05/10/2015-tyw-Kilohertz Range EMF is Likely Less Harmful
05/10/2015-tyw-Kilohertz Range EMF is Likely Less Harmful
Timestamp:<Mon-05-Oct-2015>
We all accept that non-native Electromagnetic Fields (nn-EMF for short) is not a good thing.
我们都承认，非本地电磁场(nn-EMF简称)不是一件好事。
For those who are unconvinced, just go read the following books:
对于那些不相信的人，可以去读下面的书:
①https://en.wikipedia.org/wiki/The_Body_Electric_(book)
②http://www.amazon.com/Cross-Currents-Robert-O-Becker/dp/0874776090
③http://www.goingsomewherebook.com/
But of course, we're likely going to be stuck with nn-EMF for the rest of our lives, so the logical thing to do is to figure out ways to use the least harmful forms of nn-EMF.
但当然，我们很可能在余生中都要使用nn-EMF，所以合理的做法是找出使用危害最小形式的nn-EMF的方法。
That led me to dig up some research regarding the intermediate range kilohertz EMF fields.
这让我找到了一些关于中程千赫兹电磁场的研究。
Existing Frequency Bands in Use
目前正在使用的频带
Extreme Low Frequency (ELF) EMF is very well studied, and is the most harmful, even at low powers.
极低频(ELF)电动势已经得到了很好的研究，即使在低功率时也是最有害的。
For direct stimulation of biologic tissues, we are usually looking at frequencies of anywhere from 5Hz to 1,000Hz. Some heating effect will occur until just below 3,000Hz.
对于生物组织的直接刺激，我们通常观察频率在5Hz到1000hz之间的任何地方。一些加热效应会一直持续到略低于3,000赫兹。
The Frequency of EMFs used in our wide area telecomm systems are:
广域电讯系统使用的电磁脉冲频率如下:
•2G, 3G, and 4G bands: 850MHz, 900MHz, 1,800MHz, and 2100MHz
2G、3G、4G频段:850MHz、900MHz、1800 mhz、2100MHz
•GSM: 850MHz and 1,900MHz
All of these are REALLY bad for you.所有这些都对你有害。
The shorter-range networks:
短程网络:
•WiMax: 2GHz to 11GHz, with 3.5GHz fixed band
WiMax: 2GHz到11GHz，固定频段3.5GHz
•Bluetooth蓝牙: 2.4GHz
•Wifi: 2.4GHz, 3.6GHz, 4.9GHz, 5GHz, 5.9GHz
All of these are REALLY bad for you.所有这些都对你有害。
Technically, the radio frequency range includes the lower kilohertz range EMFs, but realistically, radio towers use higher frequency bands:
从技术上讲，无线电频率范围包括较低的千赫兹范围的电磁场，但实际上，无线电塔使用更高的频带:
•Longwave AM Radio: 148.5 kHz to 283.5 kHz (LF)长
•Mediumwave AM Radio: 530 kHz to 1710 kHz (MF)中
•Shortwave AM Radio: 3 MHz to 30 MHz (HF)短
All of these are REALLY bad for you.所有这些都对你有害。
Microwaves are also obviously REALLY bad, and these are in the 300+MHz range.
微波显然也很糟糕，这些在300+MHz范围内。
Low-to-Mid Kilohertz Range
低度到中度赫兹范围
That actually leaves an “unexplored region” in the 3kHz to 200kHz range.
这实际上留下了一个3kHz至200kHz范围的“未开发区域”。
Obviously, we would want to use as little power as needed.
显然，我们希望尽可能少地使用电力。
Low power kilohertz range EMF not as bad?
低功率千赫兹范围的电动势并不坏?
TBH, I was surprised at some of what I found. These fields were not as harmful as I thought, and many studies failed to produce harm.
说实话，我对我的一些发现感到惊讶。这些领域并没有我想象的那么有害，很多研究都没有产生危害。
First study I found was this rat study. Using 20kHz triangular magnetic fields –
我发现的第一个研究是这个老鼠研究。使用20kHz的三角形磁场——
http://www.tandfonline.com/doi/abs/10.1080/09553000600721809
These were Sprague Dawley outbred rats. ie: not the inbred Gnotobiotic, germ-free rats, which easily succumb to any form of stress, and which are often used in EMF related studies or Cancer studies. I don't like such germ-free rats because they get sick too easily. In that sense, this study is good in that it uses “more natural” organisms.
这些是斯普拉格·道利近亲繁殖的老鼠。例如:不是近亲繁殖的无菌、无菌的老鼠，它们很容易屈服于任何形式的压力，经常被用于电磁场相关研究或癌症研究。我不喜欢无菌老鼠，因为它们太容易生病了。从这个意义上说，这项研究的优点在于它使用了“更自然”的生物体。
Sample size of 80 rats was decent.
80只大鼠样本量良好。
EMF field was MASSIVE: 6.25 μT rms for 8 h/day for 12 or 18 month. (6.25 μT is 62.5mG. We usually want to stay below 0.1mG for ELF EMF)
电磁场强度大:6.25 μT rms, 8 h/d，持续12或18个月。(6.25 μT为62.5mG。我们通常希望ELF EMF保持在0.1mG以下)
Quote:
Urinalysis [pH, glucose, protein, ketone bodies, red blood cells (RBC), nitrogen, bilirubin, urobilinogen, and specific gravity], hematological analysis (RBC, hemoglobin, hematocrit, thrombocyte count, and leucocyte count), blood biochemistry (total protein, blood urea nitrogen, creatinine, glucose, total bilirubin, total cholesterol, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase), and histopathological analysis of organs (thymus, stomach, intestine, liver, kidney, testis, ovary, spleen, brain, heart, and lung) were performed.
引用:
尿液分析[pH，葡萄糖，蛋白质，酮体，红细胞(RBC)，氮，胆红素，尿胆素原，比重]，血液学分析(RBC，血红蛋白，红细胞压积，血小板计数，白细胞计数)，血液生化(总蛋白，血尿素氮，肌酐，葡萄糖，总胆红素，总胆固醇，对各器官(胸腺、胃、肠、肝、肾、睾丸、卵巢、脾、脑、心、肺)进行组织病理学分析。
Results:
No significant differences were seen between 20 kHz magnetic-fields exposed rats and sham-exposed rats in body and organ weights, hematological analysis, blood biochemistry, urinalysis data, and histopathological examination, except for the numbers of neutrophiles and lymphocytes in female rats
The number of neutrophiles was significantly increased in female rats on the 12th month after exposure, and the number of lymphocytes in female rats was significantly decreased on the 18th month.
结果:
除雌性大鼠中性粒细胞和淋巴细胞的数量外，20 kHz磁场照射大鼠与假照射大鼠在体和器官重量、血液学分析、血液生化、尿液分析和组织病理学检查方面无显著差异。暴露12个月时，雌性大鼠中性粒细胞数量显著增加，18个月时，雌性大鼠淋巴细胞数量显著减少。
Basically, some immune related function after constant exposure to a massive kilohertz field for 1/3rd to half their lives (these rats typically live 24-36 months), which wasn't even enough to impact other blood markers.
基本上，一些免疫相关的功能在持续暴露在巨大的千赫兹磁场中三分之一到一半的寿命后(这些老鼠通常活24-36个月)，这甚至不足以影响其他血液标记物。
That's a hopeful start …..
这是一个充满希望的开始…..
Another study, with Chick Embryos
另一项关于小鸡胚胎的研究
http://www.tandfonline.com/doi/abs/10.1080/0002889738506818
Sixty-two test eggs were exposed for 19 days to a 26-kHz, 160-gauss peak-to-peak a-c field. Seventy unexposed eggs were maintained under the same environmental conditions as the controls.
The percent of eggs hatched from the initial number was 64.5 for the exposed and 48.5 for the controls
62只试验卵暴露在26千赫、160高斯的峰-峰交流场中19天。70只未暴露的卵与对照组保持在相同的环境条件下。暴露组孵化率64.5%，对照组48.5%。
Again, another massive field, and some indication of increased developmental speed in the exposed bunch. I personally don't think we can draw too many conclusions from this, but I was expecting no eggs to hatch with such a huge field.
同样，这是另一个巨大的领域，一些迹象表明，在暴露的群体中，发展速度增加了。我个人不认为我们可以从中得出太多的结论，但我没想到在这么大的一块田地里孵出什么蛋来。
Another rat study
另一项老鼠实验
http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA207468
The three elements of the research were designed to examine possible biological and medical effects of exposure to the near-field of Loran-C transmitters that operates in a pulse modulated mode at a carrier frequency of 100 KHz
Neurochemical studies tested the effects of single and repeated in vivo exposure to a simulated Loran-C type waveform on the rat brain biogenic amine and opiate receptor systems.
这项研究的三个组成部分旨在检查接触罗兰- c发射机近场可能产生的生物和医学影响。罗兰- c发射机以脉冲调制方式工作，载频为100千赫。
神经化学研究测试了单一和重复体内暴露于模拟罗兰- c型波形对大鼠脑生物胺和阿片受体系统的影响。
Results:
We found AM-PM differences in the levels of amines but no field-related effect was detected.
Number and affinity of opiate receptors were also not affected by exposure to the combined electric (3 kV/m rms) and magnetic (48 uT rms) components of this Loran-C Type waveform.
结果:
我们发现AM-PM在胺的水平上存在差异，但没有检测到场相关的影响。
阿片受体的数量和亲和力也不受Loran-C型波形的联合电(3 kV/m rms)和磁(48 uT rms)分量的影响。
Behavioral studies compared the rat's known ability to detect low intensity 60 Hz electric fields (10 KV/m) with potential detection of Loran-like fields. The data showed that rats trained in an operant conditioning task did not reliably detect the 100 KHz at any field strength used (0 to 9 kV/m).
行为研究比较了老鼠已知的检测60赫兹低强度电场(10 KV/m)的能力和对罗兰类电场的潜在检测能力。数据显示，在操作性条件反射任务中训练的大鼠在任何场强(0到9千伏/米)下都不能可靠地检测到100千赫。
Biochemical studies measured ornithine decarboxylase (ODC) activity in tissue culture cells to monitor membrane signal transduction. Exposure to the Loran-C type waveform at 10mV/cm field strength did not modify basal ODC activity in primary bone cells from mouse calvaria.
生化研究测定组织培养细胞中鸟氨酸脱羧酶(ODC)的活性，以监测膜信号转导。暴露于10mV/cm场强的罗兰- c型波形并没有改变小鼠颅骨原代骨细胞的基础ODC活性。
Which is to basically say that there was no effect at all …..
也就是说根本没有任何影响…..
Another rat study regarding fertility rates另一项关于生育率的老鼠研究
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3866534/
Metaphase II ovums were separated, and sperms obtained by “swim out” method were added to metaphase II ovums in the culture medium.
分离中期II卵细胞，将“游出”法获得的精子加入培养基中中期II卵细胞中。
The experimental group was exposed to 1.3 millitesla pulsed electromagnetic field at 4 kilohertz frequency for 5 hours. To assess the efficacy, we considered the identification of two-pronuclear zygote (2PN) under microscope as fertilizing criterion.
实验组暴露于频率为4千赫兹的1.3毫特斯拉脉冲电磁场中5小时。以显微镜下鉴定双原核受精卵(2PN)为受精标准，评价其有效性。
Results:
In vitro fertilization (IVF) success rate was 77% in extremely low frequency- pulsed electromagnetic field (ELFPEMF) for exposed group (experimental), whereas the rate was 68% for control group.
Again, like the chick study, not much difference in success rates, implying that the acute effect was not large (exposure was only 5 hours).
结果:
极低频脉冲电磁场(ELFPEMF)照射组体外受精(IVF)成功率为77%(实验组)，对照组为68%。同样，就像小鸡研究一样，成功率没有太大的差异，这意味着急性影响不大(接触只有5小时)。
In vitro Bacterial study, which exposed bacteria to the fields from an Induction Cooktop在体外细菌研究，暴露细菌的领域从诱导炉灶
http://onlinelibrary.wiley.com/doi/10.1002/bem.20334/abstract
Since the cellular genotoxicity of IF magnetic fields has not been examined in cultured cells, we examined the effects of these fields at a magnetic flux density of 532 ± 20 μT at 23 kHz, using an exposure unit with a built-in CO2 incubator.
由于尚未在培养细胞中检测IF磁场的细胞遗传毒性，我们使用带有内置CO2培养箱的暴露装置，在23 kHz的磁通密度为532±20 μT时检测了这些磁场的影响。
Results:
Exposure to the IF magnetic field at 532 µT for 2 h did not affect the growth of CHO-K1 cells and caused no mutagenic effects in bacterial mutation assays.
Exposure to the IF magnetic field for 2 h induced neither single nor double DNA strand breaks in comet assays, and caused no significant change in the mutation frequency at the HPRT locus compared to sham exposure.
From these results, we suggest that exposure to an IF magnetic field for 2 h does not cause cellular genotoxicity in bacteria and in Chinese hamster cells. However, the possibility of effects on other cellular functions remains, and further studies on the cellular effects of IF magnetic fields are required.
结果:
在细菌突变试验中，532 μ T IF磁场照射2 h不影响CHO-K1细胞的生长，也不产生致突变作用。
在彗星检测中，暴露于IF磁场2小时既没有引起单链或双链DNA断裂，与假暴露相比，HPRT位点的突变频率也没有显著变化。
从这些结果，我们认为，暴露于IF磁场2小时不会引起细菌和中国仓鼠细胞的细胞遗传毒性。但IF磁场对其他细胞功能影响的可能性仍然存在，需要进一步研究IF磁场对细胞的影响。
Again, no effects on bacteria.
同样，对细菌没有影响。
It is a stretch to say that there will be no effects on our prokaryotic Mitochondria, but again, I am surprised by how virtually no harm was caused.
说它不会对我们的原核线粒体造成影响，这有些牵强，但我再次对它几乎没有造成伤害感到惊讶。
Review study of humans人类研究综述
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4305112/
Again, showing what we already know, that 50Hz fields are the most harmful. But again, it admits that not much is known about the low kilohertz range fields.
再次表明了我们已经知道的，50Hz的磁场是最有害的。但是，它再次承认，我们对低千赫兹范围的场了解不多。
The only mention is:
At a frequency of 20kHz, the flux density of the magnetic fields they generate can exceed the low action level and low exposure limit value but are unlikely to exceed the high action level and high exposure limit value (Guldiman and Meier, 2012). For industrial induction heaters, however, one third of the reported maximum flux densities measured at the workplace exceed the high action level in the revised Directive (Fig. 1B). Approximately half of these flux densities also exceed the limbs action level. With one exception, induction heaters where worker exposure exceeds the high action level operated in the range of 300 Hz to 30kHz.
唯一值得一提的是:
在20kHz频率下它们产生的磁场通量密度可以超过低作用水平和低暴露极限值，但不太可能超过高作用水平和高暴露极限值(Guldiman和Meier, 2012)。然而对于工业感应加热器，在工作场所测量的最大通量密度有三分之一超过修订指令中的高行动水平(图1B)。这些流量密度中约有一半也超过肢体活动水平。只有一个例外，感应加热器工作人员接触超过高动作水平，在300hz至30kHz的范围内工作。
Unfortunately, no publications were found with calculations of the currents or electric fields induced in the worker’s body by magnetic fields of induction heaters. It therefore remains to be seen whether the exposure limit values in the revised Directive may be exceeded.
不幸的是，还没有关于感应加热器磁场在工人体内产生的电流或电场计算的出版物。因此，是否会超过经修订的指示中的接触极限值仍有待观察。
But then again, biologically relevant induced voltage usually only occurs at >100kHz. So does a 20kHz field actually harm you as much, even if the induced current is high?
但是，生物学相关的感应电压通常只发生在>100kHz。那么，即使感应电流很高，20kHz的磁场也会对你造成同样大的伤害吗?
We need to look at more research.
我们需要更多的研究。
One research summary phamplet discussing Induction Cooktops emitting between 20kHz and 100kHz
一项研究总结称，电磁炉炉顶的辐射在20kHz至100kHz之间
http://www.inis.si/fileadmin/user_ulpoad/INIS/publikacije/2011_05_Kos_KIDS.pdf
Not that useful, but I'll list it for completeness sake.
不是很有用，但为了完整起见，我还是把它列出来。
Review of Induction Cooktops emitting at 20kHz
对感应炉灶面发出20kHz辐射的检讨
http://www.jmpee.org/JMPEE_PDFs/22-2_bl/JMPEE-Vol22-Pg63-Stuchly.pdf
Quote:The magnetic field strength at a distance of 0.3m ranges from 0.7 to 1.6 A/m (amperes per meter) and at a distance of 1m is less than 0.1 A/m.
At a distance of 0.1m exposures to a field strength up to approximately 10 A/m takes place.
引用:
0.3m处磁场强度为0.7 ~ 1.6 a /
安培/米)，1m处小于0.1 a /m。在0.1米的距离暴露场强度约为10 a /m发生。
The units which they are using here reflects induced current in our tissues.
他们在这里使用的单位反映了我们组织中的感应电流。
They quote a table of safety standards, of which:
他们引用了一个安全标准表，其中:
•American Council of Government Industrial Hygeine (1986): 1.64 A/m limit for 10-3,000kHz fields
美国政府工业卫生委员会(1986):10- 3000khz领域的1.64 A/m限制
•USSR (1976): 5 A/m limit for 60-1,500kHz fields苏联(1976):5 A/m限制60- 1500khz领域
Also, these recommendations apply to exposures of 8 to 24 hrs a day. So if you're comparing to the standards, standing 0.3m (1 foot) away from an induction cooker puts you below the limit. And I'm sure you won't be cooking for more than 30 mins a day in front of that thing (ideally even less).
此外这些建议适用于每天暴露8到24小时。所以如果你和标准相比站在离电磁炉0.3米(1英尺)远的地方你就低于标准。我敢肯定你每天在那东西前面做饭的时间不会超过30分钟(理想情况下甚至更少)。
The authors state:
As an alternative way of assessment, the magnetic fields produced by the stoves may be compared to the magnetic flux densities estimated to produce given current densities in peripheral regions of the head and heart.
According to the Bernhardt estimates, at the frequencies of operation of the stoves, the induced current densities are of the order of 10 µA/cm^2.
作者认为：
作为另一种评估方法，可以将炉子产生的磁场与估计在头部和心脏外围区域产生给定电流密度的磁通量密度进行比较。
根据Bernhardt的估计，在炉具操作的频率下，感应电流密度的数量级为10µA/cm^2。
The limit curve for the absence of detectable effects at these frequencies is at about 200 µA/cm^2, or the corresponding magnetic field strengh of about 160 A/m.
在这些频率下，没有可检测到的效应的极限曲线约为200µA/cm^2，或相应的磁场强度约为160 A/m。
This evaluation yields the same conclusion i.e. that harmful effects of exposure to the fields produced by induction stoves are not likely.
这一评估得出了同样的结论，即接触感应炉产生的磁场不太可能产生有害影响。
I couldn't find the Bernhardt paper, so I will have to take it on faith for now that they did their modelling correctly. It's a large margin of error we can afford (20x factor), but we should still exercise precaution.
我找不到伯恩哈特的论文，所以我现在只能相信他们的建模是正确的。这是我们可以承受的一个很大的误差幅度(20倍)，但我们仍然应该采取预防措施。
That said, the experimental evidence on rats seems to indicate that the effects are indeed minimal.
也就是说，在老鼠身上的实验证据似乎表明，这种效果确实是微乎其微的。
Another study on Induction Cookers
另一项关于电磁炉的研究
http://iopscience.iop.org/0031-9155/56/19/001/pdf/pmb11_19_001.pdf
Interesting:
有趣的是：
The pot size with respect to the cooking area also has a strong effect on the stray fields. We measured this effect by using pots with diameters of 15, 20 and 25 cm on the same (21 cm) cooking area, and the measured values at a 5 cm horizontal distance from the appliance were 4.5, 2.4 and 0.9 μT, respectively. A misalignment of the pot with respect to the centre of the cooking area increased the measured fields for the 20 and 25 cm pots by up to 20%, while the misalignment of the 15 cm pot did not result in a field increase.
相对于烹饪面积而言，锅的大小也对杂散场有很强的影响。我们用直径为15、20和25厘米的锅在相同的烹饪面积(21厘米)上测量了这一效应，在距离器具水平距离5厘米处的测量值分别为4.5、2.4和0.9 μT。锅相对于烹饪区域中心的偏差使20和25厘米的锅的测量面积增加了20%，而15厘米的锅的偏差并没有导致面积增加。
But again, we're seeing a low field of 0.9 μT at a 25cm distance, which is much lower than the 6+ μT fields used in the rat studies.
但同样，我们在25厘米的距离看到0.9 μT的低场，这比在大鼠研究中使用的6+ μT低得多。
If you look at Table 4, it's interesting to note that 105kHz fields produced less current than 35kHz fields.
如果你看表4，你会发现105kHz场产生的电流比35kHz场产生的电流要少。
eg: in a 26-week old fetus (which had the highest induced currents):
例如:在一个26周大的胎儿(其诱导电流最高):
35kHz field 35赫兹场：
•Whole Body (WB) current of 46 mA/m^2 (which is 4.6 µA/cm^2, which is below the 10 µA/cm^2 estimated by Bernhardt in the previous paper. So Bernhardt may actually be right)整体(WB)电流为46 mA/m^2(即4.6µA/cm^2)，低于Bernhardt在之前的论文中估计的10µA/cm^2。所以Bernhardt可能是对的)
•CNS 46 mA/m^2 (same as WB)
CNS 46 mA/m^2(与WB相同)
100kHz field 100赫兹场：
•WB of 15 mA/m^2
•CNS of 15 mA/m^2
Personally, I think that the 100kHz field is causing more heating, and less induced current. Heating can be harmful as well.
就我个人而言，我认为100kHz的磁场造成了更多的加热，和更少的感应电流。加热也可能有害。
But overall, I am again surprised by how the numbers are way below threshold ….
但总体而言，我再次惊讶于这些数字是如何远低于….的门槛
Personal Testing with Induction Cooktops电磁炉个人测试
Despite the claims above, I tested 3 different portable induction stoves, only to find huge ELF-EMF magnetic fields (<2,000Hz). We're talking >5mG fields a foot away from the cooker.
尽管有上述说法，我还是测试了3个不同的便携式感应炉，只发现了巨大的ELF-EMF磁场(< 2000hz)。我们说的是离炊具一英尺远的>5mG磁场。
Other testers (just search youtube) also find huge ELF-EMF magnetic fields, which are VERY harmful to any bio-form.
其他测试者(搜索youtube)也发现了巨大的ELF-EMF磁场，这对任何生物都是非常有害的。
I do not know at this point if it is possible to manufacture Induction Heating equipment that exclusively utilises EMF in the 25-100kHz range, but they are certainly not on the market as far as I am aware.
我不知道在这一点上，如果它是可能制造的感应加热设备，专门利用EMF在25-100kHz范围，但他们肯定没有在市场上，就我所知。
Conclusion for Now
结论（目前）
I will need to examine more research, but it looks promising that the low kilohertz range fields are a band which biology doesn't actually use for signalling. If that is true, then we have an EMF window that is usable for various applications like heating, and possibly short-range wireless communication (<1km).
我需要检查更多的研究，但看起来很有希望的是，低千赫兹范围的领域是一个频带，生物学实际上并不使用信号。如果这是真的，那么我们就有了一个EMF窗口，可以用于各种应用，比如加热，可能还有短距离无线通信(<1公里)。