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Effects of SiO₂, ZrO₂, and BaSO₄ nanomaterials with or without surface functionalization upon 28-day oral exposure to rats.

ABSTRACT: The effects of seven nanomaterials (four amorphous silicon dioxides with or without surface functionalization, two surface-functionalized zirconium dioxides, and barium sulfate) upon 28-day oral exposure to male or female rats were investigated. The studies were performed as limit tests in accordance with OECD Test Guideline 407 applying 1,000 mg test substance/kg body weight/day. Additionally, the acute phase proteins haptoglobin and α2-macroglobulin as well as cardiac troponin I were determined, and metabolome analysis was performed in plasma samples. There were no test substance-related adverse effects for any of the seven nanomaterials. Moreover, metabolomics changes were below the threshold of effects. Since test substance organ burden was not analyzed, it was not possible to establish whether the lack of findings related to the absence of systemic exposure of the tested nanomaterials or if the substances are devoid of any potential for toxicity. The few published subacute oral or short-term inhalation studies investigating comparable nanomaterials (SiO₂, ZrO₂, and BaSO₄) also do not report the occurrence of pronounced treatment-related findings. Overall, the results of the present survey provide a first indication that the tested nanomaterials neither cause local nor systemic effects upon subacute oral administration under the selected experimental conditions. Further investigations should aim at elucidating the extent of gastrointestinal absorption of surface-functionalized nanomaterials.

SUBMITTER: Buesen R

PROVIDER: S-EPMC4161931 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Effects of SiO₂, ZrO₂, and BaSO₄ nanomaterials with or without surface functionalization upon 28-day oral exposure to rats.

Buesen Roland R Landsiedel Robert R Sauer Ursula G UG Wohlleben Wendel W Groeters Sibylle S Strauss Volker V Kamp Hennicke H van Ravenzwaay Bennard B

Archives of toxicology 20140828 10

The effects of seven nanomaterials (four amorphous silicon dioxides with or without surface functionalization, two surface-functionalized zirconium dioxides, and barium sulfate) upon 28-day oral exposure to male or female rats were investigated. The studies were performed as limit tests in accordance with OECD Test Guideline 407 applying 1,000 mg test substance/kg body weight/day. Additionally, the acute phase proteins haptoglobin and α2-macroglobulin as well as cardiac troponin I were determine ...[more]

PMID: 25164825

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Dataset Information

Effects of SiO₂, ZrO₂, and BaSO₄ nanomaterials with or without surface functionalization upon 28-day oral exposure to rats.

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Effects of SiO₂, ZrO₂, and BaSO₄ nanomaterials with or without surface functionalization upon 28-day oral exposure to rats.

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