Published Paper Details:

The wide application of silver nanoparticles (Ag-NPs) has led to their significant environmental release, posing substantial ecotoxicological concerns for aquatic ecosystems. While the toxicity of chemically synthesized Ag-NPs (C-Ag-NPs) to freshwater fish, is well-established, the comparative toxicological implications of biogenic (green) synthesized Ag-NPs (G-Ag NPs) remain largely unexplored. This study aimed to assess and compare the dose- and time-dependent toxicity of C-Ag-NPs and G-Ag-NPs on the early life stages (spawn and fry) of the Indian major carp, rohu, Labeo rohita. Ag-NPs were synthesized by both chemical and green route method by using the leaf extract of Clitoria ternatea and characterised by UV-Vis spectroscopy (peak at 425 nm for both Ag-NPs), SEM (nanostructured, irregular shape), XRD (face-centred cubic crystalline structure), and FTIR (organic capping agents). The C-Ag-NPs and G-Ag-NPs when treated at varied concentrations of both Ag-NPs ranging from 0.01 mg/L to 1000 mg/L through water treatment with rohu spawn (24 hrs) and fry (7 days), demonstrated dose- and time-dependent mortality. 100% mortality of rohu spawn and fry was observed at higher concentrations (500-1000 mg/L) in both the Ag-NPs treatment groups. The C-Ag-NPs exhibited higher toxicity to rohu spawn at concentrations of 10 mg/L to 100 mg/L. Similarly, both types of Ag-NPs induced dose and time dependent oxidative stress with reduced liver GSH and increased lipid peroxidase activity in rohu fry. However, among the two types of AG-NPs, G-Ag-NPs resulted less lipid peroxidase activity and GSH depletion compared to C-Ag-NPs, suggesting a possible mitigated oxidative burden in fish. These findings underscore the significant ecotoxicological threat posed by Ag-NPs to aquatic life, particularly at early developmental stages.