Prenatal serum thallium exposure and 36-month-old children's attention-deficit/hyperactivity disorder symptoms: Ma'anshan birth cohort study

Highlight：通过测量铊水平和评估儿童ADHD症状，发现铊暴露增加儿童ADHD症状发生风险，为孕期铊暴露的神经发育毒性提供依据。

Abstract

Thallium(Tl)is a highly toxic heavy metal that has been suggested to be responsible for oxidative stress and mitochondrial dysfunction. However, few studies have focused on the relationship of prenatal Tl exposure with children’s neurobehavioural development. The purpose of our study was to investigate the association between prenatal Tl exposure and attention-deficit/hyperactivity disorder(ADHD)symptoms in 36-month-old children. We used data from 28 mother-newborn pairs from the Ma’anshan Birth Cohort Study(MABC); serum Tl concentration was assessed in the first, second and third trimesters of pregnancy as well as in the umbilical cord blood. We assessed ADHD symptoms in the children using the Chinese version of the Conners abbreviated symptom questionnaire(C-ASQ). The adjusted odds ratio(OR)for the risk of ADHD symptoms was 2.00 [95% confidence interval(CI): 1.20, 3.32] and 2.08(95%CI: 1.26, 3.43)for the third(60.25-75.21 ng/L)and fourth quartiles of serum Tl(＞5.21 ng/L), respectively, in the second trimester of pregnancy, in comparison with the first quartile of serum Tl(＜0.86 ng/L). The risk of ADHD symptoms was elevated among boys exposed to the fourth quartile of serum Tl in the second trimester of pregnancy(adjusted OR 2.08, 95%CI: 1.13, 3.83). Our results demonstrated that high levels of Tl exposure in the second trimester of pregnancy were related to a higher risk of ADHD symptoms in 36-month-old children, and the association of higher serum Tl exposure in the second trimester with ADHD symptoms was only found in boys.

Tong J, Liang CM, Huang K, Xiang HY, Qi J, Feng LL, Lai YP, Shao SS, Wu XY, Tao FB*. Prenatal serum thallium exposure and 36-month-old children's attention-deficit/hyperactivity disorder symptoms: Ma'anshan birth cohort study. Chemosphere, 2020, 244:125499.