using population controls:     0-24 m 4 4 1.3 (0.3-5.3)     25-49 m 11 13 1.1 (0.5-2.5)     50-99 m 63 69 1.2 (0.8-1.8)     ≥100 m 112 145 — —   Youngson et al. 1991 Distance from power line:     <25 m 77 62 1.3 (0.9-1.8)     ≥25 m <50 m 60 47 1.3 (0.9-1.9)     ≥50 m <75 m 52 50 1.1 (0.7-1.6)     ≥75 m <100 m 47 53 0.9 (0.6-1.3)     <100 m 236 212 1.1 (0.9-1.4)     ≥100 m 2,908 2,932 — —  

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields Estimated magnetic field:         Age, sex, residence type   ≥0.3 µT 15 8 1.9 (0.8-4.4)     ≥0.1 µT 129 125 1.0 (0.7-1.5)   Feychting and Ahlbom 1994  Estimated magnetic field: Age, sex   ≥0.2 µT 26 83 1.0 0.7-1.7     0.1-0.19 µT 20 76 0.9 0.5-1.5     >0.09 µT 278 924 — —   a Odds ratio calculated without consideration of possible confounders (ratio of exposed to unexposed cases divided by the ratio of exposed to unexposed controls). b 95% confidence intervals for the odds ratio calculated without consideration of the possible confounders. c Includes all factors considered to be potential confounders whether or not statistical adjustments were made for them.

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Possible Health Effects of Exposure to Residential Electric and Magnetic Fields TABLE A5-11 Residential Electric-and Magnetic-Field Exposure and Adult Cancer: Results Study Exposure Description Number of Cases Number of Controls Crude ORa Adjusted 95% CIb Potential Confounders Addressedc Wertheimer and Leeper 1892 Wire codes:         Sex, age, socioeconomic status, onset age, urban exposure   VHCCd 108 74 2.2 1.5-3.2     OHCCe 330 298 1.7 1.2-2.2     OLCCf 642 659 1.5 1.1-1.9     End poleg 99 148       a Odds ratio calculated without consideration of possible confounders (ratio of exposed to unexposed cases divided by the ratio of exposed to unexposed controls). b 95% confidence intervals for the odds ratio calculated without consideration of possible confounders. c Includes all factors considered as potential confounders whether or not statistical adjustments were made for them. d VHCC, very high current configuration. e OHCC, ordinary high current configuration. f OLCC, ordinary low current configuration. g End pole, very low current configuration.