This work concentrates on cellular and molecular toxicity of selected well-known drugs or chemicals on the cardiovascular system. The primary objective is to provide a better understanding of the mechanisms by which xenobiotics are toxic to mammalian tissues and cells. The use of in vitro cellular and tissue systems provides attractive experimental models to assess toxic manifestations of xenobiotics. This work addresses the most recent findings on the cellular and molecular mechanisms of toxicity of several important cardiotoxic agents: doxorubicin, ethanol, cocaine, and the catecholamines. It presents an overview of vascular toxins and their biochemical effects. Included is a summary of in vitro cardiovascular techniques for assessing toxicity of xenobiotics. This publication is important for those in toxicology, tissue culture, pharmacology, in vitro toxicology, developmental biology and related areas.