Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
Center of Neurodevelopmental Disorders (KIND), Department of Women's and Children's Health, Centre for Psychiatry Research, Karolinska Institutet & Region Stockholm, Stockholm, Sweden.
Environ Res. 2024 Dec 15;263(Pt 2):120123. doi: 10.1016/j.envres.2024.120123. Epub 2024 Oct 9.
Early-life lead exposure affects cognitive development and emerging evidence suggests similar effects of cadmium and fluoride.
To assess the impact of gestational and childhood exposure to lead, cadmium, and fluoride on cognitive abilities and behavioral and social communication problems.
We studied 470 pregnant women (gestational week 29) and their 4-year-old children from the NICE cohort in northern Sweden. Concentrations of erythrocyte lead and cadmium and urinary cadmium were measured using inductively coupled plasma mass spectrometry and urinary fluoride with an ion-selective electrode. Urinary concentrations were specific-gravity adjusted. Associations of log-transformed exposure concentrations with cognitive abilities (full-scale IQ and verbal comprehension by Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition), behavioral problems (Child Behavior Checklist), and social communication (Social Responsiveness Scale-Second Edition) were evaluated with multivariable-adjusted linear regression analysis.
Both gestational and cord erythrocyte lead concentrations were non-significantly inversely associated with child cognitive abilities (full-scale IQ: B [95%CI]: -1.2 [-2.9, 0.5] and -1.6 [-3.7, 0.4], respectively; per doubling of exposure). Similarly, both gestational and child urinary cadmium were inversely associated with cognitive abilities (full-scale IQ: -1.1 [-2.5, 0.3] and -1.1 [-2.5, 0.4], verbal comprehension: -1.2 [-3.1, 0.6] and -1.4 [-3.4, 0.6], respectively). Urinary fluoride concentrations showed no association with cognitive abilities. However, gestational fluoride was associated with increasing externalizing problems (0.9 [-0.3, 2.0]) and ADHD raw scores (0.3 [0.0, 0.6]). Childhood erythrocyte lead and urinary cadmium were non-significantly associated with increased behavioral problems (lead with total problems: 1.2 [-0.4, 2.9] and internalizing problems: 1.5 [-0.4, 3.4]; cadmium with externalizing problems: 1.1 [-0.2, 2.4]).
Despite non-significant associations, both lead and cadmium exposure showed consistent inverse associations with cognitive abilities at 4 years, whereas associations with behavioral problems were less conclusive, especially for cadmium. Results on fluoride indicated association with externalizing problems, including ADHD, but prevalence of behavioral problems was low, increasing uncertainty.
早期生活中的铅暴露会影响认知发育，新出现的证据表明，镉和氟化物也有类似的影响。
评估妊娠期和儿童期铅、镉和氟暴露对认知能力以及行为和社会交流问题的影响。
我们研究了来自瑞典北部 NICE 队列的 470 名孕妇（妊娠 29 周）及其 4 岁的儿童。使用电感耦合等离子体质谱法测量红细胞中的铅和镉浓度，使用离子选择性电极测量尿中的氟浓度。尿浓度经过比重校正。使用多变量调整线性回归分析评估经对数转换后的暴露浓度与认知能力（韦氏学前和小学智力量表第四版的全量表智商和言语理解）、行为问题（儿童行为检查表）和社会交流（社会反应量表第二版）之间的关联。
脐带血和胎血中的铅浓度与儿童的认知能力呈负相关（全量表智商：B[95%CI]：-1.2[-2.9，0.5]和-1.6[-3.7，0.4]，分别；暴露每增加一倍），但无统计学意义。同样，脐带血和儿童尿中的镉浓度与认知能力呈负相关（全量表智商：-1.1[-2.5，0.3]和-1.1[-2.5，0.4]，言语理解：-1.2[-3.1，0.6]和-1.4[-3.4，0.6]，分别）。尿氟浓度与认知能力无关联。然而，妊娠期氟化物与外化问题增加有关（0.9[-0.3，2.0]）和 ADHD 原始分数增加有关（0.3[0.0，0.6]）。儿童期红细胞铅和尿镉与行为问题增加呈负相关（铅与总问题：1.2[-0.4，2.9]和内化问题：1.5[-0.4，3.4]；镉与外化问题：1.1[-0.2，2.4]）。
尽管无统计学意义，但铅和镉暴露均与 4 岁时的认知能力呈一致的负相关，而与行为问题的关联则不太明确，尤其是与镉的关联。关于氟化物的结果表明与外化问题有关，包括 ADHD，但行为问题的流行率较低，增加了不确定性。
