二鄰氯苯胺甲烷之採樣分析研究

A Study of Sampling and Analysis of 4, 4’-Methylene bis (2-chloroaniline)

2002 年在我國因二鄰氯苯胺甲烷 (4,4’-Methylene bis (2-chloro aniline, MOCA)，造成疑似職業性膀胱癌案例，亦是全世界首例。因此建立穩定和精確的採樣分析方法有其急迫性需求。本研究針對二鄰氯苯胺甲烷做採樣及分析方法改進之研究，以改進現行法規中各種採樣建議方法，使其更能精確評估作業環中勞工暴露濃度，並同時探討較簡易的萃取和採樣方法之可行性。研究以玻璃纖維濾紙進行採樣，並以甲醇萃取樣品，使用高效率液相層析儀和紫外──可見光偵測器進行樣品的分析。經實驗評估，檢量線線性相關係數高於 0.999 以上，偵測極限可達 16.63 pg，再現性之變異係數低於 6%，在三種 PEL 濃度之回收率可介於 100.5% 至 101.2% 之間，濃度變異係數（CV%）及分析變異係數（CVa%）分別在 0.70% 和 0.60% 以下。玻璃纖維濾紙樣品置於室溫，儲存穩定性可維持 28 天以上， QC 樣本之變異係數低於 4%，短時間二重複分析之相對差異百分比可在 0.5% 以內，在 MOCA 的捕集上，玻璃纖維濾紙具有良好的效果。將此方法應用於職場也獲得良好的結果。

In 2002, a worker was diagnosed with bladder cancer in Taiwan. Suspecting that exposure to 4,4’ -Methylene bis(2-chloroaniline, MOCA) at work was the main cause of the disease, a group of researchers were anxious to establish a sampling and analytical method to measure the chemical with adequate reliability and accuracy. For this study, glass fiber filters were used to collect MOCA particles, followed by extraction with methanol and measurement with an HPLC-UV detector. An excellent calibration result, with a relative linear correlation greater than 0.999, a detect limit of 16.63 pg, and an average correlation variation of 6% in reproducibility, was achieved. The recovery rates for three different levels of permissible exposure limit (PEL) ranged from 100.5% to 101.2%, and coefficients in variations of concentrations (CV%) and analyses (CVa%) of 0.70% and 0.60%, respectively, were obtained. Samples stored with glass fiber filters were kept for 28 days with a coefficient of variation with quality control samples lower than 4%. The relative percentage difference for short-term duplication analysis was lower than 0.5%. Used in the workplace, this method can produce good results. It is confirmed that glass fiber filters produce good results in the collection of MOCA samples.