How Products Were Selected:Products were selected to present 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. Products were not accepted directly from manufacturers.
- Ascorbic acid by High Performance Liquid Chromatography (HPLC).
- Lead, arsenic, cadmium content by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) for products containing whole herbs and/or more than 250 mg of minerals per daily dose.
- Disintegration of non-chewable, non-capsule and non-timed release formulations utilizing United States Pharmacopeia (USP) <2040> methods.
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.
To be "Approved" by Consumerlab.com, a product must meet the following requirements:
- Contain a minimum of 100% and no more than 120% of its labeled amount of ascorbic acid.
- Heavy Metals: Products containing whole herbs and/or more than 250 mg of minerals per daily dose must not exceed the following limits:
- 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, 0.8 mcg if containing 1000 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) ingredient or 1.0 mcg for products containing 1000 mg/day or more of whole herb (not extract). However, total lead allowance will not exceed 2 mcg per 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.
- 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).
- 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).
- If applicable to the product, it must meet recommended USP <2040> parameters of disintegration of dietary supplements (excluding capsule, chewable, sublingual and timed-release products).
- 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 in quality, present a safety risk or to provide misleading or inaccurate information in its labeling.
** Based on State of California's Prop 65 limits. California requires supplements exceeding this limit to bear a warning label regarding lead.