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In this study, the attention was focused on quizalofop-ethyl, a chiral herbicide whose formulation has recently been marketed as quizalofop-P-ethyl, i.e. the (+)-enantiomer exhibiting herbicidal activity. To verify the real enantiomeric purity of this product as well as to study its environmental fate, the enantioselective separation of the P- and M- enantiomers of quizalofop-ethyl was achieved on Lux Cellulose-2 column (3‑chloro,4-methylphenilcarbamate cellulose) under isocratic conditions in polar organic mode. Once established that the commercial formulation contains ˜ 0.6% (enantiomeric fraction) of M as an impurity, an HPLC-MS/MS method was developed, validated and applied to the analysis of soil, carrots and turnips treated with the herbicide. A simple solid-liquid extraction allowed recoveries greater than 70%; limits of detections of P and M enantiomers were below 5 ng g⁻¹. The analyses of the real samples …