Date of Award
2-9-2023
Document Type
Thesis
Degree Name
Environmental Sciences, MS
First Advisor
Jennifer Bouldin
Committee Members
Averi Fegadel; Brook Fluker; Richard Lizotte
Call Number
LD 251 .A566t 2022 L93
Abstract
Ceriodaphnia dubia is an EPA-recommended organism used in regulatory toxicity testing of surface waters and commercial chemicals. They are often cultured for extended periods in the laboratory with little knowledge of how it impacts subsequent generations. This thesis investigated if C. dubia cultured for an extended period were representative of three recently-collected field populations by comparing their culturing characteristics and sensitivities to toxicants. Comparative chronic toxicity tests with sodium chloride, the neonicotinoid insecticide thiamethoxam, and mixtures of the two toxicants measured differences in sensitivities among the laboratory and field cultures, specifically in the variability of responses. For culturing characteristics, the laboratory culture had longer body lengths, more neonates, and lower mortality rates than the field populations of C. dubia. These differences suggest that replacing laboratory cultures with field organisms periodically to ensure the environmental relevance of toxicological studies is not realistic under the existing EPA methodology.
Rights Management
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Lydy, Victoria Rose, "Comparing the Toxicant Responses and Culturing Characteristics of Long-Term Laboratory-Reared and Field Populations of Ceriodaphnia dubia" (2023). Student Theses and Dissertations. 213.
https://arch.astate.edu/all-etd/213
