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Epidemiologic Notes and Reports Selenium Intoxication -- New York

On December 27, 1983, a 57-year-old female in New York began taking a daily selenium supplement distributed by Brite Years, Inc., of Tempe, Arizona. The label on the 90-tablet bottle recommended taking one of the 150-mcg tablets daily. She took the prescribed number in addition to her usual daily vitamins, which included: vitamin C (1,000 mg, plus bioflavinoids, thrice daily); vitamin A (10,000 units once daily); vitamin D (400 units once daily); vitamin E (400 units once daily); B complex (once daily); and a high-potency mineral supplement labeled as containing all 72 trace elements in undefined quantities, as well as calcium, magnesium, phosphate, potasium, zinc, iron, manganese, and iodine. She consumed at least one vitamin C tablet (1,000 mg) simultaneously with the selenium supplement.

Approximately 11 days after starting the selenium supplement, the patient noted marked hair loss limited to her scalp, which progressed over a 2-month period to almost total alopecia. Two weeks later, she noted white horizontal streaking on the fingernail of her left fifth digit, tenderness and swelling on the fingertip, and purulent discharge from the fingernail bed. This progressed over a 3-week period to involve all fingernails. The patient subsequently lost the entire fingernail of her left fifth digit. In addition, she experienced periodic episodes of nausea and vomiting, a sour-milk breath odor, and increasing fatigue. In January, she consulted a dermatologist for her hair loss and nail changes and was treated with oral erythromycin for paronychia. Her alopecia was attributed to emotional stress following the death of her husband a year earlier.

On March 11, 1984, she heard on the radio that the selenium tablets distributed by Brite Years, Inc., were being recalled because of superpotency. She stopped taking the tablets and consulted her internist. She had consumed 77 of the 90 tablets. A serum selenium level from March 15 was reported as 528 ng/ml, approximately four times the normal levels for the U.S. population (1).

The distributor voluntarily recalled the product when analysis of the selenium tablets from one lot revealed a selenium level of 27.3 mg per tablet (182 times higher than labeled). The implicated tablets were reportedly manufactured by Superior Health Vitamin and Health Foods in Deer Park, New York, for the distributor. These tablets were part of approximately 250 bottles distributed to 39 accounts in 15 states (Alaska, Alabama, Arizona, Arkansas, California, Iowa, Missouri, Montana, New York, Ohio, Oregon, Pennsylvania, Texas, Utah, and Virginia) from four distribution lots (codes 012163, 016213, 301216, and 012161). Subsequent analyses of tablets from all four implicated distribution lots have contained 25 mg of sodium selenite and 4 mg-5 mg total of elemental and/or organic selenium. Analysis of tablets taken from the symptomatic woman in New York found 31 mg of total selenium per tablet. Reported by R Jensen, DO, W Closson, PhD, Brunswick Hospital, Amityville, R Rothenberg, MD, State Epidemiologist, New York State Dept of Health; Emergency and Epidemiological Operations Br, Brooklyn District Office, U.S. Food and Drug Administration; Cancer Prevention Studies Br, Div of Cancer Prevention and Control, National Cancer Institute; Office of the Director, Epidemiology Program Office, CDC.

Editorial Note

Editorial Note: Selenium is widely, though irregularly, distributed in soil, forages, and grains and has many commercial uses. Human intake of selenium comes mainly from cereal, fish, and meat in the diet, and, in residents of one city studied, averaged 81 mcg per day (2). While there is no established recommended daily allowance, the proposed adequate and safe intake of selenium in adults is 50 mcg-200 mcg daily (3). Until lately, there were no well-documented cases of human selenium toxicity. A recent study reported a number of villages in the People's Republic of China, where high percentages of individuals had nail and hair loss, dermatitis, nausea, garlic odor on their breath, fatigue, irritability, and hyperreflexia (4). Individual daily dietary selenium intake in this area ranged from 3.20 mg to 6.69 mg (average 4.99 mg), and whole blood levels of selenium ranged from 1,300 ng/ml to 7,500 ng/ml (average 3,200 ng/ml).*

The signs and symptoms exhibited by the New York woman were almost certainly due to selenium intoxication. The estimated cumulative dose of selenium she ingested over the 77 days was 2,387 mg. Her toxicity was probably minimized by the simultaneous ingestion of large doses of vitamin C. Vitamin C reduces selenite to elemental selenium that is poorly absorbed.

This incident demonstrates that excessive doses of trace elements can have toxic effects. Implementation of improved quality-control measures in the manufacture of these food supplements could help alleviate problems of this nature in the future. With the general increase in use of vitamin and mineral supplements in this country, the public and the medical community should be aware of the potential for toxicity.


  1. Levander OA. Unpublished data.

  2. Welsh SO, Holden JM, Wolf WR, Levander OA. Selenium in self-selected diets of Maryland residents. J Am Diet Assoc 1981;79:277-85.

  3. Committee on Dietary Allowances, Food and Nutrition Board. Recommended dietary allowances. Ninth revised edition, 1980. National Academy of Sciences, Washington, D.C., p. 162

  4. Yang G, Wang S, Zhou R, Sun S. Endemic selenium intoxication of humans in China. Am J Clin Nutrition 1983;37:872-81. *Whole blood selenium measurements are approximately 30% higher than serum selenium.

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