Subject: Melatonin Study performed by FHCRC and BPNL (fwd)
Date: Sat, 27 Jun 1998 052727 -0500 (CDT)
From: "Roy L. Beavers" <rbeavers@llion.org>
To: emfguru@hotmail.com
--------------------------------------------------
Hi everybody:
Peter DePippo sent the following. It is long, but it is an important
study ... so I forward it with a few comments:
1) I just sent to you Deb's report about the study underway at Lookout
Mountain; and I commented that "studying end-point illnesses may not
be the best way to conduct these studies where the 'damage' is still
in progress...." The study below is an example of the "other way" to
study for EMF effects, by looking for biological changes in progress,
i.e., identifying other "markers" to be measured.
2) The study below was under the direction of Richard Stevens of
Battelle Lab in Washington State. He was one of the "30" scientists
who just completed the EMF RAPID Working Group report that was reported-on
by Louis Slesin (the Minneapolis meeting which I also attended).
3) I intend to write my observations from that meeting separately in a
few days, BUT perhaps this one comment should not wait: I could not
understand the "short shrift" that was given to the whole melatonin issue
by that panel of researchers! Stevens did not speak up much on the
melatonin matter either. (I will offer "my" explanation later.)
4) Nevertheless, the study below is the first of its kind (re: EMF) that
may point to a more productive research technique we should expect to see
more of ... AND it does show an EMF "effect." However, there are also
a number of "effects" not observed where they might have been expected.
Cheerio....
Roy Beavers (EMFguru)
rbeavers@llion.org..............http://www.feb.se/EMF-L/EMF-L.html
................................It is better to light a single candle ...
than to curse the darkness...............................................
---------- Forwarded message ----------
Date: Fri, 26 Jun 1998 20:51:06 EDT
From: PDepippo@aol.com
To: rbeavers@mail.llion.org
Subject: Melatonin Study performed by FHCRC and BPNL
Roy,
I was able to obtain the abstract of the Melatonin Study performed by FHCRC
and BPNL and which was mentioned by one of our members a few weeks ago.
Regards,
Peter
Title: Relation Between Residential Magnetic Fields, Light-At-Night, and
Nocturnal Urine Melatonin Levels in Women (Urine Melatonin Study)
Project Start Date: April 1, 1994
Principal Investigators: William Kaune, Scott Davis, Richard Stevens
Institutions: EM Factors, Fred Hutchinson Cancer Research Center, and
Battelle Pacific Northwest Laboratories
OBJECTIVES:
The primary objective of this project is to determine whether exposure to
electromagnetic fields and/or light-at-night influences secretion of melatonin
as measured by levels of urinary melatonin metabolites in women with no
history of breast cancer. Secondary objectives include evaluating
seasonal variability and weekday to weekend variability of the exposure
assessments.
METHODS:
This study enrolled approximately 200 women who had already participated as
controls (women without breast cancer) in a case-control study of breast
cancer and exposure to power frequency magnetic fields and light-at-night
(parent study) conducted by the Fred Hutchinson Cancer Research Center.
Eligibility
in the parent study was restricted to women between the ages of 20 and 74
resident in King and Snohomish Counties, Washington, identified from
November 1992 to April 1995. All control women living in homes
classified in the parent study as Very High Current Configuration
according to the Wertheimer-Leeper code classification system were
targeted for enrollment. The remaining women were selected such that
approximately equal numbers would be included from homes with
the highest and lowest levels of measured indoor magnetic fields as
determined in the parent study.
The Urine Melatonin Study employed a two-part measurement design. Each
measurement session included three consecutive days separated by a period of
either three or six months. Exposure assessment for each measurement session
consisted of: 1) a brief in-person interview to obtain information on changes
in habits and residence characteristics since participating in the parent
study (or the previous measurement session); 2) 72-hour continuous
measurement of magnetic field levels and light intensity in the
participant's bedroom (using and EMDEX II meter with an adapted light
sensor); 3) 72-hour continuous measurement of personal magnetic field
exposure (using an EMDEX Lite meter) and corresponding
activity diary; 4) collection of total nocturnal urine excreted by
participants for three consecutive nights. Urine samples were assayed
for creatinine and the primary urinary metabolite of melatonin,
6-sulphatoxymelatonin. Wire code data
was also available for each participant from the parent study.
Participants were enrolled over a nine-month period. Actual data collection
took approximately 14 months to complete. The study participants proved to be
highly motivated and able to follow detailed protocols. Of the 203
participants enrolled in the first measurement session, 199 participants
(98%) completed all three days of data collection. Only three
participants did not participate in Session 2. Of the 200 who did, 193
(97%) completed all three days of data collection.
RESULTS:
This study provides intriguing evidence suggesting that increasing magnetic
field strength, as measured in a woman's bedroom during the night, is
associated with a reduction in the concentration of 6-sulphatoxymelatonin
in the woman's urine in the same night. The relationship was present
after accounting for the effects on 6-sulphatoxymelatonin of hours of
darkness during the night (a measure reflecting season of the year), age,
body mass index, current alcohol consumption, and current use of
medications known to reduce melatonin levels (beta blockers, calcium
channel blockers, and psychotropics). The reduction in
6-sulphatoxymelatonin was seen primarily among women who used these
medications, and was strongest during the time of the year with the
longest period of daylight hours. Similar findings were observed when
the magnetic field exposure measure consisted of the proportion of
measurements during the night, 3- 2 mG.
Based upon findings in this study within the range of bedroom magnetic field
levels measured (up to 15 mG), during the time of the year when reduction in
6-sulphatoxymelatonin levels were the largest (summer), it is estimated that
among women using drugs that affect melatonin, a two-fold increased in
nighttime exposure to magnetic field would result in a 8% decrease in
urinary 6-sulphatoxymelatonin concentration.
The study also found that decreasing urinary 6-sulphatoxymelatonin levels were
significantly associated with increasing daily hours of light (reflecting time
of year or season), increasing age, alcohol consumption on the night of
measurement, and increasing body mass index (increasing obesity). These
effects were observed consistently across all hypothesis tested. Of
particular note in this study was the very strong and consistent
reduction in 6-sulphatoxymelatonin associated with the use of medication
suspected a priori to affect melatonin levels.
There was, however, no association observed in the study between the following
measures of exposure and nocturnal urinary 6-sulphatoxymelatonin levels: 1)
wire code, 2) short-term variability in nighttime bedroom magnetic field
levels; 3) 24-hour magnetic field exposure as measured by a personal
meter; 4) the proportion of 24-hour personal magnetic field 3 2 mG; 5)
short-term variability in 24-hour personal magnetic field level; 6)
proportion of nighttime bedroom light measurements 3 10 lux; and 7)
number of times the participant reported getting up and turning on a
light during the night. There was also no association observed between
nocturnal urinary 6-sulphatoxymelatonin levels and
menopausal status, height, currently smoking, current use of an electric
blanket, or use of an electric blanket within the past month. One set of
results was opposite to that predicted. After accounting for factors listed
above, there was a significant decrease in urinary 6-sulphatoxymelatonin
concentration associated with longer periods of uninterrupted dark during the
night. The magnitude of this association was similar in both those who did
and did not report using medications that can affect melatonin, and was
apparent throughout the year, although weakest in winter months.
A final report was submitted to EPRI in November, 1997, and has been
published as EPRI Report TR-107242, Volumes 1 and 2.
Archive provided courtesy of WaveGuide, http://www.wave-guide.org
Reprinted with permission of Roy Beavers, http://www.feb.se/EMF-L/EMF-L.html