Gries Wolfgang, Küpper Katja, Leng Gabriele
Health Protection, Institute of Biomonitoring, Currenta GmbH & Co. OHG, 51368, Leverkusen, Germany,
Anal Bioanal Chem. 2015 May;407(12):3417-23. doi: 10.1007/s00216-015-8533-5. Epub 2015 Feb 21.
2-Mercaptobenzothiazole (MBT) is one of the most important vulcanization accelerators in the industrial production of rubber, especially car tires. Given its wide use in household articles and industrial rubber products it has a high potential to migrate into the environment. Humans can be exposed by dermal, oral, or inhalative routes. Incorporated MBT is excreted in urine, mainly as conjugates to glucuronide, sulfate, and mercapturic acid. On the basis of these facts MBT has been selected as a substance of high interest in the large scale 10-year German project on human biomonitoring (HBM); a cooperation between the German Federal Ministry for the Environment (BMUB) and the German Chemical Industry Association (VCI) with the objective of developing new analytical methods for relevant chemicals. The presented method was developed to determine MBT in human urine to reliably investigate the internal human MBT dose. Total MBT is measured after enzymatic hydrolysis followed by application of high-pressure liquid chromatography tandem mass spectrometry (HPLC-MS-MS) in positive-electrospray-ionization mode (ESI+) using isotope-dilution quantification. High sample throughput could be obtained by use of the column-switching technique. Optimization yielded an analytical method with a low and reproducible limit of detection (LOD) of 0.4 μg L(-1) and a limit of quantification (LOQ) of 1 μg L(-1), and low relative standard deviations in the range 1.6-5.8 %. A small biomonitoring study covering unexposed humans and occupationally exposed workers was performed to establish the feasibility and reliability of the method. MBT was found in only one urine sample from the unexposed humans, at a value of 10.8 μg MBT per liter, whereas it was found in all samples from the tested workers at values of up to 6210 μg MBT per liter.
2-巯基苯并噻唑（MBT）是橡胶工业生产中，尤其是汽车轮胎生产中最重要的硫化促进剂之一。鉴于其在家庭用品和工业橡胶制品中的广泛应用，它极有可能迁移到环境中。人类可通过皮肤、口腔或吸入途径接触到MBT。摄入体内的MBT主要以与葡萄糖醛酸、硫酸盐和巯基尿酸结合物的形式经尿液排出。基于这些事实，MBT被选为德国一项为期10年的大规模人体生物监测（HBM）项目中的重点关注物质；该项目由德国联邦环境部（BMUB）和德国化学工业协会（VCI）合作开展，旨在开发针对相关化学品的新分析方法。所提出的方法是为测定人尿中的MBT而开发的，以便可靠地研究人体内部MBT剂量。在酶促水解后，采用正电喷雾电离模式（ESI+）的高压液相色谱串联质谱法（HPLC-MS-MS），通过同位素稀释定量法测定总MBT。使用柱切换技术可实现高样品通量。经过优化，得到了一种分析方法，其检测限（LOD）低且可重复，为0.4 μg L⁻¹，定量限（LOQ）为1 μg L⁻¹，相对标准偏差低，在1.6 - 5.8%范围内。开展了一项小型生物监测研究，涵盖未接触者和职业接触工人，以确定该方法的可行性和可靠性。在未接触者的尿液样本中仅一份检测到MBT，浓度为每升10.8 μg MBT，而在所有受试工人的样本中均检测到MBT，浓度高达每升6210 μg MBT。
