The Possibility of Occult Lead Poisoning

Abstract

To the Editor: In their review of anemia in the elderly, Steensma and Tefferi underestimate the importance of lead poisoning.1Steensma DP Tefferi A Anemia in the elderly: how should we define it, when does it matter, and what can be done?.Mayo Clin Proc. 2007; 82: 958-966Abstract Full Text Full Text PDF PubMed Scopus (97) Google Scholar Lead-containing hair dyes, available over-the-counter in most drugstores, can cause anemia in the elderly due to transdermal absorption. This possible chronic toxic effect from absorption of lead is increased if the skin is irritated. The hair dye labels advise that the product should not be applied to irritated skin. However, people who use these products to appear younger by coloring gray hair probably ignore this warning, as well as warnings about frequency of use. The success of this hair-coloring product depends on repeated applications. In my experience, the topic of hair dye is often considered “off limits” or overlooked when physicians examine patients and elicit medical histories. If physicians recognize this occult possibility in their patients, perhaps lead poisoning could be eliminated from the differential diagnosis of anemia in the elderly and the resulting sequelae. The best-known and studied toxic effects of lead poisoning occur in heme synthesis. Recently the media have drawn attention to the exposure of lead in toys imported from China.2Lipton ES Barboza D As more toys are recalled, trail ends in China. New York Times.http://www.nytimes.com/2007/06/19/business/worldbusiness/19toys.htmlDate: June 19, 2007Google Scholar Lead paint in older houses in the United Sates has long been recognized as an environmental hazard. Oral ingestion of lead-based paint is serious in young children and represents most cases of lead poisoning in this age group. In adults, the presenting symptoms can be attributed to other factors, and the possibility of lead toxicity is often overlooked, especially in older men. Adult men are also at risk of lead toxicity because of occupational exposure. Most toxic effects of non-lead-containing hair dyes for women are related to accumulative abuse, with scalp scarring and damage to the hair shafts. On a recent trip to China, I found it disturbing that young and adult Chinese people in the cities were using lead-based hair dyes to make their hair darker to mimic Western fads. Media attention has encouraged some Chinese manufacturers to omit the labeling of lead content in these products. In adult patients, multisystem disease due to lead toxicity should be considered when symptoms and signs are abdominal pain, hemolytic anemia, neurologic dysfunction (mononeuropathy including headache), gout, or renal insufficiency. Questions about hair dyes need to be included in the medical history. The Possibility of Occult Lead Poisoning–ReplyMayo Clinic ProceedingsVol. 83Issue 3PreviewWe thank Dr Brown for drawing attention to an unusual cause of anemia that can affect elderly persons. Although the magnitude of risk from hair dyes is uncertain,1–3 environmental exposure to lead is common enough that lead intoxication should routinely be considered in the differential diagnosis of unexplained anemia, especially in patients from outside the United States.4 In addition to the paint and toys mentioned by Dr Brown, nonoccupational sources of lead exposure have included ceramic glazes5 (a potential danger for nursing home residents participating in ceramic arts programs6), traditional medicines,7 cosmetics (especially kohl-based eyeliner8), candy,9 metal lunchboxes,10 and several others. Full-Text PDF