STATE OF VERMONT
PUBLIC SERVICE BOARD
Petition of Vermont Transco, LLC, and
Vermont Electric Power Company, Inc.
(collectively, “VELCO”), and Central Vermont
Public Service Corporation (“CVPS”) for a
Certificate of Public Good, pursuant to 30
V.S.A. § 248, for the “Southern Loop Project,”
located in Vernon, Guilford, Brattleboro,
Dummerston, Newfane, Brookline, Townshend,
Grafton, Windham, Andover, Chester, Ludlow
and Cavendish, Vermont, consisting of the
following elements: (1) a new, approximately
51-mile, 345 kV transmission line between
Vernon-Cavendish, to be built parallel to and
within the same utility right-of-way as
VELCO’s existing Vernon-Cavendish 345 kV
line; (2) a new VELCO 345/115 kV Vernon
substation, to be located just north of the
Vermont Yankee Nuclear Power Station; (3) a
new 345/115/46 kV Newfane substation; (4) a
new, approximately one-mile, 345 kV
transmission line loop between the new
Newfane substation and the new VernonCavendish 345 kV line; (5) expansion of
VELCO’s Coolidge substation in Cavendish,
Vermont; and (6) the implementing of
incremental energy efficiency to defer
transmission upgrades in Southern Vermont
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Docket No. ____
PREFILED TESTIMONY OF
PETER ALEXIS VALBERG, Ph.D.
ON BEHALF OF
PETITIONERS
November 8, 2007
The purpose of Dr. Valberg’s testimony is provide an overview of the current status of
health-effect research and regulatory positions with regard to general public exposure to
power-line electric and magnetic fields. Also, Dr. Valberg reviewed the EMF
calculations specifically made for the Southern Loop Project and evaluated the potential
for health impacts from the exposures that might occur to the general public and nearby
residences.
TABLE OF CONTENTS
1. Introduction and Qualifications of Dr. Valberg........................................................1
2. Overview of EMF Definitions, Sources, and Magnitudes ........................................5
3. Expert Opinion and Regulatory Guidance About EMF Power Line Exposure ....9
4. Summary of the EMF Calculated for the Project ...................................................31
5. Summary of Analysis and Conclusions ....................................................................36
6. Conclusion ..................................................................................................................41
EXHIBITS
Exhibit Petitioners PAV -1
Resume of Peter A. Valberg, Ph.D.
Exhibit Petitioners PAV-2
Regulatory Proceedings in which Dr. Valberg has
Testified on EMF
Exhibit Petitioners PAV-3
Update on Scientific Research Regarding Potential
Health Effects of Power-Line Electric and Magnetic
Fields (EMF) (Sept. 2007)
STATE OF VERMONT
PUBLIC SERVICE BOARD
Petition of Vermont Transco, LLC, and
Vermont Electric Power Company, Inc.
(collectively, “VELCO”), and Central Vermont
Public Service Corporation (“CVPS”) for a
Certificate of Public Good, pursuant to 30
V.S.A. § 248, for the “Southern Loop Project,”
located in Vernon, Guilford, Brattleboro,
Dummerston, Newfane, Brookline, Townshend,
Grafton, Windham, Andover, Chester, Ludlow
and Cavendish, Vermont, consisting of the
following elements: (1) a new, approximately
51-mile, 345 kV transmission line between
Vernon-Cavendish, to be built parallel to and
within the same utility right-of-way as
VELCO’s existing Vernon-Cavendish 345 kV
line; (2) a new VELCO 345/115 kV Vernon
substation, to be located just north of the
Vermont Yankee Nuclear Power Station; (3) a
new 345/115/46 kV Newfane substation; (4) a
new, approximately one-mile, 345 kV
transmission line loop between the new
Newfane substation and the new VernonCavendish 345 kV line; (5) expansion of
VELCO’s Coolidge substation in Cavendish,
Vermont; and (6) the implementing of
incremental energy efficiency to defer
transmission upgrades in Southern Vermont
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)
)
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)
)
)
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Docket No. ____
PREFILED TESTIMONY OF
PETER ALEXIS VALBERG, Ph.D.
ON BEHALF OF
PETITIONERS
1
2
1.
Q1.
Introduction and Qualifications of Dr. Valberg
Please state your name, business address, and qualifications.
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 2 of 41
1
A1.
My name is Peter Alexis Valberg. I am a Principal at Gradient Corporation, 20
2
University Road, Cambridge, MA 02138. I specialize in the areas of inhalation
3
toxicology, biological modeling of human exposure to environmental agents,
4
ionizing / non-ionizing radiation, and human health risk assessment. I have
5
extensively researched and studied the links between human health and specific
6
agents such as air pollutants, groundwater contaminants, radio wave frequencies
7
(“RF”), and electric and magnetic fields (“EMF”).
8
9
I hold an A.B. degree, summa cum laude, in Physics and Mathematics from
10
Taylor University, both M.A. and Ph.D. degrees in Physics from Harvard
11
University, and an M.S. degree in Human Physiology from the Harvard
12
University School of Public Health (“HSPH”).
13
14
For 25 years, I served as a faculty member in the Department of Environmental
15
Health at HSPH, where I researched and taught toxicology, cell biology,
16
environmental health, and public health. One of the research grants I directed at
17
HSPH was funded by the National Cancer Institute, and was on the topic of
18
“Magnetic Field Effects on Macrophages” (where “macrophages” are a class of
19
lung cells that clean the lung of particles deposited there from the dust present in
20
the air we breathe).
21
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 3 of 41
1
I have served on advisory panels for the National Institutes of Health (“NIH”), the
2
Health Effects Institute, and the Environmental Protection Agency (“EPA”). I am
3
a member of the International Society for Environmental Epidemiology, the
4
Health Physics Society, the Bioelectromagnetics Society, and the Committee on
5
Man and Radiation (“COMAR”). I am on the Board of Directors of the
6
Bioelectromagnetics Society.
7
8
During the period of time when Harvard University (Center for Risk Analysis)
9
had the two active committees, namely the “Harvard Advisory Committee on
10
EMF and Human Health” and the “Peer Review Board on Cellular Technology
11
and Human Health,” I served on these committees. I have assisted the Health
12
Effects Institute (Boston, MA) in determining the feasibility of launching an EMF
13
research program, and I have published a summary document on “EMF
14
Mechanisms” in the journal Radiation Research. At the request of the
15
International Congress on Radiation Research (“ICRR”), I organized and chaired
16
a symposium on “Physical aspects of EMF / RF effects on Biological Systems,” at
17
the 11th Annual ICRR meeting in Dublin, Ireland (1999). In 2006, I was asked to
18
present a lecture on how EMF interacts with living organisms by the Cyprus
19
International Institute for the Environment and Public Health in a symposium on
20
“Electromagnetic Fields: Sources, Health Effects, and Regulations,” which took
21
place in Nicosia, Cyprus. For the Harvard School of Public Health, I helped
22
organize a conference in the Boston area on “Childhood Leukemia: Electric and
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 4 of 41
1
Magnetic Fields as Possible Risk Factors.” A summary of this workshop was
2
published (2003) in the journal Environmental Health Perspectives. I have
3
worked with the World Health Organization (“WHO”) on analyzing the EMF that
4
occur in the context of cellular telephones, and with the State of Connecticut
5
(Connecticut Siting Council) on how EMF health-based exposure limits relate to
6
siting policies for electric-power transmission lines. A summary of the WHO
7
work was published (2007) in the journal Environmental Health Perspectives.
8
9
My resume is attached to my prefiled testimony as Exhibit Petitioners PAV-1.
10
11
Q2.
What is the purpose of your testimony in this proceeding?
12
A2.
I was asked by Vermont Electric Power Company, Inc. (“VELCO”) to assess the
13
potential health effects of EMF exposure related to the proposed Southern Loop
14
Project (“Project”), which is the subject of this proceeding. A description of the
15
Project is found in the Prefiled Testimonies of Mssrs. LaForest, Barrett and
16
McNamara.
17
18
Q3.
Please summarize your testimony.
19
A3.
Section 2 provides an overview of what is known about EMF and their possible
20
effects on human health. Section 3 summarizes expert opinion and applicable
21
regulatory guidance as it applies to potential EMF health impacts. Section 4
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 5 of 41
1
assesses the potential health effects of the EMF calculated for the Project. Section
2
5 summarizes the conclusions of the analysis.
3
4
My review of (1) the current status of biological, public health, and medical
5
research on the possible effects of power-line EMF on health, (2) the current
6
scientific consensus documents and regulatory guidelines on allowable EMF
7
exposures, and (3) the EMF levels predicted to be associated with this Project,
8
leads me to conclude that the projected power-line EMF exposures due to
9
construction of the Project are not likely to lead to adverse effects on health for
10
people living, working, or walking in the vicinity of the affected rights-of-way
11
(“ROWs”).
12
13
2.
Overview of EMF Definitions, Sources, and Magnitudes
14
Q4.
Where does EMF come from?
15
A4.
All matter contains electrically-charged particles. Most objects are electrically
16
neutral because positive and negative charges are present in equal numbers.
17
When the balance of electric charges is altered, we experience electrical effects,
18
such as the static-electricity attraction between a comb and our hair or drawing
19
sparks after walking on a synthetic rug in the wintertime. Electrical effects both
20
in nature and in society’s use of electricity (generation, transmission,
21
consumption) produce EMF.
22
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 6 of 41
1
The work put into electrically charging something is measured by the voltage.
2
The units of work-per-unit-charge are volts or kilovolts (kV; 1 kV = 1,000 V).
3
Voltage is the “pressure” of the electricity, and can be envisioned as analogous to
4
the pressure of water in a plumbing system. Electric charges push and pull on
5
each other. Opposite charges (i.e., + and -) attract and like charges (i.e., + and +,
6
or - and -) repel. Scientists explain these forces by saying that each electric
7
charge generates an electric field that exerts force on other nearby charges. That
8
is, the electric field is a measure of force-per unit-charge and is usually expressed
9
in units of volts per meter (V/m).
10
11
When electric charges move, an electric current exists, and the current generates a
12
magnetic field. The units for electric current are amperes (A) and are a measure
13
of the “flow” of electricity. Electric current can be envisioned as analogous to the
14
flow of water in a plumbing system. The current of moving electric charges
15
produces a magnetic field that exerts force on other moving charges. That is, the
16
magnetic field is a measure of the force-per-unit-length-of-wire per unit current
17
and is usually expressed in units of gauss (G) or milligauss (mG), where 1 G
18
=1,000 mG. An equivalent unit for magnetic field levels that is sometimes used is
19
the microtesla (μT), where 1 μT = 10 mG.
20
21
Just like electric charges exert force on one another, current-carrying wires exert
22
force on each wire, and an application of this fact is used in electric motors, where
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 7 of 41
1
magnetic field forces turn electricity into mechanical work. Conversely,
2
electricity-generating turbines use heat energy to rotate loops of wire through
3
magnetic fields, thereby converting mechanical energy of the turbine into electric
4
power output.
5
6
Q5.
Where do people encounter EMF in everyday life?
7
A5.
Everyone is exposed to a wide variety of natural and man-made electric and
8
magnetic fields. EMF fields can be steady (often called “DC fields”) or can vary
9
in time (often called “AC fields”). When the time variation of interest
10
corresponds to that of power line currents, i.e., 60 changes per second, the fields
11
are called “60 Hz” EMF.
12
13
Man-made magnetic fields are common in everyday life. Many childhood toys
14
contain magnets. “Permanent magnets” generate strong, steady magnetic fields.
15
Typical toy magnets (e.g., “refrigerator-door” magnets) produce 100,000 -
16
500,000 mG. Magnetic resonance imaging (“MRI”) is a medical diagnostic
17
procedure that puts humans in much larger fields (20,000,000 mG) and is
18
preferred over an X-ray because adverse health risks are much lower. These two
19
sources of magnetism are primarily DC, or steady in time; however, if the
20
magnets move and rotate, or if your body moves and rotates relative to the
21
magnet, then fields become time-varying, or AC.
22
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 8 of 41
1
The earth’s atmosphere produces slowly varying electric fields (about 100 to
2
10,000 V/m) that occasionally discharge dramatically, as lightning strikes. Also,
3
magnetic fields are produced by the earth’s core and can be easily demonstrated
4
with a compass needle. The size of the earth’s magnetic field in the Northeast
5
U.S. is about 570 mG. Knowing the strength of the earth’s EMF provides a
6
perspective on the size of power-line EMF. The earth’s steady EMF do not have
7
the 60-cycles-per-second (60-Hz) time variation characteristic of power-line
8
EMF, but are otherwise indistinguishable. For example, a magnet spinning at 60
9
cycles per second will produce a magnetic field indistinguishable from the
10
magnetic fields produced by an appropriate magnitude of 60-Hz power-line
11
current.
12
13
Electric power transmission lines, distribution lines, and the electric wiring in
14
buildings carry AC currents and voltages that change size and direction at a
15
frequency of 60 Hz. These 60-Hz currents and voltages produce 60-Hz EMF.
16
The size of the magnetic field is proportional to the current, and the size of the
17
electric field is proportional to the voltage. The EMF produced by transmission
18
lines, electrical wires, and electrical equipment decrease rapidly as the distance
19
away from the source increases. When EMF are produced by different sources
20
(e.g., adjacent wires), the fields may partially add or partially cancel. That is, the
21
size of the net EMF produced will be somewhere in the range between the sum of
22
individual fields and the difference of the individual fields. Inside residences,
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 9 of 41
1
typical baseline 60-Hz magnetic fields (away from appliances) range from 0.5 to
2
2.0 mG. EMF inside the home arise from electric appliances, outdoor distribution
3
wiring, indoor wiring, and grounding currents. The power-line, 60-Hz magnetic
4
fields add or subtract to the steady field of the earth (570 mG), so that the sum
5
total magnetic field has both a steady and a time-varying part.
6
7
Higher magnetic field levels are found near operating appliances. For example,
8
can openers, mixers, blenders, refrigerators, fluorescent lamps, electric ranges,
9
clothes washers, toasters, portable heaters, vacuum cleaners, electric tools, and
10
many other appliances produce magnetic fields of size 40 – 300 mG at distances
11
of 1 foot. 1 Magnetic fields from personal-care appliances held within ½ of a foot
12
(e.g., shavers, hair dryers, massagers) can produce 600 – 700 mG. In the school
13
and work environment, copy machines, vending machines, video-display
14
terminals, electric tools, lights, and motors are all sources of significant power-
15
line magnetic fields.
16
17
3.
18
Exposure
19
Q6.
20
Expert Opinion and Regulatory Guidance About EMF Power Line
What is the state of scientific knowledge about the health effects of exposure to
power line EMF?
1
National Institute of Environmental Health Sciences, Electric and Magnetic Fields Associated
with the Use of Electric Power, Questions and Answers, NIH Publication 02-4493 (2002).
Research Triangle Park, NC. 64 pp. (http://www.niehs.nih.gov/emfrapid/booklet/home.htm ).
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 10 of 41
1
A6.
Evidence available from scientific research on EMF and from human experience
2
with EMF exposures does not establish that typical levels of power-line EMF are
3
hazardous to health.
4
5
EMF epidemiology studies have received the most attention. “Epidemiology” is a
6
statistical science that looks for correlations between patterns of disease
7
occurrence and patterns of human lifestyle, diet, environment, or exposure. An
8
epidemiologic study published in 1979 2 suggested that living near electric power
9
distribution lines was linked to an increased risk of childhood cancer. In this and
10
a number of other studies, the actual EMF levels to which children had been
11
exposed were unknown, so the researchers developed a surrogate for “past EMF
12
exposure” that was based on the proximity, number, and size of electric-utility
13
distribution lines near the homes. This summary description of the electric power
14
distribution line configuration near a home was designated as its “wire code.”
15
Homes with high wire codes (and higher presumed EMF levels) were found to be
16
slightly more common among cancer cases as opposed to among children selected
17
as “controls,” that is, those individuals selected from the population not having
18
cancer. This was the basis for the authors concluding that EMF may be a risk
19
factor for childhood cancer.
20
2
Wertheimer N.; Leeper E.; Electrical Wiring Configurations and Childhood Cancer, American J.
Epidemiology 109:273-284 (1979).
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 11 of 41
1
After this first study in 1979, a number of other investigators examined
2
associations between disease and the “wire code” classification of homes. If an
3
association was seen with the wire code classification, it was interpreted as
4
showing an effect of EMF on the disease being studied. However, these follow-
5
up studies reported associations with wire code that were small in magnitude, and
6
inconsistent. Moreover, the associations often weakened or disappeared when
7
actual measured magnetic fields were substituted in place of wire codes. It was
8
found that the wire codes were poor surrogates for actual EMF exposure, but
9
rather tended to be good surrogates for non-EMF factors such as traffic density,
10
age of the home, rental vs. ownership, and assessed value of the home. This made
11
it unlikely that the wire code associations with cancer risk were actually an effect
12
of EMF exposure per se. That is, it was not possible to establish that EMF
13
exposure was a casual factor in the associations reported. 3
14
15
Q7.
16
17
What are the most important studies undertaken in recent years concerning the
possible risks that EMF pose to humans?
A7.
Literally hundreds of EMF research studies have been published since the 1979
18
study by Wertheimer and Leeper in Denver, Colorado, reported a statistical
19
association between “wire codes” and childhood cancers in certain residential
20
neighborhoods. It would be difficult to say which of these studies are the most
21
important ones, because each study focuses on a particular hypothesis, and the
3
Ahlbom A.; Cardis E.; Green A.; Linet M.; Savitz D.; Swerdlow A.; Review of the Epidemiologic
Literature on EMF and Health, Environ Health Perspectives 109 (Suppl. 6):911-33 (2001).
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 12 of 41
1
range of possible correlations that can be examined is large. Some of the most
2
important work was done under the auspices of the National Institute of
3
Environmental Health Sciences (“NIEHS”). NIEHS had a program called “EMF
4
RAPID” that funded laboratory research to determine what, if any, aspects of
5
EMF interaction with biological systems had the potential to express themselves
6
as adverse disease outcomes. The conclusion of this research program is
7
summarized by NIEHS as follows: 4
“The NIEHS believes that the probability that ELF-EMF
exposure is truly a health hazard is currently small. The
weak epidemiological associations and lack of any
laboratory support for these associations provide only
marginal, scientific support that exposure to this agent is
causing any degree of harm.” (p. 52, of the June 2002
NIEHS booklet “EMF Questions and Answers”)
8
9
10
11
12
13
14
15
Despite the lack of supporting laboratory evidence for EMF effects, 5, 6
16
epidemiologic analyses have continued over recent years, and the following list of
17
epidemiological articles, reviews, and analyses released within the past 8 years
18
provides an overview of the epidemiologic literature:
19
1.
Ahlbom A, Day N, Feychting M, Roman E, Skinner J, Dockerty J. et al.,
20
A Pooled Analysis of Magnetic Fields and Childhood Leukemia. British
21
J. Cancer 83:692-8 (2000).
4
National Institutes of Environmental Health Sciences (NIEHS), Health Effects From Exposure to
Power-Line Frequency Electric and Magnetic Fields, NIH# 99-4493 (1999). Research Triangle
Park, NC (http://www.niehs.nih.gov/emfrapid/booklet/reviews.htrn ).
5
Boorman G.A., McCormick D.L.; Findlay LC.; Hailey LR.; Gauger J.R.; Johnson T.R.; et al.
Chronic Toxicity Oncogenicity Evaluation of60 Hz (Power Frequency) Magnetic Fields in F344/N
Rats, Toxicologic Pathology 27:267-78 (1999).
6
McCormick D.L.; Boorman G.A.; Findlay J.C.; Hailey J.R.; Johnson T.R.; Gauger R., et al.
Chronic Toxicity/Oncogenicity Evaluation of60 Hz (Power Frequency) Magnetic Fields in
B6C3F1 Mice, Toxicologic Pathology 27:279-85 (1999).
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 13 of 41
“When the authors pooled nine epidemiology studies that
included long-term measurements of magnetic fields, they
found a relative risk of 2.0 (1.27-3.13) for childhood
leukemia in the children with average exposures of 4 mG or
greater. For children with lower average exposures, no
significant elevation of childhood leukemia was found in
the pooled studies.” The authors state that “The
explanation for the elevated risk is unknown, but selection
bias may have accounted for some of the increase.”
1
2
3
4
5
6
7
8
9
10
2.
California Department of Health Services (CADHS), An Evaluation of the
11
Possible Risks From Electric and Magnetic Fields (EMF) From Power
12
Lines, Internal Wiring, Electrical Occupations and Appliances, California
13
EMF Program, 1515 Clay Street, 17th Floor, Oakland, CA 94612 (2002).
14
(Available:
15
http://www.dhs.ca.gov/ehib/emf/RiskEvaluation/riskeval.html):
16
17
18
19
20
21
22
23
“Three epidemiologists who worked for the California
Department of Health Services (DHS) reviewed studies
about possible health problems from electric and magnetic
fields (EMFs) […] To one degree or another, all three of
the DHS scientists were inclined to believe that EMFs can
cause some degree of increased risk of childhood leukemia,
adult brain cancer, Lou Gehrig’s Disease [ALS], and
miscarriage.”
24
3.
Greenland S., Sheppard A.R., Kaune W.T., Poole C, Kelsh M.A. A
25
Pooled Analysis of Magnetic Fields, Wire Codes, and Childhood
26
Leukemia, Childhood Leukemia-EMF Study Group, Epidemiology 11
27
:624-634 (2000):
28
29
30
31
32
“Upon pooling 15 epidemiology studies of childhood
leukemia, the authors found evidence of increased risk at
the low(0 to ~5 mG), but upper-end magnetic field levels
(i.e., comparing fields 0 to 1 mG versus greater than 3 mG)
to which a small proportion of United States residents are
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 14 of 41
1
2
3
4
5
exposed. The authors estimated a relative risk (RR) of 1.7
(1.2 - 2.3) for exposures above 3 mG, and a population
attributable fraction of 3% (-2% - +8%) for exposures
above 0.5 mG.”
4.
Hatch E.E., Kleinerman R.A., Linet M.S., Tarone R.E., Kaune W.T.,
6
Auvinen A., et al. Do Confounding or Selection Factors of Residential
7
Wiring Codes and Magnetic Fields Distort Findings of Electromagnetic
8
Fields Studies?, Epidemiology 11: 189-98 (2000):
“In contrast with several previous studies, our recent large
case-control study found little association between
childhood acute lymphoblastic leukemia (ALL) and
electric-power-line wire codes.”
9
10
11
12
13
5.
Kleinerman R.A., Kaune W.T., Hatch E.E., Wacholder S., Linet M.S.,
14
Robison L.L., Niwa S., Tarone R.E., Are Children Living Near High-
15
Voltage Power Lines at Increased Risk of Acute Lymphoblastic
16
Leukemia?, American J. Epidemiology 151:512-5 (2000):
17
18
19
20
21
22
23
24
25
“The authors analyzed distance to transmission and threephase primary distribution lines within 40 m of homes and
created an exposure index of distance and strength of
multiple power lines (408 case-control pairs). Neither
distance nor exposure index was related to risk of
childhood acute lymphoblastic leukemia, although both
were associated with in-home magnetic field
measurements. Residence near high-voltage lines did not
increase risk.”
26
6.
Skinner J., Mee TJ., Blackwell R.P., Maslanyj M.P., Simpson J., Allen
27
S.G., Day N.E., Cheng K.K., Gilman E., Williams D., Cartwright R., Craft
28
A., Birch J.M., Eden A.B., McKinney P.A., Deacon 1., Peto J., et al.
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 15 of 41
1
Exposure to Power Frequency Electric Fields and the Risk of Childhood
2
Cancer in the UK. British J. Cancer 87: 1257-66 (2002):
3
4
5
6
7
8
9
“The United Kingdom Childhood Cancer Study, a
population-based case-control study covering the whole of
Great Britain, incorporated a pilot study measuring
electric fields. [….] With exposure modeled as a continuous
variable, odds ratios for an increase in the principal metric
of 10 V/m were close to unity for all disease categories,
never differing significantly from one.”
10
7.
UK Childhood Cancer Study Investigators. Childhood Cancer and
11
Residential Proximity to Power Lines. British J. Cancer. 83:1573-1580
12
(2000):
13
14
15
16
17
“Our results provide no evidence that proximity to
electricity supply equipment or exposure to magnetic fields
associated with such equipment is associated with an
increased risk for the development of childhood leukemia
nor any other childhood cancer.”
18
8.
Kabuto M., Nitta H., Yamamoto S., et al. Childhood leukemia and
19
magnetic fields in Japan: a case-control study of childhood leukemia and
20
residential power-frequency magnetic fields in Japan. International
21
Journal of Cancer. 119:643-50 (2006):
22
23
24
25
“Even an analysis in which selection bias was maximized
did not fully explain the association. Most of the leukemia
cases in the highest exposure category had MF levels far
above 0.4 μT.”
26
9.
Draper G., Vincent T., Kroll M.E., Swanson J., Childhood cancer in
27
relation to distance from high voltage power lines in England and Wales: a
28
case-control study. British Medical Journal 330:1290-.
29
doi:10.1136/bmj.330.7503.1290 (2005):
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 16 of 41
“There is an association between childhood leukemia and
proximity of home address at birth to high voltage power
lines, and the apparent risk extends to a greater distance
than would have been expected from previous studies.
About 4% of children in England and Wales live within 600
m of high voltage lines at birth. If the association is causal,
about 1% of childhood leukemia in England and Wales
would be attributable to these lines, though this estimate
has considerable statistical uncertainty. There is no
accepted biological mechanism to explain the
epidemiological results; indeed, the relation may be due to
chance or confounding.”
1
2
3
4
5
6
7
8
9
10
11
12
13
10.
Kheifets L., Afifi A.A., Shimkhada R., Public health impact of extremely
14
low-frequency electromagnetic fields. Environmental Health Perspectives.
15
114: 1532-7 (2006):
16
17
18
19
20
“The fraction of childhood leukemia cases possibly
attributable to ELF exposure across the globe appears to
be small. There remain, however, a number of uncertainties
in these attributable fraction estimates, particularly in the
exposure distributions.”
21
11.
Elwood J.M., 2006. Childhood leukemia and residential magnetic fields:
22
are pooled [epidemiological] analyses more valid than the original
23
studies? Bioelectromagnetics. 27:112-8 (2006):
24
25
26
27
28
29
30
31
“Recent studies, using the exposure methods and the cut-off
levels set a priori, each concluded that there was little
evidence of any association. The pooled analyses, using
different exposure measures and different cut-offs,
conclude that an association exists at high exposure levels.
It is not clear if the results of the pooled analysis are more
valid than those of the recent major studies, although this
has been often assumed in influential reviews.”
32
Q8.
Why are there differences among the various reviews and studies?
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 17 of 41
1
A8.
There are several possible reasons for the differences among the various reviews
2
and studies. Some scientists put more emphasis on the statistical associations
3
from epidemiology, while others place weight on the negative laboratory studies,
4
i.e., animal and test tube experiments that have been unable to identify an EMF
5
mechanism, or a specific health problem. The absence of support from such
6
laboratory studies causes many scientists to conclude that the statistical
7
epidemiological links are due to unmeasured confounding factors. Others believe
8
in the importance of observational epidemiology and hence give more credence to
9
such studies, because extrapolations from animal species or from laboratory test-
10
tube systems need not be made.
11
12
Q9.
13
14
In your opinion, do the epidemiological studies support a casual link between
EMF exposure and the potential for adverse health effects?
A9.
Over the past two and a half decades, some epidemiology studies have reported
15
weak associations between surrogate markers of power-line magnetic field
16
exposure and risk of childhood leukemia. Because of these studies, the
17
International Agency for Research on Cancer (IARC) classified power-line EMF
18
as a “possible” carcinogen in 2002. A recent study in Japan and a recent study in
19
the UK reported associations of childhood leukemia with distance from power
20
lines, the latter at surprisingly large distances, where EMF levels from the lines
21
were essentially at background. Even though epidemiology continues to provide
22
the strongest suggestions of health effects, the results among the studies remain
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 18 of 41
1
weak and inconsistent, and poorly linked to actual EMF exposures. In addition,
2
these statistical, correlative results are not able to establish causation. That is,
3
while a laboratory scientist can precisely set exposure conditions, randomly
4
allocate groups to be exposed or non-exposed, do careful pathology on the
5
outcome, and can read the results blindly (i.e., without knowing the exposure
6
history), epidemiology is an observational science and cannot apply such rigorous
7
scientific methods. Other problems cloud the interpretation of the epidemiology.
8
None of the exposure assessments used in epidemiological studies are based on
9
mechanisms of interaction, or on possible EMF regulatory policies. An
10
epidemiologic study that reports “statistically significant” associations is only
11
testing that significance against the role of random chance. If other sources of
12
uncertainty in epidemiologic studies were to be quantitatively included in the
13
confidence interval (e.g., confounding factors, measurement error, selection bias,
14
misclassification), the error bars would be much broader and would likely overlap
15
a null outcome (i.e., “no association”). Reviews of EMF epidemiology emphasize
16
this point, namely, that the error bars in reported results reflect no other sources of
17
uncertainty aside from random error (i.e., population size), and consequently the
18
results are less indicative of an association than one might think. The error bars
19
include only chance, and not the possible roles of confounding, selection bias, and
20
misclassification bias.
21
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 19 of 41
1
Q10.
2
3
What conclusions have been drawn from the laboratory and animal studies of
EMF biological effects?
A10.
Not only is the interpretation of power-line EMF epidemiology clouded and
4
uncertain, but also, other lines of scientific evidence weigh against assigning a
5
causal basis to the associations. To date, there is no established laboratory
6
bioassay or animal model by which power line EMF has been shown to initiate or
7
accelerate biological changes related to cancer risk. Although lifetime exposure
8
to high levels of 60-Hz magnetic fields has been tested in many animal studies,
9
the results have failed to show that 60-Hz magnetic fields can initiate or
10
exacerbate any disease or pre-disease condition, even in genetically modified and
11
susceptible animals. Even though it is now a 7-year-old result, the National
12
Toxicology Program (NTP) testing of 60-Hz EMF, listed below, remains the
13
largest laboratory study, because its scope and number of animals tested is
14
unlikely to ever be duplicated. The NTP study found no cancer risks at elevated
15
EMF exposures (10,000 to 20,000 mG). Such animal testing is the foundation (or
16
“gold standard”) for probing health effects, because it is through such exhaustive
17
studies that regulators can determine what (if any) aspect of an exposure (e.g.,
18
chemicals or “EMF”) should potentially be regulated. This means that scientists
19
have not been able to identify what aspect of EMF (if any) is the one we should
20
potentially avoid. That is, even if we were to accept the possibility of an adverse
21
health effect, we have no evidence by which to decide whether it is due
22
specifically to the frequency of oscillation, the electric fields, the magnetic fields,
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 20 of 41
1
continuous exposure, intermittent exposure, peak fields, or transients in EMF. In
2
spite of many years of diligent work, no firm evidence of adverse EMF effects has
3
been found in the laboratory for any of these measures of EMF exposure.
4
5
Q11.
What is the present status of expert opinion on EMF health effects?
6
A11.
Research to date, reporting extensive efforts by scientists worldwide, has not
7
identified plausible mechanisms by which public exposure to power-line EMF can
8
cause adverse health effects. EMF interactions with biological systems have been
9
analyzed carefully in light of the biophysics of electromagnetic field interactions
10
with matter. The applicability of fundamental physics to all systems, and to
11
biology in particular, permits evaluation of the interaction of EMF with ions,
12
molecules, cells, and organisms. The conclusions are that the effects of typical
13
power-line EMF are not detectable above the many sources of disturbance
14
(electrical and other “noise”) in living systems. Examination of all possible
15
aspects of EMF exposure have revealed no firm basis on which to attribute a
16
potential for adverse effects specifically to, for example, electric fields or to
17
magnetic fields, to the fundamental frequency or to harmonics, to continuous
18
exposure or to intermittent exposure, to time-average fields or to peak fields, to
19
constant amplitude EMF or to transients in EMF. A new mechanism being
20
evaluated is “contact currents,” which, if true, would mean that the
21
epidemiological associations arise through factors that are not EMF at all, but
22
happen to vary with EMF. Over the years, many ideas have been proposed in this
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 21 of 41
1
area, and many analyses have been performed, but diligent attention by scientists
2
has not yielded identified aspects, levels, or durations of EMF exposure that lead
3
to increased cancer risk. Without any understanding of mechanism, it remains
4
unknown as to what, if any, aspect of EMF exposure should be controlled.
5
At this point in time, a large volume of research and analysis on the question of
6
EMF health effects has been generated, representing the accumulation of many
7
years of laboratory work and many years of human experience with EMF. The
8
scientific data on EMF and health have been assembled and reviewed by many
9
independent scientific consensus groups of research and public-health experts.
10
These groups and agencies include the World Health Organization, the National
11
Radiation Protection Board (UK), the National Academy of Sciences, the
12
American Medical Association, the American Physical Society (the professional
13
society for American physicists), the American Cancer Society, the Swedish
14
National Health and Welfare Board, and others. These “blue-ribbon” panels do
15
not conclude that EMFs from electric-power transmission lines are unsafe for
16
nearby residents and public. The reports of these groups are voluminous,
17
thorough, and even-handed. Some of the conclusions are given below (websites
18
last accessed June, 2007).
19
20
American Cancer Society (ACS), “What Are the Risk Factors for Acute Myeloid
21
Leukemia (AML)?” (2006) Available on the Internet at:
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 22 of 41
1
http://www.cancer.org/docroot/CRI/content/CRI_2_4_2x_What_Are_the_Risk_F
2
actors_for_Acute_Myeloid_Leukemia_AML.asp?sitearea
3
4
5
6
7
8
9
10
11
12
13
14
15
“There is some question about electromagnetic field (EMF)
exposure (such as that occurring near very high-voltage
power lines) as a potential risk factor for developing
leukemia. Most studies published so far suggest either no
increased risk or a very slightly increased risk. Clearly,
most cases of leukemia are not related to EMF exposure.”
http://www.cancer.org/docroot/NWS/content/NWS_2_1x_The_Environment_and
_Cancer_Risk.asp .
“Unproven Risks: Electromagnetic radiation at
frequencies below ionizing radiation and UV levels has not
been proven to cause cancer. Some studies suggest it is
associated with cancer, but most of the now extensive
research in this area does not.”
16
American Conference of Governmental Industrial Hygienists (ACGIH),
17
“Threshold Limit Values (TLVs) and Biological Exposure Indices (BEls),”
18
ACGIH 6500 Glenway Ave., Cincinnati, OH. (2006), p. 154:
19
20
21
22
23
“It is recommended that, lacking specific information on
electromagnetic interference from the manufacturer, the
exposure of persons wearing cardiac pacemakers or
similar medical electronic devices be maintained at or
below 0.1 mT (1,000 mG) at power frequencies (60 Hz).”
24
European Union (EU), “Scientific Committee on Toxicity, Ecotoxicity and the
25
Environment (CSTEE): Opinion on Possible Effects of Electromagnetic Fields
26
(EMF), Radio Frequency Fields (RF) and Microwave Radiation on Human
27
Health,” European Commission Directorate-General: Health and Consumer
28
Protection (2001), Brussels, C2/JCD/csteeop/EMF /RFF30 1 0200 1/D(O 1 ).
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 23 of 41
1
Available at:
2
http://ec.europa.eu/health/ph_risk/committees/sct/documents/out128_en.pdf.
3
4
5
6
7
8
9
10
11
12
13
14
15
“Combined analyses of the epidemiological studies on the
association between exposure to ELF and childhood
leukemia have strengthened the evidence of an association.
However, given some inconsistencies in exposure
measurements and the absence of other criteria commonly
used in assessing causality (particularly a plausible
explanation of underlying biological mechanisms, see
above), the association does not meet adequate criteria for
being considered causal. Thus the overall evidence for
50/60 Hz magnetic fields to produce childhood leukemia
must be regarded as being limited. There is no convincing
suggestion of any other carcinogenic effect of ELF on
either children or adults.” (p. 10)
16
Institute of Electrical & Electronics Engineers (IEEE), “C95.6-2002 IEEE
17
Standard for Safety Levels with Respect to Human Exposure to Electromagnetic
18
Fields 0 to 3 kHz. Prepared by Subcommittee 3, Safety Levels with Respect to
19
Human Exposure, 0 to 3 kHz, of the International Committee on Electromagnetic
20
Safety, Standards Coordinating Committee 28.” IEEE, Inc., Three Park Avenue,
21
New York, NY 10016-5997, USA. ISBN 0-7381-3389-2 (2002):
22
23
24
25
“Protection is to be afforded to individuals in the general
population by limiting maximum permissible exposure
(MPE) to magnetic field levels of 9,040 mG at 60-Hz
power-line frequencies.”
26
International Agency for Research on Cancer (IARC), “Non-Ionizing Radiation,
27
Part 1: Static and Extremely Low-Frequency (ELF) Electric and Magnetic Fields.
28
IARC Monographs on the Evaluation of Carcinogenic Risks in Humans.” 80: 1-
29
429 (2002):
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 24 of 41
1
2
3
4
5
6
7
8
9
“The association between childhood leukemia and high
levels of magnetic fields is unlikely to be due to chance, but
it may be affected by bias. In particular, selection bias may
account for part of the association.” (p. 332) [Thus] there
is limited evidence in humans for the carcinogenicity of
extremely low-frequency magnetic fields in relation to
childhood leukemia. There is inadequate evidence in
humans for the carcinogenicity of extremely low-frequency
magnetic fields in relation to all other cancers.” (p. 338)
10
International Commission on Non-Ionizing Radiation Protection (ICNIRP).
11
“ICNIRP Statement Related to the Use of Security and Similar Devices Utilizing
12
Electromagnetic Fields.” (2004) Available at:
13
http://www.icnirp.de/documents/EASD.pdf .
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
“The epidemiological studies conducted on possible health
effects of EMF have improved over time in sophistication of
exposure assessment and in methodology. Several of the
recent studies on childhood leukemia and occupational
exposures in relation to adult cancer are close to the limit
of what can be achieved by epidemiology, in terms of size
of study and methodological rigor, using presently
available measurement methods. In the absence of
evidence from cellular or animal studies, and given the
methodological uncertainties and in many cases
inconsistencies of the existing epidemiological literature,
there is no chronic disease outcome for which an
etiological relation to EMF exposure can be regarded as
established.” (page 193, “Low Frequency EMF”) [ICNIRP
Reference Levels protect the general public from
established health effects due to EMF exposure. The
Reference Levels for 60-Hz EMF exposure are: 4.16 kV/m
and 833 mG.]
32
Minnesota Department of Health (MDH) “Electric and Magnetic Fields (EMF)
33
What conclusions can be made about EMF?” March 2007 Available at:
34
http://www.health.state.mn.us/divs/eh/radiation/emf/index.html.
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 25 of 41
1
2
3
4
5
6
7
8
9
10
11
“The Minnesota Department of Health has concluded that
the current body of evidence is insufficient to establish a
cause and effect relationship between EMF and health.
While some epidemiological studies have reported a weak
association between leukemia with increasing exposure to
magnetic fields, other studies have reported no association.
Epidemiological studies alone are considered insufficient
for concluding that a cause and effect relationship exists,
and must be supplemented by data from laboratory studies.
Existing laboratory studies have not substantiated this
relationship (even at high exposure levels).”
12
National Academy of Sciences (NAS); National Research Council (NRC),
13
“Research on Power-Frequency Fields Completed Under the Energy Policy Act
14
of 1992. Final Report.” National Academy of Sciences Evaluation of the EMF
15
RAPID Program, National Research Council, National Academy Press, June
16
1999, l07 pp. Available at: http://www.nap.edu/catalog/9587.html.
“Results of the EMF-RAPID program do not support the
contention that the use of electricity poses a major
unrecognized public-health danger.”
17
18
19
20
National Radiation Protection Board (NRPB) of the United Kingdom (UK),
21
“Review of the Scientific Evidence for Limiting Exposure to Electromagnetic
22
Fields (0 to 300 GHz). Volume 3, No .3” (2004) Available at:
23
http://www.hpa.org.uk/radiation/publications/documents_of_nrpb/pdfs/doc_15_3.
24
pdf.
25
26
27
28
29
30
31
32
“The epidemiological evidence indicates that exposure to
power frequency magnetic fields above 0.4 μT [4 mG] is
associated with a small absolute raised risk of leukemia in
children (an approximate doubling of the relative risk).
However, the evidence is not strong enough to justify a firm
conclusion that such fields cause leukemia in children.
There is little evidence to suggest that the risk of childhood
leukemia might be increased by exposure to ELF magnetic
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 26 of 41
1
2
3
4
5
6
7
8
9
fields of time-weighted average magnetic flux density below
0.4 μT [4 mG] or that raised cancer risks of other types in
children and adults might arise as a result of exposure to
ELF magnetic fields. Information specifically on electric
fields is more sparse.” … “The results of epidemiological
studies, taken individually or as collectively reviewed by
expert groups, cannot be used as a basis for the derivation
of quantitative restrictions on exposure to EMFs.” (page
38)
10
Netherlands Health Council, “Exposure to Electromagnetic Fields (0 Hz - 10
11
MHz).” The Minister of Housing, Spatial Planning and the Environment, Report
12
Number:
13
U-629/EvRJRA/559-C, The Hague, the Netherlands, 7 March 2000, Available at:
14
http://www.gr.nl/pdf.php?ID=25.
15
16
17
18
19
20
21
22
23
24
25
“The results of epidemiological studies [of EM field
exposure], both in children and adults, do not allow the
establishment of a causal relationship between the
observed [diseases] and exposure to ELF EM fields or any
other factor. Also the large body of experimental research
has failed to produce any evidence of a causal relationship
between exposure to ELF EM fields and the occurrence of
any form of cancer.” (p. 15) “Effects of ELF EM fields in
the general population [can be avoided] by limiting wholebody exposure to 1,200 mG at 50 Hz power-line
frequencies.” (Table 2.3.3, p. 37)
26
World Health Organization (WHO), “Electromagnetic Fields and Public Health:
27
Extremely Low Frequency Fields and Cancer. Fact Sheet No. 263, October
28
2001.” Available at:
29
http://www.who.int/docstore/peh-emf/publications/facts_press/efact/efs263.html.
30
31
32
33
“While the classification of ELF magnetic fields as possibly
carcinogenic to humans [by IARC] has been made, it
remains possible that there are other explanations for the
observed association between exposure to ELF magnetic
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 27 of 41
1
2
3
4
fields and childhood leukemia. In particular, issues of
selection bias in the epidemiological studies and exposure
to other field types deserve to be rigorously examined and
will likely require new studies.” (Fact Sheet #263)
5
Just this year (June 2007) the WHO issued an additional voluminous report on
6
EMF, the “Environmental Health Criteria No. 238 on Extremely Low Frequency
7
Fields.” This 446-page document reviews all aspects of potential health effects
8
of “extremely low-frequency electric and magnetic fields,” which include power-
9
line fields at 60 Hz. For all disease outcomes considered, aside from childhood
10
leukemia, the WHO judges the evidence that EMF causes health effects as
11
“inadequate.” For childhood leukemia, WHO concludes that “on balance, the
12
evidence is not strong enough to be considered causal” and that “a causal
13
relationship between magnetic field exposure and childhood leukemia has not
14
been established,” but that the concern does merit additional research attention:
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
“Scientific evidence suggesting that everyday, chronic lowintensity power-frequency magnetic field exposure poses a
health risk is based on epidemiological studies
demonstrating a consistent pattern of increased risk for
childhood leukaemia. Uncertainties in the hazard
assessment include the role that control selection bias and
exposure misclassification might have on the observed
relationship between magnetic fields and childhood
leukaemia. In addition, virtually all of the laboratory
evidence and the mechanistic evidence fail to support a
relationship between low-level ELF magnetic fields and
changes in biological function or disease status. Thus, on
balance, the evidence is not strong enough to be considered
causal, but sufficiently strong to remain a concern.
Although a causal relationship between magnetic field
exposure and childhood leukaemia has not been
established, the possible public health impact has been
calculated assuming causality in order to provide a
potentially useful input into policy. However, these
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 28 of 41
1
2
3
4
5
6
7
8
9
calculations are highly dependent on the exposure
distributions and other assumptions, and are therefore very
imprecise. Assuming that the association is causal, the
number of cases of childhood leukaemia worldwide that
might be attributable to exposure can be estimated to [ …
]represent 0.2 to 4.9% of the total annual incidence of
leukaemia cases. Thus, in a global context, the impact on
public health, if any, would be limited and uncertain.” (p.
11-12 of “Summary” section)
10
http://www.who.int/peh-emf/publications/elf_ehc/en/index.html.
11
12
Q12.
Are you aware of whether any state, national, or international health organizations
13
or regulatory bodies have adopted or recommended guidelines that limit EMF
14
exposure fields from electric power lines or other sources?
15
A12.
The United States has no federal standards limiting occupational or residential
16
exposure to 60-Hz EMF. The first of the two tables below shows guidelines
17
suggested by national and world health organizations. The second table shows
18
guidelines that have been adopted by various states in the U.S. The first table
19
shows the public-health-based levels, which are intended to be protective against
20
adverse health effects but should not be viewed as demarcation lines between safe
21
and dangerous levels of EMF. The latter (state) guidelines have been designed to
22
maintain the status quo of EMF on and near transmission-line right-of-ways
23
(ROWs), and are not health-based.
24
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 29 of 41
1
60-Hz EMF Guidelines Established by Health & Safety Organizations
Organization
Magnetic Field
Electric Field
American Conference of Governmental and Industrial
Hygienists (ACGIH) (occupational)
10,000 mG (a)
25 kV/m (a)
1,000 mG (b)
1 kV/m (b)
International Commission on Non-Ionizing Radiation
Protection (ICNIRP) (general public, continuous
exposure)
833 mG
4.2 kV/m
Non-Ionizing Radiation (NIR) Committee of the
American Industrial Hygiene Assoc. (AIHA) endorsed
(in 2003) ICNIRP’s occupational EMF levels for workers
4,170 mG
8.3 kV/m
Institute of Electrical and Electronics Engineers (IEEE)
Standard C95.6 (general public, continuous exposure)
9,040 mG
5.0 kV/m
U.K., National Radiological Protection Board (NRPB)
[now Health Protection Agency (HPA)]
833 mG
4.2 kV/m
1,000 mG
4.2 kV/m
Australian Radiation Protection and Nuclear Safety
Agency (ARPANSA), Draft Standard, Dec. 2006 (c)
Comparison to steady (DC) EMF, encountered as EMF outside the 60-Hz frequency range:
Earth’s magnetic field and atmospheric electric fields,
steady levels, typical of environmental exposure (d)
Magnetic Resonance Imaging Scan, static magnetic
field intensity (c)
2
3
4
5
6
7
8
9
10
(a)
(b)
(c)
(d)
[550 mG]
[0.2 kV/m up
to > 12 kV/m]
[20,000,000 mG]
---
represents ACGIH guidelines for the general worker.
represents ACGIH guideline for workers with cardiac pacemakers.
http://www.arpansa.gov.au/pubs/comment/dr_elfstd.pdf.
These EMF are steady fields, and do not vary in time at the characteristic
60-cycles-per-second that power-line fields do. However, if a person
moves in the presence of these fields, the body experiences a time-varying
field.
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 30 of 41
1
State Transmission-Line 60-Hz EMF Standards and Guidelines
Electric Field
State / Line Voltage
69 – 230 kV
Florida
On ROW
Magnetic Field
Edge ROW
8.0 kV/m
c
10.0 kV/m
On
ROW
Edge ROW
150 mG
} 2.0 kV/m
f
200 mG, 250 mG
500 kV
Massachusetts
e
85 mG
Minnesota
8.0 kV/m
Montana
7.0 kV/m a
New Jersey
1.0 kV/m b
3.0 kV/m
New York c
11.8 kV/m
11.0 kV/m d
1.6 kV/m
200 mG
7.0 kV/m a
Oregon
2
3
4
5
6
7
8
9
10
11
12
13
14
15
9.0 kV/m
Key:
ROW = right of way; mG = milliGauss; kV/m = kilovolts per meter
Notes:
a
b
c
d
e
f
Maximum for highway crossings
May be waived by the landowner
Magnetic fields for winter-normal, maximum line load capacity
Maximum for private road crossings
500 kV double-circuit lines built on existing ROW’s
Includes the property boundary of a substation
Sources: “Questions and Answers About EMF.” National Institute of
Environmental Health Sciences and U.S. Department of Energy, 2002.
Florida, see: ftp://ftp.dep.state.fl.us/pub/siting/Rules/62-814-EMF.doc.
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 31 of 41
1
2
4.
Summary of the EMF Calculated for the Project
3
Q13.
How did you assess the EMF impact of the proposed Project?
4
A13.
I relied upon the EMF modeling performed for the Southern Loop Project by Mr.
5
Jeff Carrara, a Systems Engineer for VELCO.
6
7
Q14.
What information did you and Mr. Carrara exchange?
8
A14.
Mr. Carrara provided me information on the transmission line design, the type of
9
computer model he used, the input parameters and the results for electric and
10
magnetic fields as a function of distance from the lines and under various loading
11
assumptions.
12
13
Q15.
14
15
Are you comfortable that Mr. Carrara utilized an appropriate computer model and
input assumptions?
A15.
Yes. I reviewed all of his data and discussed the results with him. I am confident
16
that his EMF modeling results reflect accurate calculations of EMF along the
17
existing and future line corridors.
18
19
Q16.
Please summarize the results of the EMF calculations.
20
A16.
The following tables summarize some of Mr. Carrara’s results and compare the
21
EMF conditions, projected to 2017, for the existing line configuration versus the
22
EMF conditions for the proposed line configuration, at peak normal electric load
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 32 of 41
1
demand. The EMF predictions are given for existing versus proposed line
2
configurations and loadings for the calendar year 2010 and 2017. Separate tables
3
show the results for three general segments for the project, namely
4
Segment 1 – Coolidge substation in Cavendish, VT, towards the Newfane and
5
Vernon substations further south. This segment has one existing 345 kV
6
line in a 150-foot-wide ROW and has a new 345 kV line being added
7
which expands the ROW to 250-foot-wide.
8
Segment 2 – Newfane substation in Newfane, VT, towards the main north-south
9
corridor between Coolidge and Vernon substations. This segment today
10
has a single 46 kV line in a 150-foot-wide ROW (presently, tree clearing
11
only +/– 50 feet from the current line). New double circuit 345 kV
12
structures (with two new 345 kV lines) will be added, expanding the ROW
13
to 210-foot-wide.
14
Segment 3 – Vernon substation in Vernon, VT, towards the Newfane and
15
Coolidge substations further north. This segment has one existing 345 kV
16
line in a 150-foot-wide ROW and has a new 345 kV line being added
17
which expands the ROW to 250-foot-wide. The majority of this segment
18
is made up of H-Frame structures with a horizontal conductor
19
configuration which is the same as the first two segments. This H-Frame
20
configuration shall be referred to as sub-segment 3A. Several structures
21
north of the Vernon substation are built in a vertical conductor
22
configuration, the new line will also be vertical. This vertical
23
configuration shall be referred to as sub-segment 3B.
24
For modeling EMF, Mr. Carrara situated the lines within the ROW corridors at
25
the planned locations, and EMF levels were calculated from line voltages and
26
currents as a function of distance across the ROW. Results were tabulated for
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 33 of 41
1
locations along the ROW where the lines make their closest approach to ground
2
level. E Max, E Exist ROW and E Prop ROW designate the electric field maximum within
3
the ROW and at the edge of the existing and proposed ROW, respectively. The
4
units are kilovolts per meter (kV/m). Electric field levels do not change with
5
current loads. B Max, B Exist ROW and B Prop ROW designate the magnetic field
6
maximum within the ROW and at the edge of the existing and proposed ROW,
7
respectively. The units are milligauss (mG). Magnetic field values vary in direct
8
proportion to the electric current (power) carried by the lines, and calculations
9
were done for annual peak loads estimated for the 2010 and 2017 calendar years
10
(i.e., at 100% Winter Peak Loading). In 2017, electric-power contracts related to
11
the Highgate Converter (HG) may expire, putting more load on these lines; as
12
such, a “ 2017x ” year is also given in the tables below. While not attributed to
13
this Project, the loss of HG loading is only shown as a proposed loading. If the
14
values for EMF at the two ROW edges are different, the higher one is given. For
15
Segment 1, Segment 2, and Segment 3-A, one of the ROW edges is being
16
expanded (designated in the tables as “new N” = north, “new S” = south, or “new
17
W” = west, for the new ROW edges). The tables below compare existing and
18
proposed loading conditions at the western ROW edge as it exists today
19
(“E Exist ROW” and “B Exist ROW” columns) and as it is proposed (“E Prop ROW” and
20
“B Prop ROW” columns).
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 34 of 41
Segment 1, Coolidge to South (35.4 miles) (add new H-Frame west of existing H-Frame)
E Max
E Exist ROW
B Max
B Exist ROW
E Prop ROW ,
B Prop ROW ,
new W
new W
Condition
Year
(kV/m)
(mG)
(kV/m)
(kV/m)
(mG)
(mG)
Existing
Proposed
2010
6.7
1.6
0.14
185
42
7.9
2017
6.7
1.6
0.14
210
48
9.0
2010
6.8
6.5
1.6
111
96
21
2017
6.8
6.5
1.6
121
105
23
2017x
6.8
6.5
1.6
134
118
26
Existing ROW width is ± 75 ‘ from the existing structure. Proposed ROW (“Prop ROW”) moves
the west ROW edge 100 feet to the west.
Segment 2, Newfane to East (1 mile) (add new 345-kV double-circuit to north of 46 kV)
E Max
B Max
E Exist ROW ,
E Prop ROW ,
B Exist ROW ,
B Prop ROW ,
N & S edges
new N edge
N & S edges
new N edge
Condition
Year
(kV/m)
(kV/m)
(mG)
(mG)
(kV/m)
(mG)
Existing
Proposed
2010
0.34
0.05 & 0.04
0.02
6.3
0.8 & 0.6
0.3
2017
0.34
0.05 & 0.04
0.02
29
3.8 & 3.0
1.2
2010
8.5
8.3 & 0.33
0.25
75
68 & 2.8
9.8
2017
8.5
8.3 & 0.33
0.25
82
75 & 2.9
10.6
2017x
8.5
8.3 & 0.33
0.25
91
83 & 3.3
12.2
Existing ROW width is 150 feet (82’ south, 68’ north) from the existing structure. Proposed ROW
(“Prop ROW”) moves the north ROW edge 60 feet further to the north.
Segment 3-A, Vernon to North (15.4 miles) (add new H-Frame west of existing H-Frame)
E Max
E Exist ROW
B Max
B Exist ROW
E Prop ROW ,
B Prop ROW ,
new W
new W
Condition
Year
(kV/m)
(mG)
(kV/m)
(kV/m)
(mG)
(mG)
2010
6.7
1.6
0.14
185
42
7.9
Existing
2017
6.7
1.6
0.14
210
48
9.0
2010
6.8
6.5
1.6
116
106
23
Proposed
2017
6.8
6.5
1.6
126
115
25
2017x
6.8
6.5
1.6
139
127
28
The Existing ROW width is ± 75 feet from the existing structure. The proposed ROW (“Prop
ROW”) moves the west ROW edge 100 feet to the west.
Segment 3-B, Vernon to North, Vertical Construction (1.0 mile) (add
new circuit on west side of towers with existing circuit on east side)
E Max
E Exist ROW
B Max
B Exist ROW
Condition
Year
(kV/m)
(kV/m)
(mG)
(mG)
2010
6.4
0.24
113
20
Existing
2017
6.4
0.24
129
22
2010
7.0
0.34
66
23
Proposed
2017
7.0
0.34
77
26
2017x
7.0
0.34
84
29
The Existing ROW width is ± 100 feet from the existing structure, and the ROW width
does not change.
1
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 35 of 41
1
Generally, the phasing of the 345-kV circuits is important for balancing the
2
impedance of the system, and hence, changing the phases of conductors may not
3
be possible for EMF mitigation. Because of this constraint, mitigation via phase
4
rotation is a feasible option only in Segments 2 and 3B. In Segment 2, the base
5
configuration (initial configuration) gives the best mitigation of magnetic fields at
6
the edge of the ROW, and this is what is shown in the table above.
7
8
Q17.
Please explain what conclusions on EMF levels you draw from these results.
9
A17.
Several conclusions about EMF impact can be drawn from these results. First, in
10
comparison to the international, national, and state standards and guidelines listed
11
earlier, the EMF levels (both the maximum levels and at the ROW edge) are
12
considerably below what is permissible within the guidelines, for public locations.
13
Moreover, in terms of the magnetic fields (the component of EMF that has been
14
subject to the greatest scrutiny), the maximum levels caused by the Project are
15
quite modest.
16
17
Q18.
18
19
What are your conclusions with regard to impact of the Project EMF’s on public
health?
A18.
On the basis of the EMF levels at issue and on the basis of the scientific literature
20
and public health guidance available in this area, I conclude that no public health
21
impact will result from the EMF’s associated with operation of the lines proposed
22
in this Project.
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 36 of 41
1
2
5.
Summary of Analysis and Conclusions
3
Q19.
What is your summary of the current status of the science of EMF health effects?
4
A19.
Thousands of studies have now examined the hypothesis that power-line EMF
5
exposure can lead to biological effects, and potentially, adverse health impacts.
6
Out of this vast number, some studies have reported results that could be
7
interpreted as suggestive of power-line EMF being hazardous to human health.
8
However, it has not been possible to determine if these results truly reflect a
9
consistent and causal role for EMF in the health endpoints studied or whether they
10
represent statistical fluctuations and/or non-causal factors, such as might be
11
expected in any series of observed correlations. For those biological effects that
12
have been occasionally reported in laboratory studies as showing EMF to modify
13
the operation of living systems, independent investigators have tried, but failed, to
14
replicate the results. This lack of replication supports the conclusion that power-
15
line EMF at levels encountered in the general environment is not hazardous, and
16
my overall summary is that evidence for EMF harming health is weak and
17
inconsistent. Even more scarce is evidence as to what specific aspects or types of
18
EMF exposure, if any, are to be implicated in the hypothetical health-risks. No
19
biological process has been established whereby environmental levels of power-
20
line EMF can initiate a chain of biological events that may plausibly lead to
21
adverse effects on health. As a consequence, research to date cannot give policy-
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 37 of 41
1
makers confidence as to the extent to which, or if at all, societal resources should
2
be expended to reduce power-line EMF exposures.
3
4
Q20.
5
6
Some researchers have proposed that policy makers adopt strategies of “prudent
avoidance” of EMF exposure. What is your opinion of such proposals?
A20.
The Vermont Department of Health (“VDH”) recommends a policy of prudent
7
avoidance, which strives to “strike a reasonable balance between avoiding
8
potential harm and the attendant costs and risks.” The VDH recommends that
9
“utilities should take steps to lower magnetic field exposure in cases when this
10
can be done at a modest cost,” and there is no harm in such a strategy. There is
11
unlikely to be a significant waste of resources in recommending that utilities
12
consider no-cost or low-cost EMF mitigation measures.
13
14
The VDH policy assumes that the intensity of time-averaged, 60-Hz magnetic
15
fields should be the focus of “modest cost” mitigation. It should be recognized,
16
however, that the scientific basis for this choice is weak, and many other specific
17
aspects of the “EMF environment” have been proposed as possible agents of
18
biological activity.
19
If an unqualified strategy of “prudent avoidance” is to be implemented, then there
20
is a problem in specifying which of the many EMF parameters should be
21
“prudently avoided” or “pre-cautiously regulated,” because scientists have not
22
been able to identify the potentially “harmful element” of EMF. The many
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 38 of 41
1
characteristics of EMF include: (1) electric field intensity, (2) magnetic field
2
intensity, (3) fields with an intensity within certain “windows” of possible
3
amplitudes, (4) peak magnetic fields, (5) 60-Hz magnetic fields with time-varying
4
frequency, (6) magnetic fields at harmonic frequencies (180 Hz, 300 Hz, etc.), (7)
5
only the power-line magnetic field that is parallel to the earth’s static magnetic
6
field, (8) only magnetic fields of non-steady, or “intermittent” amplitude, (9)
7
magnetic fields with circular polarization, i.e., rotating magnetic fields), (10)
8
magnetic fields of frequencies in “resonance” with certain biological ions such as
9
calcium (Ca ++), sodium (Na +), or potassium (K+), and (11) night-time magnetic
10
fields that may interfere with melatonin secretion. 7
11
12
None of these many aspects of EMF, however, has been convincingly shown to
13
be a likely risk factor, nor has any aspect been convincingly “ruled out” as
14
irrelevant to potential risk. Thus, the majority of EMF researchers would say that
15
extensive expenditures on EMF mitigation cannot be well-justified or guided by
16
science. Consequently, there is no solid basis for committing significant
17
resources to the development or implementation of avoidance strategies, when it
18
is not known what is to be avoided.
19
7
Valberg, P.A. Designing EMF Experiments: What is Required to Characterize “EMF” Exposure.
Bioelectromagnetics 16:396-401 (1995).
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 39 of 41
1
The state of EMF science suggests that the anxiety, time, energy, and money that
2
might be spent mitigating power-line EMF would likely provide greater health
3
benefit if it were expended on non-EMF health concerns. Other health-
4
improvement activities that are much more likely to produce a health benefit
5
include improved home safety, improved vehicle safety, improved prenatal care,
6
better nutrition, regular exercise programs, more frequent health checkups,
7
encouragement of smoking cessation, drinking in moderation, weight reduction,
8
blood pressure reduction, cholesterol reduction, and so forth.
9
Policymakers also need to consider that measures taken to reduce a hypothetical
10
risk may lead to an increase in other, real risks. For example, EMF from a
11
transmission line can be reduced by moving the phase conductors closer together,
12
but I understand this increases the risk of failure by flashover and can make the
13
tasks of electric-utility maintenance workers more hazardous. Likewise,
14
underground lines may reduce EMF in some areas, but this mitigation of
15
hypothetical risk needs to be weighed against adverse ecological impacts (damage
16
done to wetlands and wildlife habitat by the excavation necessary for
17
underground lines) and risks of longer outages in the case of failure. In the final
18
analysis, no human endeavor is without risk. Regardless of how many times one
19
finds a safe outcome for any phenomenon, one cannot guarantee that the next
20
investigation will not yield an adverse effect. This is an example of the fact that it
21
is impossible to prove a negative. Even though science can never provide proof
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 40 of 41
1
that powerline EMF carry zero risk to human health, it is my belief that the EMF
2
produced as a result of this Project will not have adverse public health effects.
3
4
Q21.
Did you consider possible effects of the EMF from these power-lines on the
5
proper operation of personal medical devices such as cardiac pacemakers and
6
insulin pumps?
7
A21.
Yes, in connection with my testimony on VELCO’s Northwest Vermont
8
Reliability Project (PSB Docket No. 6860), I reviewed available data on whether
9
power-line EMF might interfere with the electronics of life-sustaining medical
10
devices. I summarized my findings in a report entitled “Update on Scientific
11
Research Regarding Potential Health Effects of Power-Line Electric and
12
Magnetic Fields (EMF) (Sept. 2007)” and have attached the report to my
13
testimony as Exhibit Petitioners PAV-3.
14
15
Q22.
On what sources of information did you rely?
16
A22.
First, I identified and analyzed key research and review articles on the topic of
17
possible medical-device interference using the National Library of Medicine’s
18
“PubMed” bibliographic database of medical literature, containing over 14
19
million citations from approximately 4,600 biomedical and life science journals. I
20
also searched within the Food and Drug Administration (FDA) records at the
21
Center for Devices and Radiological Health, which maintains the Manufacturer
22
and User Facility Device Experience (MAUDE) database, a searchable, online,
Southern Loop Project, PSB Docket No. _____
Prefiled Testimony of Peter Alexis Valberg, Ph.D.
November 8, 2007
Page 41 of 41
1
post-market surveillance record of all reported adverse events involving
2
malfunctioning medical devices.
3
4
6.
Conclusion
5
Q23.
What were the conclusions of your analysis?
6
A23.
Although science cannot prove a negative, e.g., “nonexistence of medical-device
7
disruption,” research and clinical studies of conditions under which electrical
8
interference with medical-devices might occur did not point to power-line EMF as
9
a source. In spite of many nationwide electric-power transmission lines operating
10
in the proximity of people throughout the US, my review did not identify any
11
FDA-issued safety alerts, public health advisories, or medical case reports where
12
power-frequency EMF caused malfunction of medical devices.
13
14
Q24.
Does this conclude your testimony?
15
A24.
Yes, it does.