Naturally Occurring Asbestos (NOA) on serpentinite outcrops are exposed to abiotic and biotic environmental forces which may affect their toxicity-relevant properties. Lichen colonization and deterioration were examined on monomineralic and polymineralic veins, containing asbestos (chrysotile, tremolite) and/or asbestiform minerals (antigorite, balangeroite, carlosturanite, diopside). The hyphal penetration of Candelariella vitellina within the different veins ranged from few hundreds of microns to several millimetres. The various NOA mineral species contacted by lichen hyphae were differently modified in their chemical composition. NOA were incubated in the laboratory with oxalic acid to mimic the dissolution process driven by lichen metabolites bearing acidic and chelating functions, typically pulvinic acid in the case of C. vitellina. The incubated fibres were chemically modified to the same extent of those colonized by C. vitellina in the field and were used to examine the effects of lichen deterioration on the toxicity-relevant release of Reactive Oxygen Species (ROS). Incongruent dissolution patterns observed in the cases of chrysotile-, chrysotile + balangeroite- and tremolite bearing veins were associated to a significant (even if not complete) inactivation of the surface. Conversely, the veins bearing minerals subjected to congruent dissolution (antigorite, diopside) maintained their reactivity. Lichen colonization may thus be associated to a bioattenuation process on some kinds of fibrous veins, but such effect cannot be generalized to all colonized NOA.

Lichen deterioration of asbestos and asbestiform minerals of serpentinite rocks in Western Alps

FAVERO LONGO, Sergio Enrico;TURCI, Francesco;FUBINI, Bice;CASTELLI, Daniele Carlo Cesare;PIERVITTORI, Rosanna
2013-01-01

Abstract

Naturally Occurring Asbestos (NOA) on serpentinite outcrops are exposed to abiotic and biotic environmental forces which may affect their toxicity-relevant properties. Lichen colonization and deterioration were examined on monomineralic and polymineralic veins, containing asbestos (chrysotile, tremolite) and/or asbestiform minerals (antigorite, balangeroite, carlosturanite, diopside). The hyphal penetration of Candelariella vitellina within the different veins ranged from few hundreds of microns to several millimetres. The various NOA mineral species contacted by lichen hyphae were differently modified in their chemical composition. NOA were incubated in the laboratory with oxalic acid to mimic the dissolution process driven by lichen metabolites bearing acidic and chelating functions, typically pulvinic acid in the case of C. vitellina. The incubated fibres were chemically modified to the same extent of those colonized by C. vitellina in the field and were used to examine the effects of lichen deterioration on the toxicity-relevant release of Reactive Oxygen Species (ROS). Incongruent dissolution patterns observed in the cases of chrysotile-, chrysotile + balangeroite- and tremolite bearing veins were associated to a significant (even if not complete) inactivation of the surface. Conversely, the veins bearing minerals subjected to congruent dissolution (antigorite, diopside) maintained their reactivity. Lichen colonization may thus be associated to a bioattenuation process on some kinds of fibrous veins, but such effect cannot be generalized to all colonized NOA.
2013
84
342
350
http://dx.doi.org/10.1016/j.ibiod.2012.07.018
S.E. Favero-Longo; F. Turci; B. Fubini; D. Castelli; R. Piervittori
File in questo prodotto:
File Dimensione Formato  
OK-858897_Lichen deterioration of asbestos.pdf

Open Access dal 02/11/2015

Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 669.95 kB
Formato Adobe PDF
669.95 kB Adobe PDF Visualizza/Apri
Favero et al., 2013 IBB.pdf

Accesso riservato

Tipo di file: PDF EDITORIALE
Dimensione 1.64 MB
Formato Adobe PDF
1.64 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/117842
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 17
  • ???jsp.display-item.citation.isi??? 15
social impact