A Method for Routine Analysis of Urinary 4,4′‐methylenebis (2‐chloroaniline) by Gas Chromatography‐Electron Capture Detection

Abstract

A Method for Routine Analysis of Urinary 4,4‘‐methylenebis (2‐chloroaniline) by Gas Chroma‐tography‐Electron Capture Detection: Akito TAKEU‐CHI, et al. Osaka Occupational Health Service Center, Japan Industrial Safety and Health Association— Objectives The purpose of this study was to develop a simple and cost‐effective method for the determination of urinary 4,4‘‐methylenebis (2‐chloroaniline) (MBOCA) by gas chromatography‐electron capture detection (GC‐ECD) for biological monitoring of occupational exposure to MBOCA. Methods MBOCA was prepared by liquidliquid extraction after alkaline hydrolysis, derivatized with N‐methyl‐bis (trifluoroacetamide) and then analyzed using GC‐ECD. The proposed method was validated in accordance with the US Food and Drug Administration guidance. Results The calibration curve showed linearity in the range 1–100 μg/l, with a correlation coefficient of >0.999. The limits of detection and quantification were 0.3 μg/l and 1 μg/l, respectively. The recovery was 94−99%. Intraday accuracy, expressed as the deviation from the nominal value, was 90.5−100.3%, and intraday precision, expressed as the relative standard deviation, was 0.3−2.4%. Interday accuracy and precision were 87.8−100.2% and 0.3−4.1%, respectively. Conclusions The proposed method is a simple and cost‐effective method suitable for routine analyses and could be useful for biological monitoring of occupational exposure to MBOCA.