Numerous chemicals have been synthesized since the Industrial Revolution. Growing evidence suggests that several classes of organic chemicals can induce or suppress hormonal activity in animals and alter their function. Biomarkers are a useful tool to quantify the biological effect of chemicals on animals. This study was designed to screen male and female American alligators collected from a known contaminated site, Lake Apopka, from a new site near Kennedy Space Center, Merritt Island National Wildlife Refuge, and a reference site, Lake Woodruff National Wildlife Refuge for disruptions in physiological processes. Our lab tested hepatic lactate dehydrogenase (LDH) (male only), glutathione-S-transferase (GST), and metallothionein (MT) for alterations in anaerobic respiration, chemical detoxification, and heavy metal sequestration, respectively. We found higher LDH activity in samples from Lake Apopka, suggesting more anaerobic respiration and energetic stress compared to the other two sites. Metallothionein levels were induced at Lake Apopka and Merritt Island NWR, suggesting possible elevated heavy metal exposure. Contrary to expectations, GST activity from Lake Apopka was not significantly different from Lake Woodruff. But various chemicals, like polyaromatic hydrocarbons or organophosphates, can induce or suppress GST activity, respectively. Metallothionein induction and GST suppression at Merritt Island NWR are consistent with another study from our lab. These biomarkers may indicate that alligators from Lake Apopka and Merritt Island have altered physiology.

Screening American Alligators, Alligator mississippiensis, Inhabiting Reference and Contaminated Sites for Alterations In Normal Physiological Function.