Safety considerations for graphene: lessons learnt from carbon nanotubes

Area of Science:

• Nanotechnology
• Materials Science
• Toxicology

Background:

• Carbon nanomaterials, including graphene and carbon nanotubes, show immense potential due to unique properties.
• Graphene's increasing industrial use necessitates understanding its safety profile.
• Direct comparative safety studies between graphene and carbon nanotubes are limited.

Purpose of the Study:

• To compare the safety profiles of graphene and carbon nanotubes based on physicochemical properties and known health effects.
• To identify key factors influencing the toxicological outcomes of these nanomaterials.
• To propose design principles for developing safer graphene-based materials for human use.

Main Methods:

• Comparative analysis of physicochemical characteristics (structure, surface, colloidal properties) of graphene and carbon nanotubes.
• Review of existing evidence on health effects at cellular, tissue, and whole-body levels.
• Formulation of safety guidelines based on material properties and biological interactions.

Main Results:

• Graphene exhibits lower aspect ratio, larger surface area, and better dispersibility than carbon nanotubes.
• Graphene nanostructures are not fiber-shaped, potentially offering safety advantages over carbon nanotubes.
• Material dimensions, surface chemistry, and impurities critically influence mechanistic and toxicological outcomes for both.

Conclusions:

• Graphene's distinct properties suggest potential safety benefits over carbon nanotubes, but direct comparative data is scarce.
• Proposed rules for safer graphene development include using small, individual, stable, and excretable forms.
• Generalizations about graphene toxicity are discouraged; safety depends on specific material types and applications.