AMELIORATIVE EFFECT OF RESVERATROL ON LEAD-INDUCED ORGAN TOXICITY IN WISTAR RATS
CHAPTER ONE
1.0 INTRODUCTION
1.1 Background
Lead is a heavy, low melting, bluish-gray metal that occurs naturally in the Earth’s crust. However, it is rarely found naturally as a metal. It is usually found combined with two or more other elements to form lead compounds. For these reasons, lead has been used by humans for millennia and is widespread today in products as diverse as pipes, storage batteries, pigments and paints, glazes, vinyl products, weights, shot and ammunition, cable covers, and radiation shielding. Tetra-ethyl lead was used extensively from the 1930s to the 1970s as a petrol additive to improve engine performance (Rosner and Markowitz, 1985; Landrigan et al., 2002). Tetra-ethyl lead has been eliminated from the petrol supplies of the majority of countries, but is still used in about nine countries (UNEP, 2008).
Lead poisoning (also known as Plumbism, Colica Pictonum, aturnism, Devon colic, or painter’s colic) is a medical condition in humans and other vertebrates caused by increased levels of the heavy metal lead in the body (Washington, 2011). Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, reproductive and nervous systems. It interferes with the development of the nervous system and is therefore particularly toxic to children, causing potentially permanent learning and behaviour disorders. Symptoms include abdominal pain, confusion, headache, anemia, irritability, and in severe cases seizures, coma, and death (Washington, 2011).