27.11.2007 Patrizia Frei, MSc
description
Transcript of 27.11.2007 Patrizia Frei, MSc
QUALIFEXHealth related quality of life and radio frequency electromagnetic field exposure: Prospective cohort study
27.11.2007Patrizia Frei, MScDepartment of Social and Preventive Medicine, University of Bern, Switzerland
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
2
The electromagnetic Spectrum
Static EMF
Low frequency
EMF
Radio frequency
EMF
Infra-red
Light UV Ionizing Radiation
Electromagnetic Fields(EMF)
Optical Radiation
Non-ionizing Radiation (NIS)
>Radio frequency electromagnetic fields (RF EMF)
Basics (1)
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
3
Basics (2)
> Radio frequency electromagnetic fields (RF EMF):— Radio transmitters— Television transmitters— Tetrapol (radio communication for authorities)— Mobile phones (GSM and UMTS) — Mobile phone base stations (GSM and UMTS)— Cordless phones (DECT)— Wireless LAN
> Non-specific symptoms that are frequently attributed to RF EMF:— headache — dizziness — tiredness— discomfort— itching skin — sleep disorder
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
4
QUALIFEX: Study Overview
Exposimeter Study:
• Measurements with exposimeter• Diary• Questionnaire on exposure
200 participants
Main Study:
• Questionnaire on expo- sure and health • Follow-up after one year
2000 participants
Sleep Study:
• Measurement with Actimeter• Sleep diary
120 participants
Year 1(2007)
Years 2, 3 & 4(2008 until 2010)
Exposure assessment
method
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
5
QUALIFEX: Study Overview
Exposimeter Study:
• Measurements with exposimeter• Diary• Questionnaire on exposure
200 participants
Main Study:
• Questionnaire on expo- sure and health • Follow-up after one year
2000 participants
Sleep Study:
• Measurement with Actimeter• Sleep diary
120 participants
Year 1(2007)
Years 2, 3 & 4(2008 until 2010)
Exposure assessment
method
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
6
Study area
Exposimeter
Exposimeter study
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
7
Exposimeter study: Statistical methods
> Summary statistics:— Median and interquartile range
> Statistical analysis:— Significance test of group difference:
Wilcoxon rank-sum (Mann-Whitney) test— Level of significance:
* 0.01 < p < 0.05** 0.001 < p < 0.01 *** p < 0.001
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
8
Preliminary results (1): example of a daily exposure pattern
bedroom
traincall with cordless phonestation
tram
train
WLANoffice
lunch break
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
9
Preliminary results (2): Results from the first 140 study participants
> Median exposure over one week:0.20 V/m (interquartile range: 0.15-0.27 V/m)
> Contributions of the different sources to the total exposure
6% 5%
0%
27%
32%
26%
4%
Radio transmitter
Television transmitter
Tetrapol
Mobile phone
Mobile phone base station
Cordless phone
Wireless LAN
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
10
Preliminary results (3): Comparison of different groups
1. Living close to mobile phone base stations or a radio/TV transmitter (fixed transmitter)
2. Owning a cordless phone
3. Owning a mobile phone
4. Owning WLAN
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
11
1. Living close to a fixed transmitter
n Total exposure (V/m)
Exposure to fixed transmitter (V/m)
People living close to a fixed transmitter (highly exposed group)
36 0.24 0.18
Unselected volunteers (reference group)
104 0.20 0.08
Wilcoxon rank-sum test p=0.004 p<0.0001
***
0
0.05
0.1
0.15
0.2
0.25
Radiotransmitter
Televisiontransmitter
Tetrapol Mobilephone
Mobilephone base
station
Cordlessphone
WirelessLAN
V/m
highly exposed group
reference group
*
*****
**
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
12
2. Owning a cordless phone
n Total exposure (V/m)
Exposure to cordl. phone (V/m)
Persons owning a cordless phone 106 0.21 0.09
Persons not owning a cordl. phone 30 0.19 0.04
Wilcoxon rank-sum test p=0.127 p<0.0001
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
Radiotransmitter
Televisiontransmitter
Tetrapol Mobilephone
Mobilephone base
station
Cordlessphone
WirelessLAN
V/m
DECT
No DECT
***
*
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
13
3. Owning a mobile phone
n Total exposure (V/m)
Exposure to mobile phone (V/m)
Persons owning a mobile phone 119 0.20 0.10
Persons not owning a mob. phone 17 0.17 0.06
Wilcoxon rank-sum test p=0.013 p=0.003
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
Radiotransmitter
Televisiontransmitter
Tetrapol Mobilephone
Mobilephone base
station
Cordlessphone
WirelessLAN
V/m
Mobile phone
No mobile phone
**
***
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
14
4. Owning WLAN
n Total exposure (V/m)
Exposure to WLAN (V/m)
Persons owning WLAN 41 0.20 0.03
Persons not owning WLAN 92 0.20 0.02
Wilcoxon rank-sum test p=0.826 p<0.001
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
Radiotransmitter
Televisiontransmitter
Tetrapol Mobilephone
Mobilephone base
station
Cordlessphone
WirelessLAN
V/m
WLAN
No WLAN
**** *
ISEE CEEC Conference, Czech Republic, Nov 26th-29th
15
Conclusions and Outlook
> In our sample of 140 persons, the main contributions to the total exposure is due to mobile phones, cordless phones and mobile phone base stations
> In terms of total exposure, there are significant differences between persons living close to transmitters and those not, and between people owning a mobile phone and those not
> Further multivariable analyses are needed to investigate combined effects of all predictors (multiple linear regression model)