Determination of iron in hair samples by slotted quartz tube-flame atomic absorption spectrometry after switchable solvent liquid phase extraction.

•A sensitive and accurate method was developed using a green switchable solvent.•LOD and LOQ values were determined as 2.6 and 8.6 μg/L, respectively.•About 92-folds enhancement in detection power was obtained when compared to direct FAAS.•Recovery studies were carried out on human hair samples and satisfactory results were obtained.