Ultrastructural alterations in the ventricular myocardium of the adult italian newt (Lissotriton italicus) following exposure to nonylphenol ethoxylate

Nonylphenols ethoxylates (NPEs) are surface active agents (surfactants) commonly used in cleaning products, in industrial processes, agricultural formulations and paints. They are found in sewage, municipal wastewaters and industrial effluents, and as contaminants in water bodies. Accumulating data suggest that exposure to NPEs can adversely affects functional properties of the neurologic, reproductive, immune, and endocrine systems. In order to examine whether NPEs exert similar damaging effects on the cardiovascular system, we used an amphibian model to examine the ultrastructural alterations of the ventricular myocardium following exposure to NPEs. Adult Lissotriton italicus in the aquatic phase were exposed to NPE10 (100 μg/L, ppb) for 96 h. Heart specimens were collected from a total of 10 individuals and processed for scanning and transmission electron microscopy. Our ultrastructural examinations demonstrated that amphibian ventricle is susceptible to the effects of NPEs. The most pronounced alterations were observed in the membrane compartments of both myocardial and endothelial cells as demonstrated by the presence of swollen mitochondria with disrupted cristae and dilated rough endoplasmic reticulum. We suggest that destabilization of the lipid milieu within membranes might represent one of the potential mechanisms by which NPEs exert their toxic effects on amphibian heart.