Antimicrobial effects of commercial silver nanoparticles are attenuated in natural streamwater and sediment.

Published

Journal Article

Given the demonstrated antimicrobial properties of silver nanoparticles (AgNPs), and the key role that microorganisms play in performing critical ecosystem functions such as decomposition and nutrient cycling, there is growing concern that AgNP pollution may negatively impact ecosystems. We examined the response of streamwater and sediment microorganisms to commercially available 21 ± 17 nm AgNPs, and compared AgNP impacts to those of dissolved-Ag added as AgNO(3). We show that in streamwater, AgNPs and AgNO(3) decreased respiration in proportion to dissolved-Ag concentrations at the end of the incubation (r(2) = 0.78), while in sediment the only measurable effect of AgNPs was a 14 % decrease in sulfate concentration. This contrasts with the stronger effects of dissolved-Ag additions in both streamwater and sediment. In streamwater, addition of dissolved-Ag at a level equivalent to the lowest AgNP dose led to respiration below detection, a 55 % drop in phosphatase enzyme activity, and a 10-fold increase in phosphate concentration. In sediment, AgNO(3) addition at a level equivalent to the highest AgNP addition led to a 34 % decrease in respiration, a 55 % increase in microbial biomass, and a shift in bacterial community composition. The results of this study suggest that, in similar freshwater environments, the short-term biological impacts of AgNPs on microbes are attenuated by the physical and chemical properties of streamwater and sediment.

Full Text

Duke Authors

Cited Authors

  • Colman, BP; Wang, S-Y; Auffan, M; Wiesner, MR; Bernhardt, ES

Published Date

  • October 2012

Published In

Volume / Issue

  • 21 / 7

Start / End Page

  • 1867 - 1877

PubMed ID

  • 22569948

Pubmed Central ID

  • 22569948

Electronic International Standard Serial Number (EISSN)

  • 1573-3017

International Standard Serial Number (ISSN)

  • 0963-9292

Digital Object Identifier (DOI)

  • 10.1007/s10646-012-0920-5

Language

  • eng