How Products Were Selected:
Products were represent those commonly sold and/or available nationally in the U.S. and Canada. ConsumerLab.com purchased products on the open market through retail stores, on-line retailers or direct sales companies. Products were not accepted directly from manufacturers.
Selenium products were tested in one or more independent laboratories for the following:
- Quantitative analyses of elemental selenium by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) or other appropriate methods determined by CL.
- Quantitative analyses for lead, cadmium and arsenic by ICP/MS (Inductively Coupled Plasma-Mass Spectroscopy) for products containing whole herbs and/or more than 250 mg of minerals per daily dose.
- Disintegration of non-chewable, non-sublingual, non-capsule and non-time release formulations United States Pharmacopeia (USP) <2040> recommendations entitled "Disintegration and Dissolution of Nutritional Supplements."
Any product not passing testing was sent to another independent laboratory to repeat testing for the criterion on which it did not pass.
Products failing to meet any Passing Score were re-tested at a second independent laboratory using similar methods and instrumentation.
ConsumerLab.com may modify or use other appropriate test methods if necessary to test special product formulations.
Identities of products were not disclosed to laboratories performing the testing.
Passing Score: *
To be "Approved" by Consumerlab.com, a product must meet the following requirements:
- A product must contain at least 100% and no more than 135% of the claimed amount of elemental selenium.
- If applicable to the product, it must meet recommended USP parameters for disintegration of vitamin supplements (excluding capsule, sublingual, chewable and time-release products).
- Heavy Metals: Products containing whole herbs and/or 250 mg minerals per daily dose must not exceed the following limits:
- Products marketed for use by children may not exceed California's Prop 65 limits for lead in dietary supplements of 0.5 mcg per recommended daily serving with an additional allowance of 0.8 mcg if the product contains more than 1,000 mg/day of calcium.
- Products with single serving weights of less than 5 grams that are not marketed for use by children, may not exceed the State of California's Prop 65 limits for lead in dietary supplements of 0.5 mcg per recommended daily serving with an additional allowance of 0.4 if containing 250 to 999 mg/day of any combination of elemental calcium, magnesium and potassium or 0.8 mcg if containing 1,000 mg/day of any combination of these minerals. An additional allowance of 0.5 mcg is provided if containing 250-999 mg/day one whole herb (not extract) or 1.0 mcg if containing 1000 mg/day or more whole herb (not extract). However, total lead allowance will not exceed 2 mcg per recommended daily serving.
- Products with single serving weights of 5 grams or more which are not marketed for children may not exceed 2.5 mcg per serving nor 4.0 mcg per daily serving.
- If marketed for use by children, may not exceed 3.0 micrograms of cadmium per recommended daily serving (based on Canada's limit for a child weighing 75 lbs.). If not marketed for use by children, may not exceed 4.1 micrograms of cadmium per recommended daily serving (based on the State of California's Prop 65 limit).
- Contain less than 10 micrograms of total arsenic and no more than 5 micrograms of inorganic arsenic per daily serving (EPA limit and state of New Jersey limits - based on 1 liter of water).
- Meet all FDA labeling requirements.
A "Pass" was based on meeting the above criteria in either the first or second rounds of testing.
* Passing scores allow for specific margins of technical error associated with each analysis. ConsumerLab.com reserves the right to disqualify a product at any time from passing if it considers such product to display unacceptable variation, present a safety risk or to provide misleading or inaccurate information in its labeling.
** Based on State of California's Prop 65 lead limit. California requires supplements exceeding this limit to bear a warning label regarding lead.