Science Serving Maryland's Coasts

Kimberly Hohlweg, Pennsylvania State University

Class Year: 

Project Title: 

Sub-Lethal Effects of Polybrominated Diphenyl Ethers (BDEs) on DNA Integrity and Gonadal and Thyroid Structure of Snapping (Chelydra serpentina) and Red-Eared Slider Turtles (Trachemys scripta)


Polybrominated diphenyl ethers (BDEs) have been used for years as flame retardants in plastics, electronic equipment, and textiles. It has been found that BDEs can leach from these materials and contaminate terrestrial and aquatic ecosystems. Once in the environment, BDEs bioaccumulate in sediments and tissue, but it is not clear what harmful effects this accumulation has on exposed individuals. Studies have shown that BDEs potentially act as endocrine-disrupting compounds and estrogen mimics; there is also a possible link between BDEs and single-strand breaks in DNA. This study, therefore, sought to investigate these three potential effects of BDEs on snapping and red-eared slider turtles. A significant difference was found in the number of DNA single-strand breaks between those snapping turtles fed BDE-99 contaminated food and the negative control. A species difference was also found in which BDE-47 and BDE-99 contaminated snapping turtles showed significantly more DNA damage than BDE-47 and BDE-99 contaminated red-eared slider turtles, respectively. The results of both the thyroid and gonadal studies showed no significant differences among treatment groups. Further investigations of other species and endpoints are required to comprehensively evaluate threats of BDEs to wildlife.