Reproductive performance of freshwater snail, Helisoma duryi under the effect of bulk and nano zinc oxide

Abstract

Nanotechnology has been used to apply nanoparticle essential elements to enhance the ability of animals to absorb these elements and consequently improve their reproductive performance. High concentrations of nanoparticles (NPs) can directly harm a range of aquatic life forms, ultimately contributing to a decline in biodiversity. Helisoma duryi snails are a good model for studying the toxicological effects of bulk zinc oxide (ZnO‐BPs) and nano zinc oxide (ZnO‐NPs) on freshwater gastropods. This study aimed to compare the toxic effects of ZnO‐BPs and ZnO‐NPs on H. duryi snails and explore how waterborne and dietary exposure influenced the reproductive performance of this snail. ZnO‐BPs and ZnO‐NPs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X‐ray powder (XRD). This study revealed that the size of ZnO‐BPs and ZnO‐NPs were 154 nm and 11–31 nm, respectively. The results showed that exposure of adult snails to sub‐lethal concentrations of both ZnO forms (bulk and nano) for 24 h/week for 4 weeks markedly changed their reproductive performance in a concentration‐dependent manner, where fecundity was negatively affected by high concentrations. It was concluded that dietary exposure to the lowest tested concentration of ZnO‐NPs (1 ppm) has a positive effect as the number of eggs and egg masses/snails increased and the incubation period decreased. Also, poly‐vitelline eggs (The formation of twins) were observed. ZnO‐NPs at low concentrations positively affect the reproductive performance of snails, especially after dietary exposure. The results revealed that 1 ppm ZnO‐NPs could be supplementary provided to snails to improve their fertility, reduce the developmental time course, increase hatchability percentage, and produce poly‐vitelline eggs.

Evaluation of the teratogenic potency of bulk zinc oxide and its nanoparticles on embryos of the freshwater snail, Helisoma duryi

“…The morphological characters and particle size of ZnO-BPs and synthesized ZnO-NPs were investigated and visualized in our previous study 44 using scanning electron microscopy (SEM; JEOL JSM-5300) transmission electron microscopy (TEM; JEOL JEM-2100). The particles were examined at different resolutions and magnification powers in a random field of view.…”

“…The particles were examined at different resolutions and magnification powers in a random field of view. X-ray Powder Diffraction (XRD Shimadzu 6000) analyses were performed previously at Nano Science and Technology Institute, Kafrelsheikh University, Egypt 44 .…”