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About ConsumerLab.com

HOW PRODUCTS WERE EVALUATED:

How Products Were Selected:

Products tested represent those commonly sold and/or available nationally in the U.S. ConsumerLab.com purchased products on the open market through retail stores, on-line retailers, and direct sales companies. Products were not accepted directly from manufacturers.

Testing Methods:

  1. Analyses for potassium using inductively coupled plasma — mass spectroscopy (ICP- MS) or atomic absorption spectroscopy (AA).
  2. Analyses for lead, arsenic, and cadmium using an Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS).
  3. Disintegration of tablets (excluding chewable, sublingual and time-release formulations) using United States Pharmacopeia (USP) <2040> methodology.
Any product that did not initially Pass (below) a test was sent to another independent laboratory to repeat testing for the criterion on which it did not pass.

ConsumerLab.com may modify or use other appropriate test methods if necessary, to test special product formulations.

Identities of the products were not disclosed to laboratories performing testing.

Passing Score:*

To "Pass", a product had to meet the following requirements:
  1. Contain a minimum of 100% and no more than 120% of its labeled amount of elemental potassium.
  2. Heavy Metal
    Lead**:
    • Products 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 0.8 mcg if the product contains more than 1,000 mg/day of calcium.
    • Products with a 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 mcg if containing 250-999 mg/day of any combination of elemental calcium, magnesium and potassium or 0.8 mcg if containing more than 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 of whole herb (not extract) or 1.0 mcg if containing 1000 mg/day or more of whole herb (not extract). However, total lead allowance must not exceed 2 mcg.
    • Products with single serving weights of 5 grams or more that are not marketed for children may not exceed 2.5 mcg per serving nor 4.0 mcg per daily serving.
    Cadmium**:
    • 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 75lbs). 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).
    Arsenic:
    • Contain less than 10 micrograms of total arsenic and no more than 5 micrograms of inorganic arsenic per daily serving (EPA limit - based on 1 liter of water).
  3. Meet recommended USP <2040> parameters of disintegration for dietary supplements (excluding capsule, chewable, sublingual and time-release products).
  4. Be in compliance with 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 its testing if it considers such product to display unacceptable variation represent a safety risk or to provide misleading or inaccurate information in its labeling.
** The State of California's Prop 65 lead limit. California requires supplements exceeding this limit to bear a warning label.

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