Sorahan Tom, Harrington J Malcolm
Institute of Occupational and Environmental Medicine, University of Birmingham, Edgbaston, Birmingham, UK.
Am J Ind Med. 2007 Aug;50(8):555-64. doi: 10.1002/ajim.20481.
Previously published analyses of excess lung cancer risks in UK carbon black production workers attracted no confident interpretation.
The mortality of a cohort of 1,147 male manual workers from five UK factories manufacturing carbon black was investigated for the period 1951-2004. All subjects were first employed in the period 1947-74 and were employed for 12 months or more. Limited work histories were available to calculate estimates of individual cumulative exposure to carbon black.
Based on serial rates for the general population of England and Wales, significantly elevated mortality was observed for lung cancer (Obs 67, SMR 146, P < 0.01) but not for all other causes combined (Obs 426, SMR 106). There was highly elevated lung cancer mortality at two of the plants (SMR 230, Obs 35) but no excess mortality at the other three plants combined (SMR 104, Obs 32). Analyses by period since leaving employment indicated elevated lung cancer risks were limited to those workers with some employment in the most recent 15 years. SMR analyses found an overall positive significant trend between lung cancer risks and cumulative carbon black exposure received in the most recent 15 years. Poisson regression analyses provided different results depending on which variables were adjusted for.
The findings suggest that carbon black, or chemicals associated with the production of carbon black, had an effect on later stages of lung cancer carcinogenesis at two of the plants but that no such effect was found at the other plants.
先前发表的关于英国炭黑生产工人肺癌额外风险的分析未得到可靠的解释。
对英国五家炭黑生产工厂的1147名男性体力劳动者队列在1951年至2004年期间的死亡率进行了调查。所有受试者均于1947年至1974年期间首次就业，且工作时间达12个月或更长。可获取的工作经历有限，用于计算个体炭黑累积暴露量的估计值。
根据英格兰和威尔士普通人群的系列死亡率，观察到肺癌死亡率显著升高（观察值67，标准化死亡比146，P<0.01），但其他所有原因导致的死亡率并未升高（观察值426，标准化死亡比106）。其中两家工厂的肺癌死亡率极高（标准化死亡比230，观察值35），但另外三家工厂合并后的死亡率并未升高（标准化死亡比104，观察值32）。按离职后的时间段进行分析表明，肺癌风险升高仅限于那些在最近15年中有过工作经历的工人。标准化死亡比分析发现，肺癌风险与最近15年中炭黑累积暴露量之间总体呈显著正相关趋势。泊松回归分析根据所调整的变量不同而得出不同结果。
研究结果表明，炭黑或与炭黑生产相关的化学物质在两家工厂对肺癌致癌作用的后期阶段产生了影响，但在其他工厂未发现此类影响。
