EMF Health Effect 2003 10 20 21-29 2-10 - - ( ) area spot measurement - - 1
(Exposure) Exposure (Exposure Assesment) EMF Unknown to mechanism Health Effect (Effect) Unknown to mechanism Behavior pattern (Micro- Environment) Research Questions 2
24 time-spend fraction 24 TWA S T U D Y 1 S T U D Y 2 Time-activity pattern / Micro-Environment Spot (EMDEX II) (EMDEX Lite) - 30-24 - - (10 ) Spearman rank correlations & Regression Analysis 3
: 2003 2 6 : EMDEX II (2 ) EMDEX Lite (4 ) : 2002 12-2003 3 : 2003 6-8 Pilot survey : 2003 3 Main Survey : 2003 6-9 : 53 : 2003 6 9 : 53 EMDEX II EMDEX Lite - Micro-Environments - 16.8 6.6 3.8 cm - 784 g - 3- RMS - - 12.0 6.0 2.5 cm - 170 g - 3- RMS 4
QA EMDEX II : 2003 2 EMDEX Lite : 2003 5 - : ± 2 % QA/QC QC With ELF-MFs Sources - Electric Appliances -Transmission - Distribution Background No ELF-MFs Source - Electric appliances - Transmission - Distribution SOP - - (1999) Pilot Survey - Subject 10-10, 20, 30, 60 PC / EMDEX II 5 30 24 / (2003) X X PC X X / 5
EMDEX Lite T-test ANOVA-test Pearson Correlation Analysis Time-Weighted Average Model 6
0.007 0.0004 Magnetic Field (mg) 0.0003 Electric Field (kv/m) 0.006 Oct/01/2003 10:55:30 PM 11:00 PM 11:05 PM Time 0.0002 Oct/01/2003 11:06:30 PM Figure 1. An example of 60 Hz magnetic fields in background level. 2.2 0.0004 2.2 0.0004 2.0 2.0 1.8 1.8 1.6 1.6 1.4 1.4 Magnetic Field (mg) 1.2 1.0 0.8 0.0003 Electric Field (kv/m) Magnetic Field (mg) 1.2 1.0 0.8 0.0003 Electric Field (kv/m) 0.6 0.6 Event 1 0.4 0.4 0.2 0.2 0.0 02:25 AM 02:30 AM 02:35 AM Oct/02/2003 02:23:49 AM Time 0.0002 Oct/02/2003 02:39:59 AM 0.0 0.0002 02:25 AM 02:30 AM 02:35 AM 02:40 AM Oct/02/2003 02:23:50 AM Time Oct/02/2003 02:40:30 AM Figure 2. Comparison of two 60 Hz magnetic field measurements in same area and same measured time. 7
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 May/13/2003 01:17:49 PM 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.0007 0.0006 0.0005 01:30 PM 01:45 PM 02:00 PM 02:15 PM Time May/13/2003 02:25:39 PM 0.0007 0.0006 0.2 0.0005 05:30 PM 05:40 PM 05:50 PM 06:00 PM May/10/2003 Time May/10/2003 05:24:21 PM 06:01:41 PM Bedroom (on mode) Bedroom (off mode) 1.0 0.0007 0.9 Bedroom (off mode) 0.8 Magnetic Field (mg) 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0006 Current (A) 0.0 11:40 AM 11:50 AM 12:00 PM 0.0005 Kitchen (on mode) Kitchen (off mode) Scale Down Time May/03/2003 May/03/2003 11:32:17 AM 12:08:17 PM Kitchen (off mode) Magnetic Field (mg) Current (A) Magnetic Field (mg) Current (A) Living room (on mode) Living room (off mode) Scale Down Living room (off mode) Figure 3. Example of 60 Hz magnetic field measurements within homes. On mode is use of electric appliances and Off mode is not use of them except kitchen. Table 1. Time weighted average (TWA) of 60 Hz magnetic field measurements in micro-environments away from transmission powerlines. > 50 VDTs < 30 VDTs 1. AM : Arithmetic Mean 2. GM : Geometric Mean 8
Table 1. Time weighted average (TWA) of 60 Hz magnetic field measurements in micro-environments away from transmission powerlines. < 2000c c > 3000c c Table 1. Time weighted average (TWA) of 60 Hz magnetic field measurements in micro-environments away from transmission powerlines. 9
Table 2. Summary of subject characteristics in this study. 1. N : Number of subjects 2. Standard deviation Table 3. Fraction of time spent by subject in each micro-environments. awake Home sleep class School ground Educational institutes PC rooms Other Mean hours±sd 1 7.4±3.7 8.6±2.8 5.1 ±1.3) 1.4 ±1.1 2.3 ±1.3 1.8 ±1.1 1.5 ±0.9 Fraction (%) 26.4 30.9 18.1 4.8 8.1 6.4 5.3 Total (%) 57.3 22.9 8.1 6.4 5.3 1. N : Number of subjects 2. Standard deviation 10
Figure 4. Example of 24 hr personal exposure to MFs during measurement. a, in a class of school; b, in a pc room; c, in a educational institutes; d, awake in home e, sleep in home; f, in a class of school Table 4. Descriptive summary of exposure to MFs by type of micro-environments. awake sleep class ground 1. * : 0.01 < p-value 0.05, 2. *** : p-value 0.001 3. SD : standard deviation, 4. GSD : geometric standard deviation 11
Table 5. Results of statistical test between various parameters and 24 hr personal exposure les s than 31 min (47) more than 31 min (6) les s than 18 EA (25) more than 18 EA (28) 1. * : 0.01 < p-value 0.05, 2. ** : 0.001 < p-value 0.05, 3. *** : p-value 0.001 Table 5. Results of statistical test between various parameters and 24 hr personal exposure le s s than 30m (16) les s than 30 hr (6) les s than 1m (19) les s than 1 hr (6) 1. * : 0.01 < p-value 0.05, 2. ** : 0.001 < p-value 0.05, 3. *** : p-value 0.001 12
Figure 5. Relationship between measured personal exposure and measurement at home. Figure 6. Relationship between measured personal exposure and measurement in school. 13
,. :,,, PC ( & ) Time-spend fraction : (57.3%), (22.9%) -24 : 1.14 mg - : 1.65 mg ( - 2.07 mg, - 1.38 mg) - : 0.95 mg ( - 0.64 mg, - 1.60 mg) 24 : (r=0.95),,. 14
: : - sample size -. 15