Letter from Dr. De-Kun Li, MD, PhD, MPH
Kaiser Permanente Division of Research 2000 Broadway Oakland,
CA 94612
Dear Ms. Martin:
Thank you for inviting me to provide my professional opinions on the
SmartMeter safety issue. I will address two questions raised in the attached
letter. But first, here is some background information:
1. Currently there are no national or international “standards” for safety
levels of radiofrequency (a range of 3 kHz to 300 GHz) devices. What FCC
is currently using are “guidelines” which have much lower certainty than a
“standard”. One can go to many governmental agencies’ websites like
NIOSH, EPA, FDA, etc. to verify this. Therefore, for anyone to claim that
they meet “FCC” standards gives a false impression of safety certainty
compared to “guidelines” which implies that a lot is “unknown.”
2. The current FCC “guideline” was adopted by FCC based on EPA’s
recommendation in 1996. EPA made the recommendation “with certain
reservation”. There was a letter by Norbert Hankin, Center for Science and
Risk Assessment, Radiation Protection Division at EPA describing the
current FCC guidelines (The letter can be found through a Google search).
According to Hankin’s letter, the FCC current guidelines were solely based
on “thermal effect” of radiofrequency, a level at which radiofrequency can
cause heat injury. As we know, heat injury is not what the public is
concerned about regarding radiofrequency safety. Their concerns are about
cancer, miscarriages, birth defects, low semen quality, autoimmune disease,
etc. Hankin’s letter, specifically emphasized that the EPA recommended
guidelines that FCC is currently using do not apply to non-thermal effects or
mechanisms (e.g., cancer, birth defects, miscarriage, autoimmune diseases,
etc) which are the focus of the public’s concern. Hankin’s letter states
“Therefore, the generalization by many that the guidelines protect
human beings from harm by any or all mechanisms is not justified.”
3. In addition to being limited to only the thermal effect, the letter also states
that the current FCC guidelines recommended by EPA were only based on
experiments on animals in laboratories. Establishing firm safety standards
usually requires evidence from human studies such as epidemiological
studies. The current FCC guidelines were based on animal studies only, not
human data, which may explain why they are only considered as guidelines
rather than standards. Furthermore, the thermal effect, used to establish the
FCC guidelines, was based on acute thermal effect. It did not even deal with
chronic long-term intermittent effect. In fact, Hankin’s letter also states
“exposures that comply with the FCC’s guidelines generally have been
presented as “safe” by many of the RF system operators and service
providers who must comply with them, even though there is uncertainty
about possible risk from nonthermal, intermittent exposures that may
continues for years”.
4. Electromagnetic fields (EMFs) can come from sources with a spectrum of
frequencies. EMFs from electric power sources usually have a frequency
less than 1 kHz , while radiofrequency (RF) generated by SmartMeters are
reportedly in the range 900 MHz to 2.4 GHz. While overall research on the
EMF health effect remains limited, there are more reported studies
examining the EMF health effect in power line frequencies (< 1 kHz)
including some of my research1-3 than in RF. It is not clear at this moment
whether the findings on the EMF health effect at lower frequencies (i.e., < 1
kHz) can be applied to RF range. If the underlying mechanisms are similar,
the findings in lower frequency EMFs can then be applied to RF range for
SmartMeter. Many studies of power frequencies reported associations with
childhood leukemia, miscarriage, poor semen quality, autoimmune diseases
at a level much lower than those generating thermal damage as used by
5. Many chronic diseases that the public is concerned about (e.g., cancer)
have a long latency period and take decades to show symptoms. Most
wireless network and devices have only been used widely in the last 10 to 15
years. Therefore, many studies evaluating RF health effect related to cancer
risk previously, if they failed to identify an adverse health effect, are not
appropriate to be used as evidence to claim the safety of RF exposure since
the latency period has not been long enough to show the effect even if an
adverse association does indeed exist.
6. While the underlying mechanisms of the potential EMF health effect are
not totally understood at present, skeptics have been focused on the EMF
thermal effect, especially those who are NOT in the profession of
biomedical research, such as physicists. It is now known that EMFs can
interfere with the human body through multiple mechanisms. For example,
it has been demonstrated that communication between cells depends on
EMF signals, likely in a very low level. External EMFs could conceivably
interfere with normal cell communication, thus disrupting normal cell
differentiation and proliferation. Such disturbance could lead to miscarriage,
birth defects, and cancer.
To address the two questions raised in the letter:
1. Whether FCC standards for SmartMeter are sufficiently protective of
public health taking into account current exposure levels to radiofrequency
and electromagnetic fields. First, FCC currently has only “guidelines”, not
standards as explained above. Second, as described in the background
information above, the current FCC guidelines only deal with thermal effect,
which was also based on animal studies only. Meeting the current FCC
guidelines, in the best-case scenario, only means that one won’t have heat
damage from SmartMeter exposure. It says nothing about safety from the
risk of many chronic diseases that the public is most concerned about such
as cancer, miscarriage, birth defects, semen quality, autoimmune diseases,
etc. Therefore, when it comes to non-thermal effects of RF, which is the
most relevant effect for public concerns, FCC guidelines are irrelevant and
can not be used for any claims of SmartMeter safety unless we are
addressing heat damage.
2. Whether additional technology-specific standards are needed for
SmartMeter and other devices that are commonly found in and around
homes, to ensure adequate protection from adverse health effects. Safety
standards for RF exposure related to non-thermal effects are urgently needed
to protect the public from potential adverse health effects from RF exposure
that are increasingly prevalent in our daily life due to installation of everpowerful
wireless networks and devices like SmartMeter. Unfortunately
scientific research is still lacking in this area and some endpoints like cancer
take decades to study. The safety standards are not likely to be available
anytime soon. The bottom line is that the safety level for RF exposure
related to non-thermal effect is unknown at present and whoever claims that
their device is safe regarding non-thermal effect is either ignorant or
In summary, we do not currently have scientific data to determine where the
safe RF exposure level is regarding the non-thermal effect. Therefore, it
should be recognized that we are dealing with uncertainty now and most
likely for the foreseeable future. The question for governmental agencies,
especially those concerned with public health and safety, is that given the
uncertainty, should we err on the side of safety and take the precautionary
avoidance measures? Unknown does not mean safe. There are two unique
features regarding SmartMeter exposure. First, because of mandatory
installation, it is a universal exposure. Virtually every household is exposed.
Second, it is an involuntary exposure. The public that are exposed to
SmartMeters do not have any input in deciding whether they would like to
have the SmartMeter installed. The installation is imposed upon the public.
Governmental agencies for protecting public health and safety should be
much more vigilant towards involuntary environmental exposures because
governmental agencies are the only defense against such involuntary
exposure. Given the uncertainty of the SmartMeter safety, one rational first
step of public policy could be to require household consent before
installation of SmartMeters. Finally, because of the nature of universal
exposure, many susceptible and vulnerable populations including pregnant
women and young children are unknowingly exposed 24 hours a day, 7 days
a week. Usually, the threshold of harmful level is much lower for
susceptible populations.
1. Li DK, Odouli R, Wi S et al. A population-based prospective cohort
study of personal exposure to magnetic fields during pregnancy and the risk
of miscarriage. Epidemiology 2002;13(1):9-20.
2. Li DK, Yan B, Li Z et al. Exposure to magnetic fields and the risk of
poor sperm quality. Reprod Toxicol 2010;29(1):86-92.
3. Li DK, Checkoway H, Mueller BA. Electric blanket use during
pregnancy in relation to the risk of congenital urinary tract anomalies among
women with a history of subfertility. Epidemiol 1995;6:485-489.
De-Kun Li, MD, PhD, MPH, is a senior research scientist at the
Division of Research, Kaiser Permanente Northern California.
Dr. Li completed his medical training and master’s degree in public health at
Shanghai Medical University, Shanghai, China. He then received his PhD in
epidemiology from the University of Washington, Seattle. Dr. Li has conducted
research in the areas of pregnancy outcomes, sudden infant death syndrome,
women's health, breast cancer, pharmacological effects on pregnancy outcomes,
genetic etiology, and occupational exposures since 1984. His research interests
include: reproductive, perinatal, and pediatric epidemiology, such as etiology of
miscarriage, sudden infant death syndrome, preterm delivery, preelcampsia, low
birth, infertility, cerebral palsy, birth defects, pediatric diseases (including
childhood cancer and neurological disorders), autoimmune diseases in relation to
maternal-fetal interaction, breast cancer, and risk factors for low semen quality.
Dr. Li’ research areas also include pharmacoepidemiolgical effect of medication
use during pregnancy, genetic determinants of adverse pregnancy outcomes, the
effect of electromagnetic fields on adverse pregnancy outcomes and low sperm
quality, and the effect of endocrine disruptors, specifically Bisphenol A (BPA), on
male and female reproductive systems. He is currently the associate editor of the
American Journal of Epidemiology. Dr. Li has participated in a National Institute
of Child Health and Human Development (NICHD) sponsored panel evaluation of
“Back to Sleep” campaign and Sudden Infant Death Syndrome risk. He has also
served as a member on the Ad Hoc Committee reviewing the NICHD program
project, and on several Special Emphasis Panels at National Institute of
Occupational Safety and Health and National Institute of Environmental Health
and Sciences reviewing grant proposals. He has served as a member of the
Policy Committee at the American College of Epidemiology. He was invited by
the National Academy of Science to participate as a panel member in the U.S.-
China Roundtable on Collaboration of Biomedical Research. In addition, he
teaches at Stanford University and supervises doctoral students from the
departments of epidemiology at UCB (University of California, Berkeley) and
UCLA (University of California, Los Angeles).
Dr. Li has published extensively with 29 first-authored publications. He has
obtained, as the principal investigator, numerous grants, ranging from $600,000
to $ 3.49 million from various federal agencies of the National Institutes of Health,
as well as the California Public Health Foundation. Many of his publications have
been widely reported by the national, international, and local news media
including recent studies of caffeine intake and miscarriage, pacifier use and use
of a fan in relation to SIDS risk, and depression during pregnancy and preterm
delivery. Other examples of work receiving wide media coverage include the risk
of miscarriage associated with EMF exposure, NSAID use and the risk of
miscarriage, hot tub use during pregnancy and the risk of miscarriage, and
maternal-fetal HLA compatibility and the risk of preterm delivery.
Current Position(s):
Research Scientist III, Division of Research, Kaiser Permanente Northern
Lecturer, Stanford University, Department of Health Research and Policy
Primary Research Interests:
Reproductive, prenatal, and pediatric epidemiology, such as etiology of infertility,
miscarriage, preterm delivery, preeclampsia, sudden infant death syndrome,
cerebral palsy, birth defects; pediatric diseases, including childhood cancer and
neurological disorders; autoimmune diseases in relation to maternal-fetal
interaction, and breast cancer.
Health effects of electromagnetic fields
Pharmacological effects of medication use during pregnancy on pregnancy
Genetic determinants of pregnancy outcome
Risk factors for poor semen quality
Health effect of endocrine disruptors, especially Bisphenol A (BPA), on male and
female reproductive systems