| 摘要: | 目的：本研究主要是透過橫斷式的研究設計，進行國內某薄膜電晶體液晶顯示器(Thin Film Transistor-Liquid Crystal Display,TFT-LCD)廠勞工作業環境之噪音和揮發性有機物的暴露評估，並且探討不同部門勞工在高血壓、肝功能及腎功能異常之盛行率差異。
方法：本研究以某家TFT-LCD廠約2162名的員工作為研究族群，進行全廠區之現場訪視及基本資料收集。我們針對不同製程之工作站點利用TES-1358八音度音頻分析儀及ENTECH不銹鋼採樣筒，進行環境噪音及揮發性有機物之測量；並且針對噪音平均值≧75分貝之工作站點進行500Hz、1,000Hz、2,000Hz、3,150Hz、4,000Hz及8,000Hz的頻譜分析。我們徵求562名自願者填寫生活習慣問卷，並且收集到155名勞工健檢資料進行健康狀況評估。在資料分析方面，對於連續變項我們根據資料是否呈常態分佈而選擇ANOVA或無母數統計(Kruskal-Wallis test)來分析不同部門間之差異；對於類別變數，則以卡方檢定來進行不同部門間之比較。我們以邏吉斯廻歸模式來分析高血壓、肝功能異常及腎功能異常與不同部門間的關聯性。
結果：我們發現Array區( 74.3 ± 3.7分貝)及Cell區( 71.8 ± 2.0分貝)的噪音測量值顯著低於Module區( 75.6 ± 3.4分貝)，而且在Array區之薄膜清洗及Module區之印刷電路板測試(Printed-Circuit-Board,PCB)工作站點的平均噪音值高於80分貝。而噪音頻譜分析結果顯示，Array區的薄膜清洗、薄膜機群、去光阻和乾蝕刻、Cell區的切割及Module區的PCB測試、背光模組組立、積體電路(Integrated Circuit,IC)外框組立、控制板、老化測試及包裝機器工作站點在頻率為4,000Hz或8,000Hz之噪音值高於其他頻率。在TFT-LCD廠內，揮發性有機物平均濃度最高的三種物質為：乙醇( 1302.2 ± 1493.8 ppb)、丙酮( 709.8 ± 586.5 ppb)及異丙醇( 297.3 ± 395.3 ppb)；而以總揮發性有機物來看，Module區( 4651.4 ± 1855.4 ppb)顯著高於Array區( 1867.2 ± 1161.9 ppb)及Cell區( 2775.2 ± 1878.3 ppb)。在健康狀況方面，Array區相較於Module區有顯著較高的腎功能異常風險(盛行率對比值為3.84，95%信賴區間=1.02-14.40)，然而在高血壓風險及肝功能異常風險三個部門都沒有達到統計上顯著的差異。
結論：本研究結果顯示此廠區的工作環境噪音平均值低於80分貝，但在薄膜清洗及印刷電路板測試之工作站點其平均值仍高於80分貝；而且在4,000Hz或8,000Hz頻率有最高的噪音值。Array區相較於Module區有較高的腎功能異常風險。我們建議未來研究能進行個人量測，以更清楚勞工暴露情形；並且持續追蹤及評估勞工的健康狀況，以釐清職業暴露與健康影響的因果關係。
Objectives: The aims of this study were to investigate the exposure to noise and volatile organic compounds (VOCs) and to determine the prevalence rates of hypertension, liver dysfunctions and kidney dysfunctions among workers in a thin-file transistor-liquid crystal display (TFT-LCD) company.
Methods: We selected a TFT-LCD manufacturing company with 2162 employees as the studying population to perform the walk-through survey. Octave-band analyzers (TES-1358) and ENTECH canisters were used to determine the environmental noise and VOCs in the workplaces of array, sub-array, cell, and module processes. We measured the frequency distributions at workstations with environmental noise above 75 dBA for pure tone frequencies of 0.5,1.0,2.0,3.5,4.0 and 8.0 KHz. We collected self-administered questionnaireS from 562 workers and obtained health-checkup data from 155 volunteers to perform the health assessment. We used the one-way analysis of variance (normal distribution) and the Kruskal-Wallis test (abnormal distribution) for continuous variables and the Chi-square test for dichotomous variables among different departments. Logistic regression models were performed to investigate the worker’s health status by work area controlling for related confounders.
Results: The mean values noise levels were significantly lower in both array processes (74.3±3.7 dBA) and cell processes (75.5±3.4 dBA) than in module processes (75.6±3.7 dBA). Workstations of file-washing in array processes and print-circuit-board (PCB) testing in module processes had the average noise level above 80 dBA. The mean noise levels at 4K or 8K Hz were significantly higher than those at other frequencies at workstations of file-washing, developing, stripping and dry-etching in array processes and cell-cut in cell processes, as well as those measured at PCB testing, backlight-unit assembly, integrated circuit composing, glass panel fabrication , aging testing and packaging in module processes. We also found that ethanol (1302.2 ± 1493.8 ppb), acetone (709.8 ± 586.5 ppb) and isopropyl alcohol (297.3 ± 395.3 ppb) were the three dominant solvents used in this TFT-LCD company. The average concentration of total VOCs in module processes (4651.4 ± 1855.4 ppb) was significantly higher than those in array processes (1867.2 ± 1161.9 ppb) and cell processes (2775.2 ± 1878.3 ppb). We found that workers in array processes were at higher risk of kidney dysfunction than those in module processes (odds ratio=3.84, 95% confidence interval=1.02-14.40). However, there were no significant differences in risks of hypertension and liver dysfunction among these three groups.
Conclusions: Our findings revealed that environmental noise in this TFT-LCD company had the average value below 80 dBA except some workstations. The noise levels at 4,000 Hz or 8,000 Hz are the highest among all meansured pure tone frequencies. Array workers are at higher risk of kidney dysfunction compared to workers in module processes. We suggest further studies with more detailed measurements of personal exposures and a longer follow-up to investigate the relationship between occupational exposure and health effects among TFT-LCD workers. |
