Dietary Supplement Suspected of Causing Selenium Poisoning
Case finding study suggests liquid supplement responsible for 201 cases in 10 states
THURSDAY, Feb. 11 (HealthDay News) -- A liquid dietary supplement that contained 200 times the labeled concentration of selenium caused a widespread outbreak of selenium poisoning affecting 201 people in 10 states, according to a study published in the Feb. 8 issue of the Archives of Internal Medicine.
Jennifer K. MacFarquhar, R.N., of the U.S. Centers for Disease Control and Prevention in Atlanta, and colleagues conducted a case finding study of people who had ingested the supplement purchased after Jan. 1, 2008 and who developed symptoms of selenium poisoning such as diarrhea, fatigue, hair loss and joint pain within two weeks.
The researchers identified 201 consumers (one of whom was hospitalized) in 10 states who ingested a median dose of selenium of 41,749 µg a day, compared to the recommended daily dose of 55 µg. As a result, 78 percent reported diarrhea, 75 percent had fatigue, 72 percent experienced hair loss, and 70 percent had joint pain. Other symptoms that persisted for 90 days or more included fingernail discoloration, reported by 52 percent of cases, and continued fatigue, reported by 35 percent, the investigators found.
"Had the manufacturers been held to standards used in the pharmaceutical industry, this outbreak may have been prevented," the authors write. "Gaps in existing regulations present a significant public health risk, and attention should be directed at correcting them to prevent recurring outbreaks such as this."