Subchronic oral toxicity study of Rajat Bhasma (RB) and green synthesized silver nanoparticles (AgNPs)

Introduction: Several researchers have suggested using metal nanoparticles as an alternative to metal Bhasma—a traditional method of metal processing—to overcome the lengthy and time-consuming nature of Bhasmikaran. Therefore, it is crucial to compare the safety profiles of Rajat Bhasma (RB) and silver nanoparticles (AgNPs) synthesized through green methods.Objective(s): This study compared the safety of Rajat Bhasma (RB) and silver nanoparticles (AgNPs) in a sub-chronic toxicity study.Materials and Methods: In this study, 42 rats were divided into seven groups, each comprising six animals (three males and three females). Six groups were administered either Rajat Bhasma or silver nanoparticles orally for 28 days at therapeutically equivalent doses (TED) of 10.8 mg/kg, 10 × TED (108 mg/kg), and 20 × TED (216 mg/kg). Toxicity was evaluated based on general observations and hematological, biochemical, and histopathological assessments.Results: The results demonstrated that Rajat Bhasma and silver nanoparticles administered at 10- and 20-fold TED doses adversely affected specific hematological parameters, including platelet count, mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) levels. Additionally, AgNPs induced alterations in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, indicating hepatic toxicity, which was further corroborated by histopathological examination of the liver. Hydropic degeneration and congestion in the kidneys were observed in rats treated with RB at the 20 × TED dose and in all AgNP-treated groups.Conclusion: RB and AgNPs were safe at therapeutically equivalent doses. However, AgNPs showed greater toxicity at higher doses compared to RB.