Emerging contaminant or an old toxin in disguise? Silver nanoparticle impacts on ecosystems.

Published

Journal Article

The use of antimicrobial silver nanoparticles (AgNPs) in consumer-products is rising. Much of these AgNPs are expected to enter the wastewater stream, with up to 10% of that eventually released as effluent into aquatic ecosystems with unknown ecological consequences. We examined AgNP impacts on aquatic ecosystems by comparing the effects of two AgNP sizes (12 and 49 nm) to ionic silver (Ag(+); added as AgNO3), a historically problematic contaminant with known impacts. Using 19 wetland mesocosms, we added Ag to the 360 L aquatic compartment to reach 2.5 mg Ag L(-1). Silver treatments and two coating controls were done in triplicate, and compared to four replicate controls. All three silver treatments were toxic to aquatic plants, leading to a significant release of dissolved organic carbon and chloride following exposure. Simultaneously, dissolved methane concentrations increased forty-fold relative to controls in all three Ag treatments. Despite dramatic toxicity differences observed in lab studies for these three forms of Ag, our results show surprising convergence in the direction, magnitude, and duration of ecosystem-scale impacts for all Ag treatments. Our results suggest that all forms of Ag changed solute chemistry driving transformations of Ag which then altered Ag impacts.

Full Text

Duke Authors

Cited Authors

  • Colman, BP; Espinasse, B; Richardson, CJ; Matson, CW; Lowry, GV; Hunt, DE; Wiesner, MR; Bernhardt, ES

Published Date

  • May 2014

Published In

Volume / Issue

  • 48 / 9

Start / End Page

  • 5229 - 5236

PubMed ID

  • 24693948

Pubmed Central ID

  • 24693948

Electronic International Standard Serial Number (EISSN)

  • 1520-5851

International Standard Serial Number (ISSN)

  • 0013-936X

Digital Object Identifier (DOI)

  • 10.1021/es405454v

Language

  • eng