It is important to study the relationship between extremely low‐frequency magnetic fields (ELF‐MFs) and childhood leukemia, particularly in locations with a high incidence of this neoplasm in children and an elevated exposure to ELF‐MF, such as Mexico City. The aim was to investigate the association between ELF‐MF exposure and the risk of B‐lineage acute lymphoblastic leukemia (B‐ALL). A case–control study was conducted in Mexico City during the period from 2010 to 2011. Residential 24‐h ELF‐MF measurements were obtained for 290 incident B‐ALL patients and 407 controls, aged less than 16 years. Controls were frequency‐matched by sex, age (±18 months), and health institution. The adjusted odds ratios (aOR) and 95% confidence intervals (CIs) were calculated. ELF‐MF exposure at <0.2 μT was used to define the reference group. ELF‐MF exposure at ≥0.3 μT was observed in 11.3% of the controls. Different ELF‐MF intensity cutoff values were used to define the highest exposure category; the highest exposure category for each cutoff value was associated with an increased risk of B‐ALL compared with the corresponding lower exposure categories. The aORs were as follows: ≥0.2 μT = 1.26 (95% CI: 0.84–1.89); ≥0.3 μT = 1.53 (95% CI: 0.95–2.48); ≥0.4 μT = 1.87 (95% CI: 1.04–3.35); ≥0.5 μT = 1.80 (95% CI 0.95–3.44); ≥0.6 μT = 2.32 (95% CI: 1.10–4.93). ELF‐MF exposure as a continuous variable (per 0.2 μT intervals) was associated with B‐ALL risk (aOR = 1.06; 95% CI: 1.01–1.12). In the present study, the proportion of children exposed to ≥0.3 μT is among the highest reported worldwide. Additionally, an ELF‐MF exposure ≥0.4 μT may be associated with the risk of B‐ALL. Bioelectromagnetics. © 2020 Bioelectromagnetics Society

中文翻译：

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极低频磁场和儿童 B 谱系急性淋巴细胞白血病的风险，在一个白血病发病率高且暴露于极低频磁场的城市中。

研究极低频磁场 (ELF-MF) 与儿童白血病之间的关系非常重要，特别是在儿童这种肿瘤高发和极低频磁场暴露程度高的地区，如墨西哥城。目的是研究 ELF-MF 暴露与 B 系急性淋巴细胞白血病 (B-ALL) 风险之间的关联。2010 年至 2011 年期间在墨西哥城进行了一项病例对照研究。获得了 290 名年龄小于 16 岁的 B-ALL 患者和 407 名对照的住宅 24 小时 ELF-MF 测量值。对照按性别、年龄（±18 个月）和卫生机构频率匹配。计算调整后的优势比 (aOR) 和 95% 置信区间 (CI)。使用 <0.2 μT 的 ELF-MF 暴露来定义参考组。ELF-MF 暴露在 ≥ 0。在 11.3% 的对照中观察到 3 μT。使用不同的 ELF-MF 强度截止值来定义最高暴露类别；与相应的较低暴露类别相比，每个临界值的最高暴露类别与 B-ALL 风险增加相关。aOR 如下：≥0.2 μT = 1.26（95% CI：0.84–1.89）；≥0.3 μT = 1.53（95% CI：0.95–2.48）；≥0.4 μT = 1.87（95% CI：1.04–3.35）；≥0.5 μT = 1.80（95% CI 0.95–3.44）；≥0.6 μT = 2.32（95% CI：1.10–4.93）。ELF-MF 暴露作为连续变量（每 0.2 μT 间隔）与 B-ALL 风险相关（aOR = 1.06；95% CI：1.01–1.12）。在本研究中，暴露于≥0.3 μT 的儿童比例是全球报告的最高水平之一。此外，ELF-MF 暴露≥0.4 μT 可能与 B-ALL 风险相关。生物电磁学。