Objective To establish a method for simultaneous determination of four high-molecular-weight thiol derivatives (TDs) in workplace air by gas chromatography. Methods The four kinds of vapor-phase macromolecular TDs (1-pentanethiol, 1-hexanethiol, 1-benzyl mercaptan, and n-octanethiol) in the workplace air were collected using the GDH-1 air sampling tubes, desorbed with anhydrous ethanol, separated on a DB-FFAP capillary column, and determined by flame ionization detector. Results The quantitation range of the four TDs was 0.30-207.37 mg/L, with the correlation coefficients greater than 0.999 00. The minimum detection mass concentrations and minimum quantitation mass concentrations were 0.18-0.32 and 0.60-1.05 mg/m³, respectively (both calculated based on the 1.5 L sample and 3.0 mL desorption solvent). The mean desorption efficiencies ranged from 87.07% to 103.59%. The within-run and between-run relative standard deviations were 1.92%-8.22% and 1.89%-8.45%, respectively. The samples can be stored at room temperature or 4 ℃ for three days and up to 7 days at -18 ℃. Conclusion This method is suitable for the simultaneous determination of four vapor-phase TDs in workplace air.

Objective To explore the nephrotoxic effects of exposure to perfluorobutanoic acid (PFBA) and its mechanism in mice, with a particular focus on analyzing the changes in kidney metabolism and their potential implications. Methods The specific pathogen free C57BL/6 mice were randomly divided into control group, low-dose group, and high-dose group, with 10 mice in each group. Mice in the three groups received intragastric administration of PFBA solution at doses of 0, 35 and 350 mg/kg body weight, once per day for seven consecutive days. The histopathological changes of kidneys of mice in these three groups were evaluated. Metabolomic profiling of mouse kidneys was performed using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Differentially accumulated metabolites (DAMs) were identified based on the Human Metabolome Database, and related metabolic pathways were analyzed through MetaboAnalyst 6.0 and Kyoto Encyclopedia of Genes and Genomes (KEGG). Results Histopathological analysis of kidneys showed that the renal pelvis mucosa of mice in the low-dose group presented focal mild inflammatory changes without marked structural damage, whereas mice in the high-dose group showed severe inflammation and partial destruction of renal structure. The kidney coefficient of mice in both low-dose group and the high-dose group decreased (both P<0.05), and the Paller scores of renal tissues increased (both P<0.05) compared with that in the control group. The Paller score of mouse renal tissue in the high-dose group was higher than that in the low-dose group (P<0.05). Metabolomic profiling identified 46 DAMs (26 upregulated, 20 downregulated) in the low-dose group and 104 DAMs (54 upregulated, 50 downregulated) in the high-dose group, with 26 shared DAMs between the two dose groups. KEGG pathway analysis revealed that DAMs were mainly involved in metabolic pathways such as glycerophospholipid metabolism, glycerolipid metabolism, sphingolipid and steroid hormone synthesis. Conclusion Acute exposure to PFBA can cause kidney injury in mice. Lipid metabolism pathways such as glycerophospholipid and sphingolipid metabolism is involved in the development of acute renal toxicity of PFBA.

Objective To establish an ultra-high-performance liquid chromatography-triple quadrupole tandem mass spectrometry method for the determination of N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine quinone (6PPDQ) in human plasma and urine. Methods Plasma and urine samples (0.3 mL each) were mixed with 0.9 mL acetonitrile and dichloromethane, vortexed, and subjected to ultrasonic treatment to facilitate extraction. After centrifugation, the extract was collected, evaporated to dry powder under nitrogen, and reconstituted. Separation was performed on a C18 column, and detection was carried out using ultra-high-performance liquid chromatography-triple quadrupole tandem mass spectrometry with external standard quantification. Results 6PPDQ showed good linearity in the range of 0.01-25.00 μg/L in both human plasma and urine, with correlation coefficients of 0.999 5 and 0.999 7, respectively. The detection limits for plasma and urine were 8 and 6 ng/L, and the lower limits of quantification were 27 and 19 ng/L, respectively. The average recovery rates were 97.00%-100.00% for plasma and 90.00%-96.50% for urine. The within-run relative standard deviations (RSDs) were 4.35%-10.00% for plasma and 2.34%-11.11% for urine, while the between-run RSDs were 6.80%-8.46% and 2.60%-10.00%, respectively. Samples can be stored for seven days at 4 ℃ or -20 ℃. respectively. Samples can be stored for seven days at 4 ℃ or -20 ℃. Matrix effects ranged from 87.12%-99.27% for plasma and 91.00%-97.56% for urine. Conclusion The proposed method is simple, highly sensitive, and reproducible, and is suitable for the determination of 6PPDQ in human plasma and urine samples.

Objective To improve the national standardized method for determining biphenyl in workplace air, which was based on activated carbon tube sampling, carbon disulfide desorption, and gas chromatography, by developing a method using GDX-502 tubes for sampling, toluene for desorption, and gas chromatography. Methods Workplace air samples were collected using GDX-502 sampling tubes and desorbed with toluene, followed by determination with gas chromatography. Results The improved method demonstrated good linearity for biphenyl concentrations ranging from 0.33 to 330.00 mg/L, with a correlation coefficient of 0.999 9. The detection limit and lower limit of quantification were 0.06 and 0.21 mg/L, and the minimum detection concentration and minimum quantification concentration were 0.04 and 0.14 mg/m³ (based on 1.5 L air sample volume), respectively. The average desorption efficiency ranged from 96.6% to 101.1%. The within-run and between-run relative standard deviations were 0.6%-1.4% and 1.4%-3.3%, respectively, with 100.0% sampling efficiency. Samples remained stable for at least 14 days at room temperature. Conclusion The improved method for biphenyl detection demonstrates rapid and accurate performance, with the advantages of low detection limits and high sampling and desorption efficiency.

Objective To summarize the key precautions in the determination of nitrogen oxides (nitric oxide and nitrogen dioxide) in the workplace air and to explore potential optimization items in the national standard analytical method. Methods According to GBZ/T 160.29-2004 Methods for Determination of Inorganic Nitrogen Compounds in the Air Workplace, comparative experiments were conducted to evaluate and optimize critical technical parameters of the standardized method, including the oxidation efficiency of oxidation tubes and the preparation and storage of absorption solutions. The application details of the standard method were refined. Results The concentrations of nitrogen oxides (nitric oxide and nitrogen dioxide) were expressed as nitrogen dioxide equivalents. During calibration, the flow calibrator should be connected to the upstream of the air sampler, and the sampling system should undergo an air tightness check. Each batch of oxidation tubes should be validated before use. Before sampling, both end caps should be removed and the tube should be equilibrated for one hour in a clean environment with 30.00%-70.00% relative humidity. The prepared absorption stock solution in this method can be stored at 4 ℃ for up to 96 days. Commercial porous plate absorption tubes must be batch-validated before use. The sampling flow rate during sampling should be consistent with that specified in the standard method. After sampling, collected samples should be sealed in 10.00 mL amber glass bottles with screw caps and stored at 4 ℃ for up to 120 hours. Conclusion This study summarizes precautions for the sampling, detection, and calculation of nitrogen oxides (nitric oxide and nitrogen dioxide)in workplace air to strengthen quality control. Experimental optimizations of oxidation tube conditioning, absorption stock solution preparation and preservation, and sample storage conditions and durations may provide references for diversifying and simplifying the detection process, which facilitate the practical application in actual work.

Objective To investigate an automated pretreatment technology for detecting levels of free silica in workplace dust. Methods An fully automated pretreatment workstation for detecting free silica levels in workplace dust was developed by integrating graphite-controlled digestion temperature, online-controlled dilution of digestion solutions, and filtration endpoint recognition based on monitoring technology, combined with multi-channel synchronous measurements. Results The fully automatic pretreatment workstation was used to digest and filter 14 standard samples of free silica produced by three institutions, and then detected by pyrophosphate method. The result range of high-, medium-, and low-level free silica standard samples detection was 66.5%-84.8%, 40.0%-44.5%, and 2.1%-24.8%, respectively. The mean relative standard deviations were 3.9%, 1.4% and 1.5%. Conclusion The fully automated pretreatment workstation produced results that met relevant requirements. It can effectively replace the manual digestion and filtration steps of the pyrophosphate method to measure free silica levels in workplace dust and enable rapid detection of free silica in dust samples.

Objective Focusing on gynecological surgery,we constructed a prediction model for surgical duration by extracting features from unstructured surgical planning texts and integrating multimodal data via artificial intelligence technology.Methods The clinical data of 34 614 patients who underwent gynecologic surgeries at West China Second University Hospital,Sichuan University between January 2022 and October 2024 were collected.An embedding-transformer model was constructed to convert surgical planning texts into a one-dimensional numerical feature,referred to as the step feature.The predictive value of the step feature was assessed by comparing the performance improvements of linear regression,random forest,eXtreme Gradient Boosting(XGBoost),support vector regression,K-nearest neighbor regression,and artificial neural network algorithms in two scenarios—with and without the step feature as an input.The out-of-sample prediction accuracy of the models was assessed using mean absolute error(MAE),root mean squared error(RMSE),and R-squared(R2).Furthermore,the model interpretability was examined using SHapley Additive exPlanations(SHAP)values.Results SHAP results showed that the step feature had the highest predictive contribution.Temporal factors in surgical scheduling also influenced gynecological surgery duration.The XGBoost model demonstrated optimal performance on the test set,significantly improving prediction accuracy with a 40.43%increase in R2,while reducing MAE and RMSE by 21.27%and 20.13%,respectively,compared to the baseline model without the step feature.Conclusion The embedding-transformer model developed in this study effectively extracts features from surgical planning texts and enhances the predictive performance of machine learning models.The XGBoost prediction model can assist hospital administrators in implementing more refined management of gynecological surgeries and improving the utilization efficiency of surgical resources.

Objective To establish a method to simultaneously determinate cobalt, nickel, arsenic, molybdenum, silver, cadmium and lead in blood and urine using inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). Methods The blood samples were diluted 20 times with a mixed solution of nitric acid (0.10% V/V) and Triton X-100 (0.02% V/V). The urine samples were diluted 10 times with nitric acid (1.00% V/V). Yttrium-89, rhodium-103, and lutetium-175 were used as internal standards to decrease matrix interference, and either On-Mass mode or Mass-Shift mode was used to decrease mass spectrometry interference, with detection by ICP-MS/MS. Results The linear ranges of the seven elements were 0.100-10.000 μg/L, with the correlation coefficient >0.999 9. The detection limits for the seven elements in the blood and urine were 0.003-0.021 and 0.003-0.031 μg/L, respectively, and the minimum quantification limits were 0.009-0.064 and 0.009-0.094 μg/L, respectively. The recovery rates were 96.64%-102.90% and 96.34%-104.50% for the blood and urine, respectively. The within-run relative standard deviations (RSDs) were 0.32%-2.33% and 0.25%-2.31%, and the between-run RSDs were 1.07%-3.81% and 1.30%-3.62% for blood and urine, respectively. The samples were stable at 4 ℃ for at least 14 days. Conclusion ICP-MS/MS is a simple, sensitive, and accurate method for rapid detection of seven heavy metal elements in the blood and urine of occupational hazard-exposed workers.

Metabolomics, including targeted metabolomics and non-targeted metabolomics, is a method to study endogenous small molecule metabolites in organisms. The process of metabolomics analysis generally includes sample collection and pre-treatment, sample detection, data preprocessing, metabolite identification, data statistical analysis, and others. At present, metabolomics technology has been applied to study toxicological mechanism of occupational hazards, early detection and diagnosis of occupational diseases, screening biomarkers of occupational exposure, and others. The application of metabolomics technology to explore the relationship between workers' metabolites and exposure to occupational hazardous, assess the potential impact of occupational exposure on workers' health, and search for ideal biomarkers or therapeutic targets is conducive to early warning and monitoring of occupational health hazards, and assistance in the early diagnosis and prognosis of occupational diseases.In the future, further research is needed in the field of occupational health using metabolomics to establish more complete and standardized workflows and experimental methods, combine big data technology to explore potential biomarkers, utilize metabolic information to provide precise occupational health services, and use artificial intelligence models for data mining and disease diagnosis in metabolomics.

Objective To analyze the problems and differences in workplace on-site sampling and testing skills in external quality assessment in laboratory among occupational health technical service institutions. Methods A total of 108 occupational health technical service institutions nationwide, participated in the external quality assessment in laboratory of the on-site individual sampling operation skills for silica dust (hereinafter refer to as "silica dust sampling assessment") and on-site detection operation skills for carbon monoxide (hereinafter refer to as " carbon monoxide sampling assessment") in 2023, were selected as the research subjects. The result of the assessment was analyzed. Results The qualification rate of the institutions for the silica dust sampling assessment was 98.1%. The unqualified rate of institutions in the Pearl River Delta region was lower than that in non-Pearl River Delta regions (0.0% vs 11.1%, P<0.017). The excellence rate was higher in public institutions than that in private enterprises (73.5% vs 40.0%, P<0.017). The unqualified rate of institutions with permit was lower than that of institutions without permit (0.0% vs 13.3%, P<0.05). The qualification rate of the institutions for the carbon monoxide sampling assessment was 79.4%. The proportion of the institutes, whose results of carbon monoxide standard gas (gas bag) deviation was >±20.0% was higher in private enterprises than that in public institutions (32.8% vs 7.1%, P<0.017). In terms of the normativity of on-site individual sampling for silica dust, the rates of conducting air tightness checks before sampling, correct disassembly and installation and correct placement direction of dust sampling heads, and correct flow for calibration based on the provided dust sampling heads were low, at 53.7%, 33.3%, and 14.8%, respectively. In terms of the normativity of on-site detection of carbon monoxide, the accuracy rate of converting results by on-site detection individuals was low, at only 57.8%. ConclusionIt is necessary to further strengthen the training of theoretical knowledge and practical skills of individuals in occupational health technical service institutions in Guangdong Province, especially to enhance the capacity of occupational health technical services in non-Pearl River Delta regions of the province.