Civil Engineering ETDs

Publication Date

Summer 7-12-2022


We investigated the adsorption, precipitation, and phytoavailability of uranium after reactions with soil, high-density polyethylene particles, and Mentha arvensis through the integration of batch experiments, plant exposure, microscopy, and spectroscopy. Soluble U (initially 100 µM) decreased by 98.6% (1.09 µM) at pH 5 and 86.2% (13.81 µM) at pH 7.5 after 0.1 h of reaction with 10 g of soil in solution. Heterogenous U precipitates were observed in weathered HDPE surfaces for experiments without soil at both pH conditions. This suggests the weathering of the microplastic surfaces enhanced the nucleation of the U precipitates. Plants exposed to both U and HDPE exhibited photosynthetic rates 76.3% lower and transpiration rates 86.6% lower than plants not exposed, possibly due to negative synergetic interactions of U and HDPE. These results give insight into the surface-controlled reactions of soluble U with microplastics, soils and plants which is relevant to environments in which those co-occur.


heavy metals, microplastics, soil, adsorption, precipitation, uranium

Document Type


Degree Name

Civil Engineering

Level of Degree


Department Name

Civil Engineering

First Committee Member (Chair)

Dr. Eliane El Hayek

Second Committee Member

Dr. José Cerrato Corrales

Third Committee Member

Dr. Kerry Howe