Detection and quantification of microplastics in meconium by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS)

• Py-GC/MS was first applied to analyze microplastics in meconium. • 8 kinds of microplastics were quantified with high sensitivity and good linearity. • PE was the major microplastic in meconium, followed by PVC. • 8 targeted microplastics were widely detected, ranging from 51.67%-70.67%. Microplastics are widely present in the environment and have been found in human biological samples. However, their adverse effects on human remain unclear due to methodological limitations in microplastic analysis. This study aims to develop and validate a Py-GC/MS based analytical method for quantifying 8 typical microplastics in meconium samples. Meconium samples were pretreated via acid digestion, filtration, and analyzed by Py-GC/MS. All 8 microplastics exhibited linear coefficients (R 2 ) exceeding 0.99. Recovery rates (excluding polyethylene terephthalate) ranged from 65.24% to 114.27%, with precision values (RSD) of 2.16% to 14.85%. Application of this method to 60 meconium samples revealed the presence of all 8 target microplastics, with the concentrations ranging from 1.60 × 10 -5 to 1.53 × 10 3 μg/g and detection rates ranging from 51.67% to 70.67%. This method provides a robust technical approach for detecting microplastics in meconium and evaluating associated health risks.