Reliable predictions of the environmental fate and risk of engineered nanomaterials (ENMs) require a better understanding of ENM reactivity in complex, biologically active systems for chronic low concentration exposure scenarios. Here, simulated freshwater wetland mesocosms were dosed with ENMs to assess how their reactivity, and seasonal changes in environmental parameters, influence ENM fate in aquatic environments. Copper-based ENMs (Kocide), known to dissolve in water, and gold nanoparticles (AuNPs), stable against dissolution in the absence of specific ligands, were added weekly to mesocosm waters for 9 months. Metal accumulation and speciation changes in the different environmental compartments were assessed over time. Copper from Kocide rapidly transported to terrestrial soils and deeper sediment and associated to organic or sulfide phases. In contrast, Au accumulated on/in the macrophytes in the oxidized form, and over time transferred to the surficial sediment. A dynamic seasonal accumulation and metal redox cycling was found between the macrophyte and the surficial sediment for AuNPs. These results demonstrate the need for experimental quantification of how biological and chemical complexity of the environment combine with their seasonal variations, can drive the fate of metastable ENMs.

Seasonal biogeochemical cycling of copper- and gold-based engineered nanomaterials in a freshwater wetland mesocosm

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.