A mechanistic understanding of nanomaterial (NM) interactions with agricultural crops remains elusive. In one study, fullerenes or MWCNTs were added (0, 500, 1000, or 5000 mg/Kg) to soil containing weathered chlordane and DDX (DDT + metabolites) that was subsequently planted with zucchini, corn, tomato, or soybean for 28d. MWCNT reduced pesticide accumulation by all plants in a concentration dependent fashion, with decreases ranging from 20% to 100-fold. Fullerenes either had minimal impact on pesticide fate or in some cases, significantly increased organochlorine uptake. These findings show that the carbon nanomaterial properties may significantly influence co-contaminant-NM interactions in agricultural systems. Separately, cerium oxide trophic transfer was evaluated. Bulk or nanoparticle cerium oxide was added to soil (1000 mg/Kg) that was subsequently planted with zucchini for 28d. At harvest, plant cerium content was determined by ICP-MS. Bulk cerium levels in plant roots, stems, leaves and flowers were 140, 0.29, 0.69, and 0.04 mg/Kg, respectively. However, preliminary data shows significantly greater cerium levels detected in all tissues when the exposure was in nanoparticle form; extraction and analysis is ongoing at this time. Select leaves (bulk or NP-exposed) were fed to crickets for 21 days. Cricket tissues will be digested for ICP-MS or fed to predatory mantids, which will then be analyzed for cerium content. Results from these ongoing experiments will characterize the particle size-specific trophic transfer of cerium in a terrestrial food chain.

Engineered nanomaterials and agricultural crops: Co-contaminant interactions and trophic transfer

247th National Meeting (2014)

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