04/12/2021
By Christianto Putra
The defense will be held on April 26 at 2 p.m. via Zoom. Please contact Kelsey Mangano for meeting information if you are interested in attending. The committee will be composed of Kelsey Mangano (Chair), Dhimiter Bello, Katherine Tucker and Shannon Kelleher. A brief abstract is provided below.
Engineered nanomaterials are used in food products for a variety of reasons including improving or maintaining texture, flavor, color, consistency, and even visual acceptability. Humans are exposed to various engineered nanoparticles daily, including titanium dioxide (TiO2 or E171) via food products; these are, but not limited to, sweets, chewing gums, and non-dairy coffee/tea creamers. It is primarily used as a coloring agent and whitening agent due to its brightness, high refractive index, and resistance to discoloration. E171 consists of both TiO2 nanoparticles and non-nanoparticles. Studies have shown that nano-TiO2 can bioaccumulate in various human organs and potentially cause various adverse outcomes such as inflammation, genotoxicity, carcinogenicity, developmental toxicity, and cardiovascular toxicity. At present, it is not possible to discern the effects of the nanoscale fraction from the microscopic particles; therefore, this distinction is, for all practical purposes, theoretical. Some regulatory agency banned the use of E171 due to health concerns, while others continue the use it due to the lack of evidence supporting the risks of chronic exposure. The global objective of this thesis was to estimate dietary TiO2 among young adults in the United States. The current estimate of dietary exposure of TiO2 was relatively close to past studies conducted in a different population. Worth noting that in this current study, most of the current participants were consuming relatively lower amounts of TiO2 (positively skewed) and that the level of TiO2 in some foods are highly dependent on brands; therefore, an updated database and improvement on dietary collection method would be needed to accurately account the usual consumption of TiO2 in U.S. population. Lastly, the higher-levels of TiO2 in stools were found to be associated with elevated fecal alpha-1-antitrypsin (biomarker for intestinal permeability) but not fecal calprotectin or lactoferrin (gut inflammatory biomarker). While the amount of TiO2 was linked to more permeable gut, further research is needed to elucidate the absence of inflammatory response. This study highlighted the importance of future research to understand the dietary exposure and health implications of food additives containing nanoparticles such as E171.