Nieuwenhuijsen M J, Noderer K S, Schenker M B, Vallyathan V, Olenchock S
Imperial College of Science, Technology and Medicine, London, U.K.
Ann Occup Hyg. 1999 Jan;43(1):35-42.
The aim of this study was to measure personal exposure to dust, endotoxin and crystalline silica during various agricultural operations in California over a period of one year.
Ten farms were randomly selected in Yolo and Solano counties and workers were invited to wear personal sampling equipment to measure inhalable and respirable dust levels during various operations. The samples were analysed for endotoxin using the Limulus Amebocyte Lysate assay and crystalline silica content using X-ray diffraction. In total 142 inhalable samples and 144 respirable samples were collected.
The measurements showed considerable difference in exposure levels between various operations, in particular for the inhalable fraction of the dust and the endotoxin. Machine harvesting of tree crops (Geometric mean (GM) = 45.1 mg/m3) and vegetables (GM = 7.9 mg/m3), and cleaning of poultry houses (GM = 6.7 mg/m3) showed the highest inhalable dust levels. Cleaning of poultry houses also showed the highest inhalable endotoxin levels (GM = 1861 EU/m3). Respirable dust levels were generally low, except for machine harvesting of tree crops (GM = 2.8 mg/m3) and vegetables (GM = 0.9 mg/m3). Respirable endotoxin levels were also low. For the inhalable dust fraction, levels were reduced considerably when an enclosed cabin was present. The percentage of crystalline silica was overall higher in the respirable dust samples than the inhalable dust samples.
Considerable differences exist in personal exposure levels to dust, endotoxin and crystalline silica during various agricultural operations in California agriculture with some operations showing very high levels.
本研究的目的是在一年时间内，测量加利福尼亚州各种农业作业过程中个人接触粉尘、内毒素和结晶二氧化硅的情况。
在约洛县和索拉诺县随机选择了10个农场，邀请工人佩戴个人采样设备，以测量各种作业过程中可吸入和可呼吸粉尘水平。使用鲎试剂法分析样品中的内毒素，使用X射线衍射分析结晶二氧化硅含量。总共收集了142个可吸入样品和144个可呼吸样品。
测量结果显示，不同作业之间的接触水平存在显著差异，特别是对于粉尘的可吸入部分和内毒素。果树作物（几何均值（GM）= 45.1毫克/立方米）和蔬菜的机械收割（GM = 7.9毫克/立方米），以及禽舍清洁（GM = 6.7毫克/立方米）显示出最高的可吸入粉尘水平。禽舍清洁也显示出最高的可吸入内毒素水平（GM = 1861 EU/立方米）。除了果树作物（GM = 2.8毫克/立方米）和蔬菜的机械收割（GM = 0.9毫克/立方米）外，可呼吸粉尘水平一般较低。可呼吸内毒素水平也较低。对于可吸入粉尘部分，当有封闭驾驶舱时，水平会显著降低。可呼吸粉尘样品中结晶二氧化硅的百分比总体上高于可吸入粉尘样品。
加利福尼亚州农业的各种农业作业过程中，个人接触粉尘、内毒素和结晶二氧化硅的水平存在显著差异，有些作业显示出非常高的水平。
