BACKGROUND: Owing to shortage of surgical and N95 filtering facepiece respirators (FFRs) during the COVID-2019 pandemic, various masks were developed to prevent infection. This study aimed to examine the inward leakage rate (ILR) of sealed face masks and modified surgical masks using a quantitative fit test and compared it with the ILR of unmodified N95 FFRs. METHODS: We conducted paired comparisons of ILRs of bent nose-fit wire masks, double masks, and N95 FFRs from October to December 2021. To measure the protective effectiveness of masks, participants wore masks, and the number of particles outside and inside the mask were measured. The ILR was based on the percentage of particles entering the mask using a fit tester. RESULTS: We enrolled 54 participants (20 men and 34 women) in this study. The median ILR for surgical masks without and with a W-shaped bend in the nose-fit wire were 96.44% and 50.82%, respectively. The nose-fit wire adjustment reduced the ILR of surgical masks by a mean of 28.57%, which was significantly lower than the ILR without adjustment (P < 0.001). For double masks, with surgical or polyurethane masks on top of the W-shaped mask, the ILR did not differ significantly from that of N95. Although the filtration performance of double surgical masks matched that of N95 masks, their ILR was notably higher, indicating that double masks do not provide equivalent protection. CONCLUSIONS Wearing N95 masks alone is effective in many cases. However, surgical mask modifications do not guarantee consistent effectiveness. Properly selected, sealed masks with a good fit overcome leakage, emphasizing their crucial role. Without evidence, mask-wearing may lead to unexpected infections. Education based on quantitative data is crucial for preventing adverse outcomes.
Male ; Humans ; Female ; N95 Respirators ; COVID-19/epidemiology* ; Masks ; Pandemics/prevention & control* ; Respiratory Protective Devices ; Materials Testing ; Equipment Design ; Occupational Exposure/prevention & control*

Humans ; Nutrition Assessment ; Prognosis ; Silicosis/prevention & control* ; Occupational Diseases ; China/epidemiology* ; Occupational Exposure ; Silicon Dioxide

Humans ; Coal ; Dust/analysis* ; Anthracosis ; China/epidemiology* ; Coal Mining ; Occupational Exposure

OBJECTIVE: The study aimed to estimate the benchmark dose (BMD) of coke oven emissions (COEs) exposure based on mitochondrial damage with the mitochondrial DNA copy number (mtDNAcn) as a biomarker. METHODS: A total of 782 subjects were recruited, including 238 controls and 544 exposed workers. The mtDNAcn of peripheral leukocytes was detected through the real-time fluorescence-based quantitative polymerase chain reaction. Three BMD approaches were used to calculate the BMD of COEs exposure based on the mitochondrial damage and its 95% confidence lower limit (BMDL). RESULTS: The mtDNAcn of the exposure group was lower than that of the control group (0.60 ± 0.29 vs. 1.03 ± 0.31; P < 0.001). A dose-response relationship was shown between the mtDNAcn damage and COEs. Using the Benchmark Dose Software, the occupational exposure limits (OELs) for COEs exposure in males was 0.00190 mg/m ³. The OELs for COEs exposure using the BBMD were 0.00170 mg/m ³ for the total population, 0.00158 mg/m ³ for males, and 0.00174 mg/m ³ for females. In possible risk obtained from animal studies (PROAST), the OELs of the total population, males, and females were 0.00184, 0.00178, and 0.00192 mg/m ³, respectively. CONCLUSION Based on our conservative estimate, the BMDL of mitochondrial damage caused by COEs is 0.002 mg/m ³. This value will provide a benchmark for determining possible OELs.
Male ; Female ; Animals ; Coke ; Polycyclic Aromatic Hydrocarbons ; DNA Copy Number Variations ; Benchmarking ; Occupational Exposure/analysis* ; DNA, Mitochondrial/genetics* ; DNA Damage

Humans ; Occupational Diseases/epidemiology* ; Occupational Health ; China/epidemiology* ; Occupational Exposure

Objective: To analyze the status of prevention and treatment of occupational diseases among mining and manufacturing industries in China in 2019, provide the scientific basis for the formulation and revision of policies and standards of prevention and treatment of occupational diseases. Methods: In May 2022, Collecting data of a project named Surveillance of Occupational Hazards in the Workplace in 2019 through the National Surveillance System for Occupational Hazards in the workplace. Compare the status of prevention and treatment of occupational diseases in 63 563 enterprises of mining and manufacturing industries among different dimensions. Results: The training rate of managers was 76.17% and that of occupational health managers was 76.97%. The rate of reporting of occupational diseases hazardous items was 67.58%, the rate of launching of the detection of occupational hazards was 57.16%, and the rate of launching of occupational health examination was 62.42%. Excluding the distribution rate of dust mask, the installation rate of various occupational prevention facilities and the distribution rate of gas mask and hearing protector were less than 80%. The differences in all the indicators among different areas, enterprise scales, economic types were statistically significant (P<0.05) . Conclusion: There are still some enterprises which are relatively weak in the ability of the prevention and treatment of occupational diseases in China. Measures such as special support, guidance and strengthen supervision should be taken towards those enterprises toimprove the awareness of prevention and treatment of occupational diseases and the level of that.
Humans ; Occupational Exposure ; Occupational Diseases/prevention & control* ; Manufacturing Industry ; Workplace ; China/epidemiology* ; Occupational Health

Objective: To understand the exposure level of dust and noise in the mining industry and provide data support for revising policy for the prevention and control of occupational diseases. Methods: In May 2022, Data was collected through the National Surveillance Program for Occupational Hazards in the Workplace. Descriptive analysis was conducted for dust and noise levels by industry type and enterprise size from 7, 679 enterprises in the mining industry among 29 provincial regions nationwide. Results: The enterprises in the mining industry included in the National Surveillance Program for Occupational Hazards in the Workplace are mainly small and micro, accounting for 47.97% (3684/7679) and 30.00% (230/7679) respectively. The industry is mainly compred of employers in the non-metallic ming and beneficiation industry, accounting for 50.25% (3859/7679). Among the enterprises with silica dust, coal dust, and noise hazards, the proportion of enterprises where total dust concentration and noise intensity exceed the standard is higher than 50%. 30% of the posts are with an exposure level of silica dust, coal dust, and noise that exceeds the standard. The exceedance rate and the median of the time-weighted average concentration of total coal dust among large and medium-sized enterprises are higher than those among small and micro-sized enterprises (P<0.05) . Conclusion: The dust and noise hazards in the mining industry are lower than in the past in China, but more than 25% of workers are still at a high risk of occupational pneumoconiosis and noise deafness. Therefore, intervention and surveillance strategies should be strengthened in the future.
Humans ; Dust/analysis* ; Occupational Exposure/analysis* ; Occupational Health ; Coal ; Silicon Dioxide/analysis* ; Coal Mining

Objective: To analyze the case characteristics of Chronic obstructive pulmonary disease caused by occupational irritant chemicals (OI-COPD). To provide basis for revising its diagnostic criteria. Methods: From June to December 2021, we investigated the information of OI-COPD patients confirmed by Shandong Institute of Occupational Health and Prevention of Occupational Diseases, Guangxi Zhuang Autonomous Region Institute of Occupational Disease Prevention and Control, Qingdao Central Hospital affiliated to Qingdao University and other diagnostic institutions in the past five years, a total of 41 cases. The basic information of OI-COPD cases, occupational risk factors exposure information, medical history, smoking history and clinical symptoms were analyzed retrospectively. The measurement data were tested for normal distribution, which was described by x±s, and compared between groups by t test; Those who do not conform to the normal distribution are described by the median [M (Q(1), Q(3)) ] and analyzed by nonparametric test; The counting data were expressed in frequency and rate (% ), and the comparison between groups was tested. Results: Of the 41 cases, 33 were male and 8 were female. The age of the patient diagnosed with OI-COPD was (49.5±10.3) years old, and the minimum age was 30 years old; Among them, 8 patients had a definite long-term smoking history (more than 5 years) ; The exposure duration of occupational risk factors was (18.6±10.3) years, of which 3 patients had exposure duration of less than 5 years; The occupational risk factors leading to OI-COPD include acids and acid-forming compounds, bases, aldehydes, nitrogen oxides, chlorine and its compounds, etc. The exposure level of occupational risk factors is related to the degree of COPD airflow restriction (χ(2)=6.17, P <0.05). 18 patients with diagnosis age <50 years old were diagnosed as early-onset COPD. The incidence of respiratory symptoms in the early diagnosis COPD group was lower than that in the non-early diagnosis COPD group, and the FEV1% pred was significantly higher than that in the non-early diagnosis COPD group. The difference was statistically significant (P<0.01 ) . Conclusion: The exposure level of occupational risk factors may be the risk factor affecting the degree of COPD airflow restriction. With the increase of the exposure level of COPD patients, the proportion of respiratory symptoms will also increase accordingly.
Humans ; Male ; Female ; Adult ; Middle Aged ; Retrospective Studies ; China/epidemiology* ; Pulmonary Disease, Chronic Obstructive/diagnosis* ; Lung ; Risk Factors ; Occupational Diseases/diagnosis* ; Occupational Exposure/adverse effects*

Occupational disease hazards in plywood manufacturing mainly include wood dust, formaldehyde, phenol, ammonia, noise, terpene, microorganisms, etc. The exposure is complex with multiple factors accompanied or coexisted. In the production process, these factors are exceeded, and mass occupational disease hazard events occurred among workers. Exposure to wood dust, formaldehyde, terpene, etc., put workers at increased risk of cancer. This article provides a review of this issue in order to provide a scientific basis for the prevention and control of occupational disease hazards in plywood manufacturing.
Humans ; Wood/chemistry* ; Occupational Diseases/chemically induced* ; Formaldehyde/adverse effects* ; Terpenes ; Dust ; Occupational Exposure/adverse effects*

Objective: To analyze the concentrations of glyphosate and its metabolites in occupational exposed workers and their possible effects on human health, so as to provide a reference for improving the safe use of glyphosate and toxicity research. Methods: From April to December 2020, 247 workers directly exposed to glyphosate in 5 enterprises were selected as the contact group, and 237 workers who were not exposed to glyphosate and other pesticides in the same enterprise were selected as the control group. Questionnaire survey and occupational health examination were conducted on objects, and the concentrations of glyphosate and its metabolites in the air of workplaces and biological samples were detected. The correlation between the concentrations and the difference of health examination between the two groups were analyzed. Results: The urine glyphosate concentration (0.022-47.668 mg/L), the rate of exceeding the standard (60.32%, 149/247) and the urine aminomethyl phosphonic acid concentration (<0.010-1.624 mg/L) in the contact group were higher than those in the control group [urine glyphosate concentration (<0.020-4.482 mg/L), the rate of exceeding the standard (2.53%, 6/237) and the urine aminomethyl phosphonic acid concentration (<0.010-0.524 mg/L) ], respectively (P<0.001). The exceeding standard rate of glyphosate concentration in the workplace was 33.67% (33/98). The concentration of glyphosate in the workplace was positively correlated with the concentrations of glyphosate and aminomethylphosphonic acid in urine (r(s)=0.804, 0.238, P<0.001), and the concentration of glyphosate in urine was positively correlated with the concentration of aminomethylphosphonic acid in urine (r(s)=0.549, P<0.001). The alanine aminotransferase (ALT), white cell ratio, creatinine, uric acid, the abnormal rates of ALT and total protein (TP) in the contact group were higher than those in the control group, and TP was lower than that in the control group, the differences were statistically different (P<0.05). The abnormal rates of overall liver function, overall renal function, blood routine test, urine routine test, electrocardiogram, liver B ultrasound and blood lipid in the contact group were significantly higher than those in the control group (P<0.05) . Conclusion: The concentration of glyphosate in the workplace is related to the concentrations of glyphosate and aminomethyl phosphonic acid in the urine of workers, and exposure to glyphosate may have some harmful effects on human health.
Humans ; Occupational Exposure/adverse effects* ; Health Status