Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China; MOE Key Laboratory of Population Health Across Life Cycle, Hefei, Anhui, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Hefei, Anhui, China; Anhui Provincial Key Laboratory of Population Health and Aristogenics, Hefei, Anhui, China.
MOE Key Laboratory of Population Health Across Life Cycle, Hefei, Anhui, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Hefei, Anhui, China; Anhui Provincial Key Laboratory of Population Health and Aristogenics, Hefei, Anhui, China.
Environ Pollut. 2022 Jan 15;293:118545. doi: 10.1016/j.envpol.2021.118545. Epub 2021 Nov 18.
Thallium, a highly toxic heavy metal and priority pollutant, has been widely reported to cause neurodevelopmental toxicity in animals. However, accessible epidemiological studies concerning the neurodevelopmental toxicity of early-life thallium exposure in humans are limited. In a prospective birth cohort including 2164 mother-child pairs, we explored the effect of prenatal serum thallium exposure on cognitive development among preschool-aged children born in Ma'anshan, Anhui, China. Serum thallium concentrations were measured in the first trimester, second trimester, third trimester, and cord blood by inductively coupled plasma mass spectrometry (ICP-MS). Child cognitive development was appraised by the Chinese version of the Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition (WPPSI-IV) at 4.5 years old. Multiple informants generalized estimating equations (GEEs) were fit to jointly estimate the association between the four repeated measurements of thallium concentrations and the preschool-aged children's cognitive test scores. After adjusting for potential confounders, the visual spatial index (VSI) was 1.45 points lower in the highest tertile of serum thallium during the first trimester than in the lowest tertile (p for trend = 0.04). Moreover, children in the highest tertile of serum thallium during the third trimester had a significantly lower full-scale intelligence quotient (FSIQ) (β = -1.51, 95% CI: -2.68, -0.35), VSI (β = -1.79, 95% CI: -3.16, -0.42), fluid reasoning index (FRI) (β = -1.41, 95% CI: -2.73, -0.10), and processing speed index (PSI) (β = -1.47, 95% CI: -2.71, -0.24) scores than the children in the lowest tertile. When performing stratified analysis by child sex, the associations of first- and third-trimester thallium concentrations with cognitive test scores were more prominent in boys than in girls. Our findings revealed that maternal serum thallium exposure during the first and third trimesters, but not other periods, had detrimental effects on preschoolers' cognitive development, and these effects showed sex differences.
铊是一种毒性很强的重金属，也是优先污染物，已广泛报道其对动物具有神经发育毒性。然而，有关人类生命早期铊暴露的神经发育毒性的可获取的流行病学研究是有限的。在一项包括 2164 对母婴的前瞻性出生队列研究中，我们探讨了产前血清铊暴露对中国安徽马鞍山出生的学龄前儿童认知发育的影响。通过电感耦合等离子体质谱法（ICP-MS）测量了妊娠早期、妊娠中期、妊娠晚期和脐带血中的血清铊浓度。在 4.5 岁时，使用中国版韦氏学前和小学智力量表第四版（WPPSI-IV）评估儿童的认知发育。采用多变量广义估计方程（GEE）联合评估四个重复测量的血清铊浓度与学龄前儿童认知测试得分之间的关联。在调整了潜在混杂因素后，妊娠早期血清铊浓度最高 tertile 的儿童的视觉空间指数（VSI）比最低 tertile 低 1.45 分（趋势 P 值=0.04）。此外，妊娠晚期血清铊浓度最高 tertile 的儿童的全量表智商（FSIQ）（β=-1.51，95%CI：-2.68，-0.35）、VSI（β=-1.79，95%CI：-3.16，-0.42）、流体推理指数（FRI）（β=-1.41，95%CI：-2.73，-0.10）和加工速度指数（PSI）（β=-1.47，95%CI：-2.71，-0.24）显著低于最低 tertile 的儿童。按儿童性别进行分层分析时，妊娠早期和妊娠晚期的血清铊浓度与认知测试得分的关联在男孩中比在女孩中更为显著。我们的研究结果表明，妊娠早期和妊娠晚期的母体血清铊暴露对学龄前儿童的认知发育有不良影响，而其他时期没有，这些影响存在性别差异。
