https://doi.org/10.53550/EEC.2026.v32.i02s.056
NOTE: All amphibian metamorphosis is under thyroid hormone control.
Abstract
Fluoride contamination of aquatic ecosystems from industrial, agricultural, and anthropogenic activities poses risks to aquatic organisms, particularly amphibians with permeable skin and dual phases of life cycle. The present study investigated the chronic sublethal effects of sodium fluoride (NaF) exposure (1, 5, 10, and 50 mg/L) on the survivability, growth, and development of Polypedates maculatus tadpoles over 28 days under laboratory conditions. Tadpoles exposed to increasing NaF concentrations showed significant, concentration- and time-dependent increases in mortality, reductions in total length, snout-vent length, and body weight, and delayed or failed metamorphosis compared with control tadpoles. These findings highlight fluoride as a potent developmental toxicant in amphibians and underscore the need for monitoring and regulating fluoride levels to protect amphibian populations and freshwater ecosystem health.