Center for Environmental Research & Children's Health (CERCH), School of Public Health, University of California, 1995 University Avenue, Suite 265, Berkeley, CA, 94720-7392, USA.
Department of Laboratory Medicine, University of Milano-Bicocca and Hospital of Desio, Desio-Milano, Italy.
Environ Health. 2018 Feb 27;17(1):22. doi: 10.1186/s12940-018-0365-2.
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a toxic environmental contaminant that can bioaccumulate in humans, cross the placenta, and cause immunological effects in children, including altering their risk of developing allergies. On July 10, 1976, a chemical explosion in Seveso, Italy, exposed nearby residents to a high amount of TCDD. In 1996, the Seveso Women's Health Study (SWHS) was established to study the effects of TCDD on women's health. Using data from the Seveso Second Generation Health Study, we aim to examine the effect of prenatal exposure to TCDD on the risk of atopic conditions in SWHS children born after the explosion.
Individual-level TCDD was measured in maternal serum collected soon after the accident. In 2014, we initiated the Seveso Second Generation Health Study to follow-up the children of the SWHS cohort who were born after the explosion or who were exposed in utero to TCDD. We enrolled 677 children, and cases of atopic conditions, including eczema, asthma, and hay fever, were identified by self-report during personal interviews with the mothers and children. Log-binomial and Poisson regressions were used to determine the association between prenatal TCDD and atopic conditions.
A 10-fold increase in 1976 maternal serum TCDD (logTCDD) was not significantly associated with asthma (adjusted relative risk (RR) = 0.93; 95% CI: 0.61, 1.40) or hay fever (adjusted RR = 0.99; 95% CI: 0.76, 1.27), but was significantly inversely associated with eczema (adjusted RR = 0.63; 95% CI: 0.40, 0.99). Maternal TCDD estimated at pregnancy was not significantly associated with eczema, asthma, or hay fever. There was no strong evidence of effect modification by child sex.
Our results suggest that maternal serum TCDD near the time of explosion is associated with lower risk of eczema, which supports other evidence pointing to the dysregulated immune effects of TCDD.
2,3,7,8-四氯二苯并对二恶英（TCDD）是一种有毒的环境污染物，可在人体内生物累积，穿过胎盘，并对儿童产生免疫影响，包括改变他们患过敏的风险。1976 年 7 月 10 日，意大利塞韦索发生化学爆炸，附近居民暴露于高浓度的 TCDD 中。1996 年，塞韦索妇女健康研究（SWHS）成立，旨在研究 TCDD 对妇女健康的影响。我们利用来自塞韦索第二代健康研究的数据，旨在研究爆炸后出生的 SWHS 儿童在子宫内接触 TCDD 对特应性疾病风险的影响。
在事故发生后不久采集的母亲血清中测量个体水平的 TCDD。2014 年，我们启动了塞韦索第二代健康研究，以随访 SWHS 队列中爆炸后出生或在子宫内接触 TCDD 的儿童。我们招募了 677 名儿童，并通过母亲和儿童的个人访谈，通过自我报告确定特应性疾病（包括湿疹、哮喘和花粉热）的病例。使用对数二项式和泊松回归来确定产前 TCDD 与特应性疾病之间的关联。
1976 年母亲血清 TCDD（logTCDD）增加 10 倍与哮喘（调整后相对风险（RR）=0.93；95%CI：0.61，1.40）或花粉热（调整后 RR=0.99；95%CI：0.76，1.27）无关，但与湿疹（调整后 RR=0.63；95%CI：0.40，0.99）显著负相关。妊娠时估计的母体 TCDD 与湿疹、哮喘或花粉热无关。没有强有力的证据表明性别是影响修饰因素。
我们的结果表明，爆炸时母亲血清 TCDD 与湿疹风险降低有关，这支持了其他指向 TCDD 免疫调节作用失调的证据。
