晶圓廠離子植入機台維修人員尿中砷物種分析

Abstract

半導體晶圓製造過程中，維修工程師 在拆卸機台進行保修作業時有可能暴露到 危害物質，特別是作業環境中的砷或砷化 物。本研究以高效能液相層析儀結合原子 吸收光譜儀進行維修工程師的尿中砷代謝 物種分析，以瞭解其維修作業中可能的砷 暴露。共有30 名來自六家不同晶圓廠的維 修工程師被列為暴露組，另每家晶圓廠兩 名工業衛生師共12 人組成對照組。於機台 維修當週，針對暴露組與對照組的研究對 象連續七天採集每日早起第一泡尿液樣 本。尿中三價砷、五價砷、單甲基砷酸、 二甲基砷酸及總無機砷代謝物平均濃度分 別為1.7±1.4 ug/L, 1.4±1.1 ug/L, 6.2±6.7 ug/L, 20.2±14.1 ug/L, 29.5±17.2 ug/L 。單甲 基砷酸及其佔尿中總無機砷代謝濃度百分 比在對照組、無保養作業的維修工程師及 有保樣作業的維修工程師之間分別呈現遞 增趨勢(p<0.005 及 p<0.0005)。本研究也指 出低濃度砷暴露情況下，尿中總無機砷代 謝濃度可能會受食物中砷醣的干擾而誤導 無機砷暴露量的測量。然而在此情況下， 以尿中砷物種分析觀察單甲基砷酸比例的 變化是一項適當有用的指標，足以確定暴 露的存在。

For the wafer fabrication in semiconductor industry, the maintenance engineers are potentially exposed to hazards during their work of disassembling machine compartments for clean-up. One special concern is arsenic or arsenic compounds in working environment. The present study analyzed speciated urinary inorganic arsenic metabolites of the maintenance engineers with HPLC-HG-AAS to study the potential arsenic exposure during their maintenance work. Totally, from 6 wafer fabrication facilities, 30 maintenance engineers were recruited as exposed group, so were the another 12 office-based industrial hygienists serving as control group. First morning voided urine samples of each study subject were collected for 7 consecutive days. Results show the levels of total urinary inorganic arsenic metabolites for exposed group were 1.7±1.4 ug/L, 1.4±1.1 ug/L, 6.2±6.7 ug/L, 20.2±14.1 ug/L, 29.5±17.2 ug/L for As 3+ , As 5+ , monomethylarsonic acid, dimethylarsinic acid and total inorganic arsenic, respectively. Both concentration of monomethylarsonic acid and its proportion among various urinary inorganic arsenic metabolites showed significantly ascending trend among control group, engineers without preventative maintenance work prior to their urine sampling, and those with such work prior to sampling (p<0.005, and p<0.0005, respectively). It was aslo suggested that, at low level occupational arsenic exposure, the concentration of total urinary inorganic arsenic metabolites might be misleading due to the confounding effect of arsenosuger coming from seafood. Nevertheless, speciation of urinary arsenic species is good and appropriate in such case to use the proportion change of monomethylarsonic acid as an indicator for the verification of arsenic exposure.