Acute toxicity of sodium fluorescein to ashy pebblesnails fluminicola fuscus

Abstract

Groundwater scientists use fluorescein dyes to trace ground water resources that supply springs which may contain threatened or endangered mollusk species. To estimate risks of a commonly used groundwater tracer to the threatened Bliss Rapids snail Taylorcocha serpenticola we tested the toxicity of sodium fluorescein solutions to a surrogate species, the ashy pebblesnail Fluminicola fuscus. Trials were conducted in static 24-h exposures to several levels of treatment as well as controls with no sodium fluorescein at temperatures similar to those in the habitat of concern. We estimated 377 mg L-1 as the median lethal concentration for the ashy pebblesnails. Using these data, we concluded that risks to mollusks from the proposed groundwater testing were likely low.