The Silicoat project: In vitro and in vivo toxicity screening of quartz varieties from ceramics industry and approaches for an effective quartz surface coating

Autor: Creutzenberg, Otto H., Reamon-Buettner, Stella Marie, Tillmann, Thomas, Hansen, Tanja, Garcia, M.J., Monfort, Eliseo, Bonvicini, Giuliana, Escrig, Alberto, Ziemann, Christina
Přispěvatelé: Publica
Jazyk: angličtina
Rok vydání: 2015
Popis: The IARC has classified respirable crystalline silica (RCS) as human carcinogens (category 1; 1997), however, acknowledging evident differences among RCS varieties. In the traditional ceramics industry, quartz containing materials are indispensable for the manufacturing process. The SILICOAT project thus aims at increasing workers' safety by developing cost-effective RCS coating technologies into ceramic processes to reduce quartz-specific toxic effects. As the first step 25 quartz-containing or -free raw materials were screened in vitro (primary rat alveolar macrophage) and in vivo (intratracheal instillation rat study) for their biological activity using highly active quartz DQ12 as positive control. Initial cytotoxicity screening experiments (LDH test using aluminum lactate as a quencher of quartz-specific effects), revealed no marked cytotoxic effect for all quartz-free (calcite, dolomite, alumina) and feldspar bulk samples and almost all wet milled materials. However, bulk samples exhibited variable quartz-related cytotoxic potential. Samples with the highest quartz content were further investigated on clastogenicity (comet assay) and pro-inflammatory CXCL2 gene expression (qRT-PCR). All quartzes and kaolins, but no clay mediated DNA damage and all materials induced CXCL2 gene expression. An in vivo validation study elicited lack of effect for clays and an initially retarded, but after 28 days progressive effect for quartzes (PMN, LDH). The most active quartz was used for promising covalent organosilane-based coating strategies. In conclusion, screening demonstrated gradually different quartz-specific or -independent biological activity of ceramic raw materials and indicated attenuation of quartz effects by wet milling with alumina balls. - Funded by the EU (FP7) under grant agreement n° 285787.0.
Databáze: OpenAIRE