Semester of Graduation
Spring 2026
Degree Type
Dissertation/Thesis
Degree Name
Master of Science in Integrative Biology
Department
Department of Molecular and Cellular Biology
Committee Chair/First Advisor
Dr. Andrew D. Haddow
Second Advisor
Dr. Marina C. Koether
Third Advisor
Dr. Nicholas S. Green
Abstract
Per- and polyfluoroalkyl substances (PFAS) have been used in both consumer and commercial manufacturing since the 1950’s and are persistent environmental pollutants because of their degradation-resistant nature. They primarily enter the environment via runoff water from manufacturing plants, fire-fighting training facilities, and airports. During their immature stages, mosquitoes are fully aquatic and therefore at high risk of exposure to PFAS-contaminated surface water. This thesis investigated the combined effects of exposure to perfluorooctanesulfonic acid (PFOS), a frequently detected PFAS in the environment, and environmental stressors, such as suboptimal nutrition and overcrowding, on the development of Aedes aegypti. Immature stage PFOS exposure alone was found to significantly decrease total emergence (F(1,355), = 314.480, p < 0.001) and wing length (F(4,653) = 27.650, p < 0.001). A median lethal concentration (LC50) and an LC25 were estimated to be 203.9 µg/L and 143.2 µg/L, respectively. While density did not impact development or survival, suboptimal nutrition caused development delays, with the overcrowded density (1 larvae/mL, 300 larvae) taking 2.5 times longer to reach 50% emergence than the control (0.1667 larvae/mL, 50 larvae). When Ae. aegypti were exposed to PFOS while overcrowded, increased total emergence was observed when compared to the control. Significant emergence delays (p < 0.001) were observed both alone and in tandem with PFOS exposure when Ae. aegypti experienced limited resource availability. These findings revealed that environmental stressors are able to significantly alter the impacts of PFOS exposure, which could impact mosquito population dynamics and vectorial capacity.