Acute Selenium Toxicity Associated With a Dietary Supplement

Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Archives of internal medicine (Impact Factor: 17.33). 02/2010; 170(3):256-61. DOI: 10.1001/archinternmed.2009.495
Source: PubMed


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.

Full-text preview

Available from:
  • Source
    • "Livestock health problems have also arisen due to high molybdenum contents in the Irish black shales (Alloway, 2012). Selenium availability is important to plants and animals, but in excess can become toxic, which in the case of human consumption is above 400 mg/day (MacFarquhar et al., 2010), with possible consequences including neurotoxicity, cancer and diabetes (Vinceti et al., 2014; Sun et al., 2014). Care is therefore often taken to avoid the delivery of elevated concentrations of selenium to the environment, for example through the processing of fossil fuels, including coal storage (Lussier et al., 2003), coal burning (Zeng et al., 2001), and oil refining (Lawson and Macy, 1995). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The Carboniferous Bowland Shale in England, and its correlatives in Ireland, contain anomalously high concentrations of trace elements, including selenium (Se), molybdenum (Mo) and arsenic (As). High levels of these elements reflect high sulphur contents as these elements occur as trace constituents of pyrite. Anomalous Se in particular may have a volcanic provenance, from contemporary volcanic activity and/or drainage from Ordovician volcanogenic sulphide deposits. Following concern over the release of Se and As into groundwater during shale gas extraction in the US, the potential fate of Se and As during any future shale gas extraction from the Bowland Shale merits attention. It is at least an environmental issue that must be managed, but at best it could be an opportunity for extraction of Se in an environmentally sensitive manner.
    Full-text · Article · Jan 2016 · Applied Geochemistry
  • Source
    • "Selenium has been claimed to reduce the occurrence of a large number of cancers. Favorable effects of selenium intake on AIDS signs, fertility, skin disorders and asthma have also been reported [1] [2] [3]. In humans, selenium deficiency can cause endemic cardiomyopathy known as Keshan disease, which affects children and women of child-bearing age, in particular. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The aims of this study were the screening of main effects and optimization of selenium determination in plasma samples with experimental design methodology.
    Preview · Article · Jun 2014
  • Source
    • "Another high-dose selenium case consisting of the use of a liquid dietary supplement containing 200 times the labeled concentration of selenium was reported in the United States [44]. Of the 201 cases identified in 10 states, 1 person was hospitalized. "
    [Show abstract] [Hide abstract]
    ABSTRACT: To establish guidelines for the selenium supplementation in radiotherapy we assessed the benefits and risks of selenium supplementation in radiotherapy. Clinical studies on the use of selenium in radiotherapy were searched in the PubMed electronic database in January 2013. Sixteen clinical studies were identified among the 167 articles selected in the initial search. Ten articles were observational studies, and the other 6 articles reported studies on the effects of selenium supplementation in patients with cancer who underwent radiotherapy. The studies were conducted worldwide including European, American and Asian countries between 1987 and 2012. Plasma, serum or whole blood selenium levels were common parameters used to assess the effects of radiotherapy and the selenium supplementation status. Selenium supplementation improved the general conditions of the patients, improved their quality of life and reduced the side effects of radiotherapy. At the dose of selenium used in these studies (200-500 mug/day), selenium supplementation did not reduce the effectiveness of radiotherapy, and no toxicities were reported. Selenium supplementation may offer specific benefits for several types of cancer patients who undergo radiotherapy. Because high-dose selenium and long-term supplementation may be unsafe due to selenium toxicity, more evidence-based information and additional research are needed to ensure the therapeutic benefits of selenium supplementation.
    Full-text · Article · May 2014 · Radiation Oncology
Show more