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 investigate the role of cytochrome P450 2E1 (CYP2E1) in trichloroethylene (TCE)-induced skin sensitization and liver damage in guinea pigs, using diallyl sulfide (DAS), a CYP2E1 inhibitor, as an intervention. Methods Specific pathogen-free female guinea pigs were randomly divided into blank control group, solvent control group, positive control (2,4-dinitrochlorobenzene) group, TCE-exposure group, and DAS-intervention group. Skin sensitization experiments were conducted using the guinea pig TCE maximal dose-skin sensitization test. Urinary trichloroacetic acid levels were determined following TCE induction and challenge. At 48 hours after the final challenge, serum liver function markers and inflammatory cytokines levels were detected. Histopathological examination on skin and liver tissues was performed, and hepatic CYP2E1 protein expression and oxidative stress indicators were assessed. Results The sensitization rates of guinea pigs were 100.0%, 75.0%, and 33.3% in the positive control, TCE-exposure, and DAS-intervention groups, respectively, while the blank control and solvent control groups were both 0.0%. Compared with the guinea pigs in TCE-exposure group, those in the DAS-intervention group had lower urinary trichloroacetic acid levels at intradermal induction, local induction, first challenge, and 24 hours after the final challenge time point (all P<0.05). Histopathology of guinea pigs showed dermal inflammatory infiltration and basal keratinocyte necrosis in the TCE-exposure group, whereas only mild dermal inflammation was observed in the DAS-intervention group. The guinea pigs in TCE-exposure group exhibited diffuse hepatocellular necrosis, while hepatic damage in the DAS-intervention group was alleviated, characterized by only mild hepatocellular steatosis and hepatocyte swelling around the central vein. The skin sensitization rate of guinea pigs in the TCE-exposure group increased (all P<0.01), the serum alanine aminotransferase (ALT )activity, the levels of interleukin (IL)-2, IL-17, and tumor necrosis factor-α (TNF- α) increased (all P<0.05), the relative expression of CYP2E1 protein, the activity of superoxide dismutase (SOD), and the level of malondialdehyde in liver tissue increased (all P<0.05), while the activity of catalase decreased (P<0.05), compared with the blank control and solvent control groups. The serum ALT activity and the levels of IL-2, IL-17, and TNF-α of guinea pigs in DAS-intervention group reduced (all P<0.05), as well as CYP2E1 protein expression, SOD activity, and malondialdehyde level in liver tissue reduced (all P<0.05), compared with the TCE-exposure group. Conclusion TCE can induce hepatic CYP2E1 expression, thereby promoting oxidative stress and inflammatory responses, which contributes to skin sensitization and liver damage. DAS alleviates TCE-induced toxic effects on skin and liver by inhibiting CYP2E1 expression.

ObjectiveTo improve the quality standard of Yuanhu Zhitong oral liquid in order to strengthen the quality control of this oral liquid. MethodThin layer chromatography（TLC） was used for the qualitative identification of Corydalis Rhizoma and Angelicae Dahuricae Radix in Yuanhu Zhitong oral liquid by taking tetrahydropalmatine， corydaline reference substances and Corydalis Rhizoma reference medicinal materials as reference， and cyclohexane-trichloromethane-methanol（5∶3∶0.5） as developing solvent， Corydalis Rhizoma was identified using GF254 glass thin layer plate under ultraviolet light（365 nm）. And taking petroleum ether（60-90 ℃） -ether-formic acid（10∶10∶1） as developing solvent， Angelicae Dahuricae Radix was identified using a silica gel G TLC plate under ultraviolet light（305 nm）. High performance liquid chromatography（HPLC） was performed on a Waters XSelect HSS T3 column（4.6 mm×250 mm， 5 μm） with acetonitrile（A）-0.1% glacial acetic acid solution（adjusted pH to 6.1 by triethylamine）（B） as the mobile phase for gradient elution（0-10 min， 20%-30%A； 10-25 min， 30%-40%A； 25-40 min， 40%-50%A； 40-60 min， 50%-60%A）， the detection wavelength was set at 280 nm， then the fingerprint of Yuanhu Zhitong oral liquid was established， and the contents of tetrahydropalmatine and corydaline were determined. ResultIn the thin layer chromatograms， the corresponding spots of Yuanhu Zhitong oral liquid， the reference substances and reference medicinal materials were clear， with good separation and strong specificity. A total of 12 common peaks were identified in 10 batches of Yuanhu Zhitong oral liquid samples， and the peaks of berberine hydrochloride， dehydrocorydaline， glaucine， tetrahydropalmatine and corydaline. The similarities between the 10 batches of samples and the control fingerprint were all >0.90. The results of determination showed that the concentrations of corydaline and tetrahydropalmatine had good linearity with paek area in the range of 0.038 6-0.193 0， 0.034 0-0.170 0 g·L^-1， respectively. The methodological investigation was qualified， and the contents of corydaline and tetrahydropalmatine in 10 batches of Yuanhu Zhitong oral liquid samples were 0.077 5-0.142 9、0.126 1-0.178 2 g·L^-1， respectively. ConclusionThe established TLC， fingerprint and determination are simple， specific and reproducible， which can be used to improve the quality control standard of Yuanhu Zhitong oral liquid.

ObjectiveTo understand the monitoring result of occupational hazard in the workplace of key industries in Guangdong Province from 2020 to 2023. Methods The data of occupational hazards in the workplace of 20 key industries in Guangdong Province from 2020 to 2023 were collected from the “Workplace Occupational Hazard Monitoring System” of the Chinese Disease Prevention and Control System subsystem. The monitoring result of occupational hazard factors, occupational health training, occupational health examination, occupational protection, detection of occupational hazardous agents such as dust, chemical substances and noise were analyzed. Results A total of 13 058 enterprises from key industries were recruited as the monitoring subjects in Guangdong Province. There were 290 large-, 1 342 medium-, 7 635 small-, and 3 791 micro-enterprises, with small and micro-enterprises accounting for 58.5% and 29.0% of the total, respectively. A total of 7 542 enterprises exceeded the national standard in the detection of occupational hazards, with a rate of 57.8%. A total of 1 942 517 workers from 13 058 enterprises were recruited, with 835 567 workers were exposed to occupational hazards, with a rate of 43.0%. The rate of occupational health training for enterprise leaders, occupational health management personnel, and workers was 71.9%, 73.8%, and 86.5%, respectively. The abnormal rate of occupational health examinations for workers exposed to noise, dust, and chemical agents was 2.0%, 0.6%, and 1.0%, respectively. The distribution rate of dust masks, anti-poisoning masks or face masks, and noise prevention earplugs or earmuffs was 83.3%, 71.3%, and 77.8%, respectively. The rate of installation of dust prevention facilities, anti-poisoning facilities, and noise prevention facilities was 85.6%, 81.2%, and 50.1%, respectively. The rate of exceeded the national standard of dust, noise in the worksites/types and workplaces showed a decreasing trend year by year (all P<0.01), while the rate of exceeded the national standard of chemical agents in worksites/types and workplaces showed an increasing trend year by year in various occupational hazards (all P<0.01). Conclusion Occupational hazards in the workplace of key industries in Guangdong Province are relatively common. The proportion of workers exposed to occupational hazards is relatively high. It is necessary to further improve the use of noise prevention facilities and protective equipment, strengthen occupational health training for enterprises throughout the province and regularly monitor occupational hazards to reduce the risk of occupational diseases.

ObjectiveTo establish a method for the determination of 1,1,1,2-tetrachloroethane (TeCA) and 1,1,2,2-TeCA in human urine using liquid-liquid extraction-gas chromatography. Methods The 5.0 mL urine sample was mixed with 2.0 g anhydrous sodium sulfate and 5.0 mL ethyl acetate, then vortexed mixing. The 1.0 mL extraction was separated by 100% dimethylpolysiloxane capillary gas chromatography column, detected by flame ionization detector, and quantified by an external standard method. Results The linear ranges of 1,1,1,2-TeCA and 1,1,2,2-TeCA were 0.250-50.750 mg/L, with both correlation coefficients of >0.999 9. The detection limit of 1,1,1,2-TeCA in urine was 0.020 mg/L, and the lower limit of quantification was 0.060 mg/L. The average recovery was 88.02%-101.32%, and the within-run and between-run relative standard deviations (RSDs) were 0.11%-0.47% and 0.39%-1.09%, respectively. The detection limit of 1,1,2,2-TeCA in urine was 0.050 mg/L, and the lower limit of quantification was 0.150 mg/L. The average recovery was 93.42%-101.32%, and the within-run and between-run RSDs were 0.28%-1.04% and 0.50%-1.03%, respectively. Both the 1,1,1,2-TeCA and 1,1,2,2-TeCA cannot be stored at room temperature. The 1,1,2,2-TeCA can be stored at 4 ℃ for at least three days. At -20 ℃, the 1,1,1,2-TeCA can only be stored for one day, while 1,1,2,2-TeCA can be stored for at least five days. Conclusion This method has high sensitivity, good specificity, simple sample pretreatment, and more intuitive and reliable results. It can be used to determine the level of 1,1,1,2-TeCA and 1,1,2,2-TeCA in urine of occupational population.

AIM: To compare the short-term postoperative visual acuity, visual disturbance phenomena, and spectacle independence rate in patients who underwent monocular implantation with trifocal, multifocal, or extended range of vision intraocular lens(IOL).METHODS: A retrospective analysis was conducted on 67 cataract patients(67 eyes)who underwent phacoemulsification cataract extraction combined with IOL implantation from March 2019 to December 2022. A total of 35 cases(35 eyes)received Symfony extended range of vision IOL implantation, 21 cases(21 eyes)received AcrySof IQ ReSTOR +3D multifocal IOL, and 11 cases(11 eyes)received AcrySof IQ PanOptix trifocal IOL. The preoperative uncorrected distance visual acuity(UDVA), uncorrected intermediate visual acuity(UIVA), and uncorrected near visual acuity(UNVA)and 3 mo postoperatively were documented. Moreover, defocus curves, visual disturbance phenomena, and spectacle independence rates were recorded at 3 mo postoperatively.RESULTS: At 3 mo postoperatively, no statistically significant differences were observed in UDVA among the three groups(P>0.05). A comparison of UIVA showed superior results in the Symfony and PanOptix groups compared to the ReSTOR group(all P<0.01). The UNVA of both the ReSTOR and PanOptix groups outperformed the Symfony group(all P<0.01). The defocus curves indicated that in the intermediate vision range(-1.00 to -1.50 D), the Symfony group exhibited better performance than the ReSTOR group(P<0.05); while in the near vision range(-2.50 to -3.50 D), the ReSTOR group was superior to the Symfony group(P<0.05). The PanOptix group demonstrated superior visual acuity in the near vision range(-2.00 to -3.50 D)compared to the Symfony group(P<0.05)and was also superior in the intermediate vision range(-1.00 to -2.00 D)compared to the ReSTOR group(P<0.05). No significant differences were observed in the incidence of glare or halo and binocular interference phenomena among the three groups(P>0.05). The PanOptix and ReSTOR groups exhibited a higher spectacle independence rate compared to the Symfony group(P<0.0167).CONCLUSION: Compared to Symfony extended range of vision IOL and ReSTOR multifocal IOL, PanOptix trifocal IOL offers a balanced approach to distance, intermediate, and near visual acuity, without a high incidence of glare and halo, and with a higher spectacle independence rate. Caution is still advised when considering monocular implantation with presbyopia-correcting IOLs.

Objective To investigate and analyze a group occupational acute dimethylacetamide (DMA) poisoning incident occurred during the post-fire cleaning operation in a spandex manufacturing enterprise. Methods This study focused on the involved enterprise, employing units, poisoning patients, and workers with similar occupational exposure history from a group occupational acute chemical poisoning incident in Guangdong Province in 2023. Occupational health on-site investigation data, clinical records of poisoned patients, and occupational disease diagnostic data were collected to determine the cause of the poisoning. Results The incident occurred at a spandex manufacturing enterprise during the cleaning of polymerization reaction vessels after a fire, resulting in poisoning of six cleaning workers. The clinical symptoms of patients included varying degrees of liver function abnormalities and skin damage. All six patients wore long-tube air-supplied full-face masks during work. The patients were in a confined work space with poor ventilation, and worked more than 8 hours per day. Patients felt unwell after 5-13 days of work. Post-incident investigation revealed that the DMA exposure concentration of short term near the reaction vessels was 36.06 mg/m³. DMA accounted 13.74% to 30.09% of the volatile organic compounds in the raw and auxiliary materials and waste in the vessel. N-methylacetamide was detected in the urine of these six patients, with levels up to 1 639.78 mg/g creatinine, exceeding the occupational exposure limit (20.00 mg/g creatinine). All six patients were diagnosed as occupational acute DMA poisoning. Conclusion Occupational acute DMA poisoning mainly causes liver damage, has a latent onset, and poses a risk of group occurrence. The main causes of group poisoning are confined work space, inadequate management, insufficient protective measures, and excessive working hours.

Biotoxins, which include bacterial, fungal, marine, plant, and animal toxins, are widespread in living and occupational environments, posing potential threats to human health. Rapid detection of biotoxins in blood is crucial for preventing health hazards and enabling timely disease diagnosis and treatment. Biosensors and immunoassay technologies have critical advantages in the rapid detection of biotoxins in blood. Common biosensors, such as surface plasmon resonance biosensors and fluorescent biosensors, enhance sensitivity and reduce detection limits through signal amplification. Common immunoassay methods, such as colloidal gold immunochromatography, fluorescence immunochromatography, and chemiluminescence immunoassay, improve detection efficacy and sensitivity through specific antibody-antigen binding and nanotechnology. However, current rapid detection technologies of bitoxins in blood face challenges such as matrix interference and insufficient specificity, and they fall short in high-throughput detection of multiple toxins simultaneously. Future developments should focus on improving sample pretreatment, innovating signal amplification methods, enhancing specificity on recognition of elements, and designing portable detection devices and high-throughput platforms for simultaneous toxin analysis. These advancements aim to improve the sensitivity and reliability of detection methods, providing more accurate and convenient solutions for biotoxin detection in blood.

{L-End}Objective To establish a method for the simultaneous determination of dimethyltin (DMT), trimethyltin (TMT), diethyltin (DET), and triethyltin (TET) in human whole blood using high performance liquid chromatography-inductively coupled plasma-mass spectrometry (ICP-MS). {L-End}Methods The 1.0 mL of blood was added with 4.0 mL 65% aqueous solution (containing 6% acetic acid), extracted and separated by C₄ column (150 mm×3 mm×3 μm) using a mobile phase of methanol and 4% acetic acid aqueous solution (containing 0.25 mmol/L tropolone) at a volume ratio of 35∶65, and detected by ICP-MS. {L-End}Results The linear range of DMT, TMT, DET, and TET was 30.60-550.80, 29.00-522.00, 46.10-829.80, and 34.05-612.90 μg/L, respectively. All correlation coefficients were 0.999. The detection limit of DMT, TMT, DET and TET was 21.40, 20.30, 32.27 and 23.80 μg/L, respectively. The recovery rate was 81.9%-104.9%. The within-run and between-run relative standard deviation was 1.6%-6.9% and 0.1%-10.0%, respectively. The samples can be stored at -20 ℃ and 4 ℃ for at least three days. {L-End}Conclusion This method can be used for trace analysis of DMT, TMT, DET, and TET in whole blood.

Objective To establish a rapid qualitative analysis method for volatile organic components in chemicals. Methods Headspace gas chromatography-mass spectrometry was used to qualitatively determine 19 volatile organic components, including benzene, 1,2-dichloroethane, and n-hexane, in chemicals. Different sample amounts, heating temperatures, heating times, and sample volumes were analyzed to assess their effects on detection results and optimize sampling conditions. Results Based on the set chromatography, the optimal sampling process of this method was as follows： 5.0 g sample in a 20.0 mL headspace bottle, incubated at 40 ℃ for 30 minutes in a constant-temperature drying incubator, and a 1.00 mL headspace gas injection. The within-run and between-run relative standard deviations of all components ranged from 0.00% to 21.05% and 0.00% to 33.33%, respectively. The samples stored in sealed glass containers were stable at room temperature for at least 60 days. Conclusion This method offers simplicity, good reproducibility, and stability, making it suitable for rapid qualitative analysis of volatile organic components in chemicals.