Acetamiprid in Rizhao green tea: Residue dynamics, degradation pathways, and ecological risks via integrated experimental and computational approaches

• 全文链接

日照绿茶中的啶虫脒：基于实验与计算联用技术的残留动态、降解路径及生态风险

关键词：

来源：

Journal of Hazardous Materials 期刊

全文链接：

//agri.nais.net.cn/topic/downloadFile/a72b81b7-c95e-468c-9700-436502614b2b

来源地址：

https://www.sciencedirect.com/science/article/pii/S0304389425017029

资源所属：

茶学研究专题

类型：

学术文献

语种：

英语

原文发布日期：

2025-09-05

摘要：

This study assesses the environmental persistence, processing effects, and toxicity mechanisms of acetamiprid in Rizhao green tea. Uniquely, we integrate season-resolved field trials, full-scale factory processing and atomistic DFT–docking analyses to deliver the first “field-to-cup” mass-balance for any neonicotinoid in tea. Field trials demonstrated concentration-dependent dissipation kinetics, with half-lives decreasing from 5.54 days (spring, RD) to 4.36 days (autumn, 3 ×RD). Seasonal variations, driven by higher autumn temperatures (18.2 °C vs. 12.5 °C) and light intensity (PAR: 1451 vs. 982 μmol/m²/s), significantly accelerated acetamiprid degradation. During tea processing, fixation reduced residues (PF<1), while drying caused significant accumulation (PF 2.63–2.99) due to high vapor pressure. GC-MS identified six degradation products, two of which—6-chloronicotinaldehyde and methyl 6-chloronicotinate—showed chronic toxicity to aquatic organisms (EC₅₀: 45.2–62.7 mg/L), though acute toxicity was absent. Density functional theory (DFT) revealed reactive sites in acetamiprid’s side chain, aligning with hydrolysis/oxidation pathways. Molecular docking and dynamics simulations elucidated acetamiprid’s neurotoxic mechanism: stable binding to nAChRs via hydrogen bonds with Trp-86 (−12.5 ± 0.8 kcal/mol contribution) and Lys-10, yielding a spontaneous binding energy of −5.5 kcal/mol. Seasonal harvesting adjustments (prolonged spring intervals) and optimized drying protocols are proposed to minimize residues. The study underscores the ecological risks of acetamiprid’s environmental persistence (soil half-life: 6.3–9.5 days) and transformation products, advocating for integrated agronomic practices to safeguard tea quality and aquatic ecosystems.