lead 1

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 (Pb) [led]
a chemical element, atomic number 82, atomic weight 207.19. Excessive ingestion or absorption causes lead poisoning. (See also Appendix 6.)
l. poisoning poisoning caused by the presence of lead or lead salts in the body; it affects the brain, nervous system, blood, and digestive system and can be either chronic or acute. Called also plumbism and saturnism.
Chronic Lead Poisoning. This was once fairly common among painters, and was called “painter's colic.” It became less frequent as lead-free paints were substituted for lead-based ones and as plastic toys replaced lead ones. The disease is still seen among children with pica (a craving for unnatural articles of food) who may eat lead paint chips or coatings. The Centers for Disease Control and Prevention defines an elevated blood lead level as >10 μg/dL for children younger than six years of age. However, there is evidence that there are subtle effects even at lower levels

Symptoms include weight loss, anemia, stomach cramps (lead colic), a bluish black line at the edge of the gums, and constipation. Other symptoms may be mental depression and, in children, irritability and convulsions. In addition to the poisoning, the anemia and weight loss must also be treated, usually by providing an adequate diet. In serious cases, EDTA (calcium disodium edetate) may be prescribed.
Acute Lead Poisoning. This rare condition can be caused in two ways: lead may accumulate in the bones, liver, kidneys, brain, and muscles and then be released suddenly to produce an acute condition; or large amounts of lead may be inhaled or ingested at one time. Symptoms are a metallic taste in the mouth, vomiting, bloody or black diarrhea, and muscle cramps. Diagnosis is made by examination of the blood and urine.
Treatment. Immediate removal of unabsorbed lead in the intestinal tract through the administration of mild saline cathartics and enemas. EDTA is given and in most cases measures must be taken to reduce the increased intracranial pressure that accompanies acute lead poisoning.
Prevention. An awareness of the prevalence of lead poisoning among children of preschool age who live in poorly maintained housing has led to neighborhood screening surveys in high-risk areas.

An important aspect of prevention of lead poisoning is determination of sources of lead in the environment and efforts to remove them. Sources include peeling paint from window sills, walls, floors, and bannisters, and from soil around old houses that have shed exterior paint through the years. An often unsuspected source is the glaze of certain pottery and “leaded glass;” lead can leach out into food and beverages from such vessels. A vital factor in coping with the problem of lead contamination is public education and development of a community awareness of possible sources and of the need for elimination of these hazards from the environment.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.