Pacella,A., Andreozzi,G.B. and Fournier,J.(2010): Detailed crystal chemistry and iron topochemistry of asbestos occurring in its natural setting: A first step to understanding its chemical reactivity. Chemical Geology, 277, 197-206.

『天然環境での生成しているアスベストの詳細な結晶化学的性質と鉄トポ化学的性質：その化学的反応性を理解するための最初の一歩』

『Abstract
　Five samples of tremolite asbestos from Italy and USA were fully characterized by ICP-MS, SEM, EMPA, FT-IR, MS, XRPD, to correlate crystal chemistry with chemical reactivity. Iron topochemistry was investigated in detail, due to the role of Fe in the aetiology of respiratory inflammatory diseases. The Italian tremolite samples have different Fe contents (San Mango＞Ala di Stura＞Rufeno＞Castelluccio Superiore), and the USA sample from Maryland shows a value almost double that of the Italian samples. The bulk Fe3+/Fetot ratio was quantified by Mossbauer（oの頭に¨） spectroscopy, and the values obtained range from 6％ Fetot (San Mango tremolite) to 24％ Fetot (Mt. Rufeno tremolite). A possible site distribution of Fe was derived from combining chemical, spectroscopic (Mossbauer（oの頭に¨）) and structural (Rietveld refinement) data. For all samples Fe2+ was disordered over M(1), M(2) and M(3) sites, whereas Fe3+ was allocated to M(2). Production of HOo radical in the presence of hydrogen peroxide from the Italian samples is a measure of chemical reactivity, with the lowest value observed for the Castelluccio Superiore sample, and the highest value for the San Mango sample. Notably, HOo radical production is directly related to the Fe occupancy of the M(1) and M(2) octahedra, which are more exposed on the external surface of the fibers than M(3) octahedra and therefore have higher probability of being involved in surface reactions.

Keywords: Tremolite; Asbestos; Crystal chemistry; Iron topochemistry; Reactive oxygen species; Hydroxyl radical』

1. Introduction
2. Materials and analytical methods
　2.1. Materials
　2.2. Analytical methods
　　2.2.1. Scanning electron microscopy (SEM), electron microprobe analysis (EMPA) and inductively coupled plasma-mass spectrometry (ICP-MS)
　　2.2.2. 57Fe Mossbauer（oの頭に¨） spectroscopy (MS)
　　2.2.3. Fourier-transform infrared (FT-IR) spectroscopy
　　2.2.4. X-ray Powder Diffraction (XRPD)
　　2.2.5. Determination of HOo radicals by electron paramagnetic resonance (EPR) spectroscopy
3. Results
4. Discussion
　4.1. Asbestos reactivity: is iron content a proxy?
Acknowledgments
References

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