Moulin J J
Institut National de Recherche et de Sécurité (INRS) (French National Institute for Research and Safety) Service d'Epidemiologie (Department of Epidemiology), Vandoeuvre Les Nancy, France.
Scand J Work Environ Health. 1997 Apr;23(2):104-13. doi: 10.5271/sjweh.187.
A meta-analysis of epidemiologic studies was carried out on lung cancer risk among shipyard, mild steel, and stainless steel welders, and the role of asbestos exposure and smoking was considered.
The meta-analysis consisted of calculating combined relative risks (RR) and their variances through a logarithm transformation of published RR values and a weighing using the inverted variance of each RR.
The literature provided 18 case-referent and 31 cohort studies. The combined RR values were 1.38 [observed 1028, 95% confidence interval (95% CI) 1.29-1.48] for "all or unspecified welding categories", 1.30 (observed 305, 95% CI 1.14-1.48) for shipyard welders, and 1.35 (observed 173, 95% CI 1.15-1.58) for nonshipyard welders. Similar combined RR values (RR) were observed for mild steel welders (combined RR 1.50, observed 137, 95% CI 1.18-1.91) and stainless steel welders (combined RR 1.50 observed 114, 95% CI 1.10-2.05). No significant heterogeneity was discerned between studies of any welding or study design category. A marked healthy worker effect may also lead to an underestimation of the standardized mortality ratio for lung cancer among stainless steel welders. Furthermore, welders of any category are likely to be exposed to asbestos. Welders also seem to smoke more than the general male population, and therefore the hypothesis of tobacco overconsumption among welders could not be discarded.
A 30-40% increase in the RR of lung cancer among welders cannot be explained by hexavalent chromium and nickel exposure among stainless steel welders. The combination of the carcinogenic effects of asbestos exposure and smoking may account for part of the lung cancer excess observed.
对造船厂、低碳钢和不锈钢焊工患肺癌风险的流行病学研究进行荟萃分析，并考虑石棉暴露和吸烟的作用。
荟萃分析包括通过已发表相对危险度（RR）值的对数转换计算合并相对危险度及其方差，并使用每个RR的倒数方差进行加权。
文献提供了18项病例对照研究和31项队列研究。“所有或未明确分类的焊接类别”的合并RR值为1.38（观察到1028例，95%置信区间[95%CI]1.29 - 1.48），造船厂焊工为1.30（观察到305例，95%CI 1.14 - 1.48），非造船厂焊工为1.35（观察到173例，95%CI 1.15 - 1.58）。低碳钢焊工（合并RR 1.50，观察到137例，95%CI 1.18 - 1.91）和不锈钢焊工（合并RR 1.50，观察到114例，95%CI 1.10 - 2.05）观察到类似的合并RR值。在任何焊接或研究设计类别的研究之间未发现显著异质性。明显的健康工人效应也可能导致不锈钢焊工肺癌标准化死亡比的低估。此外，任何类别的焊工都可能接触石棉。焊工似乎也比一般男性人群吸烟更多，因此焊工烟草过度消费的假设不能被排除。
焊工患肺癌RR增加30 - 40%不能用不锈钢焊工接触六价铬和镍来解释。石棉暴露和吸烟的致癌作用结合可能是观察到的肺癌超额发病的部分原因。
