Ecotoxicity of pristine graphene to marine organisms

• The ecotoxicity of pristine graphene was investigated in model marine organisms
• Acute toxicity effects were detected in V. fischeri and D. tertiolecta
• Acute toxicity was directed in (particles)size-dependent manner
• No acute toxicity was detected in A. salina
• An altered pattern of oxidative stress biomarkers was detected in exposed A. salina

The ecotoxicity of pristine graphene nanoparticles (GNC1, PGMF) in model marine organisms was investigated. PGMF resulted more toxic than GNC1 to the bioluminescent bacterium Vibrio fischeri and the unicellular alga Dunaliella tertiolecta on the basis of EC50 values (end-points: inhibition of bioluminescence and growth, respectively). No acute toxicity was demonstrated with respect to the crustacean Artemia salina although light microscope images showed the presence of PGMF and GNC1 aggregates into the gut; a 48-h exposure experiment revealed an altered pattern of oxidative stress biomarkers, resulting in a significant increase of catalase activities in both PGMF and GNC1 1 mg/L treated A. salina and a significant increase of glutathione peroxidase activities in PGMF (0.1 and 1 mg/L) treated A. salina. Increased levels of lipid peroxidation of membranes was also observed in PGMF 1 mg/L exposed A. salina.