Objective To evaluate the residue dissipation dynamics and dietary intake risks of sodium dichloroisocyanurate (DCCNa), prochloraz and its metabolites in Myrica rubra Sieb. & Zucc. Methods The residue dynamics of DCCNa, prochloraz and its metabolite 2,4,6-trichlorophenol in Myrica rubra Sieb. & Zucc under room temperature and cold storage conditions were quantitatively analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), dietary intake risks were further assessed. Results There was a positive correlation between the concentration and residual amount of DCCNa and prochloraz in fruit soaking, indicating that higher dipping concentrations resulted in greater initial residues. The dissipation dynamics of both pesticides in Myrica rubra Sieb. & Zucc followed the first-order kinetics. The half-lives of DCCNa were 0.5-0.9 days at room temperature and 0.8-1.1 days under refrigeration, while those of prochloraz were 1.1-1.3 days and 1.5-2.1 days respectively. Additionally, the content of 2,4,6-trichlorophenol, a metabolite of prochloraz, exhibited an increasing trend during storage. Dietary risk assessment demonstrated that when Myrica rubra Sieb. & Zucc were treated with DCCNa (15 mg/L and 60 mg/L) or prochloraz (45 mg/L and 180 mg/L) solutions for preservation respectively, the acute dietary exposure risks of both pesticides in at the highest residue levels remained within the acceptable limits. Moreover, acute dietary risk values of DCCNa and prochloraz in commercially available Myrica rubra Sieb. & Zucc were lower than those in the experimental treatment groups, with all acute dietary exposure risks below 100%, indicating controllable exposure levels. Conclusion This study clarifies the degradation patterns of sodium DCCNa, prochloraz and their metabolites during the storage and preservation process of Myrica rubra Sieb. & Zucc, providing a theoretical basis for the scientific and standardized use of fungicidal preservatives as well as quality and safety regulation.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |