Endosulfan is an endocrine disruptor that negatively affects the human central nervous system. Although perennial root vegetable crops have high risks of endosulfan absorption and transfer in soil, safety management studies addressing this problem are lacking. We evaluated endosulfan absorption and transition, as well as plant growth in ginseng cultivation soil, and developed a safety management method for field application. Total endosulfan residual concentrations in the soil and biochar 0.1–1.0% treatment groups were 52–73% after 532 d of spraying, and there was no reduction effect owing to biochar treatment. However, the endosulfan sulfate conversion rate decreased by 21.6–47.1% as the biochar amount increased. Further, there was a 47–95% reduction in the absorption and migration of endosulfan into ginseng in the biochar treatment compared to the control, demonstrating a reduction effect (p < 0.05). Ginseng grown in soil treated with 0.1% biochar showed no growth parameter differences compared to the control (p > 0.05); however, germination rates decreased to <59% when the soil was treated with ≥0.3% biochar. Soil treatment with 0.1% biochar can reduce endosulfan absorption and migration without adversely affecting crop growth. This treatment can be used at the cultivation site, depending on soil conditions.

Establishing pesticide safety management for agricultural products necessitates accurate pesticide analysis at analytical laboratories. Proficiency testing is regarded an effective method for quality control. Herein, proficiency tests were carried out for residual pesticide analysis in laboratories. All samples satisfied the homogeneity and stability criteria of the ISO 13528 standard. The obtained results were analyzed using the ISO 17043 z-score evaluation. Both individual pesticide and multiresidue proficiency evaluations were performed, and the proportion of z-scores within the ±2 range (“Satisfactory” rating) obtained for seven pesticides ranged 79–97%. Of the laboratories, 83% were classified as Category A using the category A/B method, and these also received AAA ratings in the triple-A evaluations. Furthermore, 66–74% of the laboratories were rated “Good” via five evaluation methods based on their z-scores. The sum of weighted z-scores and scaled sum of squared z-scores were considered as the most suitable evaluation techniques, as they compensated for the drawbacks of good results and corrected the poor results. To identify the main factors affecting laboratory analysis, the experience of the analyst, sample weight, calibration curve preparation method, and cleanup status were considered. A dispersive solid phase extraction cleanup significantly improved the results (p < 0.01).