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 To investigate the clinical application of perioperative human serum albumin(HSA)in cardiac surgery in multiple regions in China,and to evaluate the rationality of its clinical application in conjunction with the clinical guidelines,in order to provide a reference for promoting the rational application of HSA.Methods The medical records of patients who underwent cardiac surgery from April to June 2019 in eight hospitals across the country were retrospectively collected.The statistical information on patients'general information,the dosage,course of treatment,and cost of HSA,and the serum albumin level before and after medication was analyzed to evaluate the use of HSA.Relevant evaluation criteria were established,and the rationality of its medication was evaluated.Results Data from a total of 449 patients were included for analysis,the appropriate rate of medication was 81.1％.The course of medication was mostly＞2-5 days and the total amount of HSA was mostly 50-99 g.The main purpose of medicaiton were improving colloid osmotic pressure,reducing exudation to improve interstitial edema,postoperative volume expansion.Conclusion Clinical attention should be paid to ensure the rational application of HSA in cardiac surgery during the perioperative period and prevent the abuse of blood products.

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.

Objective To establish a method for the determination of thallium and its soluble compounds in workplace air using microporous filter membrane sampling and inductively coupled plasma mass spectrometry (ICP-MS). Methods Thallium and its soluble compounds in workplace air were collected using microporous filter membranes, digested with nitric acid, quantified using lutetium internal standard method, and detected by ICP-MS. Results The linear range of thallium was 0.00 to 600.00 μg/L, with the correlation coefficient of 1.000. The detection limit was 0.08 μg/L, and the lower limit of quantification was 0.26 μg/L. The minimum detection concentration and minimum quantitation concentration of thallium of 75.00 L workplace air were 1.0×10^-5 and 3.0×10^-5 mg/m³, respectively. The minimum detection concentration and minimum quantitation concentration of thallium of 480.00 L workplace air was 2.0×10^-6 and 5.0×10^-6 mg/m³, respectively. The recovery rate of spiking was 100.82%-103.44%, and the relative standard deviation within- and between-batches was 1.50%-3.32% and 1.32%-3.11%, respectively. The sample could be stored at room temperature for at least 14 days. Conclusion This method can be used for the detection of thallium and its soluble compounds in workplace air.

Objective: To investigate the specificity of endogenous metabolic profile in plasma of patients with occupational acute methyl acetate poisoning using non-targeted metabolomics. Methods: A total of six patients with occupational acute methyl acetate poisoning were selected as the poisoning group, while 10 healthy workers without occupational exposure history of chemical hazards in the same industry were selected as the control group using the judgment sampling method. Metabolites in patient plasma of the two groups were detected using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry, and non-targeted metabolomics analysis was performed. Principal component analysis and partial least squares discriminant analysis were used to identify differential metabolites and analyze their metabolic pathways. Results: There were significant differences in metabolite profiles in patient plasma between poisoning group and control group. A total of 195 differentially expressed metabolites were screened in plasma of patients in poisoning group, including 119 upregulated and 76 downregulated metabolites. Lipid substances (lipids and lipid-like molecules) accounted for the highest proportion (21.5%). The differential metabolites of poisoning group were related to folate biosynthesis, amino acid metabolism, pyrimidine metabolism, sphingolipid biosynthesis and other metabolic pathways in plasma compared with the control group (all P<0.05). Conclusion: Occupational acute methyl acetate poisoning affects metabolism of the body. The folic acid biosynthesis, amino acid and lipid metabolism and other pathways may be involved in the occurrence and development of poisoning.

Objective An epidemiological investigation was carried out on the first family cluster epidemic of psittacosis in Wuhan to provide scientific basis for the prevention and control of Chlamydia psittacosis. Methods Epidemiological data were collected by field epidemiological investigation methods, and pathogenic testing was carried out by collecting cases, suspected exposed persons, and environmental samples. Results The 2 cases in the same family stared with fever, headache and chills. The first case was treated in 5 medical institutions and hospitalized in 2 of them. The results of metagenomic next-generation sequencing in the bronchoalveolar lavage fluid of the case indicated that it was infected with Chlamydia psittaci. Thirty environmental samples from cases and 3 pigeon farmers homes, 4 throat swabs from family members of pigeon farmers were collected, and 15 environmental samples were positive by real-time fluorescence quantitative polymerase chain reaction, all of which were in the cases' home and neighbor farmers' homes, including 8 pigeon feces smearing samples, 3 pigeon drinking residual water samples, 1 sand and corn eaten by pigeons, 1 tableware surface smearing sample, and 1 sample of external environment of the patient's home. Conclusions The family cluster epidemic of psittacosis was caused by exposure to the external environment contaminated by Chlamydia psittacosis. Poultry breeding should be regulated to prevent the spread of poultry infection to the human world. At the same time, the awareness of medical staff should be raised, and pathogenic testing should be carried out to confirm the diagnosis for avoiding the occurrence of severe cases and death.

OBJECTIVE: To compare the advantages and disadvantages and application range of three methods for detection of urinary mercury. These methods include alkaline stannous chloride cold atomic absorption spectrometry, acid stannous chloride cold atomic absorption spectrometry and atomic fluorescence spectrometry. METHODS: The detection limits, accuracy and precision in these three methods were compared. RESULTS: The alkaline stannous chloride cold atomic absorption method and acidic stannous chloride cold atomic absorption method had a wide linear range(1.000-10.000 μg/L). The detection limit was high(0.265 and 0.556 μg/L, respectively). The atomic fluorescence spectrometry had the narrowest linear range(0.400-2.000 μg/L) and the lowest detection limit(0.048 μg/L). The average spiked recoveries of the above three methods were 95.93%-101.02%, 92.49%-98.72% and 95.96%-99.57%. The relative standard deviations within and between batches of these three methods were less than 5.00%. The addition recovery of organic mercury by alkaline cold chloride atomic absorption method was 80.91%. The recoveries of inorganic mercury and organic mercury by other methods were close to 100.00%. CONCLUSION: All three methods meet the daily needs of detecting urinary mercury. Among them, alkaline stannous chloride cold atomic absorption method is suitable for promotion in primary laboratories as a preliminary screening method. The atomic fluorescence spectrometry is suitable for the detection of microscale and trace amount of urinary mercury.

OBJECTIVE: To evaluate the ability of health emergency drill for sudden poisoning incidents in Guangdong Province. METHODS: A double-blinded method was used to organize 22 teams in Guangdong Province to conduct a health emergency drill which contained preliminary and repeated drill. The preliminaries contained blind sample analysis,theoretical examination and skills assessment. The repeated drills was desktop network exercise carried out for the teams ranked top 10 in the preliminaries. RESULTS: In the preliminary round,the median( M) of total score among the 22 teams was 72. 5. Among them,blind sample analysis,theoretical examination and skills assessment were 71. 0,61. 4 and 76. 5,respectively. The total score of skill assessment was higher than that of theoretical assessment( P < 0. 05). The passing rate of 22 teams was 68. 2%(15/22),and the failure rate was 31. 8%(7/22). The failing teams all came from the nonPearl River Delta region. The total preliminary scores,passing rate,the total scores of blind sample analysis and skills assessment of the teams in Pearl River Delta Region were higher than that in the non-Pearl River Delta region( P < 0. 01).In the theoretical examination,the scores of detection and investigation were both higher than that of medical rescue( P <0. 05). For the skills assessment,the scores of decision-making,personal protection and poisoning detection were in the top three,the scores of the medical rescue and investigation were relatively low( P < 0. 05). In the repeated round,the M of desktop exercise was 55. 0,passing rate was 20. 0%,and the failure rate was 80. 0%. CONCLUSION: The health emergency response capacity for sudden poisoning incidents in Guangdong Province needs to be improved. The construction of emergency response capacity for emergency poisoning in the non-Pearl River Delta region should be strengthened,especially the training on strengthening theoretical and practical knowledge of poisoning medical treatment and poisoning investigation.

OBJECTIVE: To explore an objective evaluation mode for emergency response capacity on sudden poisoning incidents. METHODS: Based on the health emergency drills and blind design,22 teams in Guangdong Province were recruited to participate in the first round of evaluation,including blind sample analysis,theoretical examination( poisoning medical rescue,detection and investigation) and skills assessment( poisoning medical care,poisoning investigation,personal protection,poisoning detection and emergency decision-making). Then,the top 10 teams in the first round of evaluation were proceeded to desktop exercise in the second round of evaluation. The evaluation results were compared with the local gross domestic product( GDP) from 2011 to 2015 by Spearman rank correlation analysis. RESULTS: The median scores of the 4 sections were as follows: blind sample analysis was 71. 0,theoretical examination was 61. 4,skills assessment was 76. 5,and the desktop exercise was 55. 0. The rates of excellent for assessment of blind sample analysis,theoretical examination and skills assessment were 22. 7%,4. 5% and 0. 0%,while the failure rates were 31. 8%,45. 5% and 4. 5%,respectively. The rates of failure in medical rescue and investigation in theoretical examination were63. 6% and 50. 0%,the rates of failure in medical rescue and investigation in skills assessment were 40. 9% and 31. 8%,respectively. The middle-grade and passing rates of the top 10 teams in the desktop exercise were 10. 0%,and the failure rate was 80. 0%. There was a moderate positive correlation between the emergency response capacity for emergent poisoning and local GDP( Spearman rank correlation coefficient > 0. 700,P < 0. 05). CONCLUSION: The evaluation mode of emergency response capability assessment combined with actual combat and desktop emergency drill is established successfully. It can objectively test the assessment of emergency response capabilities.

OBJECTIVE: To evaluate the technical level and ability of the detection of free silica in dust in occupational health technical service institutions of Guangdong Province through inter-laboratory comparison. METHODS: The interlaboratory detection of free silica in dust in 55,61,58 and 66 occupational health technical service institutions were carried out and compared in 2012-2015. The results were statistically analyzed by four points robust statistical technique,and the relative deviation between the laboratory test results and the Median of them was used as the auxiliary evaluation index of the laboratory's technical ability. RESULTS: The stable coefficient of variation(CV) of samples with free silica content > 20. 00% was less than 5. 00%,and the stable CV of samples with free silica content ≤20. 00% was more than5. 00%. The qualified rate in 2012-2015 were 89. 09%,81. 97%,77. 59% and 81. 82%,respectively. There was no statistical difference(P > 0. 05) in the annual reference between private and non-private institutions compared to the qualified rate in 2012-2015. There was no statistical difference(P > 0. 05) in the qualified rate of the institutions in the Pearl River Delta region and in the non-triangular regions of the Pearl River Delta in 2012-2015. CONCLUSION: Comparison of the detection technology service ability in the detection of free silica in dust should be conducted to improve its technical service quality.