[Investigation of serum surface active protein D and clara cell protein levels in workers exposed to silica dust in ferrous metal foundry].

Objective: To investigate the levels of serum surface active protein D (SP-D) and clara cell protein (CCl6) in workers exposed to black silica dust, and analyze its influencing factors. Methods: From July to September 2021, 174 workers in 37 positions exposed to silica dust in 5 ferrous metal foundry were investigated by cross-sectional research method. The exposure concentration of silica dust workers was obtained through occupational health field investigation and detection, and the general situation of the study subjects was obtained through questionnaire survey and peripheral blood was collected. Double antigen sandwich enzyme-linked immunosorbent assay (ELISA) was used to detect the concentrations of SP-D and CC16 in serum of workers. The mean values were compared by one-way ANOVA, and the influencing factors of SP-D and CC16 concentrations in serum were analyzed by ordered multiple logistic regression. Results: The time-weighted average concentration (C-TWA) of 174 workers exposed to silica dust (respirable dust) ranged from 0.09 mg/m(3)~3.58 mg/m(3), and the C-TWA overstandard rate of dust exposed workers was 32.18% (56/174) , with differences among workers in different positions (χ(2)=28.85, P<0.001) . The highest concentration of silica dust was (0.82±0.11) mg/m(3). Using C-TWA<50% OEL occupational exposure limit (OEL) as reference, serum SP-D concentration in workers with ≥50% OEL was increased (OR=4.95, 95%CI: 1.86~13.17, P=0.001) , while CC16 concentration was decreased (OR=0.15, 95%CI: 0.05~0.40, P<0.001) ; Serum CC16 concentration decreased in workers exposed to silica dust C-TWA≥OEL (OR=0.46, 95%CI: 0.28~0.98, P=0.043) . Compared with those with low occupational health literacy, the serum SP-D concentration of workers with high occupational health literacy decreased (OR=0.48, 95%CI: 0.25~0.92, P=0.027) and CC16 concentration increased (OR=2.09, 95%CI: 1.10-3.97, P=0.024) . Conclusion: When no abnormality was found in the physical examination of workers, the serum SP-D and CC16 concentration levels changed, and the change was related to the concentration of workers exposed to silica dust.

[Analysis of dust hazard characteristics in 59 ferrous metal foundry enterprises in Ningbo City].

Objective: To analyze the post distribution of dust concentration in ferrous metal foundry enterprises and evaluate the occupational health risks, and provide basis for policies of the formulation of pneumoconiosis prevention and control. Methods: From August to September in 2020, the basic information, dust hazard information and occupational health management information of 59 ferrous metal casting enterprises were investigated, the dust concentration distribution was analyzed, and the risk assessment was carried out by using the quantitative assignment model. The dust concentration is tested by LSD method after logarithmic treatment. The 3 times time weighted average allowable exposure concentration of dust is taken as the peak concentration limit of dust; The time weighted average allowable exposure concentration of dust converted by exposure time is taken as the time weighted average exposure concentration limit of dust, and whether the time weighted average exposure concentration and peak concentration of dust at the same post exceed the limit is taken as the basis for exceeding the limit of dust post concentration to calculate the post exceeding the limit rate. Results: The dust hazards were mainly distributed in the posts of sand treatment, molding, sand falling, sand cleaning and cutting and grinding. Dust exposure time weighted average concentration was 0.44 (0.03, 5.11) mg/m(3), peak exposure concentration was 1.30 (0.18, 10.94) mg/m(3), and the over standard rate of Posts was 38.92% (79/203) . Weighted average exposure concentration of other dust (total dust) in the cutting and grinding post is 1.50 (0.15, 7.40) mg/m(3), peak exposure concentration is 0.90 (0.07, 12.48) mg/m(3), and the post exceedance rate is 4.88% (2/41) . Weighted average exposure concentration of silica dust (exhaling dust) in dust operation posts of investment casting enterprises is 0.43 (0.05, 6.35) mg/m(3), peak exposure concentration is 0.90 (0.12, 8.28) mg/m(3), and the post over standard rate is 35.77% (49/137) ; Weighted average exposure concentration of other dust (total dust) at the cutting and grinding post is 2.00 (11.00, 21.00) mg/m(3), and the post exceedance rate is 2.50% (2/80) . There was no significant difference in the concentration of respirable dust between sand casting and investment casting (P>0.05) . The concentration of respirable dust in sand casting was higher than that in sand treatment, molding and sand cleaning posts (P<0.05) . The concentration of silica dust in investment casting was higher than that in sand treatment and molding posts, and that in sand cleaning posts was higher than that in sand treatment posts (P<0.05) . 98.48% (454/461) of the dust operation posts have an occupational health risk value greater than or equal to 400, and 1.52% (7/461) of the dust operation posts have an occupational health risk value of 200~399. Conclusion: there is a high rate of exceeding the standard in the dust work posts in the ferrous metal foundry enterprises in Ningbo, and the workers have a high occupational health risk of pneumoconiosis or metal and its compound pneumoconiosis. Targeted measures should be taken to reduce the occupational health risk.

[Analysis of incidence characteristics and trend of pneumoconiosis in Ningbo City from 1967 to 2019].

Objective: To understand the incidence of pneumoconiosis in Ningbo city from 1967 to 2019, and to analyze the distribution characteristics and change trend of pneumoconiosis. Methods: In February 2021, the data of pneumoconiosis patients in Ningbo city from 1967 to 2019 were sorted out. The data from 1967 to 1987 were from historical case files of Zhejiang Center for Disease Control and Prevention, the data from 1988 to 2005 were from the historical case files of Ningbo Center for Disease Control and Prevention, and the data from 2006 to 2019 were from the pneumoconiosis report card in China Disease Prevention and Control Information System; Followed up and supplement relevant information, including basic information, basic information of employers and information related to pneumoconiosis diagnosis, and comprehensively analyze the composition and development trend, population characteristics and industry characteristics of pneumoconiosis. Results: From 1967 to 2019, a total of 1715 cases of pneumoconiosis were reported in Ningbo City, including 1254 cases of stageⅠpneumoconiosis, 258 cases of stageⅡpneumoconiosis, 172 cases of stage Ⅲpneumoconiosis. 1202 cases of silicosis (70.09%) , 296 cases of asbestosis (17.26%) , 40 cases of welder's pneumoconiosis (2.33%) , 32 cases of graphite pneumoconiosis (1.87%) were reported. There were 1296 male cases (75.57%) and 419 female cases (24.43%) were reported. Silicosis (91.15%, 1102/1209) and welder's pneumoconiosis (100.00%, 40/40) were the most common pneumoconiosis in males, while asbestosis (90.24%, 268/297) and graphite pneumoconiosis (87.50%, 28/32) were the most common pneumoconiosis in females. The average age was (49.71±10.90) years old and the average length of service was (10.98±6.96) years. The top three reported pneumoconiosis cases were construction industry (336 cases, 19.59%) , ferrous metal smelting and rolling industry (317 cases, 18.48%) and non-metallic mineral products industry (315 cases, 18.37%) . The top three reported pneumoconiosis cases were 414 cases (24.14%) in Ninghai County, 294 cases (17.14%) in Yuyao City and 272 cases (15.86%) in Yinzhou District. Conclusion: With the development of industries in Ningbo City, government departments should strengthen supervision and management of enterprises involving silica dust and welding fume to curb the high incidence of pneumoconiosis.

[Occupational Health Risk Assessment of Low Concentrations Benzene Toluene and Xylenes].

Objective: To Assess occupational health risks of exposuring to low concentrations (lower than occupational exposure limit, OEL) benzene, toluene and Xylenes. Methods: Qualitative evaluation, semi-quantitative evaluation and quantitative evaluation from guidelines for occupational health risk assessment of chemicals in the workplace were conducted to assess occupational health risks exposure to benzene compounds in different workplaces of 5 manufacturing enterprises, respectively. Results: Concentrations of benzene, toluene and Xylenes in all workplaces were lower than OEL. Qualitative evaluation showed that occupational health risk level was 4 exposure to benzene and Xylenes in all workpalces, while 2 exposure to toluene. Semi-quantitative evaluation showed low level (2 of 5) risks in all workplaces exposured to benzene compounds excepted 4 workpalces exposured to benzene, the latter was moderate (3 of 5) . Quantitative evaluation gave unacceptable carcinogenic risk (higher than 10(-4)) of benzene in the wood toy manufactory, and the highest risk was (1.48~5.26) ×10(-4). The occupational health risks of benzene and Xylenes were all unacceptable (HQ>1) in 9 workplaces. Conclusion: There still need more attention to occupational health risks exposure to benzene, toluene and Xylenes lower than OEL.

[Analysis on occupational health surveillance to workers exposed to toxic environment in Ningbo].

Objective: To analyze the occupational health surveillance data of toxic and harmful workers in Ningbo, and provide scientific basis for making protective measures. Methods: To export the occupational health surveillance data of toxic and harmful workers reported by occupational health examination institutions in Ningbo during the January 1, 2011 to December 31, 2017 from the China Information System for Disease Control and Prevention, and analyze the trend of the suspected occupational disease and occupational contraindication detection rate, and compare the the health status of workers in different industry nature, economic type, enterprise scale and occupational hazards. Results: From 2011 to 2017, the number of occupational health surveillance of toxic and harmful workers in Ningbo was increasing year by year. The detection rates of suspected occupational diseases and occupational contraindications generally showed a downward trend (P<0.05) . In 2017, the distribution of occupational health care for toxic and harmful workers in Ningbo was mainly based on manufacturing (187 681/220 895, 84.96%) , private economic enterprises (103 960/220 895, 47.06%) and small enterprises (100 357/220 895, 45.43%) , Workers exposed to chemical poisons had the largest number of physical examinations (101 813/220 895, 46.09%) . The highest detection rates of suspected occupational diseases were mining industry (2/1225, 0.16%) , collective economic enterprises (4/2622, 0.15%) and small enterprises (88/100 357, 0.09%) . The highest detection rates of occupational contraindications were rental and business services (16/1 320, 1.21%) , private economic enterprises (1 190/103 960, 1.14%) and small enterprises (995/100 357, 0.99%) . In addition, workers exposed to dust had the highest detection rate of suspected occupational diseases (57/46 740, 0.12%) and workers exposed to physical factors had the highest detection rate of occupational contraindications (1207/69 567, 1.74%) . There were significant differences between the detection rate of suspected occupational disease and occupational contraindication in different industries, economic types, enterprise scale and occupational hazards (P<0.05) . Conclusion: The occupational health surveillance of toxic and harmful workers in Ningbo has been strengthened year by year, attention should be paid to small, private enterprises, and strengthen the supervision of occupational health and further standardize the work of occupational health examination so as to effectively protect the health of the occupational population.

[Analysis of acute pesticide poisoning in Ningbo city from 2011 to 2016].

Objective: To analyze the characteristics of acute pesticide poisoning in Ningbo, and to provide scientific basis for the prevention and control strategy. Methods: In February 2017, the pesticide poisoning report card of Ningbo from 2011 to 2016 was drawn from the China Disease Control and prevention information system. The data of the report card was organized by Excel and analyzed by SPSS19.0 software. Results: 2593 cases of acute pesticide poisoning were reported in Ningbo from 2011 to 2016, 125 deaths, and the case fatality rate was 4.82%. The productive pesticide poisoning and unproductive pesticide poisoning were 299 and 2294, respectively, the ratio was 1: 7.67. The case fatality rate were 0.33% and 5.41%, respectively. The difference was statistically significant (χ(2)=14.83, P<0.01). The productive Pesticide poisoning mainly occurred from July to September (55.85%) , the unproductive pesticides mainly occurred from April to June (30.64%) and July to September (30.34%). The seasonal distribution of the pesticide poisoning in the two groups was statistically significant (χ2=82.21, P<0.01). The productive pesticide poisoning in male (80.27%) was significantly higher than the proportion of unproductive pesticide poisoning (52.09%) , the differences in gender composition between the two types of pesticide poisoning was significant (χ2=84.97, P<0.01). The productive pesticide poisoning from 55 to 65 years old group was in the largest number (35.45%) , and the distribution of unproductive pesticide poisoning was uniform in each age group including 25 years old and above, the difference in age composition between two types of pesticide poisoning was statistically significant (χ2=177.84, P<0.01). All of the 10 counties of Ningbo had reports of pesticide poisoning. The counties with more reports were Ninghai county (18.28%) , Fenghua district (14.69%) and Yuyao (12.42%). The acute pesticide poisoning was mainly caused by pesticides and herbicides, mainly in organophosphorus (45.74%) and paraquat (16.81%) . Conclusions: At present, the pesticide poisoning in Ningbo is given priority to unproductive pesticide poisoning currently, seasonal distribution characteristics was obvious, and occurred both in different sex and age groups, suggesting that the relevant departments should carry out targeted health education, and strengthen the management of high toxic and highly toxic pesticides.

[Incidence and trend of occupational diseases in Ningbo, China, from 2006 to 2015].

Objective: To investigate the incidence, distribution features, and incidence trend of occupational diseases in Ningbo, China, from 2006 to 2015. Methods: In February 2016, the data on occupational disease report cards in the occupational disease and occupational health information system from 2006 to 2015 were collected to perform a comprehensive analysis of the types, incidence trend, population characteristics, and enterprise characteristics of occupational diseases. Results: There were 845 new cases of occupational diseases in Ningbo from 2006 to 2015, among which 596 (70.53%) were pneumoconiosis; there were 445 (74.66%) cases of stage I pneumoconiosis, 73 (12.25%) cases of stage II pneumoconiosis, and 78 (13.09%) cases of stage III pneumoconiosis; silicosis (59.76%) was the most common type of pneumoconiosis. Of all patients with occupational diseases, 84.97% were male, 64.50%were aged 35-55 years, and 63.67% had 5-20 working years. Most of the patients with occupational diseases worked in small and medium-sized private (or foreign) enterprises; the most common industries were black metal smelting and rolling (38.76%) , construction (17.11%) , and non-metallic ore mining (13.09%) . A total of 51.28%, 10.26%, and 7.69% of the patients with occupational poisoning worked in the electric apparatus manufacturing industry, furniture manufacturing industry, and chemical raw material and chemical product manufacturing industry, respectively. The cases of occupational diseases are mainly distributed in Yuyao City (24.62%) , Yinzhou District (23.91%) , and Ninghai County (15.62%) . Conclusion: Pneumoconiosis is the most common type of occupational disease in Ningbo and most of these patients work in small and medium-sized private (or foreign) enterprises. The supervision of small and medium-sized private enterprises should be enhanced to protect workers' health.

[The application of two occupation health risk assessment models in a wooden furniture manufacturing industry].

Objective: To explore the applicability of 2 different models of occupational health risk assessment in wooden furniture manufacturing industry. Methods: American EPA inhalation risk model and ICMM model of occupational health risk assessment were conducted to assess occupational health risk in a small wooden furniture enterprises, respectively. Results: There was poor protective measure and equipment of occupational disease in the plant. The concentration of wood dust in the air of two workshops was over occupational exposure limit (OEL) , and the CTWA was 8.9 mg/m3 and 3.6 mg/m3, respectively. According to EPA model, the workers who exposed to benzene in this plant had high risk (9.7×10-6 ~34.3×10-6) of leukemia, and who exposed to formaldehyde had high risk (11.4 × 10-6) of squamous cell carcinoma. There were inconsistent evaluation results using the ICMM tools of standard-based matrix and calculated risk rating. There were very high risks to be attacked by rhinocarcinoma of the workers who exposed to wood dust for the tool of calculated risk rating, while high risk for the tool of standard-based matrix. For the workers who exposed to noise, risk of noise-induced deafness was unacceptable and medium risk using two tools, respectively. Conclusion: Both EPA model and ICMM model can appropriately predict and assessthe occupational health risk in wooden furniture manufactory, ICMM due to the relatively simple operation, easy evaluation parameters, assessment of occupational- disease-inductive factors comprehensively, and more suitable for wooden furniture production enterprise.