B.S., Chemistry, Clemson University 2009
Currently, I am studying the effects of TiO2 NPs on polycyclic aromatic hydrocarbon (PAH) mixture toxicity to fish under environmentally relevant conditions. Titanium dioxide nanoparticles (TiO2 NPs) are commonly used as a photocatalyst and as a UV-attenuator in products such as sunscreens, plastics, and cleaning solutions due to their photo-reactive properties. In addition, they are being heavily investigated for use as a remediation aid at sites contaminated with organic compounds such as pesticides, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs). When exposed to UV light, TiO2 NPs catalytically oxidize PAHs to degradation products such as quinines, ketones, and alcohols. This change in the degradation profile of PAHs could result in altered AhR related toxicity. In addition, TiO2 NP and some PAHs are phototoxic via photosensitization, thus, co-exposure could result in additive or synergistic oxidative stress-related toxicity. TiO2 NP may also have the ability to alter uptake of xenobiotics. All of these processed will be affected by natural environmental variables such as UV light and natural organic matter. To date, no studies have addressed whether this process effectively reduces the toxicity of PAH mixtures, if the TiO2 NPs could have additive or synergistic toxicity with the PAHs, or if the TiO2 NPs could alter uptake of the PAHs. My research encompasses two goals, 1) Determine how TiO2 NPs affects the toxicity of Elizabeth River sediment extract (ERSE), a complex mixture of PAHs, under the influence of artificial sunlight in early life stage zebrafish (Danio rerio), and 2) Determine how TiO2 NPs affects toxicity and degradation of PAH mixtures in environmentally complex media using simulated freshwater wetland mesocosms.