Selective extraction and determination of Cr(VI) in food samples based on tandem electromembrane extraction followed by electrothermal atomic absorption spectrometry

•Combination of EME with µ-EME for selective extraction of Cr(VI) was first reported.•The proposed method was used for the quantification of Cr(VI) in complex food samples.•The EME-µ-EME provided very high enrichment factor (>500) for Cr(VI).•The proposed method showed high extraction efficiency and excellent sample clean up.