All ETDs from UAB

Advisory Committee Chair

Robert Angus

Advisory Committee Members

William Howell

Coral Lamartiniere

Douglas Watson

Stephen Watts

Document Type


Date of Award


Degree Name by School

Doctor of Philosophy (PhD) College of Arts and Sciences


Estrogenic compounds of anthropogenic origin enter the environment from several different sources, including domestic wastewater and agricultural runoff. Natural estrogens, synthetic estrogens, and estrogen breakdown products have been identified in wastewater treatment plant (WWTP) effluents. These compounds have direct and indirect effects on the endocrine systems of organisms living in the receiving waters. Male mosquitofish (Gambusia affinis) have been suggested as model bioindicator organisms for endocrine disruption by estrogenic compounds for a variety of reasons, including their hardiness, broad environmental tolerances (including temperature, salinity, and dissolved oxygen), widespread geographical distribution, and ease of use in the laboratory. We examined two potential biomarkers of endocrine disruption by estrogenic compounds: variation in sperm counts and the induction of the normally female-limited protein vitellogenin (VTG) in males. We demonstrated that males living below a WWTP effluent exhibited significantly decreased mean sperm counts compared to males living in a reference site, males exposed to a synthetic estrogen in the laboratory had significantly lower mean sperm counts than untreated males, and that there was a significant negative correlation between mean sperm count and dose of synthetic estrogen. We also examined aniii nual sperm counts in males living in an undisturbed environment and found that there was no significant variation in monthly mean sperm counts. However, data analysis demonstrated that mean sperm count showed a significant positive correlation to water temperature. Finally, we demonstrated that there is significant effect of temperature on the amount of VTG mRNA and protein produced by males exposed to a synthetic estrogen in the laboratory.



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.