Dietary toxicity of single-walled carbon nanotubes and fullerenes (C₆₀) in rainbow trout (Oncorhynchus mykiss)

Abstract

The objective of this investigation was to compare the toxicity of two manufactured carbon nanomaterials (CNs) to determine if shape influenced toxicity. Juvenile rainbow trout Oncorhynchus mykiss were fed a control diet (no CN addition), or a diet supplemented with 500 mg single-walled carbon nanotubes (SWCNT) kg(-1) or 500 mg C(60) kg(-1) for six weeks. Fish growth, haematology, tissue ion concentrations, histopathology, osmoregulation, and biochemistry were evaluated. At week 4, but not on weeks 2 and 6, significant elevation in brain TBARS (an indication of lipid peroxidation) was observed in fish exposed to SWCNTs (16.2 ± 1.38 nmol mg(-1) protein) compared to the control (9.11 ± 0.81 nmol mg(-1) protein) and fish exposed to C(60) (8.28 ± 0.56 nmol mg(-1) protein). No other significant treatment-related differences were observed. Results indicate that dietary exposure to SWCNTs and C(60) in rainbow trout did not result in overt toxicity.

Effects of Ingested Multi-Walled Carbon Nanotubes in Poecilia reticulata: Localization and Physiological Responses

“…In a study similar to the present, Smith and colleagues demonstrated CNT's affinity for mucous membranes in gill surfaces of fish [14]. In another study by Fraser et al SWCNTs on juvenile rainbow trout, Onchorhychus mykiss, revealed a dose-dependent accumulation of the SWCNTs aggregated with gill mucous which increased mucous secretion, oedema, altered mucocytes and hyperplasia [47]. In a more recent study similar to the present, Bisesi et al histologically showed that SWCNTs sloughed off gastrointestinal epithelial wall of the fish Pimephales promelas [48].…”

Methodological considerations for testing the ecotoxicity of carbon nanotubes and fullerenes: Review

“…Chem. 31,2012exposure to either C 60 or SWNTs (500 mg/kg food) did not result in differences in toxicity [51], whereas, in another study, a smaller carbonaceous nanofiber fraction, rods with diameters of 1 nm and lengths less than 18 nm, increased lifetime mortality of the estuarine copepod Amphiascus tenuiremis relative to purified SWNTs at the same concentration (10 mg/L) [52]. Further work on the effects of CNP shape related to toxicity is clearly warranted.…”

Fullerenes(nC60) affect the growth and development of the sediment-dwelling invertebrate Chironomus riparius larvae

“…These stems from ecotoxicology assays, where fullerenes were observed to cause the immobility of the water flea Daphnia magna (Lovern and Klaper, 2006) and packing in the gut thus causing high concentrations in the organisms' wet mass basis (Tervonen et al, 2010). On the other hand, acute toxicity tests have reported that fullerenes cause only minor or negligible effects to aquatic organisms (Tervonen et al, 2010;Pakarinen et al, 2011;Fraser et al, 2011;Petersen and Henry, 2012). There is a lack of conclusive data on chronic exposures; some evidence on benthic invertebrates has been reported (Waissi-Leinonen et al, 2012;Pakarinen et al, 2011;Oberholster et al, 2011) and even fewer studies of chronic toxicity to water flea D. magna (Tao et al, 2009).…”