How Products Were Selected:
Selected products 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 or direct sales companies. Products were not accepted directly from manufacturers.Testing Methods:
- Analyses for zinc by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS).
- Quantitative analyses for lead, arsenic, cadmium and mercury by ICP-MS or other appropriate methods determined by CL.
- Disintegration of tablets (excluding chewable, sublingual and time-release formulations) using the United States Pharmacopeia (USP) <2040> recommendations entitled "Disintegration and Dissolution of Nutritional Supplements."
- Disintegration time of enteric coated, time-release, and sustained release tablet, caplet and softgel formulations utilizing USP <2040> methodology for delayed-release (enteric-coated) tablets."
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 be "Approved" by ConsumerLab.com a product must meet the following requirements:- Contain 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).
- Heavy Metals: All products must not exceed the following limits:
Lead:- Products marketed for use by children under 12 years of age 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 under 12 years of age, may not exceed the State of California's Prop 65 limits for lead in dietary supplements of 0.5 mcg per recommended daily serving (above which a warning regarding reproductive harm, birth defects, or cancer risks is required in California) 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 per daily serving.
- Products with single serving weights of 5 grams or more that are not marketed for children under 12 years of age may not exceed 2.5 mcg per serving nor 4.0 mcg per daily serving.
- Contain less than 10 micrograms of total arsenic per daily serving (based on Canada’s limit per daily serving of a natural health product, and U.S. EPA and state of New Jersey limit in 1 liter of water). Products found to exceed this amount were tested for inorganic arsenic and must not contain more than 2.1 micrograms of inorganic arsenic per daily serving (Canada's additional limit in natural health products).
- If marketed for use by children under 12 years of age, 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 under 12 years of age, may not exceed 4.1 micrograms of cadmium per recommended daily serving (above which California's Prop 65 law requires a "reproductive harm" warning due to developmental toxicity and male reproductive harm.
- May not exceed 2 micrograms of inorganic mercury per daily serving (based on EPA limit for mercury in 1 liter of water).
- If applicable to the product, meet recommended USP <2040> parameters of disintegration of dietary supplement tablets (excluding chewable, sublingual and time-release products).
- Enteric coated, time-release, and sustained release tablet, caplet and softgel formulations must meet recommended USP <2040> parameters for delayed-release (enteric-coated) tablets, caplets and softgels by visual inspection.
- 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 display unacceptable variation, present a safety risk, or to provide misleading or inaccurate information in its labeling.