A green approach for the automatic quantitative analysis of additives in plastic samples using in-tube extraction dynamic headspace sampling technique coupled to GC-MS/MS

BACKGROUND

Many of the chemicals frequently used as additives have been recognised as hazardous substances, and therefore their analysis is necessary to evaluate plastic contamination risk. Additives analysis in plastic samples is usually performed by methods involving high volumes of toxic solvents or having high detection limits. In this work, a novel, fast, solventless and reliable green method was developed for the automated analysis of plastic additives from plastic samples. The proposed method consists of in-tube extraction dynamic headspace sampling (ITEX-DHS) combined with gas chromatography (GC) and mass spectrometry (MS/MS) determination.

RESULTS

Several parameters affecting the ITEX-DHS extraction of 47 additives in plastic samples (including phthalates, bisphenols, adipates, citrates, benzophenones, organophosphorus compounds, among others) were optimised. The use of matrix-matched calibration, together with labelled surrogate standards, minimises matrix effects, resulting in recoveries between 70 and 128%, with good quantitation limits (below 0.1 μg g-1 for most compounds) and precision (<20%). The method proposed can be applied to any type of polymer, but due to the existence of the matrix effect, calibrates with the adequate matrix should be performed for each polymer.

SIGNIFICANCE

This method represents an effective improvement compared to previous methods because it is fast, solvent-free, fully automated, and provides reliable quantification of additives in plastic samples.