In the present in vivo study, we provide a comparison of toxicological consequences induced by four different types of spherical nanoparticles (NPs)—silver nanoparticles (AgNPs, 40 ± 6 nm), nickel (NiNPs, 43 ± 6 nm), cobalt oxide (Co3O4NPs, 60 ± 6 nm), and chromium oxide (Cr3O4NPs, 50 ± 5 nm)—on freshwater ...