Temperature controlled ionic liquid-dispersive liquid phase microextraction for determination of trace lead level in blood samples prior to analysis by flame atomic absorption spectrometry with multivariate optimization

► Trace Pb2+ analysis in blood samples of healthy children and with different respiratory disorders. ► Preconcentration of Pb2+ in acid digested blood samples after chelating with a complexing reagent. ► Using multivariate technique for screening the significant factors influencing TIL-DLME of Pb2+. ► The level of Pb2+ in diseased children was significantly higher than referents of same age group.