Brouwer D H, Hoogendoorn L, Bos P M, Boogaard P J, van Hemmen J J
TNO Nutrition and Food Research Institute, Division of Toxicology, Zeist, The Netherlands.
Occup Environ Med. 1998 Dec;55(12):805-11. doi: 10.1136/oem.55.12.805.
To evaluate two different techniques for assessing dermal exposure to 4,4'-methylene dianiline (MDA) in a field study. The results were used to test the applicability of a recently proposed quantitative dermal occupational exposure limit (DOEL) for MDA in a workplace scenario.
For two consecutive weeks six workers were monitored for exposure to MDA in a factory that made glass fibre reinforced resin pipes. Dermal exposure of the hands and forearms was assessed during week 1 by a surrogate skin technique (cotton monitoring gloves) and during week 2 by a removal technique (hand wash). As well as the dermal exposure sampling, biological monitoring, measurement of MDA excretion in urine over 24 hours, occurred during week 2. Surface contamination of the workplace and equipment was monitored qualitatively by colorimetric wipe samples.
Geometric means of daily exposure ranged from 81-1762 micrograms MDA for glove monitoring and from 84-1783 micrograms MDA for hand washes. No significant differences, except for one worker, were found between exposure of the hands in weeks 1 and 2. Significant differences between the mean daily exposure of the hands (for both weeks and sampling methods) were found for all workers. The results of the colorimetric wipe samples indicated a general contamination of the workplace and equipment. Excretion of MDA in 24 hour urine samples ranged from 8 to 249 micrograms MDA, whereas cumulative MDA excretion over a week ranged from 82 to 717 micrograms MDA. Cumulative hand wash and MDA excretion results over a week showed a high correlation (R2 = 0.94). The highest actual daily dermal exposure found seemed to be about 4 mg (hand wash worker A on day 4), about 25% of the external DOEL. Testing of compliance by means of a biological limit value (BLV) led to similar results for the same worker. It is concluded that both dermal exposure monitoring methods were applicable and showed a compatible performance in the present exposure scenario, where the exposure relevant to dermal absorption is considered mainly restricted to hands. The concept for a DOEL seemed to be relevant and applicable for compliance testing and health surveillance in the situation under investigation.
在一项现场研究中评估两种不同的技术，以测定皮肤对4,4'-亚甲基二苯胺（MDA）的接触情况。研究结果用于测试最近提出的MDA定量皮肤职业接触限值（DOEL）在工作场所场景中的适用性。
连续两周对一家制造玻璃纤维增强树脂管的工厂中的6名工人进行MDA接触监测。第1周通过替代皮肤技术（棉质监测手套）评估手部和前臂的皮肤接触情况，第2周通过去除技术（洗手）进行评估。在第2周，除了进行皮肤接触采样外，还进行了生物监测，即测量24小时尿液中MDA的排泄量。通过比色擦拭样本对工作场所和设备的表面污染进行定性监测。
手套监测的每日接触几何均值为81 - 1762微克MDA，洗手的每日接触几何均值为84 - 1783微克MDA。除一名工人外，第1周和第2周手部接触情况无显著差异。所有工人双手的平均每日接触量（两周和两种采样方法）之间存在显著差异。比色擦拭样本结果表明工作场所和设备普遍受到污染。24小时尿液样本中MDA排泄量为8 - 249微克MDA，而一周内MDA累积排泄量为82 - 717微克MDA。一周内洗手累积量与MDA排泄量结果显示出高度相关性（R2 = 0.94）。发现的最高实际每日皮肤接触量似乎约为4毫克（第4天洗手的工人A），约为外部DOEL的25%。通过生物限值（BLV）进行合规性测试，该工人得到了类似结果。结论是，在当前的接触场景中，两种皮肤接触监测方法均适用且表现出一致的性能，在该场景中与皮肤吸收相关的接触主要限于手部。DOEL的概念似乎与所研究情况下的合规性测试和健康监测相关且适用。
