Olsen J H, Nielsen A, Schulgen G
Danish Cancer Society, Division for Cancer Epidemiology, Copenhagen.
BMJ. 1993 Oct 9;307(6909):891-5. doi: 10.1136/bmj.307.6909.891.
To investigate whether residence before and after birth near 50 Hz high voltage installations increases a child's risk of cancer and whether risk correlates with the strength of the magnetic field.
A population based case-control study.
Denmark.
1707 children under the age of 15 with leukaemia, tumour of the central nervous system, or malignant lymphoma diagnosed in 1968-86 and 4788 children taken from the central population register.
Proximity before and after birth to existing or former 50-400 kV electrical transmission connections and substations and associated historical electromagnetic fields calculated on the basis of current load on line, phase ordering of line, and distance from the dwelling.
A significant association was seen between all major types of childhood cancer combined and exposure to magnetic fields from high voltage installations of > or = 0.4 microT (odds ratio 5.6). At > or = 0.25 microT no significant association was seen (odds ratio 1.5). A possible association was also seen with cases of Hodgkin's disease separately at > or = 0.1 microT.
On the basis these results and additional descriptive data on electricity consumption and incidence of childhood cancer in Denmark since the 1940s it was concluded that the proportion of childhood cancer possibly caused by 50 Hz electromagnetic fields must be small.
调查出生前后居住在50赫兹高压设施附近是否会增加儿童患癌症的风险，以及风险是否与磁场强度相关。
一项基于人群的病例对照研究。
丹麦。
1968年至1986年期间诊断出患有白血病、中枢神经系统肿瘤或恶性淋巴瘤的1707名15岁以下儿童，以及从中央人口登记处选取的4788名儿童。
出生前后与现有或以前的50 - 400千伏输电线路和变电站的距离，以及根据线路当前负荷、线路相序和住所距离计算出的相关历史电磁场。
所有主要类型的儿童癌症合并起来与暴露于强度大于或等于0.4微特斯拉的高压设施磁场之间存在显著关联（优势比为5.6）。在强度大于或等于0.25微特斯拉时未发现显著关联（优势比为1.5）。单独来看，在强度大于或等于0.1微特斯拉时，霍奇金病病例也可能存在关联。
基于这些结果以及自20世纪40年代以来丹麦关于电力消耗和儿童癌症发病率的其他描述性数据，得出的结论是，50赫兹电磁场可能导致的儿童癌症比例必定很小。
