Validated method for the determination of perfluorinated compounds in placental tissue samples based on a simple extraction procedure followed by ultra-high performance liquid chromatography tandem mass spectrometry analysis

Xenobiotic exposure during pregnancy is inevitable. Determination of perfluorinated compounds (PFCs), chemicals described as environmental contaminants by Public Health Authorities due to their persistence, bioaccumulation and toxicity, is a challenge. In the present work, a method based on a simplified sample treatment involving freeze–drying, solvent extraction and dispersive clean-up of the extracts using C₁₈ sorbents followed by an ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) analysis was developed and validated for the determination of five perfluorinated carboxylic acids (C₄–C₈) and perfluorooctane sulfonate (PFOS) in placental tissue samples. The most influential parameters affecting the extraction method and clean-up were optimized using Design of Experiments (DOE). The method was validated using matrix-matched calibration. Found limits of detection (LODs) ranged from 0.03 to 2 ng g⁻¹ and limits of quantification (LOQs) from 0.08 to 6 ng g⁻¹, while inter- and intra-day variability was under 14% in all cases. Recovery rates for spiked samples ranged from 94% to 113%. The method was satisfactorily applied for the determination of compounds in human placental tissue samples collected at delivery from 25 randomly selected women.