School of Health Sciences
Biology: Environmental Science
Herbicide, Cambarus sp., Crayfish, GGT, Toxicology
Environmental Health | Toxicology
Wickham, Amelia, "The Sublethal Response of Cambarus sp. to Acute Low Dose Herbicide Exposure Evidenced by a Change in GGT Levels and Apoptosis" (2022). Senior Honors Theses. 1185.
Following application, herbicidal runoff can collect in freshwater ecosystems, briefly exposing non-target organisms. As biological indicators, crayfish serve as models to assess freshwater health. Chemically stressed crayfish form reactive oxygen species (ROS) which are neutralized by the glutathione pathway. As glutathione depletes, γ-glutamyl-transferase (GGT) upregulates to increase glutathione formation. High oxidative stress lowers glutathione levels and subsequent apoptosis occurs. For this acute study, crayfish were exposed to 5ppb and 50ppb of atrazine, glyphosate, and 2,4-D. Herbicide exposures were expected to induce higher GGT production, increased oxidative stress, and increased apoptosis. Instead, GGT and apoptosis predominately decreased relative to the control. This suggests that oxidative damage was mitigated because the crayfish were able to effectively neutralize ROS at 5 and 50ppb.