RETRACTED: Evaluation of Chronic Nanosilver Toxicity to Adult Zebrafish

Abstract

Nanotechnology is rapidly growing with nanoparticles produced and utilized in a wide range of commercial products worldwide. Among the different types of nanomaterials produced, silver nanoparticles (AgNPs) occupy a predominant position and they are used in electronics, clothing, food industry, cosmetics and medical devices. Nanosilver has also showed excellent performance in antibacterial application. Nowadays, the increasing use of AgNPs has put the evidence on their possible toxicity to the human health and the impact on the environment. This paper focus on adverse effects of AgNPs in adult of Danio rerio. Fishes exposed to increasing concentrations (8, 45, and 70 μg/l) silver nanoparticles (AgNPs, 25 nm in average diameter) and after treatment for 30 days, was quickly euthanized in MS-222. We have evaluated bioaccumulation of AgNPs using ICP-MS and analyzed histological changes, biomarkers of oxidative damage and gene expression in the gut, liver and gills tissues of AgNPs-treated zebrafish. The histological analysis showed lesions of secondary lamellae of the gills with different degrees of toxicity such as hyperplasia, lamellar fusion, subepithelial edema, and even in some cases telangiectasia. Huge necrosis of the intestinal villi was found in the gut. No lesion was detected in the liver. The analysis revealed a high expression of metallothioneins 1 (MTs 1) in animals exposed to AgNPs compared to the control group. The ICP-MS analysis shows that the amount of particles absorbed in all treated samples is almost the same. We can affirm that AgNPs toxicity linked more to their size and state of aggregation than to their concentrations. Silver nanoparticles can damage gills and gut because they are able to pass through the mucosal barrier thanks to their small size. The damage is still reversible because it is not documented injury to the basal membrane.

Morphostructural and immunohistochemical study for evaluation of nano‐TiO2toxicity inArmadillo officinalisDuméril, 1816 (Crustacea, Isopoda, Oniscidea)

“…Several studies have showed a correlation between the concentration of toxic substances and the capacity of different organisms to respond to exposure. The biological response can encompass change of vitality, morphological and physiological modifications or genetic damage (Morgano et al, ; Perugini et al, ; Salvaggio et al, ).…”

“…Furthermore they present an organ primarily involved in the accumulation of xenobiotics (Costa, Bouchon, Van Straalen, Sousa, & Ribeiro, ; Hussein, Obuid‐Allah, Mohammad, Scott‐Fordsmand, & Abd El‐Wakeil, ; Longo et al, ; Mazzei et al, ), the hepatopancreas and a detoxification system of heavy metals which involves the induction of the expression of the metallothioneins (Droutsa et al, ; Mazzei et al, ). Metallothioneins 1 (MT1) are called exposure biomarkers and are part of a superfamily of low molecular mass cytoplasmic proteins, characterized by a high cysteine content and the absence of aromatic aminoacids and histidine, that are involved in the regulation of essential metals metabolism, in heavy metal detoxification and in protection against oxidative stress (Ferrante et al, ; Salvaggio et al, ; Viarengo, Burlando, Ceratto, & Panfoli, ) and also in metallic nanoparticles detoxification (Brundo et al, ; Pecoraro, Marino, et al, ; Pecoraro, Salvaggio, et al, ).…”

Evaluation of the effects of silver nanoparticles on Danio rerio cornea: Morphological and ultrastructural analysis

“…Several organisms are used as models in toxicological studies (Conte et al, 2016;Copat et al, 2012;D'Agata et al, 2014;De Domenico et al, 2011;Kanold, Wang, Brümmer, & Šiller, 2016;Mazzei et al, 2014;Scuderi et al, 2014;Wang, Jia, Zhu, Zhang, & Wang, 2017;Xiao, Vijver, Chen, & Peijnenburg, 2015), and among these, presently, zebrafish is considered the model organism, best suited, for toxicological testing Buccheri et al, 2016;Pecoraro et al, 2018;Pecoraro, D'Angelo, et al, 2017;Pecoraro, Salvaggio, et al, 2017;Salvaggio et al, 2016;Wang et al, 2011). Different types of parameters are used to evaluate NPs toxicity such as hatching F I G U R E 3 Scanning electron microscopy of the corneal surface reveals the presence of microvilli and microplicae and fingerprintlike structures.…”

“…Several studies on animal models have shown that NPs can be potentially toxic (Hu et al, ; Lankveld et al, ), and that toxicity of NPs depends certainly on their size (Lankveld et al, ). Among the different animal models, zebrafish or Danio rerio is considered an excellent model for nanotoxicity studies for some particular features of these animals (Brundo et al, ; Lee, Nallathamby, Browning, Osgood, & Xu, ; Pecoraro et al, ; Pecoraro et al, ; Pecoraro et al, ; Salvaggio et al, ; Sarasamma et al, ; Zhao et al, ).…”

Toxicity assessment of nano‐TiO2inApis melliferaL., 1758: histological and immunohistochemical assays

“…These biomarkers, used in previous studies, have proved excellent biomarkers of exposure to metallic xenobiotic in different animals (Droutsa et al, ; Ferrante et al, ; Mazzei et al, ; Piscopo et al, ; Salvaggio et al, ); they have been chosen because it has been shown that they intervene in the detoxification processes of metallic nanoparticles (Brundo et al, ; Pecoraro, Marino, et al, ; Pecoraro, Salvaggio, et al, ).…”