Nonylphenol in pregnant women and their matching fetuses: Placental transfer and potential risks of infants

• Published in: Environmental research 2014-10, Vol.134, p.143-148
• Main Authors: Huang, Yu-Fang, Wang, Pei-Wei, Huang, Li-Wei, Yang, Winnie, Yu, Ching-Jung, Yang, Shang-Han, Chiu, Hsin-Hao, Chen, Mei-Lien
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; ABSORPTION; Adult; ALKYLATION; BIODEGRADATION; Biological and medical sciences; BLOOD; Breast; Breast milk; Chemical and industrial products toxicology. Toxic occupational diseases; COUPLING; Exposure; Female; Fetus - metabolism; FETUSES; FLUORESCENCE; Foetus; HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY; Humans; Infant; INFANTS; INTAKE; Intakes; LACTATION; MAMMARY GLANDS; Maternal-Fetal Exchange; Medical sciences; MILK; Mother; MOTHS; NEONATES; Nonylphenol; PHENOL; Phenols - pharmacokinetics; PLACENTA; Placenta - metabolism; Pregnancy; PRENATAL EXPOSURE; Probability theory; Risk; RISK ASSESSMENT; Risk Factors; TAIWAN; Toxicology; Various organic compounds
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2014.07.004

As the predominant environmental biodegradation product of nonylphenol (NP) ethoxylates and with proven estrogenic effects, NP is formed during the alkylation process of phenols. The purposes of this study were (1) to examine maternal and prenatal exposure to NP in Taiwan, (2) to determine the level of placental protection against NP exposure as well as the level of NP in breast milk, and (3) to assess the potential risk for breastfed newborns exposed to NP through the milk. Thirty pairs of maternal and fetal blood samples, placenta, and breast milk during the 1st and the 3rd months of lactation were collected. External NP exposures of these specimens were then analyzed by using high-performance liquid chromatography coupling with fluorescence detection. Next, the socio-demographics, lifestyle, delivery method, dietary and work history were collected using a questionnaire. In addition, the daily intake of NP from consuming breast milk in the 1st and 3rd months for newborns was studied through deterministic and probabilistic risk assessment methods. The geometric means and geometric standard deviation of NP levels in maternal blood, fetal cord blood, placenta, and breast milk in the 1st and 3rd months were 14.6 (1.7) ng/ml, 18.8 (1.8) ng/ml, 19.8 (1.9) ng/g, 23.5 (3.2) ng/ml, and 57.3 (1.4) ng/ml, respectively. The probabilistic percentiles (50th, 75th, and 95th) of daily intake NP in breast milk were 4.33, 7.79, and 18.39μg/kg-bw/day in the 1st month, respectively, and were 8.11, 10.78, 16.08μg/kg-bw/day in the 3rd month, respectively. The probabilistic distributions (5th, 25th, and 50th) of risk for infants aged 1 month old were 0.27, 0.64, and 1.15, respectively, and that for infants aged 3 month old were 0.31, 0.46, and 0.62, respectively. Through repeated exposure from the dietary intake of expectant mothers, fetuses could encounter a high NP exposure level due to transplacental absorption, partitioning between the maternal and fetal compartments. Daily NP intake via breast milk in three month-old babies exceeded the tolerable daily intake (TDI) of 5µg/kg bw/day indicated a potential risk for Taiwan infants. •A cohort of pregnant women was established and followed until delivery.•The pregnant and lactating mothers and their infants were exposed to NP.•Fetuses in Taiwan showed high NP milk level.•Daily NP intake via breast milk indicated a potential risk for Taiwan infants.