氧化銦錫作業勞工暴露影響評估

The Exposure Assessment of the Indium-Tin Oxide (ITO) Processes Workers

蔡宗穎(Tsung-Ying Tsai)

指導教授 ： 劉宏信

中山醫學大學/健康管理學院/職業安全衛生學系碩士班/碩士(2014年)

https://doi.org/10.6834/CSMU.2014.00196

摘要

目的：氧化銦錫(Indium-Tin Oxide, ITO)是由氧化銦與氧化錫混合燒結而成，其混合比例會依照其需求做改變，如面板產業大多以90：10 (重量比) 混合燒結。到2014年5月共有15名工人因暴露氧化銦錫顆粒導致肺部疾病被報導，分別為日本10例、美國4例以及中國1例。個案研究、流行病學調查以及動物研究方面，結果顯示氧化銦錫等銦化合物可能對人體或動物之肺部產生損傷。本研究的目的是透過生物偵測採樣調查我國ITO相關作業場所勞工ITO暴露風險評估。
材料與方法：本研究選定我國ITO相關作業場所作業勞工(945人)，分別來自5間公司，其中A與B公司為氧化銦錫濺鍍靶製造公司，C、D、E等3間公司則為液晶顯示器製造廠。參與受測的勞工都會填寫個人資料、生活習慣及職業史等健康調查問卷及簽暑人體試驗同意書，其次依據勞工之作業性質區分為暴露組(668人)與對照組(277人)，並採集勞工血液及尿液檢體以感應耦合電漿質譜儀進行血清及尿液中銦濃度分析，此外亦進行氧化性傷害及彗星試驗(Comet Assay)等生物監測指標的分析，最後使用SPSS(Statistical Product and Service Solutions) 18.0軟體來進行統計分析。
結果：勞工整體的血清中銦平均濃度為1.40±2.43μg/L，血清中銦濃度與尿中銦濃度進行相關性分析，結果表明具有高度的顯著性正相關，其相關係數為0.596 (p<0.001)。暴露組勞工血清中銦濃度與尿液中銦濃度皆顯著(p<0.001)高於對照組。若將暴露族群依工作年資分成3組(A：<3年；B：3~5年；C：>5年)來觀察，結果發現血清中銦濃度與尿中銦濃度會隨著工作年資而增加。另外，本研究亦對62名勞工進行3年度追蹤的生物性監測，當勞工長期使用動力過濾式呼吸防護具後(Powered Air Purifying Respirators, PAPR)，血清中銦含量會逐年下降，各項生物監測指標也開始下降，且隨工作年資增加而TMOM有增加之趨勢。
結論：應該對氧化銦錫的毒性作用作更深入的研究，並做好完善的保護措施，以避免工人的氧化銦錫暴露。定期健康檢查將能早期發現健康危害，防止勞工因暴露氧化銦錫所帶來的損傷。長期使用動力過濾式呼吸防護具可改善作業人員血清中銦濃度，但即使暴露在極低濃度的ITO粉塵下，若未使用適當防護具或有良好之SOP，由於溶解度不佳可在肺部累積，導致作業人員血清中銦濃度並無法下降。

關鍵字

暴露 ； 氧化銦錫 ； 感應耦合電漿質譜儀 ； 血清 ； 尿液

並列摘要

Aim: Indium-Tin-Oxide (ITO) is a sintered mixture of indium- oxide (In2O3) and tin-oxide (SnO2) with percentages of 90% and 10% (wt/wt) , is used as a transparent conductive coating for liquid crystal displays (LCDs). Until May, 2014, ten cases of interstitial pneumonia in Japanese, four cases of pulmonary alveolar proteinosis (PAP) in US, and one case of PAP in Chinese were found among workers exposed to indium. Case reports, epidemiological studies and animal studies all reveal that exposure to the hardly soluble indium compounds causes interstitial pneumonia as well as emphysematous lung damages, which is so-called “Indium Lung”. The purpose of this study was to assess domestic ITO workers exposure and risk in terms of biological monitoring.
Methods: 945 workers were recruited from five domestic ITO and LCD manufacturing plants in this study, in which 668 were exposed workers and 277 were control ones. Each employee was asked to fill out a questionnaire for obtaining information about personal characteristics, life style and occupational history. Inductively coupled plasma mass spectrometry (ICP-MS) was used to analyze the serum and urine indium concentrations. The whole blood samples were analyzed oxidative stress and comet assay. The SPSS 18.0 software packages were used for data management and statistical analysis.
Results: Overall average serum concentration with standard deviation of indium exposed worker was 1.40±2.43 (μg/L). Significant positive relationships were found between Serum-In and Urine-In levels. The correlation coefficient was 0.596 (p<0.001)。Serum-In and Urine-In levels of the exposure group were significantly higher than those of the control group. We also according on exposure work years were divided into three groups (A: <3 years; B: 3 ~ 5 years; C: >5 years) in this study. Serum-In and Urine-In levels were increased with exposure time. Based on three years follow-up results, the decreasing trends of oxidative stress and serum indium of 62 workers were found. It demonstrated the protection effects of PAPR and application of good management practice. The increasing trends of TMOM depend on the exposure time.
Conclusions: Based on our findings, the possible toxic effects of indium-tin oxide should be paid more attention, and maximum health care measures should be taken to protect workers exposed to ITO. Early detection of health outcomes can prevent any further damages from indium-tin oxide exposure. Significant decrease in Serum-In levels were found in workers wearing PAPR for at least 2 years. In spite of the lower ITO dust exposure concentration in the workplace. It can be accumulated in lung due to hardly soluble property. This may lead to chronic adverse health effects. Therefore, appropriate control measures and proper management practice are important for reduceing indium exposure reduction of indium.

並列關鍵字

Exposure ； Indium- Tin Oxide ； ICP-MS ； Serum ； Urine

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