Migration test of Bisphenol A from polycarbonate cups using excitation-emission fluorescence data with parallel factor analysis.

Bisphenol A (BPA) is one of the most largely produced chemical in the world; it is used to make plastics and epoxy resins. The endocrine disruptor potential of BPA is well known, but recent researches suggest a relationship between chronic exposure to BPA, genotoxic activity and epigenetic modifications. The main source of exposure to BPA includes food contact materials (FCM). Thus simple and robust test methods are needed to improve the migration test of BPA. In this work, a non-separative, easy, fast and inexpensive spectrofluorimetric method based on the second order calibration of excitation-emission fluorescence matrices (EEMs) was proposed for the determination of BPA. For the first time, molecular fluorescence was used to identify unequivocally and quantify BPA. Trilinearity of the data tensor guarantees the uniqueness of the solution obtained through parallel factor analysis (PARAFAC), so one factor of the decomposition matches up with BPA even if other fluorophores are in the test sample. The effect of four experimental factors of the procedure on the figures of merit and the unequivocally identification was investigated by means of a D-optimal design and PARAFAC calibration. The method is linear and accurate in the range 0-720µgL-1. The decision limit CCα and detection capability CCβ are 6.63µgL-1 and 18.85µgL-1 respectively (with probabilities of false positive and false negative fixed at 0.05). Finally the proposed method was applied to carry out a migration test from two polycarbonate cups, using 3% (w/v) acetic acid in aqueous solution as food simulant. The migrated amount of BPA was found to be 688.7µgL-1 (n=5) for the first cup and 710.5µgL-1 (n=4) for the second one, above the specific migration limit set by EFSA (European Food Safety Authority).