The Applicability of Current and Past RF Biological Research to New

Technology (3G): Portability Requires a Mechanism.

The Applicability of Current and Past The Applicability of Current and Past RF Biological Research to New RF Biological Research to New

Technology (3G): Portability Requires a Technology (3G): Portability Requires a Mechanism.Mechanism.

M. L. SwicordMotorola Florida Research Lab,

Plantation, FL 33322Phone: 954-723-4898, Fax: 954-723-5611,

Email: mays.swicord@motorola.com

OutlineOutlineOutline

• Overview of mobile telephony related research.

• Listing of various mobile telephony signals.

• Is current research portable to new technology (3G)?

• Portability requires a mechanism.• Two approaches to defining a

mechanism.• Only established mechanism is

thermal. Thermal results are portable.

Completed Ongoing Total• Cancer Relevant or related

– Epidemiological studies 8 18 26– Standard bioassays 6 8 14– Sensitized in vivo studies 11 7 18– Acute in vivo studies 22 5 27– In vitro studies 50 26 76–

– Total Cancer Studies 97 64 161

• Non-Cancer studies– Epidemiology 4 0 4– Acute in vivo studies 32 10 42– In vitro studies 15 10 25 – Human Studies 45 21 66

– Total Non-Cancer Studies 96 41 137

– Grand Totals 193 105 298All studies are listed on the WHO web site: http://www-nt.who.int/peh-emf/database.htm

Current Mobile Telephony Related StudiesCurrent Mobile Telephony Related Studies

Example Mobile Telephony SignalsSignal Type Frequency ModulationTETRA 380 – 470 MHz 17 Hz (TDMA)MIRS 806-821 MHz 11.1 Hz (TDMA)NADC 824-849 MHz 50 Hz (TDMA)CDMA 824-849 MHz multichannel (800 Hz)

ANALOG 824-849 MHz FMGSM 890-915 MHz 217 Hz (TDMA)PDC 929.2 MHz /1.5 GHz 50 Hz (TDMA)

IRIDIUM 1616-1626 MHz 11 Hz (TDMA) PCS 1805-1880 MHz 217 Hz (TDMA)GSM 1800 MHz 217 Hz (TDMA)GSM 1900 MHz 217 Hz (TDMA)

Are current research results portable to new technologies?Are current research results portable Are current research results portable to new to new technologies?technologies?

• Is it necessary to test all possible combinations of frequency and modulation to determine whether or not each signal type will or will not cause adverse health effects?

Thus observed effects due to a thermal mechanism are portable.

• The answer depends on the mechanism of interaction of the RF fields with the biological system.

• A thermal mechanism depends only on the amount of energy absorbed and thus its frequency dependence is completely predictable.

Are current research results portable to new technologies?Are current research results portable Are current research results portable to to new technologies?new technologies?

• A non-thermal mechanism would not only be energy dependent but would be expected to exhibit frequency dependent responses, modulation dependent responses or both

• The current 300 mobile telephony studies using all technologies are testing the hypothesis of whether there is a frequency dependent or modulation dependent response.

• The absence of any consistent or replicable effect at non-thermal levels would suggest the absence of athemal effects without heating due to absorption of RF energy.

Finding an athermal responseFinding an athermal responseFinding an athermal response

• Two approaches – Biological studies & physical mechanisms studies.

First Approach–Find a repeatable biological response that can be studied to determine the physical and biochemical response.

–To date this approach has probably not been successful due to either:

•Statistical variation - WellWell--done studies are always done studies are always subject to statistical variationsubject to statistical variation

––If 100 studies are conducted and statistically If 100 studies are conducted and statistically evaluated on a 95% confidence level then 5 will be evaluated on a 95% confidence level then 5 will be expected to differ because of statistical variation expected to differ because of statistical variation

•Errors in experimental design

•Experimental errors

Errors in experimental designErrors in experimental designErrors in experimental design

•• Inadequate controlsInadequate controls–– Sham/sham experiments to determine the system variabilitySham/sham experiments to determine the system variability–– Positive controls to test the system sensitivityPositive controls to test the system sensitivity–– Sham controlsSham controls

•• Imprecise or overly complex hypothesis (not testable)Imprecise or overly complex hypothesis (not testable)•• Exposure range inadequate to define dose responseExposure range inadequate to define dose response•• Inadequate statistical powerInadequate statistical power

–– Statistical tests not defined Statistical tests not defined a priori a priori –– Number of repeat experimental runsNumber of repeat experimental runs–– Multiple comparisonsMultiple comparisons

Experimental errorsExperimental errorsExperimental errors

•• Temperature controlTemperature control–– ‘‘AthermalAthermal’’effects at high SAR in vitroeffects at high SAR in vitro–– Thermal stress in studies with laboratory animalsThermal stress in studies with laboratory animals–– Subtle thermal effectsSubtle thermal effects

•• Microwave hearing as artifact in animal Microwave hearing as artifact in animal studiesstudies

•• Poor or improper Poor or improper dosimetrydosimetry•• Improper handling techniquesImproper handling techniques

–– Time sequence of treatmentsTime sequence of treatments–– Stress due to improper handling of samplesStress due to improper handling of samples

Second Approach: Postulate a testable theoretical hypothesis and devise an experimental biological test.

Second Approach: Second Approach: Postulate a testable Postulate a testable theoretical hypothesis and devise an experimental theoretical hypothesis and devise an experimental biological test.biological test.

•• Workshop held May 2001 in Washington DC. Workshop held May 2001 in Washington DC. Experts considered the plausibility of various Experts considered the plausibility of various mechanisms.mechanisms.

•• Workshop evaluated physical mechanisms of Workshop evaluated physical mechanisms of interaction from a theoretical basis only. Subjects interaction from a theoretical basis only. Subjects considered included: considered included: –– Temporal and spatial temperature gradientsTemporal and spatial temperature gradients–– Alteration of membrane potentialAlteration of membrane potential–– Membrane rectificationMembrane rectification–– Polarization of structures or moleculesPolarization of structures or molecules–– RF pumping & chemical kineticsRF pumping & chemical kinetics–– Magnetic dipole interactionsMagnetic dipole interactions–– Cooperative interactions and coherenceCooperative interactions and coherence

Mechanism Plausibility Other comments

Temporal and spatial temperature gradients

Possible Need for theoretical evaluation of temperature and energy gradients (temporal and spatial) at the microscopic (nano-scale) and macroscopic level.

Alteration of membrane potential

Not plausible for brief exposures at low levels

Need to perform calculations to determine the thresholds.

Membrane rectification

Not generally plausible because small signals will result in insignificant non-linear responses.

Rectification may not be possible above a few MHz. Need to (a) define theoretical lower limits of field strength for membrane interaction and (b) theoretically investigate whether multiple-cell structures create situation for rectification or whether one can get a large oscillating or rectification change in membrane potential above 10 MHz.

Mechanism Plausibility Other comments

Polarization of structures or molecules.

Not plausible for most cases

A need to theoretically investigate whether small fields could affect a process that is teetering between two nearly equal energy states.

RF pumping & chemical kinetics.

Not plausible due to critical damping of any modes that may or may not exist.

Theoretically examine: a) Isolated molecules (caged structures) to determine whether such isolation could exist and lead to realizable vibrational modes. b) The possibility and limitations of 2 -photon, 2 -phonon, or 1-photon plus 1-phonon interactions.c) Determine whether ballistic transmission is realizable in biological systems

Magnetic dipole interactions

Not plausible. Published calculations show that energy absorbed in magnetite is too small to cause significant temperature rise. Magnetic fields effects on free radical formation should be

theoretically evaluated.

Mechanism Plausibility Other comments

Synchronization Synchronized systems need to be theoretically examined to determine whether there may be an increased level of response in those systems that otherwise are implausible.

Cooperative Not plausible No known way of coupling cooperative systems to RF energy.

Coherence Not plausible Critical damping would prevent appearance of any modes that might exist.

Mechanisms Workshop ConclusionMechanisms Workshop ConclusionMechanisms Workshop Conclusion

•• This workshop concluded in part: This workshop concluded in part: ““For exposures to For exposures to RF energy from sources in the general environment RF energy from sources in the general environment and from use of mobile telephone devices, the only and from use of mobile telephone devices, the only clearly plausible mechanisms for RF interactions clearly plausible mechanisms for RF interactions with biological systems involve heating.with biological systems involve heating.””

•• For a complete summary of this MMF sponsored For a complete summary of this MMF sponsored workshop see theworkshop see the research section at research section at http://www.http://www.mmfaimmfai.org/.org/. .

ConclusionsConclusionsConclusions

• Of the approximately 300 studies on mobile telephony and health almost 200 have been completed. The vast majority of competed studies show no effect. There is no constant reported positive finding suggesting an accepted non-thermal effect

• To determine whether current experimental findings are applicable to all current and proposed (3G) technologies one must understand the basic physical mechanism that is causing any biological response.

• Currently only effects in two main areas have been established:– Thermal effects of RF energy– Neurostimulation by RF fields and currents

Conclusions continuedConclusions continuedConclusions continued

• Theoretical analysis does not provide current support for non-thermal effects.

• No experimental model has been developed which provides a repeatable, generally accepted non-thermal response. Without such a experimental model the systematic pursuit of any non-thermal mechanism is not realistic.

• The lack of evidence or any real indication of a non-thermal mechanism leads one to conclude that current thermally based standards are sound and thus all current research findings are portable to all current and new technologies.