Carbon nanofibers caused oxidative stress and disrupted anti-predator responses in common spiny loach

Abstract

Carbon nanofibers, recently recognized pollutants, have been heavily used among the nanomaterials in many industries. Due to the poor suspension-stability, carbon nanofibers tend to sediment at the bottom of waterbodies and hence can be consumed by the bottom-dwellers. The current investigation evaluates the impact of carbon nanofibers at concentrations between 0.1 and 10 mg L⁻¹ on the common bottom dweller spiny loach Lepidocephalichthys thermalis inhabiting Indian rivers. Carbon nanofiber exposure elevated the activities of the hepatic antioxidant enzymes superoxide dismutase, catalase, peroxidase and glutathione S-transferase, as oxidative stress markers. The fish behaviour patterns were examined by testing the effect of carbon nanofibers on predator recognition ability using kairomones, conspecific alarm cues, and dietary cues. The carbon nanofiber-exposed fish showed a loss of predator-recognition abilities. The results collectively demonstrated the carbon nanofiber driven hepatic oxidative damage and impaired predator-recognition ability in L. thermalis. The investigation, first of its kind, highlights the toxic potential of the carbon nanofibers on benthic fishes.

Keywords:

• Antioxidant enzymes
• behavior
• carbon nanofibers
• chemical cues
• Lepidocephalichthys thermalis
• predator recognition

Acknowledgements

Authors acknowledge the use of facilities created under DST-FIST (SR/FST/COLLEGE-/19/568) program, DBT Star Status (BT/HRD/11/030/2012) and DBT-BUILDER (BT/INF/22/SP45363/2022) schemes implemented at Modern College of Arts, Science and Commerce, Ganeshkhind, Pune, India. LK, CRV and PK acknowledge the support by IRP ČZU MŠMT 604670901. The study was partially funded by the institutional grant SGS conducted at the Czech University of Life Sciences Prague under No. SV23-11-21260.

Disclosure statement

No potential conflict of interest was reported by the authors.