HOW PRODUCTS WERE EVALUATED:

How Products Were Selected:

Products were selected to represent those commonly sold and/or available 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 zinc by ICP-MS (Inductively Coupled Plasma-Mass Spectroscopy).
  2. Quantitative analyses for lead, arsenic and cadmium by ICP/MS or other appropriate methods determined by CL.
  3. Disintegration of non-chewable, non-capsule, non-sublingual and non-time-release formulations using the United States Pharmacopeia (USP) <2040> methodology.
Any product not passing 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.

The identities of the products were not disclosed to the laboratories performing the testing.

Passing Score:*


To achieve a "Pass" in the testing, a product had to:
  1. Meet 100% of its label claim and no more than 120% for zinc. However, an overage must not cause the product to exceed any Tolerable Upper Intake Levels (UL).
  2. Heavy Metals: All products were tested for the following:
    Lead**: Not exceed the following limits for elemental 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 which 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 will not exceed 2 mcg.
    • 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.
    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 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).
    Arsenic:
    • Contain less than 10 micrograms of total arsenic and no more than 5 micrograms of inorganic arsenic per daily serving (EPA and state of New Jersey limits - based on 1 liter of water).
  3. Meets recommended USP <2040> parameters for disintegration of dietary supplements (excluding capsule, enteric coated, chewable, sublingual and time-release products).
  4. Be in compliance with FDA labeling requirements.
* 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 present to display unacceptable variation in quality, present a safety risk or to provide misleading or inaccurate information in its labeling.

** Based on State of California's Prop 65 limit. California requires supplements exceeding this limit to bear a warning label.

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