Giacobbe Carlotta, Moliterni Anna, Di Giuseppe Dario, Malferrari Daniele, Wright Jonathan P, Mattioli Michele, Raneri Simona, Giannini Cinzia, Fornasini Laura, Mugnaioli Enrico, Ballirano Paolo, Gualtieri Alessandro F
European Synchrotron Radiation Facility (ESRF), 71 avenue des Martyrs, Grenoble 38000, France.
Institute of Crystallography-CNR, Via Amendola 122/o, Bari 70126, Italy.
IUCrJ. 2023 Jul 1;10(Pt 4):397-410. doi: 10.1107/S2052252523003500.
Erionite is a non-asbestos fibrous zeolite classified by the International Agency for Research on Cancer (IARC) as a Group 1 carcinogen and is considered today similar to or even more carcinogenic than the six regulated asbestos minerals. Exposure to fibrous erionite has been unequivocally linked to cases of malignant mesothelioma (MM) and this killer fibre is assumed to be directly responsible for more than 50% of all deaths in the population of the villages of Karain and Tuzköy in central Anatolia (Turkey). Erionite usually occurs in bundles of thin fibres and very rarely as single acicular or needle-like fibres. For this reason, a crystal structure of this fibre has not been attempted to date although an accurate characterization of its crystal structure is of paramount importance for our understanding of the toxicity and carcinogenicity. In this work, we report on a combined approach of microscopic (SEM, TEM, electron diffraction), spectroscopic (micro-Raman) and chemical techniques with synchrotron nano-single-crystal diffraction that allowed us to obtain the first reliable ab initio crystal structure of this killer zeolite. The refined structure showed regular T-O distances (in the range 1.61-1.65 Å) and extra-framework content in line with the chemical formula (KCa.MgNaBa)[SiAl]O·28.3HO. The synchrotron nano-diffraction data combined with three-dimensional electron diffraction (3DED) allowed us to unequivocally rule out the presence of offretite. These results are of paramount importance for understanding the mechanisms by which erionite induces toxic damage and for confirming the physical similarities with asbestos fibres.
毛沸石是一种非石棉纤维沸石，被国际癌症研究机构（IARC）列为1类致癌物，如今被认为与六种受管制的石棉矿物具有相似甚至更强的致癌性。接触纤维状毛沸石已明确与恶性间皮瘤（MM）病例相关，这种致命纤维被认为是土耳其安纳托利亚中部卡兰和图兹科伊村超过50%人口死亡的直接原因。毛沸石通常以细纤维束的形式出现，很少以单根针状或线状纤维的形式出现。因此，尽管准确表征其晶体结构对于我们理解其毒性和致癌性至关重要，但迄今为止尚未尝试确定这种纤维的晶体结构。在这项工作中，我们报告了一种结合微观（扫描电子显微镜、透射电子显微镜、电子衍射）、光谱（显微拉曼光谱）和化学技术以及同步加速器纳米单晶衍射的方法，使我们能够获得这种致命沸石的首个可靠的从头算晶体结构。精修后的结构显示出规则的T - O距离（在1.61 - 1.65 Å范围内）以及与化学式（KCa.MgNaBa）[SiAl]O·28.3HO相符的骨架外成分。同步加速器纳米衍射数据与三维电子衍射（3DED）相结合，使我们能够明确排除菱钾沸石的存在。这些结果对于理解毛沸石诱导毒性损伤的机制以及确认与石棉纤维的物理相似性至关重要。
