The Recent Progress in Nanotoxicology and Nanosafety from the Point of View of Both Toxicology and Ecotoxicology

In Silico Simulation of Impacts of Metal Nano-Oxides on Cell Viability in THP-1 Cells Based on the Correlation Weights of the Fragments of Molecular Structures and Codes of Experimental Conditions Represented by Means of Quasi-SMILES

A simulation of the effect of metal nano-oxides at various concentrations (25, 50, 100, and 200 milligrams per millilitre) on cell viability in THP-1 cells (%) based on data on the molecular structure of the oxide and its concentration is proposed. We used a simplified molecular input-line entry system (SMILES) to represent the molecular structure. So-called quasi-SMILES extends usual SMILES with special codes for experimental conditions (concentration). The approach based on building up models using quasi-SMILES is self-consistent, i.e., the predictive potential of the model group obtained by random splits into training and validation sets is stable. The Monte Carlo method was used as a basis for building up the above groups of models. The CORAL software was applied to building the Monte Carlo calculations. The average determination coefficient for the five different validation sets was R² = 0.806 ± 0.061.

Toxic Effects and Mechanisms of Silver and Zinc Oxide Nanoparticles on Zebrafish Embryos in Aquatic Ecosystems

The global application of engineered nanomaterials and nanoparticles (ENPs) in commercial products, industry, and medical fields has raised some concerns about their safety. These nanoparticles may gain access into rivers and marine environments through industrial or household wastewater discharge and thereby affect the ecosystem. In this study, we investigated the effects of silver nanoparticles (AgNPs) and zinc oxide nanoparticles (ZnONPs) on zebrafish embryos in aquatic environments. We aimed to characterize the AgNP and ZnONP aggregates in natural waters, such as lakes, reservoirs, and rivers, and to determine whether they are toxic to developing zebrafish embryos. Different toxic effects and mechanisms were investigated by measuring the survival rate, hatching rate, body length, reactive oxidative stress (ROS) level, apoptosis, and autophagy. Spiking AgNPs or ZnONPs into natural water samples led to significant acute toxicity to zebrafish embryos, whereas the level of acute toxicity was relatively low when compared to Milli-Q (MQ) water, indicating the interaction and transformation of AgNPs or ZnONPs with complex components in a water environment that led to reduced toxicity. ZnONPs, but not AgNPs, triggered a significant delay of embryo hatching. Zebrafish embryos exposed to filtered natural water spiked with AgNPs or ZnONPs exhibited increased ROS levels, apoptosis, and lysosomal activity, an indicator of autophagy. Since autophagy is considered as an early indicator of ENP interactions with cells and has been recognized as an important mechanism of ENP-induced toxicity, developing a transgenic zebrafish system to detect ENP-induced autophagy may be an ideal strategy for predicting possible ecotoxicity that can be applied in the future for the risk assessment of ENPs.

Nanosafety: a knowledge, attitude and practice (KAP) study among Iranian researchers working in nanotechnology laboratories

Objectives. There is a set of evidence about the adverse effects of engineered nanomaterials (ENMs) on humans and the environment. People working with nanomaterials (NMs) (in nanotechnology laboratories and workplaces) are often exposed to these materials. Following nanosafety principals can reduce exposure to ENMs. This study aimed to investigate the knowledge, attitude and practice (KAP) of Iranian researchers toward nanosafety. Methods. This descriptive cross-sectional study was conducted via a questionnaire designed using the results of a literature review and validated by a panel of experts. After completion of questionnaires by Iranian researchers, data were analyzed using SPSS version 20.0. Results. Investigation into the knowledge of study participants showed that 61.38% of them answered the questions correctly. Although 74.34% of the study participants had a proper attitude to nanosafety, only 27.3% of them considered ENMs to be harmful to humans and the environment. Examination of researchers' performance in laboratories showed that 24.25% of them 'always' have good performance. Conclusions. It seems that increasing awareness by teaching the principles of working safely with NMs can help to create a positive attitude toward the principles of nanosafety. Positive attitude can finally lead to the optimal performance of researchers in laboratories involved with NMs.