Objective To analyze the prevalence status of cardiometabolic risk factor (CMRF) and its aggregation among workers engaged in new forms of employment. Methods A total of 5 429 new employment workers (including couriers, online food delivery workers, and ride hailing drivers) who underwent health medical examinations at a tertiary hospital in Beijing City were selected as the research subjects using the judgment sampling method. Data on waist circumference, blood pressure, blood glucose, and blood lipid levels were collected to analyze their CMRF [central obesity, elevated blood pressure, elevated blood glucose, elevated triglycerides, and reduced high-density lipoprotein cholesterol (HDL-C)] and their aggregation (with ≥ 2 of the above 5 risk factors) status. Results The detection rates of central obesity, elevated blood pressure, elevated blood glucose, elevated triglycerides, and reduced HDL-C were 61.2%, 38.2%, 29.5%, 40.9% and 22.6%, respectively. The detection rates of CMRF aggregation was 57.8%. The result of multivariable logistic regression analysis showed that male, age ≥45 years, smoking, overweight, and obesity were risk factors for CMRF aggregation (all P<0.05). Conclusion The detection rate of CMRF and its aggregation among workers with new forms of employment in Beijing City is relatively high. Targeted prevention and control efforts should be strengthened for high-risk populations, especially males, workers aged ≥45 years, smokers, and those who are overweight or obese.

Objective To compare H_p(3) calibration with a homemade (A) thermoluminescent dosimeter (TLD) and an imported (B) TLD in a standard X-ray RQR radiation field, to explore the different responses of A and B, and to provide foundation for the calibration of H_p(3). Methods A column mode was selected. H_p(3) calibration was performed using A and B in a standard X-ray RQR radiation field in the Secondary Standard Dosimetry Laboratory, National Institute for Radiological Protection, China Center for Disease Control and Prevention. Angle response, energy response, and linear response were calibrated with RQR4 (60 kV), RQR7 (90 kV), and RQR9 (120 kV), respectively. Results In terms of angle response, the calibration results of A were relatively high, while the calibration results of B were relatively low. In terms of energy response, the calibration results showed a similar pattern to angle response. In terms of linear response, the calibration results of both A and B were satisfactory. Conclusion Both A and B can be used for normal calibration of H_p(3) in a standard X-ray RQR radiation field. However, in actual monitoring, attention should be paid to the energy and angle response values of TLDs.

Objective To analyze the evaluation results of health enterprises in Beijing City and their influencing factors. Methods A total of 40 enterprises that passed the health enterprise evaluation in Beijing from 2021 to 2022 were selected as the study subjects using the judgment sampling method. The total evaluation scores and influencing factors were analyzed based on the size, nature, industry classification, and establishment time of the enterprises. Results The total evaluation score of the 40 health enterprises was (553.1±18.4) points. Scores for the primary evaluation indicators, including management organization and system, occupational disease prevention measures, health environment, health promotion measures, prevention measures for occupational stress caused damage, and musculoskeletal injury prevention measures, were (94.0±4.8), (94.0±4.3), (94.5±3.8), (89.7±4.8), (89.6±4.6), and (91.4±5.9) points, respectively. The result of multiple linear regression analysis showed that, large enterprises had higher total evaluation scores than medium enterprises and micro and small enterprises after controlling for confounding factors such as industry classification and establishment time (all P<0.10). The total evaluation scores of private enterprises and foreign-funded enterprises were lower than that of state-owned or state-participated enterprises (all P<0.10). Conclusion Enterprise size and nature are influencing factors for the total evaluation score of health enterprises. It is necessary to enhance resource and policy support for medium-sized, micro and small enterprises and private enterprises to improve the development of the health enterprises.

The cell nuclear damage is mainly caused by the radiation and various carcinogenic compounds, the essence of the damage is molecular adhesion fracture and chemical modification. After nuclear damage, the cells whose nuclei may be abnormal in morphology, structure and function, then become a kind of morbid cells or defective cells. The cell nuclear damage can affect gene expression and regulation, leading to dysfunctions or abnormalities of transcription and protein synthesis, which results in aging and induces various chronic refractory diseases, such as hypertension, atherosclerosis, diabetes, Alzheimer's disease, autoimmune diseases, and so on. The cell nuclear damage can also affect the state of cell differentiation and lead to restart of genes related to division and proliferation, thus inducing cancer. The cancer cells are derived from the cells with nuclear abnormalities, and the biological behavior or characteristics of cancer cells (shedding and metastasis, immune tolerance, uncontrolled, loss of contact inhibition, etc.) are derived from cells with nuclear abnormalities. This article reviewed the chronic refractory diseases caused by nuclear damage and their mechanisms, which provided a new idea for occupational health and toxicology research, as well as a new method and strategy for occupational disease prevention and treatment.

Compared with conventional radiotherapy, FLASH radiotherapy has advantages in protecting normal tissues, while the dose rate is increased by more than 100 times. If the shielding design of the treatment room is carried out according to the existing standard, the thickness and cost of the shielding wall will be significantly increased, or even hardly to meet the requirement of the standards, resultsing in the failure of the application of FLASH radiotherapy. By investigating the domestic and foreign standards and literature, this paper analyzes the challenges brought by FLASH radiotherapy technology to the shielding design of radiotherapy treatment room in China. Dose rate control standards adopted by different countries in the shielding design are emphatically compared as well. In several countries, the average dose rate under the actual treatment conditions was considered in the shielding design. In China, the method of instantaneous dose rate taking acount of occupancy factor is adopted. However, if FLASH radiotherapy technology is applied, the requirement of instantaneous dose rate will be difficult to meet. In order to improve the high dose rate radiotherapy technology such as FLASH radiotherapy, the revision of the existing standards is advised if the authorized limits are not changed. To use the average dose rate limit within a certain period of time for control, or to raise the control standard in the case of flash radiotherapy, are also avaliable.

The cell nuclear damage is mainly caused by the radiation and various carcinogenic compounds, the essence of the damage is molecular adhesion fracture and chemical modification. After nuclear damage, the cells whose nuclei may be abnormal in morphology, structure and function, then become a kind of morbid cells or defective cells. The cell nuclear damage can affect gene expression and regulation, leading to dysfunctions or abnormalities of transcription and protein synthesis, which results in aging and induces various chronic refractory diseases, such as hypertension, atherosclerosis, diabetes, Alzheimer's disease, autoimmune diseases, and so on. The cell nuclear damage can also affect the state of cell differentiation and lead to restart of genes related to division and proliferation, thus inducing cancer. The cancer cells are derived from the cells with nuclear abnormalities, and the biological behavior or characteristics of cancer cells (shedding and metastasis, immune tolerance, uncontrolled, loss of contact inhibition, etc.) are derived from cells with nuclear abnormalities. This article reviewed the chronic refractory diseases caused by nuclear damage and their mechanisms, which provided a new idea for occupational health and toxicology research, as well as a new method and strategy for occupational disease prevention and treatment.

Background Gene sequencing industry is an emerging innovation-driven industry. Employees have high requirements for independent learning and innovation ability and face great professional pressure. Objective To understand the occupational stress, depression, and sleep of gene sequencing enterprise employees and to analyze the effect of occupational stress on depression and sleep. Methods From November to December 2021, occupational stress, depression, and sleep conditions of 469 workers from 34 enterprises in gene sequencing industry were surveyed by Core Occupational Stress Scale (COSS), Patient Health Questionnaire 9 (PHQ-9), and Pittsburgh Sleep Quality Index (PSQI). A total of 427 valid questionnaires were recovered with a questionnaire valid response rate of 91.04%. The relationship of occupational stress with depression or sleep was analyzed by logistic regression. Results The rates of occupational stress, depression, and sleep disorder were 27.40%, 33.50%, and 28.10%, respectively. Significant difference were found in the rates of depression and sleep disorder in different occupational stress groups (P<0.05). The results of logistic regression analysis showed that, for every 1 increase in social support score, the risk of depression increased by 1.206 (95%CI: 1.117−1.304), and the risk of sleep disorder increased by 1.143 (95%CI: 1.059−1.233). For every 1 increase in organization and reward score, the risk of developing depression increased by 1.082 (95%CI: 1.017−1.151). Mild, moderate, and severe occupational stress were all associated with a higher risk of depression in reference to no occupational stress (OR=2.535, 95%CI: 1.465−4.386; OR=3.774, 95%CI: 1.809−7.870; OR=3.823, 95%CI: 1.486−9.837). Severe occupational stress was associated with a higher risk of sleep disorder in reference to no occupational stress (OR=3.141, 95%CI: 1.233−8.006). Conclusion Occupational stress among employees in the gene sequencing industry can increase the risks of depression and sleep disorder. Enterprises need to take intervention measures and pay attention to prevention and treatment.

Objective To simplify and optimize the micronucleus test method. Methods The preparation process of micronucleus test was simplified and optimized. In the improved method, the superfine solution was directly absorbed and discarded after cell culture, and then potassium chloride solution was added for hypotonic treatment. Then pre-fixation, centrifugation. Once the centrifugation was completed, the cells which fixed only once were directly dropped to the slide. Results The background of the slides was clear and the cells were slightly darker, but the observation of cells and micronucleus was not affected. There were a lot of binuclear cells, which can meet the counting requirements. With oil and high magnification, the image wais clearer and the background was cleaner. The cytoplasmic integrity rate, cell stain rate and the average number of cells per high magnification field of cells by the improvement method were significantly increased compared with that by the traditional methods, the probability P values were 0.0051 (χ²=7.8375), 0.0140 (χ²=6.0437) and 0.0025 (t=3.0951), respectively. The rate of micronucleus cells and cells group index had no statistical significance compared with the traditional method, the probability P values were 0.7749 (χ²=0.0817) and 0.5152 (U =0.0000), respectively. Conclusion The new method is more simple, easier to control the test quality, more reliable test results, and save time, manpower and material resources.

Objective:To study the effects of combined occupational exposure of benzene, toluene, and xylene on human metabolism at an overall level, and to screen biomarkers related to the combined occupational exposure of benzene, toluene, and xylene, and to explore the mechanism of early health effects preliminarily caused by combined occupational exposure of benzene, toluene, and xylene by identification of biomarkers and retrieval of metabolic pathways.Methods:A shoe-making company was selected as the research site. Twenty subjects for the exposed group and the control group were selected separately, and urine of the subjects was collected. The metabolic profiles of the samples were collected by liquid chromatography time-of-flight mass spectrometry, and professional metabolomics and multivariate statistical analysis software were used to establish PCA and OPLS-DA analysis models to screen potential biomarkers and identify biomarkers. Finally, based on the dynamic changes and trends of potential biomarkers between groups, the mechanism of body damage caused by benzene, toluene, and xylene was initially explored.Results:Urine metabolomics analysis showed that the metabolic profile of urine samples of the benzene, toluene, and xylene combined exposure group was different from that of the control group. 27 potential biomarkers that were closely related to the combined exposure of benzene, toluene, and xylene were screened and identified. These potential biomarkers were enriched in 16 metabolic pathways, of which 3 pathways were significantly enriched ( P<0.05) , respectively, lysine metabolism, amino sugar metabolism, and nucleotide sugar metabolism. Conclusion:The metabonomics method can well reflect the changes in the metabolome of urine samples in the occupational population after the combined exposure of benzene, toluene, and xylene, which will help us better evaluate the risk of combined exposure of benzene, toluene, and xylene and prevent and control their health risks.

Objective:To investigate the effects of titanium dioxide nanoparticles (TiO 2 NPs) on urine metabolites in occupationally exposure people based on metabolomics technology, and to explore the mechanism of early health effects of TiO 2 NPs on occupational exposure. Methods:In October 2019, the TiO 2 NPs occupational exposure population was selected as the research object, of which 64 people were in the exposure group who had been engaged in TiO 2 NPs exposure positions for more than 1 year; the control group was 62 people, who were logistics administrative staff of the same company. The urine of the research subjects before class was collected, using the ultra-high performance liquid chromatography time-of-flight mass spectrometer to collect the metabolism data of the urine, Progenesis QI software for data preprocessing and metabolite identification, SIMCA-P software for the principal component analysis of the data and potential biomarkers screening, MetaboAnalyst 4.0 software for metabolic pathway enrichment analysis. Results:The urine metabolism profile of workers in the exposure group was different from the control group, and 44 potential biomarkers were screened and identified. These potential biomarkers were significantly enriched in three pathways ( P<0.05) , namely D-arginine and D-ornithine metabolism pathway, nitrogen metabolism pathway and D-glutamine and D-glutamate metabolism pathways. Conclusion:The occupational exposure of TiO 2 NPs can affect the concentration of metabolites in people urine and metabolic pathways, which provides a direction for the study of occupational hazard mechanisms of TiO 2 NPs and the monitoring of health risks.