Actual whole layer graphene is not a major risk afaik, simply because it would not be metabolized and doesn't reach cells. However, if you go to the nanographene range, that changes massively. Nanographene is equivalent to large polycyclic aromatic hydrocarbons (PAHs) and for these it should be easy to find information on carcinogenity: it is associated with epoxide formation and via these, an attachment to DNA is possible.

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Graphene and graphene oxide have raised concerns regarding potential cancer risks, though the research is still evolving. Some studies suggest these materials may promote tumor growth or have carcinogenic potential, possibly through mechanisms like generating reactive oxygen species or causing DNA damage. However, the risks depend on factors such as dose, exposure route, and the specific properties of the graphene material. Much of the current data comes from in vitro or animal studies, and long-term effects in humans are not well established. While some research indicates potential anti-cancer effects in certain contexts, the complex interactions of graphene materials with biological systems are not fully understood. More comprehensive safety data is needed for a thorough risk assessment, and currently, most countries lack specific regulations for these materials.

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