Goynes W R, Ingber B F, Palmgren M S
Environ Health Perspect. 1986 Apr;66:125-33. doi: 10.1289/ehp.8666125.
Specialized analytical methods are required for identification of components of agricultural dusts such as those generated in harvesting, transportation, storage, and processing of cotton, corn, and soybeans. The larger particles and trash components of the dusts can often be identified visually or with the aid of an optical microscope (OM). The respirable portion of the dust, that which causes lung dysfunction, retains few structural features for identification. Electron microscopy and X-ray microanalysis, together with special optical microscopical techniques, can be used to characterize these microdusts. Combination studies with scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis of cotton dusts have shown the presence of mineralogical particles probably of a soil origin and materials that can be associated with plant parts. Even in screened and filtered cotton dusts, fibrillar fragments are usually present due to their ability to penetrate openings the size of their diameters. The corn and soybean dusts studied were different from the cotton dust in that the large fibrillar component of the cotton dust was absent in the screened grain dusts. However, these dusts consisted of structurally unrecognizable particles that appeared similar to those found in cotton dust. In addition they contained many spheroid particles identified as starch. Dusts from all three sources were found to agglomerate into larger particles, some of which were still less than 10 micron. This agglomeration could confuse the instrumental measurement of dust particle size.
识别农业粉尘的成分需要专门的分析方法，比如棉花、玉米和大豆在收获、运输、储存及加工过程中产生的粉尘。粉尘中较大的颗粒和杂质成分通常可以通过肉眼或借助光学显微镜（OM）来识别。导致肺功能障碍的可吸入粉尘部分几乎没有可供识别的结构特征。电子显微镜和X射线微量分析，以及特殊的光学显微镜技术，可用于表征这些微尘。对棉花粉尘进行扫描电子显微镜（SEM）和能量色散X射线（EDX）分析的联合研究表明，存在可能源自土壤的矿物颗粒以及与植物部分相关的物质。即使是经过筛选和过滤的棉花粉尘，由于其纤维状碎片能够穿透直径与其大小相当的孔隙，通常也会存在。所研究的玉米和大豆粉尘与棉花粉尘不同，在筛选后的谷物粉尘中不存在棉花粉尘中那种大量的纤维状成分。然而，这些粉尘由结构上无法识别的颗粒组成，看起来与棉花粉尘中的颗粒相似。此外，它们还含有许多被鉴定为淀粉的球状颗粒。发现来自所有这三种来源的粉尘会团聚成更大的颗粒，其中一些颗粒仍小于10微米。这种团聚可能会使仪器对粉尘粒径的测量产生混淆。
