title: In vitro toxicological assessment of clays for their use in food packaging applications.
abstract: Montmorillonite based clays have a wide range of applications that are going to contribute to increase human exposure to these materials. One of the most promising uses of clays is the development of reinforced food contact materials that results in nanocomposites with improved barrier properties. Different organoclays have been developed introducing modifiers in the natural clay which is commercially available. However, the toxicological aspects of these materials have been scarcely studied so far. In the present study, the cytotoxic effects of a non-modified clay (Cloisite Na+) and an organoclay (Cloisite 30B) have been investigated in the hepatic cell line HepG2. Only Cloisite 30B showed cytotoxicity. In order to elucidate the toxic mechanisms underlying these effects, apoptosis, inflammation, oxidative stress and genotoxicity biomarkers were assayed. Moreover, a morphology study with light and electron microscopy was performed. Results showed genotoxic effects and glutathione decrease. The most relevant ultraestructural alterations observed were mitochondrial degeneration, dilated endomembrane systems, heterophagosomes formation, fat droplets appearance and presence of nuclear lipid inclusions. Cloisite 30B, therefore, induces toxic effects in HepG2 cells. Further research is needed to assess the risk of this clay on the human health.
authors.affiliation: Area of Toxicology, Faculty of Pharmacy, University of Seville, Profesor García González n°2, 41012 Seville, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Maisanaba
authors.forename: María
authors.initials: M
authors.lastname: Puerto
authors.forename: Silvia
authors.initials: S
authors.lastname: Pichardo
authors.forename: María
authors.initials: M
authors.lastname: Jordá
authors.forename: F Javier
authors.initials: FJ
authors.lastname: Moreno
authors.forename: Susana
authors.initials: S
authors.lastname: Aucejo
authors.forename: Ángeles
authors.initials: Á
authors.lastname: Jos
mesh_terms: D000538:Aluminum Silicates / Q000633:toxicity*; D017209:Apoptosis / Q000187:drug effects; D001546:Bentonite / Q000633:toxicity; D053148:Caspase 3 / Q000378:metabolism; D053179:Caspase 7 / Q000378:metabolism; D000077215:Clay; D020552:Comet Assay; D018857:Food Packaging; D005978:Glutathione / Q000378:metabolism; D056945:Hep G2 Cells / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D007249:Inflammation / Q000139:chemically induced / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008854:Microscopy, Electron; D009152:Mutagenicity Tests; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000538:Aluminum Silicates; C508600:IL6 protein, human; D015850:Interleukin-6; D017382:Reactive Oxygen Species; D001546:Bentonite; D053148:Caspase 3; D053179:Caspase 7; D005978:Glutathione; D000077215:Clay