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BACKGROUND: The potential human health risks from graphene inhalation exposure have attracted substantial scientific interest as a result of the numerous exciting potential commercial applications of graphene. However, the long-term distribution in organisms of graphene after inhalation is unknown, largely as a result of challenges associated with accurate graphene quantification. OBJECTIVES: Radioactively labeled graphene was used to evaluate its long-term biodistribution and toxicity in mice after intratracheal instillation. METHODS: Carbon-14 labeled graphene was used to quantify the in vivo distribution of graphene in rats after oral gavage or intratracheal installation for up to 3 d or 28 d after exposure, respectively, RESULTS: Intratracheally instilled graphene was mainly retained in the lung with 47% remaining after 4 weeks. Exposure to non-labeled graphene resulted in dose-dependent acute lung injury and pulmonary edema, but these effects were alleviated with time despite the continued presence of graphene in the lungs. Intratracheally instilled graphene was redistributed to the liver and spleen by passing through the air-blood barrier, a finding corroborated by the results of oral gavage experiments which did not show detectable absorption through the gastrointestinal tract. CONCLUSIONS: Carbon-14 labeled graphene enabled graphene quantification in environmental and biological media; intratracheally instilled graphene was redistributed to the liver and spleen and mainly retained in the lung with 47% remaining after 4 weeks; exposure to graphene resulted in dose-dependent acute lung injury and pulmonary edema, but these effects were alleviated with time despite the continued presence of graphene in the lungs.
Pan, B.
, Hu, M.
, Mao, L.
, Zhang, X.
and Petersen, E.
(2016),
Biodistribution and Toxicity of Radio-labeled Few Layer Graphene in Mice after Intratracheal Instillation, Environmental Health Perspectives
(Accessed October 27, 2025)