探討襯墊黏貼作業區勞工甲苯之長期暴露特徵

To characterize worker long-term exposure to toluene in the pad pasting working area

張芳瑜(Fang-Yu Chang)

指導教授 ： 王櫻芳

中山醫學大學/健康管理學院/職業安全衛生學系/碩士(2021年)

https://doi.org/10.6834/csmu202100199

摘要

本研究在某一工具機廠中之襯墊黏貼作業區，結合直讀式儀器之長期量測與透過勞工個人環境採樣及生物偵測之分析結果，藉由貝氏統計進行決策分析，以提供事業單位控制措施或管理方案擬定之參考。
本研究對對襯墊黏貼作業區使用甲苯之勞工進行暴露調查，利用直讀式儀器(Photoionization Detector, PID)進行多天不同時段TVOCs之監測，此結果建構長期勞工暴露之濃度範圍為0.19~59.16 ppm；再以活性碳管進行甲苯之環境採樣以及同步收集兩位勞工上班前至工作後之間的尿液中甲苯代謝物馬尿酸濃度，其中分別以氣相色層分析質譜儀和高效能液相層析分析儀進行分析。
藉由直讀式儀器PID長期量測與空氣中甲苯暴露濃度之線性回歸方程式: yair = 0.892xPID-0.5955，可推得出該作業場所長期在空氣中甲苯濃度暴露情形，作為其事前分佈(prior)；另外，空氣暴露與體內生物偵測代謝指標物間之方程式:yurine = 0.006xair + 0.0004，可以推估長期暴露之尿中馬尿酸濃度，作為可能性分佈(likelihood)，最後透過貝氏統計分析，以推估勞工長期暴露實態之事後分佈(posterior)。研究結果顯示，長期襯墊黏貼作業區推估之甲苯濃度為2.41±0.52 ppm，而經肌酐酸校正後長期推估之馬尿酸濃度為0.00923±0.00361 (g-HA/g-CR)，皆係屬可接受之容許濃度標準範圍內。
因此根據環境偵測與生物偵測方面，透過其兩者之間的相關性(R² = 0.9445)，也證實了甲苯代謝物馬尿酸此生物指標，可以有效地來評估襯墊黏貼作業區勞工暴露到甲苯之暴露情形。在貝式決策分析後，事後分佈之結果顯示出，發現此一作業勞工長期甲苯之暴露落在0.1PEL~0.5PEL之機率為39.7%，雖符合法令規範，但考量即使長期在低濃度之暴露下，若相關安全防護設施及管理不當，可能會對勞工眼睛、皮膚、呼吸系統、中樞神經系統、肝臟及腎臟等器官產生危害。所以，事業單位需應擬定相關管理或控制策略，以減少勞工在作業中之暴露危害。

關鍵字

甲苯 ； 直讀式儀器 ； 生物偵測 ； 貝氏統計 ； 長期暴露推估

並列摘要

This study was set to establish exposure predicted model by combining personal environmental and biological monitoring data and direct-reading instrument monitoring results during the pad pasting process in a machine tool factory. The decision analysis is performed by Bayesian statistics to provide reference for the formulation of control measures or management plans for workplaces.
This study conducted while workers exposure to toluene in the pad pasting working area. The direct-reading instruments (Photoionization Detector, PID) were used to monitor TVOCs for multiple days and different periods of time. As a result, the concentration range of long-term exposure was constructed to be 0.19~59.16 ppm; and then activated carbon tube was used to conduct environmental sampling of toluene and simultaneously collected the concentration of toluene metabolite hippuric acid in the urine of two workers between before work shift and after work shift, which were analyzed by gas chromatography mass spectrometer and high performance liquid chromatography analyzer.
The linear regression equation of the toluene exposure concentration in the air and the long-term PID measurement was yair = 0.892xPID-0.5955, it can be deduced that the workplace has long-term exposure to toluene concentration in the air as its prior distribution. In addition, the correlation between air exposure and biological monitoring metabolic indicators in the body was yurine = 0.006xair + 0.0004, which can be used to estimate the concentration of hippuric acid in urine for long-term exposure as the probability distribution. Finally, Bayesian statistical analysis was used to estimate the posterior of the long-term exposure. The results of the study show that the estimated toluene concentration in the long-term pad pasting working area is 2.41±0.52 ppm, and the long-term estimated hippuric acid concentration after correction for creatinine acid is 0.00923±0.00361 (g-HA/g-CR), both of which are acceptable within the standard range.
Therefore, according to environmental detection and biodetection, through the correlation between the two (R² = 0.9445), it has also been confirmed that the toluene metabolite hippuric acid is a biological indicator that can effectively assess the exposure of workers in the pad pasting working area to toluene. After the Bayesian decision analysis, the results of the posterior distribution show that it is found the long-term toluene exposure of these workers falls within 0.1PEL~0.5PEL, the probability is 39.7%. Although it complies with laws and regulations, it is considered that even under long-term exposure to low concentrations, if the relevant safety protection facilities and management are improper, it may cause harm to the workers’ eyes, skin, respiratory system, central nervous system, liver, kidneys and other organs. Therefore, it is necessary to formulate related management or control strategies to reduce the exposure hazards of workers in the operation.

並列關鍵字

Toluene ； Direct-reading instruments ； Biological monitoring ； Bayesian statistical analysis ； Long-term exposure estimation

參考文獻

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