Green L M, Miller A B, Agnew D A, Greenberg M L, Li J, Villeneuve P J, Tibshirani R
Department of Public Health Sciences, University of Toronto, Ontario, Canada.
Cancer Causes Control. 1999 Jun;10(3):233-43. doi: 10.1023/a:1008919408855.
To evaluate the risk of childhood leukemia in relation to residential electric and magnetic field (EMF) exposures.
A case control study based on 88 cases and 133 controls used different assessment methods to determine EMF exposure in the child's current residence. Cases comprised incident leukemias diagnosed at 0-14 years of age between 1985-1993 from a larger study in southern Ontario; population controls were individually matched to the cases by age and sex. Exposure was measured by a personal monitoring device worn by the child during usual activities at home, by point-in-time measurements in three rooms and according to wire code assigned to the child's residence.
An association between magnetic field exposures as measured with the personal monitor and increased risk of leukemia was observed. The risk was more pronounced for those children diagnosed at less than 6 years of age and those with acute lymphoblastic leukemia. Risk estimates associated with magnetic fields tended to increase after adjusting for power consumption and potential confounders with significant odds ratios (OR) (OR: 4.5, 95% confidence interval (CI): 1.3-15.9) observed for exposures > or = 0.14 microTesla (microT). For the most part point-in-time measurements of magnetic fields were associated with non-significant elevations in risk which were generally compatible with previous research. Residential proximity to power lines having a high current configuration was not associated with increased risk of leukemia. Exposures to electric fields as measured by personal monitoring were associated with a decreased leukemia risk.
The findings relating to magnetic field exposures directly measured by personal monitoring support an association with the risk of childhood leukemia. As exposure assessment is refined, the possible role of magnetic fields in the etiology of childhood leukemia becomes more evident.
评估儿童白血病与居住环境中电场和磁场（EMF）暴露之间的风险关系。
一项病例对照研究，基于88例病例和133例对照，采用不同评估方法确定儿童当前居住地的EMF暴露情况。病例包括1985 - 1993年间在安大略省南部一项更大规模研究中确诊的0至14岁的新发白血病患者；人群对照按年龄和性别与病例进行个体匹配。暴露情况通过儿童在家中日常活动时佩戴的个人监测设备、三个房间的即时测量以及根据分配给儿童住所的电线代码来测量。
观察到个人监测测量的磁场暴露与白血病风险增加之间存在关联。对于那些6岁以下确诊的儿童以及急性淋巴细胞白血病患者，这种风险更为明显。在调整了电力消耗和潜在混杂因素后，与磁场相关的风险估计值往往会增加，对于暴露≥0.14微特斯拉（μT）的情况，观察到显著的优势比（OR）（OR：4.5，95%置信区间（CI）：1.3 - 15.9）。在大多数情况下，磁场的即时测量与风险的非显著升高相关，这通常与先前的研究结果相符。居住在高电流配置的输电线附近与白血病风险增加无关。通过个人监测测量的电场暴露与白血病风险降低相关。
与通过个人监测直接测量的磁场暴露相关的研究结果支持其与儿童白血病风险之间存在关联。随着暴露评估的完善，磁场在儿童白血病病因学中的可能作用变得更加明显。
