Genotoxicity, mutagenicity, and immunotoxicity assessment of green silver nanoparticles from Croton urucurana on neotropical snails Biomphalaria glabrata

Abstract

Green silver nanoparticles (G-Ag NPs) have been indicated as safer nanotechnology in nanomedicine, especially for controlling microorganisms, vectors, and gastropods of medical importance. However, their mechanisms of action and ecotoxicity in aquatic organisms remain unknown. Thus, the current study aimed to investigate the effects of G-Ag NPs synthesized through Croton urucurana leave aqueous extract on the neotropical freshwater snail Biomphalaria glabrata after in vivo exposure using multi-biomarker responses in hemocytes. Adult snails were exposed to G-Ag NPs (0.05 and 0.14 mg L−1) or leave aqueous extract (5.4 mg L−1) for 7 days. Genotoxicity (comet assay), mutagenicity (micronucleus test and nuclear abnormality assay), and immunotoxicity (phagocytosis assay by flow cytometry) were analyzed in hemocytes. Results showed that G-Ag NPs induced high mortality and genotoxic effects (DNA damage) compared to leave aqueous extract and negative control groups. G-Ag NPs also induced mutagenic effects (nuclear alterations), mainly notched and blebbed nuclei. Also, G-Ag NPs and extract did not change the phagocytic activity and cell viability of hemocytes. These findings contribute to understanding the toxicity of green nanoparticles in freshwater gastropods and represent a pioneering effort to evaluate the effects of G-Ag NPs and the C. urucurana aqueous extract in B. glabrata hemocytes. Overall, the immune system of gastropods is a target of green nanoparticle toxicity.