Development and application of a non-targeted extraction method for the analysis of migrating compounds from plastic baby bottles by GC-MS

In 2011, the European Union prohibited the production of polycarbonate (PC) baby bottles due to the toxic effects of the PC
monomer bisphenol-A. Therefore, baby bottles made of alternative materials, e.g. polypropylene (PP) or polyethersulphone
(PES), are currently marketed. The principal aim of the study was the identification of major compounds migrating from
baby bottles using a liquid–liquid extraction followed by GC/MS analysis. A 50% EtOH in water solution was selected as a
simulant for milk. After sterilisation of the bottle, three migration experiments were performed during 2 h at 70°C. A nontargeted
liquid–liquid extraction with ethyl acetate–n-hexane (1:1) was performed on the simulant samples. Identification of
migrants from 24 baby bottles was done using commercially available WILEY and NIST mass spectra libraries. Differences
in the migrating compounds and their intensities were observed between the different types of plastics, but also between the
same polymer from a different producer. Differences in the migration patterns were perceived as well between the
sterilisation and the migrations and within the different migrations. Silicone, Tritan™ and PP exhibited a wide variety of
migrating compounds, whereas PES and polyamide (PA) showed a lower amount of migrants, though sometimes in
relatively large concentrations (azacyclotridecan-2-one up to 250 µg kg−1
). Alkanes (especially in PP bottles), phthalates
(dibutylphthalate in one PP bottle (±40 µg kg−1
) and one silicone bottle (±25 µg kg−1
); diisobutylphthalate in one PP
(±10 µg kg−1
), silicone (up to ±80 µg kg−1
); and Tritan™ bottle (±30 µg kg−1
)), antioxidants (Irgafos 168, degradation
products of Irganox 1010 and Irganox 1076), etc. were detected for PP, silicone and Tritan™ bottles. Although the
concentrations were relatively low, some compounds not authorised by European Union Regulation No. 10/2011, such
as 2,4-di-tert-butylphenol (10–100 µg kg−1
) or 2-butoxyethyl acetate (about 300 µg kg−1
) were detected. Migrating
chemicals were identified as confirmed (using a standard) or as tentative (further confirmation required).