Toxicity of PVA-stabilized silver nanoparticles to algae and microcrustaceans

• Pseudokirchneriella subcapitata, Artemia salina and Daphnia similis were used as model organisms to investigate the toxicity of PVA-stabilized AgNP.
• Synthesized AgNP were physico-chemically characterized by UV–vis spectroscopy, particle size distribution, zeta potential analyzes and Transmission Electron Microscopy (TEM).
• AgNP showed lower toxicity to A. salina and P. subcapitata organisms compared with data found in the literature, with EC50 5.5 × 10−2 mg L−1 and 1.09 mg L−1 respectively.
• AgNP showed high toxicity to D. similis with EC50 (48 h) 2.62 × 10−4 mg L−1.

Over the years there has been a significant increase in the manufacturing of silver nanoparticles-based products, mainly due to their antimicrobial activity, with application in medicine and textile and food industry. However, the inappropriate use and disposal of these materials can allow the entry of silver nanoparticles (AgNP) into the aquatic environment, with potential toxicological effects. In this study we used Pseudokirchneriella subcapitata, Artemia salina and Daphnia similis as model organisms to investigate the toxicity of PVA-stabilized AgNP at several concentration levels. AgNP were physico-chemically characterized by UV–vis spectroscopy, particle size distribution, zeta potential analyzes and Transmission Electron Microscopy (TEM). AgNP presented a maximum absorption at 400 nm and size range between 2 and 18 nm. Each specific organism was exposed to AgNP concentrations through standardized protocol. For P. subcapitata and A. salina the EC50 value found, 1.09 mg L−1 and 5.5 × 10−2 mg/L, respectively, were in accordance to previous results reported in the literature. However, for D. similis, the EC50 24–48 h values indicate a higher toxicity than other results reported for other daphnids.