Accuracy of the developed method and interference of matrix components were checked by performing analytical recovery experiments. Here a known amount of Benzene (i.e., 1.0, 2.0, 3.0 μL L−1) is added to the pre-analysed sample of the FGH. The concentration of Benzene is determined from regression line of the calibration curve. The results are presented in Table 2 which indicates the highest level of accuracy (100 ± 2%) compared to the required acceptance criteria (80–120%) for all the three concentrations selected for the study.