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Recently, traces of brominated flame retardants (BFRs) have been detected in black plastic food-contact materials (FCMs), indicating the presence of recycled plastics, mainly coming from waste electric and electronic equipment (WEEE) as BFRs are one of the main additives in electric applications. In order to evaluate efficiently and preliminary in situ the presence of WEEE in plastic FCMs, a generic procedure for the evaluation of WEEE presence in plastic FCMs by using defined parameters having each an associated importance level has been proposed. This can be achieved by combining parameters like overall bromine (Br) and antimony (Sb) content; additive and reactive BFR, rare earth element (REE) and WEEE-relevant elemental content and additionally polymer purity. In most of the cases, the WEEE contamination could be confirmed by combining X-ray fluorescence (XRF) spectrometry and thermal desorption/pyrolysis gas chromatography-mass spectrometry (GC-MS) at first. The Sb and REE content did not give a full confirmation as to the source of contamination, however for Sb the opposite counts: Sb was joined with elevated Br signals. Therefore, Br at first followed by Sb were used as WEEE precursors as both elements are used as synergetic flame-retardant systems. WEEE-specific REEs could be used for small WEEE (sWEEE) confirmation; however, this parameter should be interpreted with care. The polymer purity by Fourier-transform infrared spectrometer (FTIR) and pyrolysis GC-MS in many cases could not confirm WEEE-specific contamination; however, it can be used for purity measurements and for the suspicion of the usage of recycled fractions (WEEE and non-WEEE) as a third-line confirmation. To the best of our knowledge, the addition of WEEE waste to plastic FCMs is illegal; however, due to lack on screening mechanisms, there is still the breakthrough of such articles onto the market, and, therefore, our generic procedure enables the quick and effective screening of suspicious samples.

In order to confirm the possibility that recycled fractions from the waste electrical and electronic equipment (WEEE) stream were illegally entering the European market in black polymeric food-contact articles (FCAs), bromine quantification, brominated flame retardant (BFR) identification combined with WEEE-relevant elemental analysis and polymer impurity analysis were performed. From the 10 selected FCAs, seven samples contained a bromine level ranging from 57 to 5975 mg kg(-)(1), which is lower than expected to achieve flame retardancy. The BFRs that were present were tetrabromobisphenol A (TBBPA), decabromodiphenylether (decaBDE), decabromodiphenylethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE). Typical elements used in electronic equipment and present in WEEE were detected either at trace level or at elevated concentrations. In all cases when bromine was detected at higher concentrations, concurrently antimony was also detected, which confirms the synergetic use of antimony in combination with BFRs. This study describes also the measurement of rare earth elements where combinations of cerium, dysprosium, lanthanum, neodymium, praseodymium and yttrium were detected in four of the seven BFR-positive samples. Additionally, polymer purity was investigated where in all cases foreign polymer fractions were detected. Despite the fact that this study was carried out on a very small amount of samples, there is a significant likelihood that WEEE has been used for the production of FCAs.