Method Development for Effect-Directed Analysis of Endocrine Disrupting Compounds in Human Amniotic Fluid

Area of Science:

• Environmental Chemistry
• Toxicology
• Reproductive Biology

Background:

• The developing fetus is highly susceptible to endocrine disrupting compounds (EDCs).
• Assessing EDC risks is challenging due to limited data on direct in utero exposure.
• Amniotic fluid (AF) offers a direct window into the fetal chemical environment.

Purpose of the Study:

• To develop and validate a robust analytical method for identifying known and unknown EDCs in human amniotic fluid.
• To quantify the biological activity (estrogenic, androgenic, dioxin-like) of AF extracts.
• To identify specific chemicals contributing to the observed bioactivity.

Main Methods:

• Developed and validated a combined solid phase extraction and dispersive liquid/liquid extraction method for AF.
• Utilized cell-based reporter gene assays to measure estrogenic, androgenic, and dioxin-like activities.
• Employed targeted analysis and reversed-phase chromatographic fractionation for chemical identification and activity correlation.

Main Results:

• The analytical method achieved maximal recoveries and minimal matrix interference for a wide range of EDCs.
• AF extracts exhibited significant estrogenic (1.4 nmol EEQ/L), androgenic (76.6 pmol DHT-EQ/L), and dioxin-like (10.1 pmol TEQ/L) activities.
• Thirteen known compounds (xenobiotics, phytoestrogens, hormones) were identified, partially explaining the bioactivity.
• Activity was detected across various fractions, indicating the presence of diverse, unidentified bioactive substances.

Conclusions:

• A novel, validated method enables comprehensive EDC analysis in amniotic fluid.
• The study confirms the presence of biologically active EDCs in the human fetal environment.
• This work is a crucial first step towards identifying unknown compounds affecting fetal development through effect-directed analysis.