Search

Background: Despite increasing awareness, silica dust-induced silicosis still contributes to the huge disease burden in China. Worryingly, recent silica dust exposure levels and silicosis risk in Chinese noncoal mines remain unclear., Objective: We aimed to determine recent silica dust exposure levels and assess the risk of silicosis in Chinese noncoal mines., Methods: Between May and December 2020, we conducted a retrospective cohort study on 3 noncoal mines and 1 public hospital to establish, using multivariable Cox regression analyses, prediction formulas of the silicosis cumulative hazard ratio (H) and incidence (I) and a cross-sectional study on 155 noncoal mines in 10 Chinese provinces to determine the prevalence of silica dust exposure (PDE), free silica content, and total dust and respirable dust concentrations. The qualitative risk of silicosis was assessed using the International Mining and Metals Commission's risk-rating table and the occupational hazard risk index; the quantitative risk was assessed using prediction formulas., Results: Kaplan-Meier survival analysis revealed significant differences in the silicosis probability between silica dust-exposed male and female miners (log-rank test χ21=7.52, P=.01). A total of 126 noncoal mines, with 29,835 miners and 4623 dust samples, were included; 13,037 (43.7%) miners were exposed to silica dust, of which 12,952 (99.3%) were male. The median PDE, free silica content, total dust concentration, and respirable dust concentration were 61.6%, 27.6%, 1.30 mg/m3, and 0.58 mg/m3, respectively, indicating that miners in nonmetal, nonferrous metal, small, and open-pit mines suffer high-level exposure to silica dust. Comprehensive qualitative risk assessment showed noncoal miners had a medium risk of silicosis, and the risks caused by total silica dust and respirable silica dust exposure were high and medium, respectively. When predicting H and I over the next 10, 20, and 30 years, we assumed that the miner gender was male. Under exposure to current total silica dust concentrations, median I10, I20, and I30 would be 6.8%, 25.1%, and 49.9%, respectively. Under exposure to current respirable silica dust concentrations, median I10, I20, and I30 would be 6.8%, 27.7%, and 57.4%, respectively. These findings showed that miners in nonmetal, nonferrous metal, small, and open-pit mines have a higher I and higher qualitative silicosis risk., Conclusions: Chinese noncoal miners, especially those in nonmetal, nonferrous metal, small, and open-pit mines, still suffer high-level exposure to silica dust and a medium-level risk of silicosis. Data of both total silica dust and respirable silica dust are vital for occupational health risk assessment in order to devise effective control measures to reduce noncoal mine silica dust levels, improve miners' working environment, and reduce the risk of silicosis., (©Kai Liu, Xin Sun, Wei-Jiang Hu, Liang-Ying Mei, Heng-Dong Zhang, Shi-Biao Su, Kang Ning, Yun-Feng Nie, Le-Ping Qiu, Ying Xia, Lei Han, Qiang Zhi, Chun-Bo Shi, Geng Wang, Wei Wen, Jian-Qiong Gao, Bing Yu, Xin Wang, Yi-Wen Dong, Ning Kang, Feng Han, Hong-Ying Bian, Yong-Qing Chen, Meng Ye. Originally published in JMIR Public Health and Surveillance (https://publichealth.jmir.org), 02.09.2024.)

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.

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.

Objective: To explore the noise exposure level and the health status of workers in transportation equipment manufacturing industry, and provide a scientific basis for guidance and implementation of intervention measures. Methods: From January to December in 2019, a total of 2088 noise workers from a large enterprise were selected by cluster sampling method in railway transportation equipment manufacturing, automobile manufacturing and aerospace aircraft manufacturing enterprises. The worker's noise exposure level was detected. Occupational health checkups were performed on the noise workers including electrical audiometry, blood pressure and electrocardiogram. χ(2) test and trend χ(2) test were used to analyze the data. Results: The noise exposure level of 66.9% (1396/2088) workers exceeded 85 dB (A) , and the median noise level was 87.9 (84.3-90.3) dB (A) . Among them, workers of railway transportation equipment manufacturing enterprises had the highest noise exposure level[89.9 (87.8-91.6) dB (A) ]. The detection rate of high-frequency hearing loss, abnormal blood pressure and abnormal electrocardiogram of noise workers were 15.7% (327/2088) , 18.1% (378/2088) and 6.1% (128/2088) , respectively. The differences in the detection rates of high-frequency hearing loss, abnormal blood pressure, and abnormal electrocardiogram in workers of railway transportation equipment manufacturing enterprises, automobile manufacturing enterprises, and aerospace manufacturing enterprises were statistically significant ( P <0.05) . Workers of railway transportation equipment manufacturing enterprises had higher detection rates of high-frequency hearing loss (17.6%, 186/1056) . Workers of aerospace manufacturing enterprises had higher detection rates of abnormal blood pressure and abnormal electrocardiogram (26.3%, 169/642; 10.0%, 64/642) . The differences in the detection rates of high-frequency hearing loss, abnormal blood pressure and abnormal electrocardiogram of noise workers were statistically significant in different age and working age groups, and gradually increased with age and working age ( P <0.05) . The difference in the detection rate of high-frequency hearing loss of noise workers was statistically significant in different noise intensity groups, and the overall trend was increasing ( P <0.05) . Conclusion: The transportation equipment manufacturing industry has serious noise hazards, especially the railway transportation equipment manufacturing industry. Long-term occupational noise exposure can adversely affect workers' hearing and cardiovascular system. Enterprises should strengthen occupational health inspections, and at the same time, take personal protective measures to protect the health of workers.

Objective: To investigate the characteristics of asymmetric hearing loss in automobile manufacturing workers and the effect of occupational noise exposure on asymmetric hearing loss. Methods: A cross-sectional approach was used in this study. From March 2017 to February 2018, Subjects (7066) from four complete vehicle factories were given a pure tone audiometry (Hearing thresholds were measured at frequencies of 0.5, 1, 2, 3, 4 and 6 kHz in each ear) and were required to complete a health-related information questionnaire. According to the inclusion criteria, a total of 6339 workers were selected. The mean hearing thresholds for the left and right ears at overall frequencies were compared using the repeated means analysis of variance (ANOVA) test. The threshold differences at each frequency were compared using paired t tests. Results: The overall mean left minus right threshold difference across all frequencies was determined to be 0.58 dB, which met statistical significance ( P <0.01) . Hearing threshold in the left ear was statistically significantly higher compared with the right ear at each frequency. The differences between binaural threshold shifts at each frequency among subjects with a asymmetry in terms of worse left ear and worse right ear were at the range of 6.17-9.87 dB and 6.39-10.92 dB, respectively. Hearing threshold in the left ear was statistically significantly higher compared with the right ear at only 2, 3 kHz of subjects with high-frequency hearing threshold shifts (HFHTs) more than 25 dB. Hearing threshold in the left ear was statistically significantly higher compared with the right ear at only 3 kHz of subjects with high-frequency hearing threshold shifts (HFHTs) more than 30 dB. With the increase of HFHTs, the proportion of subjects with a asymmetry at 2 and 3 kHz of more than 10 dB in terms of worse left ear and worse right ear increased. Conclusion: The average hearing threshold of the left ear across overall frequencies is higher compared with the right ear, the proportion of the cases with a higher left ear hearing threshold is higher that that of the cases with a higher right ear hearing threshold. As hearing loss caused by occupational noise exposure getting worse, the proportion of the cases with a higher left ear hearing threshold and the cases with a higher right ear hearing threshold may tent to be the same.

Objective: ICMM occupational health risk assessment model was be used to evaluate the risk of a lead-acid battery enterprise. Methods: In November 2016, a lead-acid battery company in Jiangsu Province was selected as the research object. Based on the occupational health survey data and occupational hazard assessment reports, the ICMM risk assessment model was used to conduct occupational health risks in eight key positions of a lead-acid battery enterprise. The risk assessment results was verified by actual test results. Results: In the quantitative assessment model, the occupational health risk assessment results for the castings and welding positions exposed to lead smoke, and the occupational health risk assessment results for the grinding and dividing positions exposed to lead dust existed unacceptable risks. The occupational health risk assessment results for the ball-milled and plated positions exposed to lead dust existed tolerable risks. The occupational health risk assessment results for the lead-plated and soldered positions exposed to sulphuric acid pastes and acids existed potential risks. In qualitative evaluation matrix method, the occupational health risk assessment results for the castings and welding positions exposed to lead smoke, and the occupational health risk assessment results for the grinding and dividing positions exposed to lead dust existed high risks, the occupational health risk assessment results for other four key positions were considered to be with low risks. Conclusion: The key control points for lead smoke in this enterprise were castings and welding positions; The key control points for lead dust were the grinding and separating brush positions. The quantitative assessment model and the qualitative assessment matrix method in the ICMM model were consistent with the actual test results in the eight health risk assessments of occupational hazards in key positions. Therefore, the method could be applied to the assessment of occupational health risks of the lead-acid battery enterprise. According to the results of the assessment, improvements could be made to high-risk positions and the concentration of occupational hazards in high-risk posts could be reduced to better protect the health of workers.