Degradation properties and identification of metabolites of 6-Cl-PMNI in soil and water. (March 2016)

• Record Type: Journal Article
• Authors: Wang, Yihu; Sun, Qianqian; Tian, Chunxia; Gui, Wenjun; Zhu, Guonian
• Is Part Of: Chemosphere. Volume 147(2016)
• Page Start: 287
• Page End: 296
• Publication Date: 2016-03
• Subjects: 6-Cl-PMNI -- Degradation half life -- Water -- Soil -- Metabolite; 6-Cl-PMNI 2-chloro-5-[[2- (nitromethy-l-ene)-1-imidazolidinyl] methyl] pyridine -- CYC cycloxaprid -- HPLC high performance liquid chromatography -- UPLC-MS/MS ultra performance liquid chromatography tandem mass spectrometry -- LLE liquid–liquid extraction -- MLOD limit of detection for standard -- MLOQ limit of quantification for standard -- rpm rotation per min -- RT retention time -- OM organic matter; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2015.12.020
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: In order to provide the scientific basis for the environmental risk assessment of cycloxaprid and 6-Cl-PMNI (intermediate of cycloxaprid), the degradation properties of 6-Cl-PMNI in aerobic, anaerobic and/or sterile soil, as well as in water with different pH values at different temperature were explored under laboratory conditions using HPLC for its kinetics study and UPLC-MS/MS for the identification of its metabolites/degradation products. Fortification study showed that the recoveries of 71.4–100.5% with the maximum coefficient variation (CV) of 7.47% were obtained. The linear range was 0.1–10 mg/L with the good linearity of R 2 = 0.9990. For standard, the method LOD (limit of detection) and LOQ (limit of quantification) was 0.03 mg/L and 0.1 mg/L, respectively. Results demonstrated the good performance of the developed method. Kinetics study indicated that the degradation half-lives (t0.5 ) in pH 3-pH 10 buffers varied from 111.8 d to 288.8 d at 25 °C but rapidly shortened to 1.6–25.7 d at 70 °C. Good negative linear ships (R 2 ≥ 0.8423) between half life and temperature were found. 6-Cl-PMNI could be readily degraded in non-sterile soil (t0.5 0.8–7.5 d) while slowly degraded in sterile soil (t0.5 64.8–91.2 d). Three hydrolytic products and one metabolite of 6-Cl-PMNI in aerobic soil were identified. The CC olefinic bond reacted with H2 O by Markovnikov Additive Reaction and the split of C–Cl were mainly proposed as the possible reaction pathway for 6-Cl-PMNI degradation in water and in soil, respectively. Graphical abstract: Highlights: 6-Cl-PMNI is stable in room temperature and neutral media. Temperature is the main fact which influences the hydrolysis of 6-Cl-PMNI. The CC olefinic bond reacted with H2 O may be the main hydrolytic mechanism. 6-Cl-PMNI can be readily degraded in soil mainly by microbial action. The split of C–Cl is proposed as the degradation pathway of 6-Cl-PMNI in soil.