MacFarquhar Jennifer K, Broussard Danielle L, Melstrom Paul, Hutchinson Richard, Wolkin Amy, Martin Colleen, Burk Raymond F, Dunn John R, Green Alice L, Hammond Roberta, Schaffner William, Jones Timothy F
Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Arch Intern Med. 2010 Feb 8;170(3):256-61. doi: 10.1001/archinternmed.2009.495.
Selenium is an element necessary for normal cellular function, but it can have toxic effects at high doses. We investigated an outbreak of acute selenium poisoning.
A case was defined as the onset of symptoms of selenium toxicity in a person within 2 weeks after ingesting a dietary supplement manufactured by "Company A," purchased after January 1, 2008. We conducted case finding, administered initial and 90-day follow-up questionnaires to affected persons, and obtained laboratory data where available.
The source of the outbreak was identified as a liquid dietary supplement that contained 200 times the labeled concentration of selenium. Of 201 cases identified in 10 states, 1 person was hospitalized. The median estimated dose of selenium consumed was 41 749 microg/d (recommended dietary allowance is 55 microg/d). Frequently reported symptoms included diarrhea (78%), fatigue (75%), hair loss (72%), joint pain (70%), nail discoloration or brittleness (61%), and nausea (58%). Symptoms persisting 90 days or longer included fingernail discoloration and loss (52%), fatigue (35%), and hair loss (29%). The mean initial serum selenium concentration of 8 patients was 751 microg/L (reference range, < or =125 microg/L). The mean initial urine selenium concentration of 7 patients was 166 microg/24 h (reference range, < or =55 microg/24 h).
Toxic concentrations of selenium in a liquid dietary supplement resulted in a widespread outbreak. Had the manufacturers been held to standards used in the pharmaceutical industry, it may have been prevented.
硒是正常细胞功能所必需的元素，但高剂量时会产生毒性作用。我们对一起急性硒中毒事件进行了调查。
病例定义为在2008年1月1日之后购买的由“A公司”生产的膳食补充剂摄入后2周内出现硒中毒症状的人。我们进行了病例查找，向受影响人员发放了初始问卷和90天随访问卷，并在可获得的情况下获取实验室数据。
此次疫情的源头被确定为一种液体膳食补充剂，其含有的硒浓度是标签标注浓度的200倍。在10个州确认的201例病例中，1人住院。估计摄入硒的中位剂量为41749微克/天（推荐膳食摄入量为55微克/天）。常见症状包括腹泻（78%）、疲劳（75%）、脱发（72%）、关节疼痛（70%）、指甲变色或变脆（61%）以及恶心（58%）。持续90天或更长时间的症状包括指甲变色和脱落（52%）、疲劳（35%）以及脱发（29%）。8例患者的初始血清硒平均浓度为751微克/升（参考范围，≤125微克/升）。7例患者的初始尿硒平均浓度为166微克/24小时（参考范围，≤55微克/24小时）。
液体膳食补充剂中硒的毒性浓度导致了此次广泛爆发。如果制造商遵循制药行业使用的标准，这一事件或许可以避免。
