EAPSI: Analyzing Sediment-Associated Zinc Nanoparticles in Aquatic Food Webs

Nanoparticles are used in personal care products and industry. They also form naturally from mining. The release of nanoparticles into aquatic ecosystems is rapidly increasing and receiving attention due to the potential environmental and human health risks. However, little is known on the risks that influence toxicity of nanoparticles. In collaboration with Dr. Shosaku Kashiwada, an expert in the field of environmental nanoscience, at the Research Center for Life and Environmental Sciences at Toyo University, this project will determine the fate of nanoparticles through an aquatic food chain from insect to fish. The uptake of metal nanoparticles from sediments and its potential impacts on the aquatic food web is not fully understood. This missing information is crucial as many fish species feed on sediment dwelling insects. Importantly, understanding the transfer of metals to fish will provide a resource for the public and policy makers to determine the risk of consuming fish from metal contaminated environments and the economic implications. <br/><br/>Zinc-nanoparticles are the focus of this research because of the high concentrations of zinc at metal-contaminated sites in the U.S. and in Japan. Zinc is also a significant contaminant of concern to regulatory agencies in both countries. Applications in applied ecotoxicology, gene expression and bio-imaging will be used to measure the trophic transfer of zinc nanoparticles in sediments in the laboratory. The proposed research is a novel approach for the growing practice of using gene expression to answer ecological questions. A field colonization experiment will also be conducted at a site impacted by metal contamination to identify the insects tolerant to metals and to quantify metal transfer up the food chain. The field study will fill in knowledge gaps needed to model the fate of metal nanoparticles in the aquatic food chain while addressing broad ecological questions about the usefulness of species traits in predicting effects of environmental stressors.<br/><br/>This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is jointly funded by NSF and the Japan Society for the Promotion of Science.