Development of a robust method for measuring engineered nanomaterial toxicity and uptake using Caenorhabditis elegans

S.K. Hanna, M.E. Johnson, L.L. Yu, B.C. Nelson, G.A. Cooksey, J.T. Elliott, E.J. Petersen
National Institute of Standards and Technology, US

Keywords: C. elegans, toxicity assay, uptake, high content

Summary:

As more uses for engineered nanoparticles (ENPs) are being realized, increasing masses of ENPs are being produced and, therefore, released into the environment, sparking concern regarding their ecological consequences. However, there is a lack of standardized methods for determining the toxicity of ENPs at environmentally relevant concentrations within in vivo model systems. The nematode C. elegans provides a useful model for studying the uptake and impacts of nanoparticles on organisms in the environment because its short life span allows for full life cycle exposures in 96 hour studies. Additionally, C. elegans is ecologically important due to its widespread distribution in bacteria-rich environments. Here we assess the adequacy of an ISO protocol for measuring toxicity effects of chemicals on C. elegans for measuring potential toxicity effects from NIST reference nanoparticles. Additionally, we use single particle inductively coupled mass spectroscopy to determine the extent to which particles are accumulated by the nematodes and characterize the particles ingested by the organism. This approach allows us to determine both the toxicity of the ENPs and the potential for trophic transfer. We discuss method development and preliminary results using our model system.