Rödelsperger K, Woitowitz H J
Institute and Outpatient Clinic of Occupational and Social Medicine, Justus-Liebig-University, Giessen, Germany.
Ann Occup Hyg. 1995 Oct;39(5):715-25.
The excess risk of tumours exposed to asbestos were previously compared with the results of rat inhalation experiments. It could be demonstrated that humans at the workplace suffer from a tumour risk at fibre concentrations which are 300 times lower than those needed in the rat inhalation model to produce the same risk. However, the estimation of human risk was based on the study of workers at a chrysotile textile factory, whereas animal experimental results were related to exposure to amphiboles. Since for this comparison the risk of cancer due to exposure to amosite or crocidolite fibres at the workplace is of interest, quantitative exposure-response relationships for lung cancer and mesothelioma for the white workforce of South African amosite and crocidolite mines were discussed. On comparing the risk of lung cancer in this study with the risk of lung cancer for chrysotile textile workers, it can be concluded, that the risk of lung cancer and mesothelioma from crocidolite and amosite was higher than in the chrysotile textile factory. It could be also demonstrated, on the basis of a study of the lung burden of mesothelioma cases and of controls, that a significantly increased odds ratio of about 5 was established at amphibole concentrations of between 0.1 and 0.2 f micrograms-1 dry lung (WHO fibres longer than 5 microns from TEM analysis). On the other hand, carcinogenic response was observed at a fibre concentration 6000 times higher in animal inhalation experiments with crocidolite asbestos (SEM analysis of WHO fibres). As a result of these findings, it has been concluded that inhalation studies in rats are not sufficiently sensitive for the detection of hazards and risks to humans exposed to man-made fibres.
先前曾将接触石棉的肿瘤额外风险与大鼠吸入实验结果进行比较。结果表明，工作场所的人类在纤维浓度比大鼠吸入模型中产生相同风险所需浓度低300倍的情况下，仍面临肿瘤风险。然而，对人类风险的估计是基于对温石棉纺织厂工人的研究，而动物实验结果则与接触闪石有关。由于此次比较涉及工作场所接触铁石棉或青石棉纤维导致的癌症风险，因此讨论了南非铁石棉和青石棉矿白人劳动力患肺癌和间皮瘤的定量暴露-反应关系。将本研究中肺癌风险与温石棉纺织工人的肺癌风险进行比较后可以得出结论，青石棉和铁石棉导致的肺癌和间皮瘤风险高于温石棉纺织厂。基于对间皮瘤病例和对照组肺部负荷的研究还可以证明，在闪石浓度为0.1至0.2 f微克-1干肺（根据透射电镜分析，世界卫生组织定义的长度超过5微米的纤维）时，优势比显著增加约5倍。另一方面，在青石棉石棉的动物吸入实验中，在纤维浓度高出6000倍时观察到致癌反应（根据世界卫生组织纤维的扫描电镜分析）。基于这些发现，得出的结论是，大鼠吸入研究对检测接触人造纤维的人类所面临的危害和风险不够敏感。
