砷化鎵磊晶製程砷暴露危害預防與員工健康指標研究

Abstract

本研究針對國內具砷化鎵製程高科技產業公司進行研究，共回收二十一家砷化鎵產業砷作業與含砷物質處理方式問卷調查表，調查結果顯示約62%的公司於近5年內成立，約33%的公司為近10年成立之公司，合計約95%，顯見砷化鎵製程領域公司為國內新興科技行業。屬砷化鎵磊晶製程公司約93%的公司使用金屬有機物化學氣相沈積機台，另分子束磊晶及液相磊晶成長機台使用的公司則各只有1家廠商使用，顯示國內從事砷化鎵磊晶製程公司以金屬有機物化學氣相沈積法為主，但普遍面臨含砷廢棄物處理問題，除了認定及廢棄物分類外，在國內找不到合法或願意處理廢棄物之公司為廠商最困擾事項。而且砷化鎵基板尚未有廠商執行研磨後再使用，因此從事砷化鎵磊晶製程公司採取廠內儲存或少部分委外資源回收及固化處理；對於稀有性鎵金屬無再利用機制，此部分亦可能與國內無再回收利用公司有關。 本研究並針對某砷化鎵磊晶製程公司砷作業勞工進行健康問卷調查、作業環境空氣中砷測定與生物暴露指標測定，結果顯示砷暴露勞工與對照組作業勞工之年齡、工作年資、有抽煙習慣者、有喝酒習慣者、有糖尿病症狀者、有氣喘症狀者、有過敏性鼻炎者、有過敏性皮膚炎者、與有腎臟病者，以卡方分析，皆沒有顯著差異存在。某砷化鎵磊晶製程公司不論個人採樣或區域採樣之空氣中總砷濃度皆低於行政院勞工委員會所規範總砷的日時量平均容許濃度標準，空氣中總砷濃度與各別血中總砷濃度、尿中As(III)、尿中As(V) 、尿中Asi、尿中MMA、尿中DMA、尿中無機砷代謝物總和濃度、頭髮總砷、腳趾甲總砷濃度，則皆沒有顯著相關性存在；但空氣中總砷濃度與手指甲總砷濃度之相關係數0.820，呈顯著正相關（p=0.013），可見低濃度砷的累積性暴露不容忽視，在進行砷作業製程保養維修時，請工作人員務必戴上呼吸防護具與穿上防護衣及戴上手套，避免作業人員直接身體暴露接觸，因為防護具是防止危害的最後一道防線。

This research studied the high technology companies with gallium arsenide process. questionnaires of 21 advanced technology companies with effective gallium arsenide manufacture capabilities were collected. The questionnaire investigation revealed that 62% of the advanced technology companies were established within 5 years, and 33% of the advanced technology companies were established within 10 years. Thus, 95% of the 21 advanced technology companies were newly formed. 93% of the gallium arsenide epitaxy production companies using metal organic chemical vapor deposition (MOCVD) machine to produce GaAs based Epitaxial layers. There was only one gallium arsenide epitaxy production company using the machines of molecular beam epitaxy and liquid phase epitaxy. It revealed that most gallium arsenide epitaxy production companies used MOCVD. These companies faced the problem of arsenic wastes treatment. Besides identification and classification of wastes, the most serious problem was these companies can not find the legal or qualified companies to deal with arsenic wastes in domestic area. No company can grind and recycle the wastes of gallium arsenide substrates. Therefore, majority of these companies store gallium arsenide substrates wastes in their factories, others commissioned foreign companies to recycle or solidify wastes. The reason for no recycling mechanism for rare gallium metals was probably due to no existing recycling company for gallium in Taiwan. This study also surveyed the workers exposed to arsenic in one advanced technology company which grows gallium arsenide epitaxyal layers. The study includes environmental monitoring for arsenic, and biological monitoring of arsenic. By using the Chi-Square test, the arsenic exposed workers group and the workers group with no arsenic exposure shows no significant differences no matter the age, working time, smoking status, alcohol consumption, diabetes, asthma, allergic rhinitis, allergic dermatitis, and kidney disease status. The total arsenic concentrations for samples collected from personal sampling and area sampling in the company were both lower than the permissible exposure limit of time weight average authorized by the Council of Labor Affairs, Executive Yuan. The total arsenic concentrations in air can not be correlated significantly with the trivalent arsenic concentration, pentavalent arsenic concentration, monomethylarsonic acid (MMA) concentration, dimethylarsinic acid (DMA) concentration, and total inorganic arsenic metabolites concentration, and the total arsenic concentration in hair, total arsenic concentrations in toenail, in urine. Howere, there was significantly positive correlation between the total arsenic concentrations in air and the total arsenic concentration in fingernail. Thus, the accumulation of low level arsenic exposure can’t be ignored. The maintenance personnel in the exposed arsenic enviroment should wear respirator, protective clothing, and protective glove, because the protective equipment is the last way to prevent exposure to the hazard arsenic enviroment.