Ireland B, Collins J J, Buckley C F, Riordan S G
Monsanto Company, St. Louis, MO. 63167, USA.
Epidemiology. 1997 May;8(3):318-20. doi: 10.1097/00001648-199705000-00016.
We updated a cohort mortality study of 4,172 workers at a chemical plant to examine cancer mortality among workers exposed to low levels of benzene. Overall mortality [standardized mortality ratio (SMR) = 1.0; 95% confidence interval (CI) = 0.9-1.1] and cancer mortality (SMR = 1.0; 95% CI = 0.8-1.3) rates were at expected levels for production workers with benzene exposure. We observed elevated, albeit imprecise, rates of leukemia (SMR = 2.3; 95% CI = 0.7-5.3) and multiple myeloma (SMR = 2.3; 95% CI = 0.7-9.4) in this group of workers. The leukemias and multiple myelomas occurred predominantly among workers 20 or more years after first exposure. The leukemias were not restricted to acute myelogenous subtypes, and they occurred predominantly among workers hired before 1950 at exposure levels lower than previously reported. Leukemia (SMR = 1.3; 95% CI = 0.6-2.4) and multiple myeloma (SMR = 1.2; 95% CI = 0.3-2.9) rates were at expected levels among maintenance workers with intermittent high exposure to benzene. These findings provide evidence on both sides of the debate about whether low benzene exposure increases the risk of multiple myeloma and all types of leukemia.
我们对一家化工厂4172名工人的队列死亡率研究进行了更新，以调查低水平苯暴露工人中的癌症死亡率。对于有苯暴露的生产工人，总体死亡率[标准化死亡率比（SMR）=1.0；95%置信区间（CI）=0.9 - 1.1]和癌症死亡率（SMR = 1.0；95% CI = 0.8 - 1.3）处于预期水平。我们观察到该组工人中白血病（SMR = 2.3；95% CI = 0.7 - 5.3）和多发性骨髓瘤（SMR = 2.3；95% CI = 0.7 - 9.4）的发生率有所升高，尽管并不精确。白血病和多发性骨髓瘤主要发生在首次暴露20年或更长时间后的工人中。白血病并不局限于急性髓性亚型，且主要发生在1950年前受雇、暴露水平低于先前报告的工人中。在间歇性高暴露于苯的维修工人中，白血病（SMR = 1.3；95% CI = 0.6 - 2.4）和多发性骨髓瘤（SMR = 1.2；95% CI = 0.3 - 2.9）的发生率处于预期水平。这些发现为关于低苯暴露是否会增加多发性骨髓瘤和所有类型白血病风险的争论双方都提供了证据。
