Glass D C, Gray C N, Adams G G, Manuell R W, Bisby J A
Department of Epidemiology and Preventive Medicine, Monash University, Prahran, Victoria, Australia.
Toxicol Ind Health. 2001 May;17(4):113-27. doi: 10.1191/0748233701th099oa.
A nested case-control study was undertaken to investigate whether an excess of lympho-haematopoietic cancers in the Australian petroleum industry was associated with benzene exposure. The benzene exposures of the cases and controls were estimated using a quantitative algorithm based largely on exposures measured in the Australian petroleum industry. The algorithm was used to estimate, for each subject, the benzene exposure in parts per million (ppm) for each job held in the industry, and the cumulative exposure in ppm years. Because of the critical importance of the exposure assessment in this design of epidemiological study, particular attention was paid to the reliability of the inputs to the algorithm. The inputs [base estimates (BEs) of exposure and technology-specific exposure modifiers (EMs)] were compared to data from other sources including the occupational hygiene literature. Where such comparison data were available, they were generally found to confirm the values used in the algorithm, although four input values were changed as a result of the validation exercise. The integrity of the task-based algorithm was validated by employing it to calculate the exposures of the tanker drivers in the study and comparing these with measured daily exposure for tanker drivers in the Australian petroleum industry and exposure values found in the occupational hygiene literature. After adjustment for the mix of products carried by the Australian tanker drivers, the estimates from the algorithm were found to be comparable to the measured and literature values. This exercise provided evidence that the exposure assessment for the epidemiological study was reliable and that the results of the study can be used as the basis for evaluating the relationship between exposure to benzene and the risk of lympho-haematopoietic cancer.
开展了一项巢式病例对照研究，以调查澳大利亚石油行业淋巴造血系统癌症过多是否与接触苯有关。病例组和对照组的苯接触量是使用一种定量算法估算的，该算法主要基于澳大利亚石油行业测量的接触量。该算法用于为每位受试者估算其在该行业担任的每项工作的百万分之一（ppm）苯接触量，以及以ppm年为单位的累积接触量。由于接触评估在这种流行病学研究设计中至关重要，因此特别关注算法输入数据的可靠性。将输入数据[接触量的基本估计值（BEs）和特定技术的接触修正因子（EMs）]与包括职业卫生文献在内的其他来源的数据进行了比较。在有此类比较数据的情况下，尽管有四个输入值因验证工作而发生了变化，但通常发现这些数据证实了算法中使用的值。通过使用基于任务的算法计算研究中油罐车司机的接触量，并将其与澳大利亚石油行业油罐车司机的每日实测接触量以及职业卫生文献中发现的接触值进行比较，验证了该算法的完整性。在对澳大利亚油罐车司机所运输产品的混合情况进行调整后，发现算法的估计值与实测值和文献值具有可比性。这项工作提供了证据，表明该流行病学研究的接触评估是可靠的，并且该研究结果可作为评估苯接触与淋巴造血系统癌症风险之间关系的基础。
