EPA Science Inventory

Aging of Dissolved Copper and Copper-based Nanoparticles in Five Different Soils: Short-term Kinetics vs. Long-term Fate

Citation:

Sekine, R., E. Marzouk, M. Khaksar, K. Scheckel, J. Stegemeier, G. Lowry, E. Donner, AND E. Lombi. Aging of Dissolved Copper and Copper-based Nanoparticles in Five Different Soils: Short-term Kinetics vs. Long-term Fate. JOURNAL OF ENVIRONMENTAL QUALITY. American Society of Agronomy, MADISON, WI, 46(6):1198-1205, (2017). https://doi.org/10.2134/jeq2016.12.0485

Description:

With the growing availability and use of copper-based nanomaterials (Cu-NMs), there is increasing concern regarding their release and potential impact on the environment. In this study, the short term (≤5 d) aging profile and the long-term (135 d) speciation of dissolved Cu, copper oxide and copper sulfide nanoparticles (CuO-NPs and CuS-NPs) were investigated in five different soils using X-ray absorption spectroscopy. Soil pH was found to strongly influence the short-term chemistry of the Cu-NMs added at 100mg kg-1 above background. Low pH soils promoted rapid dissolution of CuO-NPs that effectively aligned their behavior to that of dissolved Cu within 3 d. In higher pH soils, CuO-NPs persisted longer due to slower dissolution in the soil and resulted in contrasting short-term speciation compared with dissolved Cu, which formed copper hydroxides and carbonates that were reflective of the soil chemistry. Organic matter appeared to slow the dissolution process, but in the long term, the speciation of Cu added as dissolved Cu, CuO-NPs, and CuS-NPs were found to be same for each soil. The results imply that, in the short term, Cu-NMs may exhibit unique behavior in alkaline soils compared with their conventional forms (e.g., in the event of an adverse leaching event), but in the long term (≥135 d), their fates are dictated by the soil properties, are independent of the initial Cu form, and likely to present minimal risk of nanospecific Cu-NM impact in the soil environment for the concentration studied here.

Purpose/Objective:

Short-term reactions of Cu are form (dissolved or nanoparticle) and soil chemistry dependent. In low pH soils, CuO-NPs dissolved rapidly and behaved similarly to dissolved Cu. CuO-NPs persisted longer in alkaline soils and in soils with high organic matter content. In the long term, Cu, CuO-NPs, and CuS-NPs transform into Cu bound to FeO(OH) or NOM. Chemical fate of Cu added to soils is largely independent of the original Cu form. This information is of interest to the bioavailability community.

URLs/Downloads:

https://dl.sciencesocieties.org/publications/jeq/articles/46/6/1198   Exit

Record Details:

Record Type: DOCUMENT (JOURNAL/PEER REVIEWED JOURNAL)
Start Date: 05/08/2017
Completion Date: 05/08/2017
Record Last Revised: 05/11/2018
Record Created: 03/12/2018
Record Released: 03/12/2018
OMB Category: Other
Record ID: 340008

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL RISK MANAGEMENT RESEARCH LABORATORY

LAND REMEDIATION AND POLLUTION CONTROL DIVISION

WASTE MANAGEMENT BRANCH