REVOLT opposing unnecessary, excessive and intrusive powerline development

opposing unnecessary, excessive and intrusive powerline development

REVOLT Newsletter 247

Revolt news 20/01/2008

1. Two new research papers show positive laboratory findings for biological effects of RF EMFs (APPENDIX A). One shows increased chromosome aberrations in human lymphocyte samples, the other increased cell death in cortical neurons of rats. 


2. On 9th Jan I met the developers of the Seamer windfarm (news246.2) in Hambleton District. It is to be a small wind farm, with about six standard 120 metre high turbines. It will also be connected to the distribution system at 33kV, not to the nearby 400kV transmission line. The impact of the connecting line would seem to be minimal.


3. A Seamer parish meeting of some 50 people last week is reported to have voted unanimously to oppose the wind farm. On the one hand it seems to fit the national and regional policies imposed on us. On the other hand 120 metre high turbines stand out as having the greatest visual impact ever inflicted on the Hambleton District countryside.


4. Hambleton District Council advise that they have had only two approaches about possible wind farms, the Seamer proposal as above and a tentative approach about a site at East Cowton, believed to be around Geraldine's Plantation about 3 km south east of the village. As signalled in news246.4, I hope to keep track of approaches made about possible wind farm sites in this District.


5. National Grid's EMF expert John Swanson has kindly posted some helpful notes on the rates of fall-off of magnetic fields from powerlines with distance from the lines. The notes indicate that the ideal inverse-cube fall-off is not achieved for real transposed double-circuit lines. This makes little difference in the near-distance but it is important for fields falling off over a few hundred metres (APPENDIX B).


6. This month's White Paper on Nuclear Power gives the green light to nuclear power stations, at least for renewal of nuclear power stations on existing sites, through private investment including provision for waste management and decommissioning. One nuclear power station in each geographical region would provide more, and more reliable, low-carbon power than all the renewable generation envisaged. The White Paper can be seen at 

7. The International Agency for Research in Cancer (IARC, part of WHO) confirmed in a press release 5-12-07 that it is rating shift work which disrupts circadian rhythm as a probable human carcinogen (Class 2A). This is important to EMF work, as melatonin disruption is cited as a potential factor. Further, the biological mechanisms of light-at-night and EMF may both involve melatonin and may be interactive. However, it is the evidence in animal experiments which secures the Class 2A for shift work, but which is "inadequate" for EMF. See APPENDIX C and the IARC site: 


8. Reports at BBC Online and in the Independent on Sunday ("Mobile phone radiation wrecks your sleep", 20-1-08) draw on new experimental studies at universities in Sweden and USA showing that mobile phone type EMF disrupts sleep in exposed people compared with sham-exposed controls. These results complement those for shift work and light-at-night which led to the IARC 2A rating (see above). Now similar well-focused experimental studies are needed for power frequency EMF at night and just before sleep, to examine the effect on sleep. Sleep disruption impairs the immune system, which may partly explain associated increases of cancer.





APPENDIX A From microwave news:


January 9... It's a new year and maybe, just maybe, it signals a new outlook at Radiation Research, a journal with a reputation for publishing negative findings (see, for instance, "Radiation Research and The Cult of Negative Results.")

The journal's January issue features two reports that point to non-thermal effects of RF radiation. The first paper, from Israel's Tel Aviv University, shows that 800 MHz radiation at SARs of 2.9 W/Kg and 4.1 W/Kg can cause chromosomal aberrations in human blood lymphocytes following a 72-hour exposure. The second paper, from a group in Limoges, France, implicates 900 MHz RF radiation in apoptosis (cell death).

The Tel-Aviv group includes Rafi Korenstein, who has long been working on genotoxic effects of electromagnetic radiation. The Israelis advise that their new results "should be taken into consideration when assessing the health risk after continuous exposure to RF radiation at an SAR close to the current threshold set by ICNIRP."





APPENDIX B Notes on magnetic field fall-off with distance from powerlines.


National Grid's EMF expert John Swanson has kindly posted some helpful notes on the rates of fall-off of magnetic fields from powerlines with distance from the lines. The notes indicate that the ideal inverse-cube fall-off is not achieved for real transposed double-circuit lines, partly because of the sloping profile of conductors, and that something nearer to inverse-square would be more typical (as shown in the fourth and fifth graphs). Be careful to interpret the graphs correctly: they show the localised fall-off power, not the fields themselves (which fall towards zero). 


For single-circuit and untransposed double-circuit lines, lack of perfect cancellation of the phase currents in a circuit means that the fields could have a theoretical asymptotic fall-off which is only inverse-distance, except for possible effects of return ground currents commensurate with the imbalance, which depend on ground resistivity. The high resistivity case, which seems closest to real measurements, is shown on the last (sixth) graph in this series, where it comes close to an inverse-distance fall-off at around 500 metres.


For a graph of field versus distance for a particular transposed double-circuit line, go to the above link and click on "more" between the fourth and fifth graphs on that page. That click is for more about "zero-sequence currents". Then scroll down to the second graph on the resulting page. It shows three curves A, B and C with progressively more sophisticated models. Curve C is the best and it agrees well with measurements.


All of those three curves A, B and C are very similar up to about 100 metres, as the asymptotic effects have not become large enough to be noticed. Curve C and the measurements are substantially higher than the other two curves after 200 metres. This might be significant in terms of potential public health impact if there is an underlying dose-response relation which is progressive, rather than the threshold model.


While curve C stays significantly above zero out to 500 metres and more, after about 300 metres it is down to the region of 10 nT. That is becoming insignificant compared with typical fields due to sources inside homes. Even with a progressive dose-response model, the additional effect of fields at this level should be relatively unimportant, though the impact on the exposed population could be estimated.


Over the last few weeks I have enjoyed exchanging technical correspondence with John Swanson on the subject of fall-off rates of EMFs from powerlines, and it is nice that we are able now to say that we are "pretty much agreed".


It would still be useful to have "independent replication" in the form of measurements of fields from UK powerlines from other sources. In the end it is measurements which validate the theory and especially validate its application and computer programming.





APPENDIX C Shift work gets IARC 2A rating (from IARC press release 180).

A summary of these conclusions has been published in the December issue of The Lancet Oncology. Full results will be published next year as volume 98 of the IARC Monographs.

Shiftwork that involves circadian disruption is "probably carcinogenic to humans"

Epidemiological studies have found that long-term nightworkers have a higher risk of breast cancer risk than women who do not work at night. These studies have involved mainly nurses and flight attendants. The studies are consistent with animal studies that demonstrate that constant light, dim light at night, or simulated chronic jet lag can substantially increase tumour development. Other experimental studies show that reducing melatonin levels at night increases the incidence or growth of tumours.

These results may be explained by the disruption of the circadian system that is caused by exposure to light at night. This can alter sleep-activity patterns, suppress melatonin production, and disregulate genes involved in tumour development. Among the many different patterns of shiftwork, those that include nightwork are most disruptive to the circadian system.

"Nearly 20% of the working population in Europe and North America is engaged in shiftwork, which is most prevalent in the health-care, industrial, transportation, communications, and hospitality sectors: To date, most studies have focussed on breast cancer in nurses and flight attendants. Now more studies are needed to examine this potential risk in other professions and for other cancers," noted Dr Cogliano, Head of the IARC Monographs Programme.






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