Realistic Levels of a Fertilizer Impair Iberian Newt Embryonic Development

Abstract

Abstract: A wide variety of agricultural chemicals with potential to affect amphibian health are released into the environment daily. Most of these chemicals are xenobiotic compounds that are highly toxic to embryos, tadpoles, and terrestrial stages. Other substances that occur in pristine environments at harmless concentrations, such as inorganic nitrogenous compounds, may reach potentially toxic levels as a consequence of certain human activities, including the application of fertilizers. Most of the studies that analyze the effects of inorganic nitrogen on amphibian embryos are conducted with anurans, whereas little information exists regarding urodeles. Embryos of newts and salamanders usually exhibit longer times to hatch than frogs and toads. A longer hatching time results in a longer exposure of embryos to diffuse environmental pollution and therefore a higher risk of suffering toxic effects during the embryonic stage. We demonstrate that ammonium nitrate, a widely used nitrogenous fertilizer, at ...