電弧爐煉鋼廠作業勞工多氯戴奧辛／呋喃暴露評估研究

Exposure Assessment of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans (PCDD/Fs) for Workers of Secondary Ferrous Metal Smelting Refining Plant -Electric Arc Furnace

本研究之目的在了解評估電弧爐煉鋼業勞工血液中多氯戴奧辛/ 呋喃(polychlorinated dibenzo-p- dioxins and dibenzofurans, PCDD/Fs）濃度與作業環境空氣暴露及健康指標如血液生化檢查、荷爾蒙及免疫指標之相關性。本研究依據職務及多氯戴奧辛／呋喃暴露可能性選取某電弧爐煉鋼廠 45 名作業勞工為研究對象，進行作業環境空氣及血液中 PCDD/Fs 檢測、一般臨床生化、荷爾蒙及免疫指標分析。並以問卷調查勞工基本資料、飲食、時間活動模式等暴露相關因子。結果顯示，電弧爐區和澆鑄區空氣中PCDD/Fs毒性當量濃度分別為1.609及2.013 pg WHO98-TEQDF/Nm3 ，主要貢獻來自五、六氯呋喃及四、五、六氯戴奧辛。依作業勞工依職務及年資區分為高、低暴露族群，其血液中 PCDD/Fs 濃度分別為24.0、及13.8 pg WHO98-TEQDF/g lipid，高暴露族群高於低暴露族群（P<0.001）。同源物分析顯示毒性貢獻主要來自於五、六氯呋喃及四、五、六戴奧辛，高暴露族群均高於低暴露族群，且與空氣樣本一致。高暴露族群在總甲狀腺素（Total Thyroxine）之測值低於低暴露族群，其餘飲食習慣、13項血液生化檢查及五項荷爾蒙在二族群均無顯著差異。迴歸分析顯示血液中 PCDD/Fs 與年齡、身體質量指數（body mass index; BMI） 、現職年資、電弧爐廠總年資具高度相關性，且達統計上顯著意義，顯示電弧爐煉鋼廠資深勞工之 PCDD/Fs 暴露可能和作業環境有關，建議應加強煉鋼過程逸散污染物之收集及處理，強制配戴適當之呼吸防護具，並定期追蹤勞工血中 PCDD/Fs 及進行健康檢查，以確保勞工之健康。

The objective of this research was to assess the associations among serum PCDD/Fs levels of workers, working environmental exposure, and health indices such as serum biochemical test, hormones and immunological index of workers in secondary ferrous metal smelting refining plant, Electric Arc Furnace (EAF). According to job activities and the possibility of exposure to PCDD/Fs, 45 workers employed at an EAF factory were selected as subjects. The airborne PCDD/Fs, serum PCDD/Fs, blood biochemistry and hormones examination, immunological index were investigated. The levels of airborne PCDD/Fs at the EAF and casting area were 1.609 and 2.013 pg WHO98-TEQDF/Nm3, respectively. The PeCDF, HxCDF, TCDD, PeCDD and HxCDD contributed the most of TEQ. The workers were classified into high and low exposure groups by the job activities and seniority. The serum PCDD/Fs of high exposure group (24.0 pg-WHO-TEQDF/g-lipid) was significantly higher than those of low exposure group (13.8 pg-WHOTEQDF/ g-lipid)(p<0.001). The levels of PeCDF, HxCDF, TCDD, PeCDD and HxCDD in high exposure group were significantly higher than low exposure group, and the homologue pattern of serum PCDD/Fs was the same as airborne PCDD/Fs. Total thyroxine in high exposure group was significantly lower than that in low exposure group. There are no significant differences between the two groups in blood biochemistry, hormones, and dietary patterns. However, the concentrations of serum PCDD/Fs were highly correlated with age, BMI, and seniority. The workers were exposed to higher concentration of PCDD/Fs emitted from EAF. The usage of personal protective equipment was suggested to reduce the exposure of PCDD/Fs.