Towards a general model to predict theTowards a general model to predict the toxicity of mineral fibres? y f f
The perspective of the fibre
Prof. Alessandro Francesco GualtieriDipartimento di Scienze Chimiche e GeologicheDipartimento di Scienze Chimiche e Geologiche
Via Campi 103, 41125 Modena (Italy)
Why a model on the toxicity of mineral fibres?Th It li PRIN 2010 2011 t 2010MKHT9B 004 j t “I t tiThe Italian PRIN 2010‐2011 ‐ prot. 2010MKHT9B_004 project “Interaction between minerals and biosphere: consequences for environment and human health” is aimed at the systematic investigation of the crystal‐chemistry and bio‐
The perspective of the invader (fibre≡cause), not just the invaded
toxicity of the mineral fibres of social and economic importance.
(organism ≡effects)!
A biti l f l if i i l fib b d th i t ti lAmbitious goal of classifying mineral fibres based on their potential toxicity/pathogenicity.
Help to solve the chrysotile global ban litigation which is still an open issue:Carbone et al. (2007) “After 40 years of research on whether chrysotile does or does not cause mesothelioma, the issue is still unresolved and th t i t th ”the controversy is stronger than ever.”
Towards a general model to predict the toxicity of mineral fibres? Alessandro F. Gualtieri
Model of fibres pathogenicity/toxicityMacro‐parameter Label Parameter Related toxicity/pathogenicity factorMacro parameter Label Parameter y/p g y
Fibre size and morphometricparameters
1a Length/diameter/aspect ratio Frustrated phagocytosis/inflammatory burst
1b Equivalent aerodynamic diameter Airways deposition depth
1 t l h bit Airways deposition depthp
1c crystal habit Airways deposition depth
1d Density Airways deposition depth
1e Surface chemistry/area Airways deposition depth
Iron and toxic elements
2a Iron content and nuclearity Production of free radicals
2b surface vs. bulk iron Production of free radicals
2c Fe2+ vs. Fe3+ Production of free radicals
2d elements other than iron Various toxic bio‐chem reactions, ROS production …
Biodurability/ 3a biodurability (fibre dissolution rate) Frustrated phagocytosis/chronic inflammationCrystallinity inflammation
3b biodurability (rate of iron release) Production of free radicals
3c production of silica relicts during dissolution Production of free radicals
3d f l f i i l V i t i bi h ti ROS3d rate of release of active toxic elements Various toxic bio‐chem reactions, ROS production …
Surface charge 4a ξ Potential (surface chemical interaction) ROS production, various toxic bio‐chemreactions, interference with ER cross‐talk?
4b ξ Potential (fibers’ aggregation) Frustrated phagocytosis/chronic inflammation
Towards a general model to predict the toxicity of mineral fibres? Alessandro F. Gualtieri
The model: ironfibrous crystal habit→ partial phagocytosis and generation of ROS y p p g y g
(H2O2) +
available surface Fe2+, stable in the macrophage environment p g=
Production of highly reactive free hydroxyldi l Li id id DNA d
Fenton catalysis in the Haber‐Weiss cycle
radicals→ Lipid peroxidase + DNA damagey
H2O2 + LFe2+ → LFe3++ HO•+ HO‐
Sample Calculated chemical formula
h tilchrysotileUICC (Mg5.93Fe2+
0.04Al0.02Fe3+0.08)6.07Si4.03O10(OH)7.66
crocidolite (N C K ) (F 2+ F 3+ M ) (Si Al ) O (OH)crocidoliteUICC (Na1.96Ca0.03K0.01)2(Fe2+
2.34Fe3+2.05Mg0.52)4.91(Si7.84Al0.02)7.86O21.36(OH)2.64
Erionite-Na Nevada Fe3+
<0.1(Na5.35K2.19Ca0.15Mg0.11Ti0.05)7.85(Si28.01Al7.90)35.91O72·28.13H2ONevada
Towards a general model to predict the toxicity of mineral fibres? Alessandro F. Gualtieri
Pollastri, S., D’Acapito, F., Trapananti, A., Colantoni, I., Andreozzi, G.B., Gualtieri, A.F. (2015) J. Haz. Mat., 298, 282‐293.
The model: ironThe key role of iron in erionite?e ey o e o o e o te?
Towards a general model to predict the toxicity of mineral fibres? Alessandro F. Gualtieri
Gualtieri, A.F., Bursi Gandolfi, N., Pollastri, S., Pollok, K., Langenhorst, F. (2016) SCI. REP., submitted.
The model: toxic elements other than iron
Towards a general model to predict the toxicity of mineral fibres? Alessandro F. Gualtieri
Bloise, A., Barca, D., Gualtieri, A.F., Pollastri, S., Belluso E. (2016) Environmental Pollution, 216, 314‐323.
The model: toxic elements other than iron
Towards a general model to predict the toxicity of mineral fibres? Alessandro F. Gualtieri
Bloise, A., Barca, D., Gualtieri, A.F., Pollastri, S., Belluso E. (2016) Environmental Pollution, 216, 314‐323.
Final remarks/work in progress• Development of the math beyond theDevelopment of the math beyond the
model in progress
• We live in a world plenty of fibres• We live in a world plenty of fibres
requiring a general model to predict a
priori the toxicity potential of mineral
fibres, identify their occurrences, and
plan a risk assessment analysis for the
population to reduce exposures to NOA!population to reduce exposures to NOA!
• Prediction=prevention: no more
situations like the turkish erionite and
the Italian Biancavilla fluoro‐edenite
Towards a general model to predict the toxicity of mineral fibres? Alessandro F. Gualtieri
case!
Final remarks/announcementThe State of the Art on mineral fibers and toxicity model discussed atThe State of the Art on mineral fibers and toxicity model discussed at
Fibers.unimore.it
and published in the EMU NOTES volume to be delivered in 2017!and published in the EMU NOTES volume to be delivered in 2017!
Thanks to all the research units of the PRIN2011 project and p jthank you all for the attention!
Towards a general model to predict the toxicity of mineral fibres? Alessandro F. Gualtieri
