Perinatal Exposure to Environmental Phthalate and the Cognitive Development of 6-Month-Old Infants (MOCEH Study)

Abstract

PP-31-073 Background/Aims: The relationship between the maternal urinary concentrations of phthalate metabolites during pregnancy and the children's intellectual development was explored. Methods: Mono-2-ethylhexyl phthalate (MEHHP) and mono (2-ethyl-5-oxohexyl) phthalate (MEOHP), both metabolites of di (2-ethylhexyl) phthalate (DEHP), and mono-n-butyl phthalate (MBP), a metabolite of dibutyl phthalate (DBP), were measured in urine samples of 236 mothers at first trimester and 470 mothers at mid trimester of pregnancy. The cognitive developmental status of the 6-month-old infants was assessed using Korean Bayley scales of Infant development-second edition. Results: The mean concentrations of MEHHP, MEOHP, and MBP were 12.6 μg/L (SD = 13.8, range: 0.25–97.9), 13.3 μg/L (SD = 17.8, range: 0.28–193.9), and 35.3 μg/L (SD = 66.1, range: 0.22–911.9), respectively, at first trimester and 15.4 μg/L (SD = 23.0, range: 0.25–262.7), 18.9 μg/L (SD = 29.7, range: 0.28–303.6), and 35.5 μg/L (SD = 56.9, range: 0.22–528.1), respectively, at mid trimester. After adjusting for demographic and developmental covariates, the cognitive quotient and motor quotient were negatively associated with DEHP metabolites, but not with DBP metabolites concentrations of mothers at first trimester. We also found a tendency for negative relationship between the cognitive quotient and motor quotient and DEHP metabolites, but not with DBP metabolites concentrations of mothers at mid trimester. After controlling for maternal IQ, the tendency for inverse relationship between the DEHP metabolites at mid trimester and the cognitive quotient and motor quotient was still observed. Conclusion: This study observed a tendency for an inverse relationship between phthalate metabolites in urine of mothers during pregnancy and the infant developmental quotient at 6 month of the offspring.