Dissertation Research 

A view of the city of Camden, NJ

Sources of Microplastics in Urban Soils

With projections that more than half of the global population will live in cities by 2050, it is paramount we understand how we can preserve the green spaces that provide numerous mental and physical health benefits. In order to understand how microplastics may affect those spaces, we need  to understand what types of microplastics do we find in urban soils that have different drainage area characteristics? How does land use influence what we find? One of my dissertation research projects aims to understand sources of microplastics in the urbanscape. This information can further inform us on what material changes we can make, especially in urban environments, as well as understand what ecosystem services are vulnerable to microplastic pollution in urban soils. Part of this work requires me to create a validated and reproducible method to extract and quantify microplastics in different field soils with varying textures and characteristics.

Timnit coring soil at Coal Oil Point Reserve in Goleta, CA

Pathways and Fates of Microplastics in Urban Soils

In efforts to understand what solutions we need to limit microplastic flows, we need to consider how different variables like shape, size and plastic type influence their movement (and potential exposure to different organisms). So I ask the following questions in my work: How do the size, shape and type of microplastics contribute to their distribution and deposition in soils? How can we limit microplastic movement in the urbanscape? One of my dissertation research projects seeks to understand how microplastics move into urban soil systems through stormwater runoff and how we can leverage natural treatment systems, such as biofilters, as a solution via a field-scale study in Southern California.

A view of the Santa Barbara beachfront

Plastic Fates in Marine Sediments

 What happens to plastics, however, when they have other fates that are not soil, like the ocean? Plastics do not always float and can sink. As they sink, they can either be consumed or end up buried in the sediment. What happens to them when they are in sediments? Do they degrade or remain dormant? Part of my dissertation research focuses on understanding the fate of different plastic polymer types in ocean sediments by looking at changes to the chemistry and surfaces of the plastics.

Other Projects

A view of the Santa Barbara landscape

Synthetic microfiber emission pathways due to apparel washing in 2016. 

Understanding Stormwater's Role in the Conveyance of Microplastics into Santa Barbara's Coastal Waters 

I am co-leading a project with my colleague, Becca Reynolds and intern, Roger Nguyen, in collaboration with the City of Santa Barbara which seeks to understand the concentration of microplastics conveyed by stormwater from the urbanscape into Santa Barbara's coastal waters. Our project seeks to further understand what mitigation measures can be implemented such as street sweeping and catch basins to limit microplastic flows. Project is funded by the UCSB Coastal Fund and Santa Barbara Creeks Division. 

Quantification of Synthetic Microfiber Emissions into the Environment

I partook in an interdisciplinary project focused on assessing the role of laundering in synthetic microfiber emissions into the environment by conducting a global material flow analysis. This study highlighted how we overlook microfiber flows into terrestrial environments, despite them being  almost equivocal to what enters marine environments. Project was funded by the H. William Kuni Interdisciplinary Fellowship, Purnell, Ocean Conservancy & Outdoor Industry Association.  Featured in BBC and other media outlets.