**5. Conclusions**

A comparative study was conducted to determine the effectiveness of removing ten pesticide residues from five leafy vegetables artificially contaminated with pesticides using nine removal methods. The reduction range for each method was 43.7–77.0% and that for five leafy vegetables was 40.6–67.4%. Lettuce had the highest reduction (67.4 ± 7.3%), whereas ssamchoo had the lowest reduction (40.6 ± 12.9%). Spinach and crown daisy showed no significant difference in their reductions. On average, removal using running water (77.0 ± 18.0%) and boiling (59.5 ± 31.2%) led to the highest reduction, whereas using detergent (43.7 ± 14.5%) led to the lowest reduction. The reductions in chlorfenapyr, diniconazole, indoxacarb, fludioxonil, pyraclostrobin, and lufenuron in the five leafy vegetables were lower following blanching and boiling than that following the other methods. High log *P* values (3.99–5.12, which is greater than 1) were considered to be one of the causes of this result. Therefore, to increase the removal efficiency of these pesticide residues, the vegetable must be boiled and blanched after sufficient washing. Further research on various leafy vegetables associated with high consumption of pesticides should be conducted based on our results, as leafy vegetables have a high risk of pesticide residue contamination.

**Supplementary Materials:** The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/foods11182916/s1, Table S1: The results of nine washing methods for pesticide reduction in five leafy vegetables (*n* = 5). Figure S1: The effect of the treatment on the appearance of the vegetables (spinach and ssamchoo). Note: A: Unwashed, B: Alkaline water washing, C: Blanching, D: Boiling, E: NaHCO3, F: Detergent, G: Running water, H: Stagnant water, I: Ultrasonic cleaning, and J: Vinegar.

**Author Contributions:** S.-J.Y.: Methodology, analysis, interpretation of data, writing the original draft, statistical analysis, and visualization. S.M.: Methodology, validation, analysis, and interpretation of the data, statistical analysis, and visualization. H.J.K.: Methodology, validation, investigation, analysis, and interpretation of the data. S.J.H.: Methodology, investigation, analysis, and interpretation of the data. D.W.K.: Methodology, investigation, analysis, and interpretation of the data. B.-S.C.: Supervision, writing—review, and editing. A.G.K.: Methodology, supervision, visualization, analysis, and interpretation of data. D.W.P.: Conception and design of the study, methodology, writing—original draft, analysis and interpretation of data, visualization. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data is contained within the article or supplementary materials and is available upon reasonable request from the corresponding author.

**Acknowledgments:** This study was supported by a research project of the Health and Environment Research Institute of Gwangju, Korea.

**Conflicts of Interest:** The authors declare no conflict of interest.
