Growth and development of tadpoles (Xenopus laevis) exposed to selective serotonin reuptake inhibitors, fluoxetine and sertraline, throughout metamorphosis.

Selective serotonin reuptake inhibitors (SSRIs) are widely prescribed drugs that are present in sewage effluents and surface waters. The objective of the present study was to determine whether low environmentally relevant concentrations of the SSRIs fluoxetine and sertraline could impair growth and development in tadpoles of the African clawed frog (Xenopus laevis) and to evaluate if such effects may be caused by a disruption of the neuroendocrine system. Tadpoles were exposed to SSRIs at concentrations of 0.1, 1, and 10 microg/L for 70 d throughout metamorphosis. No effects on deformities were observed. Tadpoles exposed to fluoxetine (10 microg/L) and sertraline (0.1, 1, and 10 microg/L) exhibited reduced growth at metamorphosis. Tadpoles exposed to sertraline (0.1 and 1 microg/L) exhibited an acceleration of development as indicated by an increase in the time to tail resorption. The effects of SSRIs on growth and development in tadpoles were likely driven by reduced food intake. Reduced feeding rates were observed in SSRI-exposed tadpoles, and nutritional status can influence growth and development in amphibians via effects on the neuroendocrine system. Only sertraline was capable of causing developmental toxicity in tadpoles at environmentally relevant concentrations. These data warrant additional research to characterize the risks to human health and wildlife from pharmaceutical exposures.