Endocrinol Metab.  2022 Dec;37(6):819-829. 10.3803/EnM.2022.1598.

Prenatal Exposure to Per- and Polyfluoroalkyl Substances, Maternal Thyroid Dysfunction, and Child Autism Spectrum Disorder

• Shin HM
• Oh J
• J. Schmidt R
• N. Pearce E

• KMID: 2537282
• DOI: http://doi.org/10.3803/EnM.2022.1598

Abstract

Autism spectrum disorder (ASD), with its high economic and societal costs, is a growing public health concern whose prevalence has risen steadily over the last two decades. Although actual increased incidence versus improved diagnosis remains controversial, the increased prevalence of ASD suggests non-inherited factors as likely contributors. There is increasing epidemiologic evidence that abnormal maternal thyroid function during pregnancy is associated with increased risk of child ASD and other neurodevelopmental disorders. Prenatal exposure to endocrine-disrupting chemicals such as per- and polyfluoroalkyl substances (PFAS) is known to disrupt thyroid function and can affect early brain development; thus, thyroid dysfunction is hypothesized to mediate this relationship. The concept of a potential pathway from prenatal PFAS exposure through thyroid dysfunction to ASD etiology is not new; however, the extant literature on this topic is scant. The aim of this review is to evaluate and summarize reports with regard to potential mechanisms in this pathway.

Keyword

Antibodies; Autism spectrum disorder; Endocrine disrupting chemicals; Environmental exposure; Pregnancy; Thyroid

Figure

• 

  Fig. 1. Per- and polyfluoroalkyl substances (PFAS) are known to disrupt immune systems and the hypothalamus-pituitary-thyroid axis, either alone or in combination. Thyroid peroxidase antibody (TPO-Ab) and thyroglobulin antibody (Tg-Ab), which are common in autoimmune thyroid disorders, may cause thyroid dysfunction. Primary and secondary pathways discussed in this review are represented in blue and magenta, respectively. TSH, thyroid stimulating hormone; T3, triiodothyronine; T4, thyroxine.

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