Feychting M, Floderus B, Ahlbom A
Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
Cancer Causes Control. 2000 Feb;11(2):151-6. doi: 10.1023/a:1008922016813.
To test the hypothesis that parental occupational exposure to magnetic fields before conception and during pregnancy increases the risk of cancer in the offspring.
The study is designed as a cohort study based on a population of 235,635 children born shortly after two different censuses in Sweden. The children were followed from birth to 14 years and cases of cancer were identified in the Swedish cancer registry. The parents' occupational titles in the censuses were linked to a job-exposure matrix with information about magnetic field levels in different occupations. The cancer incidence among the exposed was compared to that among the unexposed using Cox proportional hazards modeling.
There was no association between childhood cancer and maternal occupational magnetic field exposure. Paternal exposure was associated with an increased risk of childhood leukemia, with a relative risk of 2.0 (95% CI 1.1-3.5) for exposures > or = 0.30 microT. A decreased risk was found for brain tumors (RR = 0.5; 95% CI 0.3-1.0).
The results do not support previous findings of an increased risk of childhood brain tumors associated with paternal occupational exposure to magnetic fields. The finding for childhood leukemia has to be interpreted with caution.
检验孕前及孕期父母职业暴露于磁场会增加子代患癌风险这一假设。
本研究设计为一项队列研究，基于瑞典两次不同人口普查后不久出生的235635名儿童群体。对这些儿童从出生追踪至14岁，并在瑞典癌症登记处确定癌症病例。人口普查中父母的职业头衔与一个工作暴露矩阵相关联，该矩阵包含不同职业的磁场水平信息。使用Cox比例风险模型比较暴露组与非暴露组的癌症发病率。
儿童癌症与母亲职业磁场暴露之间无关联。父亲暴露与儿童白血病风险增加相关，暴露≥0.30微特斯拉时相对风险为2.0（95%可信区间1.1 - 3.5）。发现脑肿瘤风险降低（相对风险 = 0.5；95%可信区间0.3 - 1.0）。
结果不支持先前关于父亲职业暴露于磁场会增加儿童脑肿瘤风险的研究发现。儿童白血病的这一发现必须谨慎解读。
