Gestational triclosan exposure and its effects on childneurodevelopment - A systematic review

Triclosan (TCS) is a lipophilic antimicrobial agent present in commercial and healthcare products. Despite its beneficial properties, TCS disrupts thyroid hormone homeostasis and may be linked to metabolic disorders, cardiotoxicity, and increased cancer risk. Evidence on prenatal TCS exposure and adverse neurobehavioral outcomes is limited. This systematic review aimed to verify whether prenatal exposure to TCS is associated with neurobehavioral impairments. Observational studies with pregnant women exposed to TCS during pregnancy were included. The MEDLINE, EMBASE, Scopus, Web of Science, and LILACS databases were searched for studies up to February 27, 2024. Titles and abstracts were first screened, followed by full-text readings by two independent reviewers. Data extraction was performed independently, with conflicts resolved by consensus with a third reviewer. The included studies were assessed using an adapted Downs and Black tool and qualitatively synthesized. Certainty of evidence was assessed by GRADE. The study protocol was registered with PROSPERO (CRD42024526426). Among 17 studies, 14 cohort studies met the inclusion criteria. The sample size ranged from 193 to 794 pairs of pregnant women and children. Exposure to TCS throughout pregnancy resulted in median concentrations from 0.40 ng/mL to 28.2 ng/mL. Four studies suggested a potential association between prenatal TCS exposure and neurodevelopmental deficits, such as externalizing problems, attention issues, hyperactivity, somatization, emotional symptoms, social awareness, and communication; in contrast, eight studies found no significant effect. The studies had low certainty of evidence. Considering the heterogeneity and confounding factors, further investigation is required to confirm that prenatal TCS exposure leads to neurobehavioral disorders.