Recent case of selenium toxicity points to need for FDA to toughen regulations for supplements.
MacFarguhar et al have written an excellent article in the Feb. 8, 2010 edition of the Archives of Internal Medicine entitled “Acute Selenium Toxicity Associated with a Dietary Supplement.” They report that in 2008 a chiropractor in Florida noted common symptoms of gastrointestinal illness and hair loss among several of his patients. In response to these symptoms these patients had doubled the dose of a dietary supplement they have purchased at the chiropractic office. Due to excellent surveillance work performed by the local health department and the Food and Drug Administration the dietary supplement was identified as the common exposure among all affected persons.
The product causing the selenium toxicity was a blend of 16 vitamins, 12 elements with labeled concentrations, 58 trace elements, 18 amino acids and 3 essential fatty acids, Coenzyme Q10 and antioxidants, all suspended in an ionic colloidal liquid. While the product labeling indicated that it contained 200ug of selenium per fluid ounce, the testing performed by the FDA determined that the actual concentration of selenium was 40,800 ug per fluid ounce, or more than 200 times the labeled concentration. Furthermore, the chromium concentration was 17 times the labeled concentration.
Of great concern is that there is no proven antidote nor curative treatment for selenosis due to an overdose of selenium. Treatment consists of stopping the exposure and providing supportive care for symptoms.
At present, dietary supplements such as vitamins, minerals and herbal products are not subject to premarket review or approval for safety, efficacy or Good Manufacturing Practices. Under the Federal Food, Drug and Cosmetic Act the manufacturer of a finished dietary supplement is responsible for ensuring the safety and the quality of the final product, which includes all ingredients received from suppliers. That responsibility includes testing of received ingredients, including premixed ingredients and the final product.
Had the manufacturer been held to standards used in the pharmaceutical industry this outbreak may have been prevented.
In total more than 200 individuals developed acute selenium toxicity.