Antioxidant responses in the polychaete Perinereis gualpensis (Nereididae) exposed to the carbon nanomaterial fullerene (C60)

The objective of this study was to analyse biochemical responses induced by the carbon nanomaterial fullerene (C₆₀) in the polychaete Perinereis gualpensis (Nereididae). The activity of glutathione-S-transferase (GST), glutathione reductase (GR) and glutamate cysteine ligase (GCL), as well as total antioxidant capacity, concentration of glutathione (GSH) and malondialdehyde (TBARS), were analysed. Estuarine worms were maintained in sediments collected at an unpolluted site and spiked with fullerene (3 mg C₆₀·g^?1 sediment). A control group was run in parallel. Scanning electron microscope (SEM) images of sediment and fullerene indicated that the size of the carbon nanomaterial should enable it to be ingested by the polychaete. No evidence of oxidative damage (TBARS) was observed in any of the treatments, and the same was true for GSH and GCL measurements (p>0.05). Total antioxidant capacity was higher in the C₆₀ group after 2 and 7 d when compared with the control group (p<0.05), suggesting that fullerene is acting as an antioxidant. The fact that P. gualpensis is an infaunal organism diminishes the chance of fullerene photoexcitation with consequent reactive oxygen species production. Thus, the data indicated an absence of toxic responses mediated by oxidative stress in estuarine worms exposed to C₆₀ mixed in sediments.