IEEE Eng Med Biol Mag. 2000 Jan-Feb;19(1):131-7.
In recent years concerns have been raised about the biological effects of exposure to electric and magnetic fields at extremely low frequencies (ELF), particularly those associated with the distribution and utilization of electric power. In 1989, the Institute of Electrical and Electronics Engineers (IEEE) issued an "Entity Position Statement" which stated that "there is not enough relevant scientific data to establish whether common exposure to power-frequency fields should be considered a health hazard" and that "there is general agreement that more research is needed to define safe limits of human exposure to power-frequency fields." After examination of relevant research reports published during the last ten years, COMAR concludes that it is highly unlikely that health problems can be associated with average 24-hour field exposure to power frequency magnetic fields of less than 1 microT (10 mG). Good laboratory evidence shows that magnetic fields 100 to 10,000 times higher than this level, either ELF sinusoidal or pulsed, can induce a variety of biological effects, including beneficial health effects such as bone or tissue healing. Many of the reports of effects of weaker fields should be considered preliminary, as some observations have not been reproduced in different laboratories, while others, observed in cells, have not been clearly connected to effects in intact animals. Also, the means of interaction of low-level ELF fields with cells, tissues or laboratory animals is not fully understood; therefore the health impacts of such weak fields on intact animals and humans, if any, cannot be predicted or explained. Further research is needed to confirm or negate reports of effects of weak fields, and to determine mechanisms and relevance of these effects to actual health hazards. Continued study in this complicated area will enhance our understanding of biological systems, as well as help identify levels and types of ELF exposure that may be deleterious to human health.
近年来，人们对暴露于极低频（ELF）电场和磁场的生物学效应表示关注，尤其是与电力的分配和使用相关的效应。1989年，电气和电子工程师协会（IEEE）发布了一份“实体立场声明”，指出“没有足够的相关科学数据来确定一般暴露于工频电场是否应被视为健康危害”，并且“人们普遍认为需要更多的研究来确定人类暴露于工频电场的安全限值”。在审查了过去十年发表的相关研究报告后，COMAR得出结论，平均24小时暴露于小于1微特斯拉（10毫高斯）的工频磁场中，极不可能与健康问题相关。良好的实验室证据表明，比该水平高100至10000倍的磁场，无论是极低频正弦波还是脉冲磁场，都能诱发多种生物学效应，包括有益的健康效应，如骨骼或组织愈合。许多关于较弱磁场效应的报告应被视为初步的，因为一些观察结果在不同实验室中未得到重现，而另一些在细胞中观察到的结果，尚未与完整动物中的效应明确关联。此外，低水平极低频磁场与细胞、组织或实验动物的相互作用方式尚未完全了解；因此，这种弱磁场对完整动物和人类的健康影响（如果有的话）无法预测或解释。需要进一步的研究来证实或否定关于弱磁场效应的报告，并确定这些效应的机制及其与实际健康危害的相关性。在这个复杂领域的持续研究将增进我们对生物系统的理解，并有助于确定可能对人类健康有害的极低频暴露水平和类型。
