| Summary: | 碩士 === 長榮大學 === 職業安全與衛生學系碩士班 === 104 === The process of alloying is used to change the chemical composition of steel and improve its properties over carbon steel or adjust them to meet the requirements of a particular application by adding manganese, nickel, copper or chromium elements. Because of the emmision of metal dust during the manufacturing process, the workers will expose to high concentration of metal dust and increase the health risk.
Three alloy manufacturing plants were chosen in this study. 14 area samples and 7 urine samples were collected from plant A. In B plant samples included 7 personal and 33 area air samples,7 worker urine samples and 4 administrative worker urine samples. C plant’s samples were collected from 23 area samples, 21 labor urine samples and 4 administrative regions urine samples.
The metal concentrations of these samples were analyzed by inductively coupled plasma mass spectrometry (ICP/MS). The metal concentrations in workplace were lower than those of permissible exposure limits. The metal concentrations in the administrative area were also lower than those in the workplace. The iron level was 421.90 g/m3 in post-treatment area of plant A. The zinc level was 145.24 g/m3 in smelting area of plant B. The place near the smelting area had higher zinc concentration. The results of urine samples of plant C indicated that the concnentrations of chromium and cadiumin some workers’ urine samples were higher than those BEI recommended by ACGIH.(25 and 5 ug/g Cr).
The metal concentrations in air were lower than those of permissible exposure limits. The metal concentrations in the administrative area were lower than those in the workplace. According to the guidelines for exposure assessment, issued by the United States Environmental Protection Agency (USEPA), health risk assessment indicated the cancer risk of Cr6+ exceeded acceptable cancer risk standard (10-5~10-6) for three plants. And hazard index of manganese at A and C plants exceeded the acceptable standard, 1.
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