Urinary arsenic speciation, methylation capacity, and growth outcomes in longitudinal mother-child pairs across pregnancy to preschool age: A single prenatal spot measurement poorly predicts children's arsenic profiles and growth.

A single prenatal urinary arsenic measurement poorly predicts arsenic profiles and growth outcomes in children aged 3-5 years in a high seafood-consuming population.

• Why it matters: Understanding arsenic exposure during pregnancy and early childhood is crucial because dietary sources like seafood and rice influence arsenic forms, complicating exposure assessment and health risk evaluation.
• What they did: The study analyzed five urinary arsenic species in 200 mother-child pairs at two time points—during pregnancy and preschool age—using HPLC-ICP-MS, and examined associations with growth using regression models.
• The result: Findings show that postnatal dietary environment, rather than prenatal arsenic speciation, primarily determines child arsenic burden, and prenatal measurements alone do not predict growth or arsenic profiles at preschool age.