Honors College

Document Type

Honors Thesis

Publication Date

Spring 5-2017


Exposure to environmental pollutants is considered to be detrimental to the larval development of various fish species. The liver is thought to be a target organ for many chemicals because of its high lipid content which bioaccumulates lipophilic contaminants. Common impacts of dioxins found in fish livers include lipidosis and glycogen depletion. However, very few studies have been conducted to show these developmental issues in the early stages of long-lived species such as sturgeon. Given their bottom dwelling nature, sturgeon are more vulnerable to environmental pollutants such as dioxin which have long half-lives in aquatic sediments. This study sought to determine the impacts of the persistent organic pollutant, dioxin, on the hepatic development of the 25 larval shortnose sturgeon (Ascipenser brevirostrum). The average area and numbers of vacuoles located in livers of larval sturgeon exposed to different dioxin concentrations including 50 ppb, 0.5 ppb, and 0.005 ppb, as well as a treatment (water) and a vehicle (acetone) control, were examined. There were no significant differences between the concentration of dioxin exposure and the average area and numbers of vacuoles in the livers of larval sturgeon examined in this study. In the future, larger sample sizes should be used to determine the effects of dioxin on liver development and other organs should be examined to determine overall developmental impacts.