Evaluation and Development of Aquatic Toxicity Test Methodologies

dc.contributor.advisor Otter, Ryan en_US
dc.contributor.author Beasley, Amy en_US
dc.contributor.committeemember Bailey, Frank en_US
dc.contributor.committeemember Belanger, Scott en_US
dc.contributor.committeemember Van Genderen, Eric en_US
dc.contributor.committeemember Jessen, Jason en_US
dc.contributor.department Biology en_US
dc.date.accessioned 2015-06-12T19:03:24Z
dc.date.available 2015-06-12T19:03:24Z
dc.date.issued 2015-03-26 en_US
dc.description.abstract International chemical management legislation such as the European Union's REACH (Registration, Evaluation, Authorisation, and Restriction of Chemicals) has increased the need for more and better toxicity data while recognizing the 3R's of animal use (reduction, replacement, and refinement). To address this need, the Organisation for Economic Cooperation and Development's (OECD) Fish Toxicity Framework guidance document recommended improvements to test guidelines and integrated testing strategies. This study contributes to recommendations outlined in the Fish Toxicity Framework and similar guidelines. en_US
dc.description.abstract Chapter I introduces the Embryonic Developmental Rate Assay (EDRA), a streamlined approach that uses nonlethal endpoints to assess toxicity. Time-lapse video technology was used to track the timing of seven developmental stages covering embryogenesis through hatching. Embryos exposed to two known toxicants demonstrated that developmental timing and rate were effective biomarkers for toxicity. en_US
dc.description.abstract Another refinement to test methodology is presented in Chapter II. The Stepwise Information-Filtering Tool (SIFT) is a systematic method to break down large toxicity datasets for analysis in a stepwise manner, applying user-defined criteria to address reliability and relevance. A case study application of SIFT to analysis of a chronic daphnid toxicity dataset was presented, as well as a comparison to two similar data quality methodologies. en_US
dc.description.abstract In Chapter III, the relationships between common summary statistics in toxicity testing were evaluated. The widely used hypothesis-based NOEC (No Observed Effect Concentration) has critical issues (e.g., impact of test design, no confidence levels). The ECx (Effect Concentration, with x as the percentage effect compared to controls) is regression-based, where x at a low percentage (e.g.10 or 20%) is considered an analogue to the NOEC. Using a chronic daphnid toxicity dataset, the relationship of NOEC to EC10 and EC20 and the impact of test parameters to the relationship was evaluated. en_US
dc.description.abstract Threshold of toxicological concern (TTC) concepts have been used for years to estimate `safe' concentrations for low-volume chemicals or additives, although this concept has not yet translated to ecotoxicological thresholds (ecoTTC). In Chapter IV, a comprehensive dataset was constructed, analyzed for ecoTTC values, and evaluated for the influence of chemical class, endpoint selection, and regional application factor choice. en_US
dc.description.degree Ph.D. en_US
dc.identifier.uri http://jewlscholar.mtsu.edu/handle/mtsu/4448
dc.publisher Middle Tennessee State University en_US
dc.subject Aquatic toxicology en_US
dc.subject Data quality en_US
dc.subject Hazard assessment en_US
dc.subject Risk assessment en_US
dc.subject.umi Toxicology en_US
dc.subject.umi Environmental science en_US
dc.thesis.degreegrantor Middle Tennessee State University en_US
dc.thesis.degreelevel Doctoral en_US
dc.title Evaluation and Development of Aquatic Toxicity Test Methodologies en_US
dc.type Dissertation en_US
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