Evaluation of Phosphate Toxicity in Cope's Gray Treefrog (Hyla chrysoscelis) Tadpoles

Abstract

Phosphate pollution is a widespread problem resulting from agricultural runoff and urban wastewater. Phosphates are known to cause eutrophication and algal blooms, but little is known about phosphate toxicity, particularly among amphibians. To investigate possible phosphate toxicity, Hyla chrysoscelis tadpoles were exposed to concentrations ranging from 0–200 mg/L PO4-P for 15 days. Phosphate was found to have no effect on the survival, growth, or developmental stability of the tadpoles, indicating that phosphate may not be toxic to this species at levels associated with anthropogenic inputs. Phosphate was found to increase the pH of the test water, which, in conjunction with other stressors, may have negative effects within aquatic communities. However, phosphate could also affect anuran tadpoles positively by increasing algal food resources. Because phosphate is a ubiquitous pollutant, further testing using more complex experimental designs is warranted.