Detection of 20 phthalate esters in breast milk by GC-MS/MS using QuEChERS extraction method

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Food Safety

Background:

• Phthalate esters (PAEs) are common endocrine disruptors found in various consumer products.
• Breast milk can be a route of exposure to PAEs for infants.
• Accurate detection methods are crucial for assessing human exposure and health risks.

Purpose of the Study:

• To establish a sensitive and reliable method for detecting 20 different PAEs in human breast milk.
• To quantify the levels of specific PAEs in a cohort of breast milk samples.
• To provide a tool for routine monitoring of PAE contamination in breast milk and dairy products.

Main Methods:

• Development of a quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and clean-up procedure.
• Utilized acetonitrile as the extraction solvent and PSA/C18 as clean-up materials to remove lipids and fatty acids.
• Quantitative analysis performed using gas chromatography-mass spectrometry/mass spectrometry (GC-MS/MS) with five internal standards.

Main Results:

• The method demonstrated a linear range of 5.0-500.0 µg/L with high recoveries (83.3-123.3%) and low relative standard deviations (0.2-7.6%).
• Method detection limits (LODs) for the 20 PAEs ranged from 0.004-1.3 µg/kg.
• Five PAEs, including dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), di-n-butyl phthalate (DBP), and bis(2-ethylhexyl) phthalate (DEHP), were detected in 35 breast milk samples, with concentrations ranging from 0.5 to 137.3 μg/kg.

Conclusions:

• The established QuEChERS-GC-MS/MS method is fast, simple, sensitive, and accurate for detecting 20 PAEs in breast milk.
• The presence of multiple PAEs in breast milk highlights potential exposure pathways for infants.
• This method is suitable for the analysis of PAEs in breast milk and potentially other dairy products, aiding in food safety assessments.