Fishbeck W A, Townsend J C, Swank M G
J Occup Med. 1978 Aug;20(8):539-42. doi: 10.1097/00043764-197808000-00005.
All ten employees have a history of exposure to benzene which exceeded a 25 ppm, eight-hour TWA for several years. For five of these employees this exposure level started over 20 years ago. One employee's high exposure level started over 35 years ago. All ten employees had their initial high exposure to benzene more than 16 years ago. At one period (late 1963 and early 1964) all ten employees had alterations in their peripheral blood studies, evidenced by an increase in MCV. Some of the employees had slight reduction of hemoglobin levels. No other significant blood or bone marrow abnormalities were evident. A mortality study, for the years 1940 to 1973, of 594 employees chronically exposed to benzene at the Midland, Mich., Dow location has recently been accepted for publication. This study was followed by a morbidity study of 282 employees, which were a subset of the employees in the mortality study. The morbidity study was based on health data obtained between 1967 and 1974. The ten employees described in this article were included in both the mortality study population of 594 employees and the morbidity study of the 282 employees.
所有十名员工都有苯暴露史，其多年来的八小时时间加权平均浓度超过了25 ppm。其中五名员工的这种暴露水平始于20多年前。一名员工的高暴露水平始于35多年前。所有十名员工在16多年前首次有高浓度苯暴露。在一个时期（1963年末和1964年初），所有十名员工的外周血研究出现改变，表现为平均红细胞体积增加。一些员工的血红蛋白水平略有降低。未发现其他明显的血液或骨髓异常。一项针对1940年至1973年期间在密歇根州米德兰陶氏工厂长期接触苯的594名员工的死亡率研究最近已被接受发表。该研究之后是对282名员工的发病率研究，这些员工是死亡率研究中员工的一个子集。发病率研究基于1967年至1974年期间获得的健康数据。本文所述的十名员工既包括在594名员工的死亡率研究人群中，也包括在282名员工的发病率研究中。
