Toluene diisocyanate exposure induces oxidative stress injury in rat lung / 公共卫生与预防医学

Objective To investigate the effect of subchronic inhalation of toluene diisocyanate (TDI) on oxidative stress damage in rat lung tissue. Methods SPF-grade Sprague-Dawley male rats were randomly divided into 4 groups,the rats were placed in a HOPE-MED 8050A movable poison cabinet in a cage.To observe the ultrastructural and histopathology changes of lung tissue in rats.The levels of reduced glutathione (GSH), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) in lung tissue were detected. The ultrastructural and histopathological changes were examined. The expression levels of HO-1 mRNA and protein were detected by Real-time PCR and Western Blot, respectively. Results The body mass, lung tissue mass, and lung organ coefficient of rats in each dose group were lower than those in the control group (P0.05). Conclusion Subchronic inhalation of TDI can cause changes in the pathology and ultrastructure of rat lung tissue, leading to abnormal levels of metabolic enzymes in lung function, thereby inducing oxidative stress damage to the lungs. However, but HO-1 is involved in oxidative stress damage in the lungs induced by TDI.

Media surveillance of occupational chemical incidents in 2021 / 公共卫生与预防医学

Objective To understand the occurrence characteristics of occupational chemical incidents in China by media surveillance, to provide scientific evidences for formulating effective prevention and control strategies, and to provide new ideas for public surveillance and early warning of chemical incidents. Methods Occupational chemical incidents were collected and sorted through the Internet every day. The statistical analysis was conducted from time, region, industry, and causes of the collected incidents. Results A total of 99 occupational chemical incidents were collected in 2021, involving 356 peoples and 186 deaths. April to July was the high incidence period of events, mainly limited space poisoning and asphyxiation events. Majority of the incidents were general grade events, mainly occurring in small and medium enterprises. Guangdong Province had the most incident reporting areas. Incidents mainly occurred in chemical raw material and chemical product manufacturing industry as well as in water production and supply industry, mainly in manufacturing, cleaning and maintenance positions. The main types of poisons were asphyxiating gases and organic solvents, mainly involving hydrogen sulfide and benzene. The incidents could have been caused by lack of safety awareness, leakage of equipment, and lack of protective measures. Conclusion Occupational chemical incidents still occur frequently and cause serious harm. It is suggested that the relevant departments and employers should strengthen supervision and management, effectively manage and control operational risks, and increase supervision of key industries and positions, to ensure the health and safety of workers.

Survey on current status of noise hazards in key industries in Tianjin in 2020 / 公共卫生与预防医学

Objective To conduct a survey on the status of noise hazards in Tianjin in 2020, to analyze the main distribution characteristics of noise hazards, and to put forward corresponding preventive and control measures. Methods A unified questionnaire was used to investigate the city-wide enterprises with more than 5 employees, normal production and operation, and noise hazards. The χ2 test was used to analyze the survey results. Results There were 8 560 enterprises with noise hazards, which were concentrated in the five outer suburban districts, the four districts around the city and the Binhai New Area, mainly small and medium-sized enterprises. Totally, 223 800 people were exposed to noise. The rates of noise hazard detection and physical examination of workers were 25.88% and 17.66%, and the rate of over standard detection and the rate of abnormal physical examination were 13.09% and 1.62%, respectively. The differences in noise detection rate, over standard detection rate and physical examination rate were significant in different administrative regions, enterprise scales and industries. The detection rate and physical examination rate of enterprises in the five outer suburban districts, micro-scale enterprises, and paper products industries were the lowest, while the rate of exceeding standards was the highest in the railway, shipping, aerospace and other transportation equipment manufacturing industries. Conclusion Noise is a common occupational hazard in enterprises in Tianjin. There are a large number of people who are exposed to noise. The detection rate and physical examination rate of noise are at a low level. Individual industries have a high rate of exceeding the standard. The current situation of noise hazard prevention and control is not optimistic. It is recommended to pay attention to it and take effective intervention measures.

Case study of occupational benzene poisoning and application of GC-MS / 公共卫生与预防医学

Objective To analyze the diagnosis cases of occupational benzene poisoning in gas station industry, and to explore the application of GC-MS technology in occupational disease diagnosis.   Methods The epidemiological method was used to describe and analyze the occupational disease diagnosis of 15 gas station workers , and qualitative screening of occupational hazard factors was performed by GC-MS.   Results All the 15 workers had more than one year's occupation history of oil refueling and unloading.  The clinical manifestations were consistent with the characteristics of chronic benzene poisoning in diagnosis of occupational benzene poisoning.  However, due to lack of evidence of occupational exposure to benzene and incomplete diagnostic data, occupational chronic benzene poisoning was not diagnosed. GC-MS technology was used to screen the occupational hazard factors in the gas station workplace, and benzene, n-pentane, n-hexane and so on were found.  Conclusion GC-MS is recommended for qualitative screening of organic solvents such as benzene when diagnosing occupational diseases for gas station workers , so as to accurately identify occupational hazard factors in workplaces and provide reliable basis for diagnosis of occupational diseases.

Tonstruction of AHI based on the integrating health risks of exposure to air pollution and ambient temperature in Tianjin / 公共卫生与预防医学

Objective To construct an air health index (AHI) based on the exposure-response relationships of air pollution and ambient temperature with the years of life lost (YLL) in Tianjin. Methods The time series database of air pollution, meteorological factors, and non-accidental YLL from 2014-2019 in six urban areas of Tianjin were established. The data from 2014 to 2017 were used as the construction set to establish the exposure-response relationships of air pollution and ambient temperature with non-accidental YLL and establish the AHI model. The data from 2018 to 2019 were used as the validation set for verifying AHI. The generalized additive model (GAM) and weighted quantile sum (WQS) model were used to establish the exposure-response relationship between air pollution mixtures and non-accidental YLL. The distributed lag nonlinear model (DLNM) was fitted to assess the exposure-response relationship between ambient temperature and non-accidental YLL. Based on these obtained coefficients, the AHI and air quality health index (AQHI) were built. By comparing the associations between AHI, air quality health index (AQHI), and air quality index (AQI) with daily mortality and YLL and model goodness of fit to evaluate the validity of AHI. Results The formula for AHIt=EYLLt,air pollution+ambient temperature/475.11*10. The validation results showed that each IQR increase in AHI was associated with a higher increase in non-accidental mortality and YLL (10.61% and 353.37 person-year) compared with the corresponding values of AQHI and AQI. In addition, the model goodness of AHI was better than AQHI and AQI model. Conclusion Compared with AQHI and AQI, the AHI based on the integrating health effects of air pollution and ambient temperature has a better health risk prediction ability.

Associations of mobile phone use with male semen quality and sex hormones / 环境与职业医学

Background Experimental studies have shown that radiofrequency electromagnetic waves emitted by mobile phones can cause adverse effects on male reproductive health, including decreased semen quality and altered sex hormones. However, the results of epidemiological studies on the relationship between mobile phone use and male semen quality are inconsistent. Furthermore, there are few epidemiological studies on the association of mobile phone use with sex hormones. Objective To explore the associations of mobile phone use with male semen quality and sex hormones. Methods A total of 2045 men visited the reproductive medicine center of a hospital in Wuhan and ordered infertility examination were recruited from December 2018 to January 2020. Information on mobile phone use was obtained using a questionnaire. Among them, 1232 and 1694 men were eligible for semen quality analyses and sex hormone analyses, respectively. Multiple linear and logistic regression models were used to analyze the associations of mobile phone use with male semen quality and sex hormones. Results After adjusting for potential confounders, there was no statistically significant associations of mobile phone use with sperm progressive motility, sperm total motility, sperm concentration, sperm count, or serum luteinizing hormone (P>0.05). However, serum total testosterone showed a declined tendency with increasing daily duration of mobile phone use (Ptrend=0.08). Compared with men with daily mobile phone use of 0-2 h, men with daily mobile phone use of 2.1-5, 5.1-8, and >8 h showed decreased serum total testosterone concentrations by 6.29% (95%CI: 0.40%-11.84%), 6.01% (95%CI: 0.60%-12.19%), and 7.87% (95%CI: 0.40%-14.79%), respectively. Conclusion Mobile phone use is not associated with male semen quality and serum luteinizing hormone, but increasing daily duration of mobile phone use is potentially associated with a tendency to lower male serum total testosterone.

Association between wrist pain and awkward postures among workers in 10 key industries / 环境与职业医学

Background Prolonged awkward postures during occupational activities can lead to excessive musculoskeletal load on the wrist of workers and symptoms such as wrist pain or discomfort. Objective To survey the prevalence of wrist pain among workers in 10 key industries and analyze its correlation with wrist working postures. Methods By using stratified cluster sampling method, workers from 10 key industries, such as footwear manufacturing industry, shipbuilding manufacturing industry, and automobile manufacturing industry, were selected from seven regions in North China, East China, Central China, South China, Southwest China, Northwest China, and Northeast China. The demographic information, wrist working postures, pain in wrist of the workers were collected through a cross-sectional survey. Pearson χ2 test was used to compare prevalence by selected factors, trend χ2 test for between group comparison, and unconditional logistic regression models for the association of wrist working postures with wrist pain. Results There were 64052 workers enrolled in this survey, and 56286 provided valid questionnaires (the effective rate was 87.8%). According to the survey, the prevalence of wrist pain was 23.3% (13112/56286), and the industries with higher prevalences were footwear manufacturing (27.1%, 1927/7106), automobile manufacturing (24.9%, 5378/21560), and shipbuilding and related equipment manufacturing (24.4%, 850/3488) industries. Finger pinching (OR=2.09, 95%CI: 1.95-2.24), frequent wrist bending (OR=2.03, 95%CI: 1.92-2.15), fixed wrist bending (OR=1.77, 95%CI: 1.69-1.85), wrist on hard edge (OR=1.34, 95%CI: 1.28-1.40), and arms over shoulders (OR=1.11, 95%CI: 1.05-1.17) increased the risk of reporting wrist pain. Conclusion Awkward postures are related to wrist pain among workers in selected 10 key industries. The related factors are wrist on hard edge, frequent wrist bending, finger pinching, fixed wrist bending, and arms over shoulders.

Research progress of irradiation injuries anti-agents / 中华劳动卫生职业病杂志

Irradiation injuries anti-agents refer to drugs that can inhibit the initial stage of radiation injuries, or reduce the development of radiation injuries and promote the recovery of injuries when used early after irradiation exposure. According to the mechanism of action and the time of intervention, the irradiation injuries anti-agents are divided into four categories: radioprotectors, radiomitigators, radiation therapeutics for external radiation exposure, and anti-agents for internalized radionuclides. In this paper, the research progress of irradiation injuries anti-agents in recent years is reviewed.

Current status and research progress of occupational health monitoring in welding fume operations / 中华劳动卫生职业病杂志

Welding operations are widely present in the manufacturing production process, involving a large number of occupational groups, and are the key occupations where work injuries and occupational diseases occur in China. For different welding processes and welding materials, the content and focus of occupational health monitoring are different. At present, the item of occupational health examination in welding operation is in poor consistency with the on-site exposure of occupational hazard factors, and it is mainly concentrated in the stage of disease development, which can not reflect the early health damage caused by welding dust exposure in time. The emergence of biomarkers of welding dust can make up for this defect. Therefore, it is of great significance to describe the current situation of occupational health monitoring of welding dust and summarize the research progress of related biomarkers for the early prevention of diseases caused by welding dust and the practice of occupational health monitoring.

Detection rates of adenomas, advanced adenomas, and colorectal cancers among the opportunistic colonoscopy screening population: a single-center, retrospective study / 中华医学杂志(英文版)

BACKGROUND@#Colorectal cancer (CRC) screening is effective in reducing CRC incidence and mortality. The aim of this study was to retrospectively determine and compare the detection rate of adenomas, advanced adenomas (AAs) and CRCs, and the number needed to screen (NNS) of individuals in an average-risk Chinese population of different ages and genders.@*METHODS@#This was a retrospective study performed at the Institute of Health Management, Chinese People's Liberation Army General Hospital. Colonoscopy results were analyzed for 53,152 individuals finally enrolled from January 2013 to December 2019. The detection rate of adenomas, AAs, or CRCs was computed and the characteristics between men and women were compared using chi-squared test.@*RESULTS@#The average age was 48.8 years (standard deviation [SD], 8.5 years) for men and 50.0 years (SD, 9.0 years) for women, and the gender rate was 66.27% (35,226) vs . 33.73% (17,926). The detection rates of adenomas, AAs, serrated adenomas, and CRCs were 14.58% (7750), 3.09% (1641), 1.23% (653), and 0.59% (313), respectively. Men were statistically significantly associated with higher detection rates than women in adenomas (17.20% [6058/35,226], 95% confidence interval [CI] 16.74-17.53% vs . 9.44% [1692/17,926], 95% CI 8.94-9.79%, P  < 0.001), AAs (3.72% [1309], 95% CI 3.47-3.87% vs . 1.85% [332], 95% CI 1.61-2.00%, P  < 0.001), and serrated adenomas (1.56% [548], 95% CI 1.43-1.69% vs . 0.59% [105], 95% CI 0.47-0.70%, P  < 0.001). The detection rate of AAs in individuals aged 45 to 49 years was 3.17% (270/8510, 95% CI 2.80-3.55%) in men and 1.69% (69/4091, 95% CI 1.12-1.86%) in women, and their NNS was 31.55 (95% CI 28.17-35.71) in men and 67.11 (95% CI 53.76-89.29) in women. The NNS for AAs in men aged 45 to 49 years was close to that in women aged 65 to 69 years (29.07 [95% CI 21.05-46.73]).@*CONCLUSIONS@#The detection rates of adenomas, AAs, and serrated adenomas are high in the asymptomatic population undergoing a physical examination and are associated with gender and age. Our findings will provide important references for effective population-based CRC screening strategies in the future.

Effect of Home Blood Pressure Telemonitoring Plus Additional Support on Blood Pressure Control: A Randomized Clinical Trial / 生物医学与环境科学（英文）

OBJECTIVE@#Current clinical evidence on the effects of home blood pressure telemonitoring (HBPT) on improving blood pressure control comes entirely from developed countries. Thus, we performed this randomized controlled trial to evaluate whether HBPT plus support (patient education and clinician remote hypertension management) improves blood pressure control more than usual care (UC) in the Chinese population.@*METHODS@#This single-center, randomized controlled study was conducted in Beijing, China. Patients aged 30-75 years were eligible for enrolment if they had blood pressure [systolic (SBP) ≥ 140 mmHg and/or diastolic (DBP) ≥ 90 mmHg; or SBP ≥ 130 mmHg and/or DBP ≥ 80 mmHg with diabetes]. We recruited 190 patients randomized to either the HBPT or the UC groups for 12 weeks. The primary endpoints were blood pressure reduction and the proportion of patients achieving the target blood pressure.@*RESULTS@#Totally, 172 patients completed the study, the HBPT plus support group ( n = 84), and the UC group ( n = 88). Patients in the plus support group showed a greater reduction in mean ambulatory blood pressure than those in the UC group. The plus support group had a significantly higher proportion of patients who achieved the target blood pressure and maintained a dipper blood pressure pattern at the 12th week of follow-up. Additionally, the patients in the plus support group showed lower blood pressure variability and higher drug adherence than those in the UC group.@*CONCLUSION@#HBPT plus additional support results in greater blood pressure reduction, better blood pressure control, a higher proportion of dipper blood pressure patterns, lower blood pressure variability, and higher drug adherence than UC. The development of telemedicine may be the cornerstone of hypertension management in primary care.

Results of occupational health examination for gas station workers / 公共卫生与预防医学

Objective To understand the occupational health status of gas station workers, to analyze the characteristics of early health damage, and to provide a reference for the occupational health monitoring of workers in this industry. Methods The gas station workers who underwent occupational health examination in an occupational health examination institution in Tianjin in 2021were selected as the research subjects. The examination results were statistically analyzed. Results A total of 381 gas station workers were included in this study, with a sex ratio of male to female of 1.40:1. The top three tests with abnormal results from high to low were abdominal color Doppler ultrasound (39.63%), urine routine (29.13%), and blood pressure (23.62%). The detected fatty liver accounted for 74.83% of abnormal abdominal color Doppler ultrasound. Analysis of abnormal results of different genders showed that the detection rate of abnormal blood pressure, fatty liver and liver function in males was higher than that in females (χ2=16.40, 25.40, 15.98，P＜0.05), the detection rate of high GGT in males was significantly higher than that in females (χ2=16.04，P＜0.05）. The detection rate of abnormal urine routine in females was higher than that in males (χ2=12.85，P＜0.05), and the positive rate of urine white blood cells and blood in urine were significantly higher I women than those in men (χ2 =16.80, 11.66，P＜0.05). The abnormal detection rate of electrocardiogram of gas station workers increased with age (χ2=28.02，P＜0.05), and the abnormality of high blood pressure showed an increasing trend with age and working years（χ2=25.00, 15.26，P＜0.05). Conclusion The long-term exposure of gas station workers to chemical toxic substances such as organic solvents and benzene series and physical factors such as high temperature in summer and low temperature in winter will have a certain impact on health. It is suggested that employers should reasonably arrange their work systems and carry out occupational health monitoring in a targeted manner.

Advances in research on the health effects of occupational noise exposure / 公共卫生与预防医学

With the development of industrial production mechanization, the impact of occupational noise exposure on the body has attracted much attention. The impact of occupational noise on the body is not limited to the specific effects of hearing, but also includes non-specific effects on multiple systems such as nerves, cardiovascular, and reproductive systems. This paper expounds the health effects of occupational noise, and lays a theoretical foundation for relevant departments to prevent the health effects of occupational noise in the future.

Correlation between work fatigue and work-related musculoskeletal pain or injury in the occupational population in China / 中国职业医学

Objective: To analyze the current status of work-related musculoskeletal disorders (WMSDs), work fatigue and musculoskeletal pain in Chinese occupational population, and to study the relationship between work fatigue and musculoskeletal pain and WMSDs. Methods: A total of 66 961 employees from 323 enterprises in 15 key industries in China were selected as the study subjects using stratified cluster sampling method. The incidence of WMSDs in the past year was investigated using the Chinese version of the Musculoskeletal Disorders Questionnaire, and the work fatigue and musculoskeletal pain were investigated using Borg 6-20 Rating of Perceived Exertion Scale and visual analogue scale. The data were standardized using the age composition data of 18 to 60 years from the seventh national population census. Results: The standardized annual incidence of WMSDs was higher in the front-line workers than that in the administrative and other supportive staff (38.82% vs 36.30%). The detection rates of work fatigue and musculoskeletal pain in the study subjects were 44.54% and 63.08%, respectively. The result of S-curve fitting showed that the risk of WMSDs increased with the level of work fatigue (P<0.01). Among the front-line workers, the average of monthly fatigue frequency in the neck, shoulder, lower back, upper back, wrist/hand, foot and ankle, knee, leg, and elbow were higher in the group with WMSDs compared to those without WMSDs (all P<0.01). The pain degree of musculoskeletal pain was higher in all nine sites in the fatigued group than in the no-fatigue group (all P<0.01). The standardized detection rate of musculoskeletal pain was higher in the fatigued group than in the non-fatigued group (80.38% vs 25.71%). The work fatigue was moderate and positively correlated with musculoskeletal pain in all seven sites except the lower back and elbow, with Kendall Tau-b correlation coefficients ranging from 0.423 to 0.546 (all P<0.01). Conclusion: There is a good correlation between work fatigue and local musculoskeletal pain, work fatigue and WMSDs in Chinese occupational population. Implementing ergonomic interventions to control the development of work fatigue can be an effective measure for preventing WMSDs.

Combining neutrophil-lymphocyte ratio and platelet-lymphocyte ratio predicted the prognosis of hepatocellular carcinoma patients after liver transplantation / 中华器官移植杂志

Objective:To explore the prognostic values of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio(PLR)and NLR-PLR score for carcinoma(HCC)patients undergoing liver transplantation(LT).Methods:From July 2015 to October 2021, clinical data are retrospectively reviewed for 110 HCC patients undergoing orthotopic LT at Third Hospital of Hebei Medical University.The values of NLR and PLR were calculated.And the cut-off values of NLR and PLR were obtained by receiver operating characteristic (ROC) curve and then grouped according to the cut-off values.Survival time is analyzed by Kaplan-Meier method and Log-rank test performed for inter-group comparison.Univariate and multivariate analyses are performed based on Cox proportional risk regression model.NLR <3.37 and PLR <105.96 are denoted as 0 point while NLR ≥3.37 and PLR ≥105.96 as 1 point.Two points are added up as NLR-PLR score.According to NLR-PLR score, they are divided into 3 groups of 0, 1 and 2.Results:Median overall survival(OS)is 27 months in patients with NLR-PLR score 0, 26.5 months in patients with NLR-PLR score 1 and 6 months in patients with NLR-PLR score 2.Median OS in patients with NLR-PLR score 2 is significantly shorter than that in those with NLR-PLR score 0/1.And the difference is statistically significant( P<0.001).Median disease-free survival(DFS)is 24.5 months in NLR-PLR 0 group, 24 months in NLR-PLR 1 group and 6 months in NLR-PLR 2 group.The difference is statistically significant( P=0.002).Univariate analysis show that Child-Pugh grade, MELD score, NLR/PLR level, NLR-PLR score, complying with University of California San Francisco Criteria(UCSF)criteria and absence/presence of microvascular invasion(MVI)have an impact on patient survival.Further multivariate analysis show that NLR-PLR score, complying with UCSF criteria and MELD score are independent risk factors affecting patients' prognosis and survival. Conclusions:NLR, PLR and NLR-PLR score may predict long-term survival of patients.And NLR-PLR score is an independent risk factor for patient survival.It has more predictive value than NLR/PLR.

Awareness of diabetes knowledge and its influencing factors among health examination population / 中华健康管理学杂志

Objective:To investigate the awareness of diabetes knowledge among the health examination population and its influencing factors.Methods:A cross-sectional study. From september to november 2022, the subjects of six health examination centers located in six different cities (Beijing, Shanghai, Tianjin, Chongqing, Xiamen, Hangzhou) in China were investigated in the form of questionnaires to investigate the awareness of diabetes core information and the level of trust to different information sources of diabetes knowledge. According to the questionnaire results, the subjects were divided into a high awareness group of diabetes core information and a low awareness group. Logistic regression was used to analyze the influencing factors of diabetes core information awareness; the t-test was used to compare the trust degree of the two groups to different information sources. Results:A total of 9 315 people were included in the six centers, including 4 932 men (52.90%) with an average age of (39.36±12.64) years and 4 383 women (47.10%) with a mean age of (37.47±11.85) years. Only 36% of the people had high awareness of diabetes core information; variables such as gender, age, education level, physical examination frequency in the past three years, package price of this physical examination, self-evaluation of diabetes knowledge, diabetes status, and city of residence were variables that affect the level of awareness of core information related to diabetes (all P<0.05). Compared with the low awareness group of diabetes core information, the high awareness group trusted professional medical staff ( t=-9.597, P<0.05) and community health promotion more ( t=-5.014, P<0.05), but did not trust the emerging popular science propaganda means, such as WeChat official accounts/WeChat groups/QQ groups, Internet web page, Tiktok/Kwai and other short video APPs. Conclusion:The awareness rate of diabetes knowledge among the health examination population is low, and it is affected by many factors; Health education on diabetes knowledge should be carried out for people undergoing physical examination.

Development trend of physical examination volume and revenue in health-checkup institutions in China from 2010 to 2019 / 中华健康管理学杂志

Objective:To investigate the development trend of physical examination volume and revenue in health-checkup institutions in China from 2010 to 2019.Methods:In this longitudinal study, the annual income, annual physical examination volume and other indicators reflecting institutional size were collected with questionnaire from 374 health-checkup institutions in the year of 2010, 2015 and 2019. The geometric mean method is used to calculate the compound annual growth rate (CAGR) of the annual physical examination volume, annual income, mean per capita cost from 2010 to 2015 and 2015 to 2019.Results:The annual physical examination volume of health-checkup institutions increased from 1.81 (1.00, 3.20) ×10 4 person times in 2010 to 5.08(3.50, 7.28)×10 4 person times in 2019; the CAGR of the physical examination volume from 2010 to 2015 was 14.04%(8.14%, 23.78%), and it was 9.49%(3.39%, 19.07%) from 2015 to 2019. The annual revenue increased from 768.73 (350.00, 1 623.75) ×10 4 yuan in 2010 to 3 500.00 (1 997.73, 6 818.54) ×10 4 yuan in 2019; the CAGR of annual revenue from 2010 to 2015 was 25.75% (15.17%, 35.09%), and it was 15.67% (8.78%, 26.11%) from 2015 to 2019. The mean per capita cost increased from 434.26 (278.82, 666.66) yuan in 2010 to 755.80 (506.90, 1 005.42) yuan in 2019; the CAGR of the mean per capita cost was 9.82% (1.71%, 17.10%) from 2010 to 2015, and it was 5.37% (0.95%, 10.46%) from 2015 to 2019. Conclusion:From 2010 to 2019, health-checkup institutions in China developed rapidly, and the CAGR of the annual physical examination volume, annual revenue, mean per capita cost are high.

Particular consideration on radiation shielding of a CyberKnife room / 中华放射医学与防护杂志

Objective:To verify radiation shielding effect of the maze of the CyberKnife room, so as to identify and correct the deficiencies in the shielding designs in certain circumstances.Methods:In line with the radiation protection shielding design scheme of the CyberKnife room provided by the producer, the consideradtions are focused on the useful beam that could mainly pass through the image center, but not the outer wall of the maze. However, during the inspection and acceptance of radiological protection in the built room, it was found that in a certain situations useful wire did not pass through the imaging center. Therefore, the additional shielding and protection facilities were built and verified.Results:After verification and acceptance on the scene, in the case where the useful beam was passing through the image center, the highest ambient dose equivalent rate at the concerned points 30 cm away from the outer wall of the maze was 0.31 μSv/h, less than the control level 10 μSv/h. In the opposite case, the highest ambient dose equivalent rate at the same points as above was 301.67 μSv/h, ablut 30 times as much as the control level. After the thickness in maze outer wall was enhanced, the highest ambient dose equivalent rate at the same as above was 2.14 μSv/h. This testing result met the concerned national standard.Conclusions:It is desirable that in designing the outer wall shielding in the maze in a CyberKnife room, attention should be paid to whether or not the useful beam could pass through the image center, or otherwise directly irradiate on the maze on the basis of the movement range of the accelerator. Shielding wall thickness should be calculated on the basis of the irradiation ragne and the distance between source location and the concerned points to ensure being in compliance with the requirements of the concerned national standard. Meanwhile, it should protect the workers occupying at the concerned locations from receiving higher radiation doses.

Establishment of air quality health index based on cumulative health risk of air pollution in Tianjin / 环境与职业医学

Background Cumulative risk index (CRI), as a commonly used approach to estimate the joint effects of multiple air pollutants on health, has been used by few studies to construct an air quality health index (AQHI). Objective To construct an AQHI based on the CRI of air pollution in Tianjin and evaluate the validity of the AQHI. Methods Daily data on air pollutants, meteorological factors, and non-accidental deaths during 2015–2019 in Tianjin were collected to create a time-series object. Descriptive statistical analyses were used to describe the characteristics of the data. To determine the best lag day and indicative pollutant, single-pollutant and two-pollutant generalized additive models were fitted to construct the exposure-response relationships between air pollutants and non-accidental deaths. After that we evaluated a CRI of air pollution using multi-pollutant models and constructed an AQHI and its classifications based on the CRI. Finally, we compared the exposure-response associations and coefficients of the AQHI and the conventional air quality index (AQI) with non-accidental deaths, and evaluated the health risk communication validity of the AQHI using generalized cross validation (GCV) values and R2 values. Results We selected lag1 as the best lag day and PM2.5, SO2, NO2 and O3 as the appropriate pollutants according to the unqualified rates of pollutants and significant statistical results. One μg·m−3 increase of PM2.5, SO2, NO2, and O3 was associated with −0.00002, 0.00079, 0.00015, and 0.00042 increase in effect size b of the non-accidental mortality, respectively. Based on these coefficients, we calculated the CRI and AQHI. According to a pre-determined classification scheme of the AQHI, the air quality of 63% study days was low risks and that of 34% study days was median risks. The associations of AQHI and AQI with non-accidental deaths in different populations were evaluated. The results showed that the excess risks of non-accidental deaths in total, female, and male populations for per interquartile range (IQR) increase in AQHI were higher than the corresponding values of AQI. The GCV values of the AQHI model (2.694, 1.819, and 1.938, respectively) were lower than those of the AQI model (2.747, 1.850, and 1.961, respectively), and the R2 values of the AQHI model (0.849, 0.780, and 0.820, respectively) were higher than those of the AQI model (0.846, 0.776, and 0.817, respectively). Conclusion Compared with AQI, the CRI-based AQHI may communicate the air pollution-related health risk to the public more effectively in Tianjin.

Effects of exposure to disinfection byproducts on fetal growth and development: Research progress and perspectives / 环境与职业医学

Disinfection byproducts (DBPs) are a new class of contaminants that are formed during the process of drinking water disinfection in waterworks. To date, more than 700 DBPs have been identified in drinking water, many of which have been found to be potentially cytotoxic, genotoxic, carcinogenic, or teratogenic. As a class of ubiquitous contaminants with highly potential health hazards in drinking water, the reproductive and developmental toxicity of DBPs has been a public concern. This paper reviewed the research progress on the effects of exposure to DBPs on fetal growth and development and also proposed perspectives for future directions. This work aimed to provide reference for health risk assessment and standard establishment of DBPs in drinking water.