Poole A, Brown R C, Rood A P
Br J Exp Pathol. 1986 Apr;67(2):289-96.
The in vitro activities of a highly carcinogenic potassium octatitanate fibre (Fybex) have been investigated. This material caused a low level of in vitro transformation in C3H10T1/2 cells and is thus more active in this assay than the UICC amphibole asbestos samples but less active than fibrous erionite. This ranking is in accord with carcinogenicity in vivo. However Fybex had no detectable activity in an assay for DNA damage based on the S1-nuclease sensitivity of the DNA from exposed cells. In that assay crocidolite asbestos was more active than either of the more carcinogenic dusts. It is suggested that the activities of amphibole asbestos in assays for genetic toxicity may depend on the production of free radicals via a catalytic reaction requiring the presence of transition elements which are either not present or only present at low concentrations in erionite or Fybex. This type of reaction may not be related to in vivo carcinogenicity. The action of fibrous dusts against macrophage-like cells, measured in this instance by the release of arachidonic acid, remains one of the best measures of biological activity.
对一种高致癌性的钛酸钾纤维（Fybex）的体外活性进行了研究。这种材料在C3H10T1/2细胞中引起了低水平的体外转化，因此在该检测中比国际抗癌联盟（UICC）的闪石石棉样品更具活性，但比纤维状毛沸石活性低。这种排序与体内致癌性一致。然而，在基于暴露细胞DNA的S1核酸酶敏感性的DNA损伤检测中，Fybex没有可检测到的活性。在该检测中，青石棉比两种致癌性更强的粉尘中的任何一种都更具活性。有人提出，闪石石棉在遗传毒性检测中的活性可能取决于通过催化反应产生自由基，这种催化反应需要过渡元素的存在，而在毛沸石或Fybex中这些过渡元素不存在或仅以低浓度存在。这种反应类型可能与体内致癌性无关。在这种情况下，通过花生四烯酸的释放来衡量纤维粉尘对巨噬细胞样细胞的作用，仍然是生物活性的最佳衡量指标之一。
