GC-MS assisted with chemometric methods applied for investigation of migration behavior of phthalate plasticizers in fatty foods simulant

PVC films with different thickness and different contents of 9 phthalate plasticizers (PAEs) were manufactured according to a uniform design method. The migration contents of PAEs in isooctane, which was set as a fatty foods simulant, were first determined using GC-MS analysis. It was found that the chromatographic peaks of diisononyl ortho-phthalate (DINP) and diisodecyl ortho-phthalate (DIDP) very considerably overlapped, with a lower signal to noise ratio (SNR). For resolution of the noisy overlapped peaks, twice continuous wavelet transform (CWT) was adopted. Then, the migration models of PAEs were obtained by the non-negative least squares method (NNLS). The results show that the noisy overlapped peaks were successfully resolved with increasing the SNR 10 times; the migration ratio of the 9 PAEs at 70 C are located with the range 0.0556-0.3383 %; the migration amount of a specific plasticizer is proportional to its content and some coexisting plasticizers; temperature is a significant impact factor for the migration process. The proposed chemometric-assisted GC-MS analysis provides a new approach for investigation of this complex process. © 2013 Springer-Verlag Berlin Heidelberg.