RESUMEN
ObjectiveThree methods were applied to conduct occupational health risk assessment for the working positions exposed to silicon dusts in a sanitary ceramic manufacturing factory, and the evaluation results were compared to explore the applicability of different occupational health risk assessment methods. MethodsOne large sanitary ceramic product manufacturing enterprise in Songjiang District, Shanghai was selected to conduct occupational health risk assessment for the working positions exposed to silicon dusts, using occupational hazard risk index evaluation method, exposure ratio evaluation method, and International Council on Mining and Metals (ICMM) quantitative occupational health risk assessment method . The consistency of the evaluation results of the three methods was tested using weighted Kappa method. ResultsFourteen working positions exposed to silicon dusts were identified, and three positions had excessive dust concentration: composite forming position of phase 2 workshop (0.80 mg·m-3), addition forming position of phase 2 workshop (1.00 mg·m-3), and glazing position of 1F in phase 2 workshop (1.50 mg·m-3), with an excessive rate of 21.42%. The occupational hazard risk index evaluation method assessed 6 positions with no harm, 6 positions with mild harm, and 2 positions with moderate harm. The ICMM quantitative occupational health risk assessment method assessed 6 positions with potential risks, 2 positions with tolerable risks, and 6 positions with intolerable risks. The exposure ratio evaluation method assessed 8 positions with medium risk, 5 positions with high risk, and 1 position with extremely high risk. The consistency test results of the three evaluation methods were poor. The Kappa coefficient between the occupational hazard risk index evaluation method and the ICMM quantitative occupational health risk assessment method was 0.15. The Kappa coefficient between the occupational hazard risk index evaluation method and the exposure ratio evaluation method was -0.09. The Kappa coefficient between the ICMM quantitative occupational health risk assessment method and the exposure ratio evaluation method was 0.04. The RR values obtained by the three evaluation methods were significantly correlated: the correlation coefficients between RRICMM quantitative assessment method and RRexposure ratio evaluation method, RROccupational hazard risk index evaluation method and RRICMM quantitative assessment method, RROccupational hazard risk index evaluation method and RRexposure ratio evaluation method were 0.915, 0.604, and 0.594, respectively. The correlation between the assessment result level and CTWA was strong. ConclusionThe occupational hazard risk index evaluation method is suitable for the working positions with low silicon dust exposure concentration, the ICMM quantitative occupational health risk assessment method and the exposure ratio evaluation method are suitable for the positions with high silicon dust exposure concentration, but all these three evaluation methods have limitations. It is more reasonable to use multiple methods at the same time in actual evaluation work.
RESUMEN
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.