Chemometrics-Assisted QuEChERS Method Coupled with HPLC-Diode Array Detection for the Determination of Phthalate Esters in Food-Grade Plastics

Abstract

An effective method for the determination of four phthalate esters in plastic products for food usage was developed using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) approach coupled with HPLC-diode array detection. Both the extraction and clean-up steps of the procedure were optimized using chemometrics methods. Under the optimized conditions, calibration model was linear from 10.0 to 500 μg/kg for benzyl butyl phthalate and from 5.0 to 500 µg/kg for dimethyl phthalate, dibutyl phthalate and diethylhexyl phthalate (R² ≥ 0.9859). The limits of detection and of quantification were less than 3 and 7 μg/kg, respectively. The repeatability and intermediate precision of the proposed method (relative standard deviations) were ≤6.4 and ≤9.2%, respectively. The proposed method is easy, precise, and accurate, and applicable for the determination of phthalic acid esters in plastics for food use classified as polyethylene terephthalate and polystyrene.