54 - The Effect of Early Life Exposure to Emergent Environmental Pollutants on Child Development: a Cohort Study Based on Taiwan Southern Human Milk Bank

Publication Number: 4053.54

Yung-Chieh Lin, National Cheng Kung University, Tainan, Tainan, Taiwan (Republic of China); Wei-Hsiang Chang, National Cheng Kung University, Tainan, Tainan, Taiwan (Republic of China); Po-Chin Huang, National Health Reseach Institutes, Zhunan, Miaoli, Taiwan (Republic of China)

Background: Phthalate esters (PAE) and their substitutes are endocrine-disrupting chemicals linked to adverse health outcomes, particularly in pregnant women and infants.

Objective: This longitudinal study quantified PAE metabolites in maternal and infant exposure to PAE through blood, urine, and human milk samples collected from pregnancy through early childhood, and evaluated potential impacts on infant health, hormonal systems, and neurodevelopment.

Design/Methods: This 4-year prospective cohort study (2022-2025) recruited 600 pregnant participants. Maternal blood, infant urine, maternal urine, and human milk samples were collected and analyzed. Maternal blood was analyzed for thyroid function tests (TFT). PAE metabolites concentrations were quantified at the Taiwan National Health Research Institutes. PAE metabolites include Mono-methyl phthalate (MMP), Mono-ethyl phthalate (MEP), Mono-isobutyl phthalate (MiBP), Mono-n-butyl phthalate (MnBP), Mono-benzyl phthalate(MBzP), Mono-(2-ethylhexyl) phthalate (MEHP); Mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), Mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), Mono-carboxy-octyl phthalate (MECPP), Mono-cumyl phthalate (MCMHP), and Mono-isononyl phthalate (MiNP). Demographic and clinical data were collected.

Results: Over 3.5 years, 557 mothers and 383 infants were enrolled. Biological samples included urine from 281 mothers and 341 infants, serial human milk from 314 mothers, and TFT from 363 mothers and 382 infants. Perinatal urine phthalate metabolite concentrations were analyzed. Most plasticizers were detected in >90% of human milk samples with significant variability. No statistically significant correlations were found between urine phthalate metabolites and infant TSH at birth (all p > 0.05). However, higher concentrations of MECPP and MCMHP in maternal urine were associated with lower free T4 levels.

Conclusion(s): his cohort study demonstrates comparable urine PAE metabolite levels between infants and mothers, with occasional higher infant MEHP levels suggesting transplacental and lactational transfer. These findings underscore the need for continued vigilance regarding phthalate exposure during pregnancy and lactation, and highlight the importance of long-term follow-up to assess potential health impacts.

Demographic data of infant-mother dyads


Pearson Correlation between Phthalate Metabolites in Breast Milk and Urine of Mother
(A: Within Four Months Postpartum; B: Six to Eight Months Postpartum); MMP: Mono-methyl phthalate; MEP: Mono-ethyl phthalate; MiBP: Mono-isobutyl phthalate; MnBP: Mono-n-butyl phthalate; MBzP: Mono-benzyl phthalate; MEHP: Mono-(2-ethylhexyl) phthalate; MEHHP: Mono-(2-ethyl-5-hydroxyhexyl) phthalate; MEOHP: Mono-(2-ethyl-5-oxohexyl) phthalate; MECPP Mono-carboxy-octyl phthalate; MCMHP: Mono-cumyl phthalate; MiNP: Mono-isononyl phthalate


Distribution of Phthalate Metabolite Concentrations in Urine of Infants
MMP: Mono-methyl phthalate; MEP: Mono-ethyl phthalate; MiBP: Mono-isobutyl phthalate; MnBP: Mono-n-butyl phthalate; MBzP: Mono-benzyl phthalate; MEHP: Mono-(2-ethylhexyl) phthalate; MEHHP: Mono-(2-ethyl-5-hydroxyhexyl) phthalate; MEOHP: Mono-(2-ethyl-5-oxohexyl) phthalate; MECPP Mono-carboxy-octyl phthalate; MCMHP: Mono-cumyl phthalate; MiNP: Mono-isononyl phthalate