Sequential Studies of Silver Released from Silver Nanoparticles in Aqueous Media Simulating Sweat, Laundry Detergent Solutions and Surface Water

Abstract

From an increased use of silver nanoparticles (Ag NPs) as an antibacterial in consumer products follows a need to assess the environmental interaction and fate of their possible dispersion and release of silver. This study aims to elucidate an exposure scenario of the Ag NPs potentially released from, for example, impregnated clothing by assessing the release of silver and changes in particle properties in sequential contact with synthetic sweat, laundry detergent solutions, and freshwater, simulating a possible transport path through different aquatic media. The release of ionic silver is addressed from a water chemical perspective, compared with important particle and surface characteristics. Released amounts of silver in the sequential exposures were significantly lower, approximately a factor of 2, than the sum of each separate exposure. Particle characteristics such as speciation (both of Ag ionic species and at the Ag NP surface) influenced the release of soluble silver species present on the surface, thereby increasing the total silver release in the separate exposures compared with sequential immersions. The particle stability had no drastic impact on the silver release as most of the Ag NPs were unstable in solution. The silver release was also influenced by a lower pH (increased release of silver), and cotransported zeolites (reduced silver in solution).

Release of nanomaterials from solid nanocomposites and consumer exposure assessment – a forward-looking review

“…Hedberg et al (2014) used a different approach to address the Ag release from textiles in real life scenarios, exposing AgNP impregnated textiles to artificial sweat, laundry detergent and water solution in sequential and separate exposures. Their findings showed that Ag release from sequential exposures was by approximately a factor of 2 lower than the sum of release from separate exposures, which illustrates the importance of choosing an experimental setup to mimic the real world scenarios of textile use (Hedberg et al, 2014).…”

Agglomeration of Ag and TiO2 nanoparticles in surface and wastewater: Role of calcium ions and of organic carbon fractions

“…Silver and TiO 2 are among the most commonly encountered nanoparticles applied in consumer products in recent years (www.nanotechproject.org). However, their prevalent usage is of concern because of their possible release to the environment (Al-Kattan et al, 2014;Gondikas et al, 2014;Gottschalk and Nowack, 2011;Hedberg et al, 2014;Kaegi et al, 2013;Lombi et al, 2014), which may result in exposure of the ecosystem components and lead to adverse effects (Ali et al, 2014). Agglomeration and dissolution studies are providing valuable contributions for the speciation of the nanoparticles in the environment which are essential to develop an understanding of the mobility and transformation of ENPs.…”

Room Temperature Cation Exchange Reaction in Nanocrystals for Ultrasensitive Speciation Analysis of Silver Ions and Silver Nanoparticles

“…1,2 Their rapidly growing use inevitably releases large amounts of AgNPs to the environment and may cause environmental problems. 3,4 Despite increasing interest in their environmental effect and biological toxicity of AgNPs over the past several years, 5−8 the mechanisms of AgNPs toxicity remain largely in a state of "discussion" due to the complicated nature of the transformation and toxicology of AgNPs after entering organisms.…”