Acute effects of road de-icers on the tadpoles of three anurans

Abstract

The application of road de-icing compounds during the winter has the potential to result in the contamination of nearby freshwater habitats and affect amphibians breeding in those habitats. We conducted a study of the effects of several de-icing and associated compounds (sodium chloride, magnesium chloride, calcium acetate, magnesium acetate, sodium ferrocyanide, and sodium formate) on the tadpoles of three species of anurans: African clawed frogs (Xenopus laevis), American toads (Bufo americanus), and green frogs (Rana clamitans). The survivorship of X. laevis tadpoles was negatively affected by MgCl2, but not by NaCl. The survivorship of R. clamitans tadpoles was negatively affected by both NaCl and MgCl2. The tadpoles of B. americanus were not affected by the concentrations of NaCl and MgCl2 used in this study. Our results suggest that contamination of freshwater habitats by de-icing and associated compounds could potentially adversely affect at least some anuran populations, but that this potential can vary from species to species, and from compound to compound.