Analysis of phthalates in milk and milk products by liquid chromatography coupled to quadrupole Orbitrap high-resolution mass spectrometry.

A new analytical method was developed and validated for simultaneous analysis of 27 phthalates in milk and milk products. Response surface methodology was employed to optimize a quick, easy, cheap, effective, rugged, and safe (QuEChERS) sample preparation method. Ultrahigh-performance liquid chromatography and electrospray ionization quadrupole Orbitrap high-resolution mass spectrometry (UHPLC/ESI Q-Orbitrap) was used for the separation and detection of all the analytes. The method was validated by taking into consideration the guidelines specified in Commission Decision 2002/657/EC and 2007/19/EC. The extraction recoveries were in a range of 90.7% to 104.6%, with coefficient of variation <5.6%. The 27 compounds behave dynamic range in the 0.1-1000μgkg(-1) concentration, with correlation coefficient >0.99. The limits of detection for the analytes are in the range 0.32-2.6μgkg(-1). This method has been successfully applied on screening of phthalates in 96 commercial milk and milk product samples.