Gylestam Daniel, Gustavsson Marcus, Karlsson Daniel, Dalene Marianne, Skarping Gunnar
Work Environment Chemistry, Stockholm University, Hässleholm, Sweden;
Ann Occup Hyg. 2014 Apr;58(3):340-54. doi: 10.1093/annhyg/met067. Epub 2013 Dec 26.
An advanced design of a denuder impactor (DI) sampler has been developed for characterization of possible airborne isocyanate exposure in different particle size fractions. The sampler is equipped with 12 different parallel denuder tubes, 4 impaction stages with the cut-off values (d50) of: 9.5, 4, 2.5 and 1 µm, and an end filter that collects particles < 1 µm. All collecting parts were impregnated with di-n-butylamine DBA as the reagent in a mixture with acetic acid. The performance of the DI sampler was studied on a standard atmosphere containing gas and particulate isocyanates. The isocyanate atmosphere was generated by liquid permeation of 2,4-, 2,6-Toluene Diisocyanate (TDI), 1,6-Hexamethylene Diisocyanate (HDI) and Isophorone Diisocyanate (IPDI). 4,4'-Methylene Diphenyl Diisocyanate (MDI) particles were generated by heating of technical MDI and condensing the mixture of gas and particle-borne MDI in an atmosphere containing mixed salt particles. The study was performed in a 0.85 m3 environmental chamber with stainless steel walls. With the advancement of the DI sampler it is now possible to collect isocyanate particle samples for up to 320 min. The performance of the DI sampler is essentially unaffected by the humidity. The DI sampler and the ASSET EZ4-NCO sampler (Sigma-Aldrich/Supelco, Bellefonte, PA, USA) gave similar results. Sample losses within the DI sampler are low. In the environmental chamber it was observed that the particle distribution may be affected by the humidity and ageing. A scanning mobility particle sizer (SMPS) was used to separate a flow of selected fractions containing MDI particles from mixed MDI and salt particles. The particle-size distribution had a maximum at about 300 nm, but later in the environmental chamber 1 µm dominated. The distribution was very different as compared to with only NaCl or MDI present. The biological relevance for studying isocyanate nano particles is significant as these have the possibility to reach the lower airways where allergic reactions may occur. SMPS and isocyanate air sampling can be used for the investigation of isocyanate nano particles.
已开发出一种先进的去溶蚀冲击器（DI）采样器，用于表征不同粒径分数下可能的空气中异氰酸酯暴露情况。该采样器配备有12根不同的平行去溶蚀管、4个冲击阶段，其截止值（d50）分别为：9.5、4、2.5和1微米，以及一个收集小于1微米颗粒的末端过滤器。所有收集部件都浸渍有二正丁胺（DBA）作为试剂，并与乙酸混合。在含有气态和颗粒态异氰酸酯的标准大气中研究了DI采样器的性能。异氰酸酯气氛通过2,4-、2,6-甲苯二异氰酸酯（TDI）、1,6-六亚甲基二异氰酸酯（HDI）和异佛尔酮二异氰酸酯（IPDI）的液体渗透产生。4,4'-二苯基甲烷二异氰酸酯（MDI）颗粒通过加热工业MDI并在含有混合盐颗粒的气氛中冷凝气态和颗粒态MDI的混合物来产生。该研究在一个0.85立方米、壁为不锈钢的环境舱中进行。随着DI采样器的改进，现在可以采集长达320分钟的异氰酸酯颗粒样品。DI采样器的性能基本上不受湿度影响。DI采样器和ASSET EZ4-NCO采样器（美国宾夕法尼亚州贝勒方特的西格玛-奥德里奇/苏珀科公司）给出了相似的结果。DI采样器内的样品损失很低。在环境舱中观察到颗粒分布可能受湿度和老化影响。使用扫描迁移率粒径分析仪（SMPS）从混合的MDI和盐颗粒中分离出包含MDI颗粒的选定粒径分数的气流。粒径分布在约300纳米处有一个最大值，但在环境舱中稍后1微米的颗粒占主导。与仅存在氯化钠或MDI时相比，分布非常不同。研究异氰酸酯纳米颗粒的生物学意义重大，因为这些颗粒有可能到达下呼吸道，在那里可能发生过敏反应。SMPS和异氰酸酯空气采样可用于研究异氰酸酯纳米颗粒。
