This study aims at disclosing the morphological and chemical-structural modifications that occur during thermal degradation of amphibole asbestos. Low-iron tremolite and iron-rich crocidolite will be heated at temperatures ranging from r.t. to 1200°C. Pristine and heated samples will be analysed by X-ray powder diffraction, FESEM and TEM. The effects of the thermal modifications on toxicologically relevant asbestos reactivity will be evaluated by quantifying carbon- and oxygen-centred, namely ¿OH), radicals. The expected outcomes will be useful for asbestos inertization studies as we expect that morphology and surface reactivity, beyond crystallinity, should be considered when proving that a thermally inactivated asbestos-containing material is safe.
This is the first attempt to verify the presence of residual chemical reactivity on thermally treated asbestos. The results of this work will be useful in the evaluation on the safety of the thermally decomposed ACM. More generally, this study will contribute to the ongoing debate of which altered/weathered naturally occurring asbestos (NOA) and non-asbestos mineral fibres may pose a risk to human health (Harper M., 2008; Favero-Longo et al., 2009; Bloise et al., 2017a;).