EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

New insights into the cytotoxicity of mineral fibres: A combined time-lapse video microscopy and in vitro assays study of chrysotile, crocidolite, and erionite fibres

Dario Di Giuseppe1, Sonia Scarfì2,3, Andrea Alessandrini4,5, Anna Maria Bassi3,6, Serena Mirata2,3, Vanessa Almonti3,6, Gregorio Ragazzini4,5, Andrea Mescola5, Monica Filaferro7, Rossella Avallone8, Giovanni Vitale8, Valentina Scognamiglio1, and Alessandro Gualtieri1
Dario Di Giuseppe et al.
  • 1University of Modena and Reggio Emilia, Department of Chemical and Geological Sciences, Modena, Italy (;;
  • 2Department of Earth, Environment and Life Sciences, University of Genoa, Italy (
  • 3Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research, Italy (;
  • 4Department of Physics, Informatics and Mathematics, University of Modena and Reggio Emilia, Italy (; )
  • 5CNR-Nanoscience Institute-S3, Italy (
  • 6Department of Experimental Medicine, University of Genoa, Italy (
  • 7Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Italy (
  • 8Department of Life Sciences, University of Modena and Reggio Emilia, Italy (;

Although in the last 30 years mineral fibres have been the subject of intensive toxicological studies, the actual mechanisms by which mineral fibres exert cytotoxic activity are not fully understood. In this scenario, our work focuses on the monitoring of the very early steps of the interaction between chrysotile, crocidolite and erionite fibres (classified as carcinogenic by the International Agency for Research on Cancer) and macrophages using time-lapse video microscopy coupled with in vitro assays (i.e. LDH cytotoxicity, MTT viability, ROS generation and annexin-FITC/PI apoptosis). All tests were performed on the THP-1 cell line, differentiated into M0 macrophages (M0-THP-1), after acute exposure (8 h) to 25 μg/mL of mineral fibres. Erionite fibres exhibit early toxicity effects while the cytotoxicity induced by chrysotile and crocidolite fibres occurs with a slight delay (ca. 2 h). In concert with literature data, the toxicity of chrysotile and crocidolite is linked to their ability to stimulate Reactive Oxygen Species (ROS) production. ROS are generated by M0-THP-1 cells as a result of frustrated phagocytosis induced by the long asbestos fibres, or produced by asbestos through the redox-active Fe on the fibre surface and metals released into the cell medium as a consequence of the partial dissolution of the fibres. Erionite fibres are able to induce an intracellular ROS increase but this contribution is significantly lower than both crocidolite and chrysotile stimuli. In the short period, crocidolite and chrysotile trigger significant apoptotic phenomena in M0-THP-1 cells while fibrous erionite is associated with early cytotoxicity and probably necrotic-like effect. Because the erionite fibres are short in length, frustrated phagocytosis plays a limited role in the acute toxicity of this fibre. Investigations focused on the intracellular concentrations of Na+ and Ca2+ as a result of cell-fibre interaction suggest an alternative mechanism by which fibrous erionite may induces cell injury and cell death. During phagocytosis erionite fibres quick exchange their extra-framework Na+ with the ions present in the cytosol of M0-THP-1 cells leading to the dysregulation of ionic homeostasis, cell swelling and cell lysis. At the same time, engulfed erionite fibres can reduce the level of cytosolic Ca2+ and interfere with endoplasmic reticulum-mitochondria crosstalk causing a delay in M0-THP-1 induction of apoptosis.

How to cite: Di Giuseppe, D., Scarfì, S., Alessandrini, A., Bassi, A. M., Mirata, S., Almonti, V., Ragazzini, G., Mescola, A., Filaferro, M., Avallone, R., Vitale, G., Scognamiglio, V., and Gualtieri, A.: New insights into the cytotoxicity of mineral fibres: A combined time-lapse video microscopy and in vitro assays study of chrysotile, crocidolite, and erionite fibres, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-836,, 2022.