Impacts of Particle-Based Dispersants on Benzene Bioavailability and on Toxicity Using Artemia Franciscana As a Model Organism

Nanoparticles are able to assemble at water-oil interfaces and stabilize fine oil droplets, forming what is known as a Pickering emulsion.  Nanoparticles are a possible alternative to the chemical dispersants typically deployed after an oil spill.  Both particle and chemical based dispersants serve to limit petroleum accumulation at the ocean surface and accelerate biodegradation processes by increasing the oil-water interfacial area.  The potential advantage of our carbon black particle –based Pickering emulsion is the ability to not only stabilize droplets but also to adsorb the more water-soluble and toxic fractions of petroleum. Benzene is used as a model aromatic compound to determine the efficacy of the carbon black particles to adsorb and retain (therefore reducing the bioavailability) these fractions as a function of tunable hydrophilicity.  Artemia franciscana (brine shrimp) larvae are used as a model marine microcrustacean to assess toxicity.  Endpoints for the larvae include activation of stress responses, oxidative damage, reduced motility and death. This study provides a novel, interdisciplinary approach for rational design of surface-engineered nanoparticle-based dispersants and evaluation of their potential impacts on marine organisms.