Reproductive and whole-body toxicity of Ag-doped and -undoped ZIF-8 nanoparticles and the building blocks: An Artemia-based comparative bioassay.

The present research assessed, for the first time, toxicity of ZIF-8 (1 mg/L) and the building blocks (0.1 mg/L Zn2+ and 0.4 mg/L 2-methylimidazole (2-MIm)), besides that of AgNPs@ZIF-8 (0.25, 0.5, and 1 mg/L) and AgNO3 (0.1 mg/L) to aquatic organisms. Two consecutive generations (F0 & F1) of Artemia salina were exposed to these chemicals. All of the chemical treatments considerably caused mortality in F0, especially AgNPs@ZIF-8 and AgNO3, whereas F1 displayed notable tolerance and survived comparable to the control group, except in the case of AgNO3 treatment. Similarly, growth indices (weight, mainly in ZIF-8, Zn2+, and 2-MIm; length, in Ag-doped ZIF-8 and AgNO3) were significantly retarded in F0 and especially F1 of all treatments, and 2-MIm caused the greatest length retardation in F0. AgNPs@ZIF-8 (0.5 and 1 mg/L), 2-MIm, and AgNO3 postponed the ovary emergence in about 40%-60% of the exposed F0, and ZIF-8 delayed this phenomenon in some individuals of F0 and F1 up to 6 days. This temporal disturbance was also observed in time to first brood of almost all experimental F0 and F1 groups, with being over 80% of F1 exposed to ZIF-8, 2-MIm, and Zn2+, as well as about 50% of F0 treated with 2-MIm, and Zn2+. The highest neonate number was recorded for F0 and F1 exposed to AgNO3 and Zn2+, while ZIF-8 and, importantly, 2-MIm decreased the reproductivity to the lowest levels in both generations. Generally, the reproductive frequency was significantly decreased in all F0 and F1 treatments, especially 2-MIm, ZIF-8, AgNPs@ZIF-8 (0.25 & 1 mg/L). This study highlighted the neglected importance of 2-MIm in assessing overall toxicity of ZIF-8, and even other organic ligands of MOFs, and also filled a gap in the literature by investigating the potential effect of additives such as AgNPs on the toxicity of ZIF-8 and other MOFs.

Individual and binary exposure to nanoscales of silver, titanium dioxide, and silicon dioxide alters viability, growth, and reproductive system: Hidden indices to re-establish artemia as a toxicological model in saline waters.

This study evaluated and compared the individual and combined toxicity of AgNPs, TiO2NPs, and SiO2NPs to life cycle of A. salina. To this end, both stability and toxicity of AgNPs were determined in the presence of TiO2NPs and SiO2NPs. The colloidal stability of AgNPs decreased in the presence of the other two NPs, especially SiO2NPs. AgNPs displayed acute toxicity to A. salina, whereas SiO2NPs and TiO2NPs chronically induced toxicity in a concentration- and time-dependent manner during 28-day exposure. The experimental NPs significantly decreased the weight and length of A. salina and induced reproductive toxicity through perturbation in first brood timespan, sexual maturity, egg development time, egg pouch area, offspring quality, and fecundity. Exposure to AgNPs shifted the mode of reproduction in brine shrimp from ovoviviparity to oviparity, and also co-presence of AgNPs with SiO2NPs or TiO2NPs caused infertility. Generally, their individual toxicity was in order of AgNPs > TiO2NPs > SiO2NPs, and binary exposure to AgNPs-SiO2NPs appear to be more threatening than AgNPs-TiO2NPs to A. salina. Together, this study highlights that these nanoparticles could disrupt reproductive health of A. salina and lead to alterations in population dynamics and aquatic ecosystem balance.