1.Plasma metabolomics study in patients with occupational silicosis
HANYing QINYi ru JINJia chun SUNYang le WUBang hua XIALi hua ZHAONa HUANGYong shun
China Occupational Medicine 2022;51(03):280-
Abstract: Objective
To analyze the plasma metabolomics of patients with occupational silicosis, and screen the differential
Methods
metabolic pathways in different stages of silicosis. Thirty patients with occupational silicosis were selected as
silicosis group by judgment sampling method, including 10 patients in each subgroups with silicosis at stages Ⅰ, Ⅱ, and Ⅲ.
Another 10 healthy individuals without occupational dust exposure history were selected as the control group. Plasma of each
patientwascollected.Themetabolitesfromtheirplasmasampleswerecollectedandidentifiedbyuntargetedmetabolomicsusing----ultraperformanceliquidchromatographyquadrupoletimeofflightmassspectrometry.Principalcomponentanalysisandpartial
least square discriminant analysis were used to compare the differentially expressed metabolites. The metabolic pathways
Results
enrichment analysis was performed using MetaboAnanlyst 5.0 and other metabolic analysis software. There were
significantlydifferentmetabolicprofilesamongtheplasmaofthesilicosissubgroupsandthecontrolgroup.Inthepositivemode,--149differentmetaboliteswerescreened,amongwhich99metaboliteswereupregulatedand50metabolitesweredown
regulated. Sphingolipids metabolism, arginine and ornithine metabolism, and fatty acid degradation are the main metabolic
pathwaysinsilicosissubgroupswithstagesⅠandⅡcomparedwiththecontrolgroup.Themetabolicpathwaysofsilicosisstage
Ⅲ are arginine and proline metabolism, glycerol metabolism, glyoxylic acid and dicarboxylic acid metabolism, and glycine,
Conclusion
serine and threonine metabolism. The plasma metabolic profile of patients with silicosis in different stages
changed significantly. Sphingolipid metabolism is the main metabolic pathway in the early and middle stages of silicosis. In
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silicosisterminalstage,thechangeofarginineandproline basedmetabolicpathwayresultinginfibrosisaggravation.
2.A comprehensive method for determination of 55 traditional and emerging per- and polyfluoroalkyl substances in infant complementary foods using liquid chromatography-high resolution mass spectrometry
Ziwei LIANG ; Chao FENG ; Jiawen YOU ; Zixin QIAN ; Sunyang LE ; Dasheng LU
Journal of Environmental and Occupational Medicine 2025;42(2):211-217
Background Per- and polyfluoroalkyl substances (PFASs) are a class of persistent organic pollutants that pose potential health risks to humans. Infants and young children have higher requirements for food safety due to the underdeveloped detoxification and immune systems. Therefore, developing a comprehensive method for determination of PFASs and their novel alternatives in infant complementary food is of great significance. Objective To develop an analytical method using liquid chromatography high-resolution mass spectrometry technology for determination of 55 PFASs in plant- and animal-derived infant complementary fruit purees. Methods Oasis WAX (200 mg, 6 CC) solid-phase extraction columns were used for sample enrichment and purification. The pH of the acetonitrile extract was adjusted using 0%, 1%, 1.5%, and 2% formic acid aqueous solutions to evaluate its impact on the recovery rate of target compounds. Additionally, the impact of a 2 mL methanol wash during the purification process on the recovery of target compounds was assessed to determine the optimal pretreatment conditions. Three types of chromatographic columns—Agilent Poroshell 120 EC-C18, Thermo InfinityLab Poroshell 120 Aq-C18, Acquity Waters BEH-C18, and changes in mobile phase, were compared for their effects on retention time, peak shape, and response of target compounds. The method was validated in terms of selectivity, linear range, detection limit, and precision. The established method was applied to 49 commercial samples of infant complementary fruit purees. Results Adjusting the sample pH using 1.5% formic acid water and incorporating a 2 mL methanol wash during purification achieved satisfactory recovery rates. The target compounds were chromatographically separated using an Agilent Poroshell 120 EC-C18 column with a gradient elution system. The mobile phase consisted of methanol-water (methanol/water: 2/98, v/v) containing 5 mmol·L−1 ammonium formate as mobile phase A, and methanol as mobile phase B. Good separation was achieved within 15 min, resulting in optimal chromatographic peak shapes. The 55 target compounds exhibited good linearity across the standard curve range, with correlation coefficients (R²) greater than 0.99. The method detection limits ranged from 0.02 to 0.05 µg·L−1. In the plant- and animal-based fruit puree samples, the spiked recovery rates ranged from 60% to 112% and 57% to 119%, respectively, with relative standard deviations (RSD) ≤ 30%. A total of 9 traditional PFASs and 5 novel PFASs were positive in 49 samples of infant complementary fruit purees. Conclusion This method enables comprehensive detection of 55 traditional and emerging PFASs, offering wide coverage, high accuracy, and excellent sensitivity. It provides technical support for characterizing contamination by traditional and emerging PFASs in food matrices.
3.Determination of eight high polar pesticide residues in vegetables and fruits by hydrophilic interaction liquid chromatography combined with ultra-performance liquid chromatography-tandem mass spectrometry
Yu’e JIN ; Qian XU ; Liming XUE ; Sunyang LE ; Libei XIONG ; Yan TANG ; Jingyi WAN ; Guoquan WANG
Journal of Environmental and Occupational Medicine 2022;39(6):701-707
Background The production and consumption of high polar pesticides in China are the largest in the world. Therefore, it is urgent to develop a method with fast analysis, large flux, and high accuracy to determine the residues of these pesticides in food. Objective To establish a method for the determination of eight highly polar pesticides [chlormequat, paraquat, difenzoquat, cyromazine, propamocarb, glyphosate, (aminomethyl)-phosphonic acid, and glufosinate] in vegetables and fruits by ultra-performance liquid chromatography-tandem mass spectrometry. Methods After comparing various types of hydrophilic interaction liquid chromatography (HILIC) columns, and optimizing pH value and buffer concentration of mobile phase, effective chromatographic retention and separation of selected eight pesticides were achieved. Based on the optimization of mass spectrometry under chromatographic conditions, a multiple reaction monitoring (MRM) channel of target compounds was established. In the sample pretreatment, through optimization of water content, extraction solvent, and purification method, a final MRM mode of ultra-performance liquid chromatography-tandem mass spectrometry was used for detection, and the isotope internal standard method was used for quantification. The accuracy and the precision of the method were evaluated using recovery and relative standard deviation. The established method was applied to detect 57 samples of retail vegetables and fruits to investigate the adaptability of the proposed method and the residual levels of selected high polar pesticides. Results For positive ion electrospray ionization (ESI+) detection, we chose Sielc Obelisc R as chromatographic column, and 20 mmol·L−1 ammonium formate solution (pH=3±0.05) and acetonitrile as mobile phase; for negative ion electrospray ionization (ESI−) detection, we chose Shodex Asahipak NH2P-50 2D as chromatographic column, and 5 mmol·L−1 ammonium acetate solution (pH=11±0.05) and acetonitrile as mobile phase to obtain good chromatographic separation and peak shape. Under the optimal conditions of sample water content standardization, using 2% acidified methanol as extraction solvent, and C18 dispersed solid phase extraction purification, the linearity ranges of five analytes (chlormequat, paraquat, difenzoquat, cyromazine, and propamocarb) and three analytes [glyphosate, (aminomethyl)phosphonic acid, and glufosinate] were 1.00-100 μg·L−1 and 5.00-500 μg·L−1 (both correlation coefficients>0.999) respectively, the detection limits were 0.002-0.010 mg·kg−1, and the limits of quantification (LOQ) were 0.005-0.025 mg·kg−1. At three spiked levels (LOQ, 2LOQ, and 5LOQ), the recoveries were in the range of 85.3%–113.2%, and the relative standard deviations were 1.5%–9.5% (n=6). Three target pesticides (chlormequat, cyromazine, and propamocarb) were detected in 57 samples of retail vegetables and fruits, and the residue of chlormequat in cowpea exceeded the maximum residue limit. Conclusion The established method of HILIC combined with ultra-performance liquid chromatography-tandem mass spectrometry and isotopic internal standard quantification has the characteristics of simplicity, stability, and easy operation, which is suitable for rapid screening and quantitative detection of selected eight high polar pesticide residues in large quantities of vegetables and fruits, and provides technical support for monitoring and risk assessment of high polar pesticide residues.