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Voltage Transients and Health

Explore the effects of voltage transients on health and technology, measurement methods, sources, and outcomes on wellbeing. Learn about related research and mechanisms of impact, as well as the importance of power quality.

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Voltage Transients and Health

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  1. Voltage Transients and Health Mikko Ahonen PhD, Researcher University of Tampere, Finland

  2. Table of Contents What are voltage transients – discussion about power quality How to measure and record voltage transients What are symptoms and mechanisms of effect Impact on wellbeing technology and its development A little Finnish-Russian pilot

  3. My background • Earlier worked in the Telecom and IT industry (TeliaSonera etc.) • PhD in computer science • Researcher at the University of Tampere • Co-operating with FinnMedi Ltd (Tampere, Finland) & with Kazan State University (Russia) &with measurement manufacturers (Germany & USA) • Founder and Partner Sustainable Mobile Ltd Measuring Services (http://www.sustainablemobile.com, http://twitter.com/SustainableM )

  4. From sine wave to transients - definitions

  5. 50 Hz sine wave & magnetic field Only magnetic fields starting from 0.3 uT (mikroTesla) have been linked to childhood leukemia (Greenland et al. 2000; Ahlbom et al., 2000). BUT results are inconclusive. Generally, electricity in its purest form does not seem to cause health problems (Mandeville et al., 1997 &McCann et al., 1993)

  6. Are there other factors? High electric fields(in connection to low-level magnetic fields) • Miller et al. (1996): 4 x leukemia risk in Canadian power company workers. • Guénel et al. (1996): 7 x brain cancer risk, when electric utility workers were exposed more than 25 years • Villeneuve et al. (2000) : 10 x leukemia risk , elevated Non-Hodgin’s lymphoma 123 "This study suggests that electric fields are potentially critical to cancer risk” 1 Please, note: Very limited amount of evidence

  7. Voltage transients (or simply “transients” or “micro surges”) “Transients are voltages and currents of short duration, typically less than one-half a cycle and possibly of larger amplitude than that of the normal steady state. These will either add or subtract from the nominal waveform.” Source: Dranetz BMI (1997)

  8. Harmonic overwaves (harmonics) “We define harmonics as voltages or currents at frequencies that are a multiple of the fundamental frequency. For European systems, the harmonic order is 100 Hz, 150 Hz, 200 Hz etc.” Source: Dranetz BMI (1997)

  9. Intermediate Frequencies (IF): 300 Hz – 100 kHz • Another name for the range of voltage transients • “As an overarching need, further research on intermediate frequencies (IF), usually taken as frequencies between 300 Hz and 100 kHz, is required, given the present lack of data in this area.” (WHO, 2007)

  10. From a review article – Voltage transients: “Environmental exposure to High-Frequency Voltage Transients is an interesting EMF exposure metric, which might explain the spurious results from epidemiological studies using 'standard' ELF and RF exposure metrics. However, at present, methodological problems in published studies prohibit the valid assessment of its biological activity.” Source: De Vocht (2010)

  11. What causes voltage transients?

  12. Main sources of voltage transients • Switching power on/off continuously • Static power converters with GR-diodes • Faulty electrical installations • Loose connections • Overloaded phases • - Dimmers • Energy-saving lamps • etc Picture: PhD, engineer Berthold Fuld (http://www.fuld.de/html/vortrag_pfc.pdf )

  13. Laptops – occasionally extremely high voltage transients Typical frequency values for highest micro surges caused by laptops: D laptop computer = 25 kHz D tower computer = 16.6 kHz A computers = 12.5 kHz Reason for high transient reading? Poor quality switching power supplies Source: D. Stetzer

  14. Low-frequency transient electric and magnetic fields coupling to child body / in the frequency range from 50 Hz up to 100 kHz - Ozen (2008) “The results show that the transient electric and magnetic fields would induce higher current density in the child body than power frequency fields with similar field strength”. 118004-times higher!

  15. Which frequency ranges match with highest amplitude of electrical fields? Source: Lundmark et al. 2005 A related finding, shown on the video. Demonstrated with a frequency generator.

  16. Which devices cause the biggest amplitude changes? (VDU = Video Display Unit, HF-fitting=fluorescent tubes equipped with high-frequency electronic ballasts) Source: Lundmark et al. 2005 See also: Oliveira et al. (2006)

  17. There are differences in lamps and light bulbs Video 1 Video 2 Source: Havas (2008) Accurate measurements of compact fluorescent lights: Maes (2009)

  18. General observations • Power quality has an effect on machines and their proper functioning. • Ground current problem noticed first in farms in USA and Canada. Related to voltage transients. • Various filters have been developed that reduce transients and harmonic overwaves. • The term ”Reactive Power Compensation” means improving power quality.

  19. Advanced How to measure voltage transients? (1/2) Unit: dV/dt  the average magnitude of the rate of change of voltage as a function of time. Measured often between 2 kHz – 150 kHz. Graham-Stetzer Fluke Gigahertz Solutions Fluke Scopemeter MicroSurge Meter VR1170 NFA-1000 199C Graham-Stetzer Fluke Gigahertz Solutions Fluke Scopemeter MicroSurge Meter VR1170 NFA-1000 199C

  20. How to measure transients? (2/2) Output: L / PE / N + Oscilloscope or Spectrum analyser Adapter for Harmonic Analysers / Auskoppeladapter For measurement of conducted electromagnetic interference in the frequency range from 10kHz to 30MHz based on CISPR 16 for measurements in accordance to EN 55011…22

  21. Transients in red – Minimal Measured with a Fluke Scopemeter

  22. Transients in red - Increased Measured with a Fluke Scopemeter

  23. Back to research results of transients Armstrong, Thériault et al. (1994):Workers exposed to transients had 6 x risk of developing lung cancer (even non-smokers). Consequence: The Canadian power company confiscated data and further research was not possible1 Milham & Morgan (2008)The teachers' chances of developing melanoma, thyroid cancer, and uterine cancer were particularly high, as great as 13 times the average.  Consequence: Researchers were not able to access the school any more 1 , 2 , 3 Please, note: Very limited amount of evidence + Extremely difficult to conduct studies in this area!

  24. Regularly clusters where low level magnetic field or power density readings can not explain the whole “picture” - examples http://www.news.com.au/national/another-abc-staffer-has-breast-cancer/story-e6frfkvr-1225833135423 http://www.nbcsandiego.com/news/health/Cancer-Cluster-at-UCSD-Building.html http://blink.ucsd.edu/safety/resources/public-health/lit-building/ Lots of discussion about melatonin and electro-magnetic fields: ELF-EMF may act at the cellular level to enhance breast cancer proliferation by blocking melatonin’s natural oncostatic action in MCF-7 cells (Liburdy, 1993; Luben et al., 1996; Morris et al., 1998; Blackman et al., 2001; Ishido et al., 2001, Girgert et al., 2010) . Is low level magnetic field value here more important than transient intensity? Please, note: Other environmental factors like heavy chemical exposure should be understood.

  25. Symptoms and improvements with transient filters (examples) Please, note: The evidence is still limited.

  26. About mechanisms of effect

  27. High tissue gradients by high voltage transients • Bawin and Adey (1976)showed that a 56 V/m ELF field (in 50 Hz) induces a tissue gradient of 10-7 V/cm, whereas a 56 V/m 147 MHz signal induces a tissue gradient of 10-1 V/cm, a million times higher. (See also: Cherry, 2002; Blank & Goodman, 2004)

  28. Professor Martin Blank About mechanism: Stress response in DNA • ”Induction of the stress response involves activation of DNA, and despite the large difference in energy between ELF and RF, the same cellular pathways respond in both frequency ranges. Specific DNA sequences on the promoter of the HSP70 stress gene are responsive to EMF, and studies with model biochemical systems suggest that EMF could interact directly with electrons in DNA. While low energy EMF interacts with DNA to induce the stress response, increasing EMF energy in the RF range can lead to breaks in DNA strands”. Blank & Goodman (2009)

  29. About mechanisms: Gap junctions = protein bridges between cells  Transients may interfere gap opening Gap junction flow is significantly altered as a function of 50 Hz magnetic field strength, Li et al. (1999). Gap junction openingis regulated by calcium ions and pH, Alberts et al. (1994). (Experiments in Canada: pH-levels acid when high transients, alcaline when minimal transients).

  30. About mechanism: Alternative explanations • Atmosferics, weather-related electrical activity in kHz-range have historically caused health problems (Schienle, Stark, Walter & Vaitl, 1996; Reiter, 1995; Dubrov, 1978) and now this frequency range is artificially created in the electrical network. • Certain frequencies inhibit DNA-repair and cause weakening of the immune system (Belyaev et al. (2009), RNCNIRP (2008). Frequency-windows exist and some frequence/power density combinations are harmful. (Blackman, 2009).

  31. About mechanism – One expert opinion Transients are created when current is repeatedly interrupted. A CFL, for instance, saves energy by turning itself on and off repeatedly, as many as 100,000 times per second. So how does the human body respond to this pulsing radiation? "Think of a magnet," explains Dave Stetzer, an electrical engineer and power supply expert in Blair, WI. "Opposite charges attract, and like charges repel. When a transient is going positive, the negatively charged electrons in your body move toward that positive charge. When the transient flips to negative, the body's electrons are pushed back. Remember, these positive-negative shifts are occurring many thousands of times per second, so the electrons in your body are oscillating to that tune. Your body becomes charged up because you're basically coupled to the transient's electric field."Keep in mind that all the cells in your body, whether islets in the pancreas awaiting a signal to manufacture insulin or white blood cells speeding to the site of an injury, use electricity — or "electron change" — to communicate with each other. By overlapping the body's signaling mechanisms, could transients interfere with the secretion of insulin, drown out the call-and-response of the immune system, and cause other physical havoc?1 ,2 , 3

  32. About mechanism: There is much we don’t know, no single mechanism is fully established!

  33. Impact on wellbeing technology and its development

  34. Mobile phone components – producing transients continuosly in stand-by mode Question: How risky is it to keep to a mobile phone attached to the body continuously? Is it really a personal health monitoring device?

  35. Smart meters and other utility equipment – transmitting RF-signals in the electrical circuit and power lines • Vignati & Giuliani (1997) investigated powerlines: “Electric current at 100 kHz can penetrate much more deeply through the plasmatic membrane than current at 50/60 Hz.” • Italy: Frequencies used by utilities for data transmission range from 104 to 288 kHz. • Israel: Powerlines lines are used to transfer information. The frequency range is 30 to 450 kHz. • What is the current and future situation? • Which frequencies are the most critical from health perspective?

  36. What happens when RF-frequencies are “run” in a powerline that is originally optimised for 50 Hz sine wave? The gain of the powerline as a radiator increases rapidly with frequency (Hare, 2003 ).  Powerline starts to act as an antenna and extends wider. The gain of the powerline as a radiator increases rapidly with frequency (Hare, 2003 ).  Powerline starts to act as an antenna and extends wider.

  37. Filters reduce voltage transients • A simple condenser/capacitor as a filter • Or… a special line filter (from Graham-Stetzer, Bajog etc.).  Suitable for interference suppression for switching power supplies and phase controlled modulators

  38. Observation: Voltage transients are similar to pulsed microwaves.Making epidemiological studies is very complicated. Radio and TV-transmitters: Effect: Dolk et al. (1997a), Hocking & Gordon (2003),Ha et al. (2007), Mascarinec et al. (1994, Michelozzi et al. (2002), Morton & Phillips (1983), Park et al. (2004) [Mostly increased leukemias and lymphomas] No effect: Dolk et al. (1997b), Mersenich et al. (2008) Mobile Phone Base Stations: Effect:Abdel-Rassoulet al. (2007), Eger et al. (2004), Hutter et al. (2006), Navarro et al. (2003), Santini et al. (2003), Wolf & Wolf (2004), Blettner et al. (2008)[great variety: from headaches to breast cancer] No effect: Meyer et al. (2006), Berg-Beckhoff et al. (2009) http://www.chronicexposure.org

  39. Our little pilot in a Finnish (and a Russian) school • Starting point: Teachers and students had many health problems and complaints in a high school. Minimal amount of mold was found and removed. Ventilation was improved in the school. Still, problems remained. • We measured transients in every class room. Protocol: Similar to Trushina et al. (2010), co-operating with prof. Maksim Trushin • Thereafter we checked if symptoms and transient readings match. Interestingly: There was a match, the 2 teachers who had the biggest health problems (asthma that required inhalators, skin problems, watery eyes, continuous coughing) worked in those 2 class rooms with highest transient readings. • Outcome: Filters that drop the HF-transients were installed for testing purposes. Symptoms of teachers were reduced. We need(ed) more information about exposure conditions at home + earlier chemical exposure. Reseach continues both in Tampere-area and Kazan … Additionally, we have a pilot starting in a hospital.

  40. Are we saving energy on the cost of health? Already we know that many appliances and machines could be designed in a better way. Our research hopefully helps to make those “Smart Meters”, “Smart Grids” and “Smart Houses” more sustainable and healthier. Additionally, electronics, wires and power supplies in schools, homes and work places could be improved with small costs and simple means. Within Green IT and Green Computing we should perhaps start discussing about health issues and transients.

  41. What about standards and guidance levels? DIN EN 61000-3-2; VDE 0838-2:2010-03 Electromagnetic compatibility (EMC) ICNIRP-guidance level – no consideration of: - wavelength/frequency - overall duration of exposure (continuous, interrupted), acute and chronic exposures - polarization (linear, circular) - continues wave (CW) and pulsed fields (pulse repetition rate, pulse width or duty cycle, pulse shape, pulse to average power, etc.) - modulation (amplitude, frequency, phase, complex) - static magnetic field at the place of exposure - electromagnetic stray field (Belyaev, 2008; Blackman, 2007) SanPin is perhaps the only health standard that considers these?

  42. Thank you!Questions and comments welcome! Mikko Ahonen PhD, Researcher University of Tampere Finland Telephone +358-3-3551 8069 Skype ahosmikko E-mail mikko . ahonen [at] uta . fi Info http://www.uta.fi/~mikko.ahonen/ Blog http://beyondradiation.blogs.com

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