Dissipation and residues of picoxystrobin in peanut and field soil by QuEChERS and HPLC–MS/MS

Abstract

The dissipation and final residues of picoxystrobin in peanut and soil were determined by a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The dissipation and final residue of picoxystrobin at three different provinces (Hebei, Hubei, and Shandong) in China were studied. The fortification experiments at three different spiking levels of 0.01, 0.05, and 0.5 mg kg(-1) in all matrices (soil, peanut seedling, shell, stalk, and kernels) were conducted, and the recoveries were 79-114% with relative standard deviations of 3-12 (n = 5). The dissipation half-lives of picoxystrobin were 1.5-8.6 days in soil, and 2.1-2.8 days in seedlings. The final residues of picoxystrobin in supervised field trials were 0.05-6.82 mg kg(-1) in stalk, ≤0.381 mg kg(-1) in soil, ≤0.069 mg kg(-1) in shells, and ≤0.005 mg kg(-1) in peanut kernels. Considering the final residue levels and the maximum residue limits (MRLs), the pre-harvest interval of 14 days was recommended for the safe use of picoxystrobin in peanut crop.

Residue dissipation, transfer and safety evaluation of picoxystrobin during tea growing and brewing

“…The dissipation of picoxystrobin in soil at different sites has also been investigated and reported previously. For example, the t 1/2 of picoxystrobin were 10.3, 12.9 and 14.9 days in soil at Shandong, Tianjin and Jiangsu, respectively 14 ; the t 1/2 of picoxystrobin were 3.6, 1.5 and 8.6 days in soil at Hebei, Hubei and Shandong, respectively 18 ; the t 1/2 of picoxystrobin in photocatalytic degradation were 26.7, 32.8, 12.8 and 3.20 h on the surface of fluvo‐aquic soil, cinnamon soil, red soil and water, respectively, and the migration of picoxystrobin were 0.083, 0.08 and 0.25 in fluvo‐aquic soil, cinnamon soil and red soil, respectively 28 ; the t 1/2 of picoxystrobin ranged from 2.2 to 10.7 days in grapery soil 15 ; the t 1/2 of picoxystrobin was 11.6 days in open field soil and 23.1 days in plastic house soil 30 . And the t 1/2 of picoxystrobin were 4.18 and 17.32 days in soil at Shandong and Anhui, respectively 31 .…”

“…The dissipation of picoxystrobin has been investigated in other plants. For example, the t 1/2 of picoxystrobin were 2.70, 5.71 and 9.76 days for cucumber at Shandong, Tianjin and Jiangsu, respectively 14 ; the t 1/2 of picoxystrobin were 2.4, 2.8 and 2.1 days for peanut seedling at Hebei, Hubei and Shandong, respectively, and a pre‐harvest interval of 14 days was recommended for the safe use of picoxystrobin in peanut crop 18 ; the t 1/2 of picoxystrobin for grapefruit range from 5.9 to 12.6 days 15 ; the t 1/2 of picoxystrobin for whole watermelon were 1.43 and 3.71 days at Shandong and Anhui, respectively 31 . Thus, the different dissipation rates of picoxystrobin may be related to the growth dilution of tea and other plants, and differences in climate between different regions.…”

“…In recent years, residue analyses of picoxystrobin in different matrices have gradually increased. There have been many researches concerned with the environmental behaviors of picoxystrobin in different fruits and vegetables, such as watermelon, 13 cucumber, 14 grape, 15 pepper, 16 wheat 17 and peanut, 18 and also in water 19 and soil 14 ; analytical methods have been developed for picoxystrobin residue determination in various matrices, including vegetables, 16, 20–23 fruits, 13, 20, 21 baby foods, 24 soil, 13, 16, 25 irrigation water, 19 wheat 17 and Dendrobium officinale Kimura et Migo, 27 by gas chromatography with nitrogen–phosphorus and electron capture detection, 13, 14, 26, 27 high‐performance liquid chromatography (HPLC), 17, 22, 28 gas chromatography–mass spectrometry 19, 20, 24 and ultra‐performance liquid chromatography (UPLC)–mass spectrometry 15, 16, 18, 20, 21, 23, 25, 29–31 . Most of the limits of quantitation (LOQs) of these methods were from 0.005 to 0.05 mg kg −1 .…”

Dissipation, residues and risk assessment of pyraclostrobin and picoxystrobin in cucumber under field conditions

“…14,15,25 For example, Zhu et al reported the half-lives of picoxystrobin were 1.5-8.6 days in soil and 2.1-2.8 days in peanut seedlings. 14 The dissipation half-lives of picoxystrobin in oriental melon were 3.4-3.7 days reported by Kabir et al 15 You et al's results showed pyraclostrobin dissipated quickly in maize plant with half-lives of 1.6 to 1.7 days. 25 However, data from Guangdong showed no dissipation but an increase at 1 day after spraying.…”

“…13 Zhu et al determined the dissipation and final residues of picoxystrobin in peanut and soil via high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). 14 Kabir et al developed an analytical method for the determination of picoxystrobin in oriental melon using gas chromatography (GC)-electron capture detection (ECD) and mass spectrometry (MS). 15 Other than that, no available reports have put forward a method to detect pyraclostrobin and picoxystrobin simultaneously with LC-MS/MS in cucumber, and neither have there been any reports on the dissipation behavior of pyraclostrobin and picoxystrobin on cucumbers under field conditions, which is essential to evaluate their persistence in the environment.…”