Detection of arsenic exposure with speciated arsenic metabolites and immunological function for copper-foil workers

[[abstract]]砷化合物廣泛地分佈於自然界中，可經由工業製造等方式進入生活環境中。銅精煉廠需要用到砷化合物作為活化劑，會排放含三氧化二砷的氣態膠，作業勞工可能有砷化合物暴露與危害之虞，流行病學研究證據顯示砷化合物的暴露與人類之癌症罹患有關。本研究主要目的在探討職業上不同工作類型之三氧化二砷暴露，在人體之各類砷代謝物濃度與是否影響人體免疫系統功能。針對銅箔工廠123位員工進行職業健康問卷調查、血中總砷測定、尿中各種砷代謝物測定 (三價砷、五價砷、單甲基砷及二甲基砷)、觀察血液中免疫功能變化 (T-helper、T-cytoxic、T細胞上之IL-2 receptor及T細胞增生情形)及白血球反應性氧化物質含量 (O2-.及H2O2)，經過肌酸酐校正、3天前食用海鮮及肝功能異常的篩除，以70人進行結果分析，藉此瞭解勞工砷的健康危害情形。研究結果顯示，有砷特殊健檢勞工與無砷特殊健檢勞工之尿中各種砷物種分析、血中總砷、免疫功能變化分析及白血球反應性氧化物質含量測定，皆沒有顯著相關。本研究以工作型態分類，發現暴露組勞工尿中三價砷、尿中無機砷、尿中二甲基砷、尿中有機砷及尿中無機砷代謝物總和濃度皆顯著高於對照組勞工 (P<0.05)。且暴露組中未配戴呼吸防護具勞工之尿中無機砷代謝物總和濃度高於有配戴呼吸防護具勞工，兩者尿中無機砷代謝物總和濃度相差37.5%。尿中無機砷≧3μg/g勞工白血球反應性氧化物質H2O2顯著低於尿中無機砷濃度<3μg/g creatinine勞工 (P<0.05)。尿中無機砷≧5μg/g creatinine勞工免疫功能變化分析-T-cytoxic顯著高於尿中無機砷濃度<5μg/g creatinine勞工 (P<0.05)。研究發現尿中無機砷上升可能刺激T-cytoxic的升高，但另一方面卻造成白血球反應性氧化物質的下降，顯示在較低濃度之砷暴露，並未透過白血球反應性氧化物質之路徑而影響免疫功能。作業時全程配戴個人防護具將有效減少砷暴露。[[abstract]]Arsenic (As) is widely distributed in nature and released into the environment through industrial processes. The Copper-foil industry needs to use arsenic compound as the activator, it discharge air aerosol including arsenic trioxide, arsenite (As3+). Workers may occupationally expose in the arsenic compound and has hazardous. The objective of this study is to determine whether occupational exposure to arsenic trioxide had adverse effects on immunological function. One hundred and twenty-three As-exposed workers in a copper-foil plant in southern Taiwan were recruited. Total blood arsenic concentrations and urinary arsenic metabolite concentrations, including As3+, arsenate (As5+), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) were measured and quantified by High-Performance Liquid Chromatograph (HPLC) and Flow Injection Atomic Absorption Spectrometric (FI-AAS). The CD markers of T-helper, T-cytoxic, T-cell IL-2 receptor, and T-cell proliferation for immunological function as well as reactive oxygen species (ROC) generation of white blood cells (WBC) were analyzed using flow cytometry. There were no significantly differences for blood total arsenic concentrations, urinary arsenic metabolite concentrations, CD markers, and ROS generation of WBC between the workers who need to do the specific physical examination (SPE) for As and the workers who unnecessary to do SPE for As. The classification of work type were conducted and we found that levels of urinary As3+, arsenate (As5+), total inorganic As (Asi), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and total As of the As-exposed workers were significantly higher than the control group (P<0.05, respectively). Among the As-exposed workers, we found that total urinary As levels of the workers with personal protection equipment were significantly higher than the workers without personal protection equipment. In addition, the use of personal protection equipment was significantly associated with decrease of urinary total As (37.5%). The percentage of T-helper of the workers for Asi≧5μg/g creatinine was significantly higher than the workers did in Asi<5μg/g creatinine group (P<0.05). On the other hand, levels of WBC H2O2 generation for Asi≧3μg/g creatinine group were significantly lower than the workers did in Asi<3μg/g creatinine group (P