How Products were Selected:
Products tested 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, and direct sales or multi-level marketing companies. Products were not accepted directly from manufacturers.
Bilberry products were tested for identity using the United States Pharmacopeia (USP) Dietary Supplement Compendium criteria (see below) and total amount of anthocyanosides in an independent laboratory using high performance liquid chromatography (HPLC). The total amount of the following anthocyanosides were calculated as Cyanidin-3-O-glucoside; Delphinidin-3-O-galactoside, delphinidin-3-O-glucoside, cyanidin-3-O-galactoside, delphinidin-3-O-arabinoside, cyanidin-3-O-glucoside, petunidin-3-O-galactoside, cyanidin-3-O-arabinoside, petunidin-3-O-glucoside, peonidin-3-O-galactoside, petunidin-3-O-arabinoside, peonidin-3-O-glucoside, malvidin-3-O-galactoside, peonidin-3-O-arabinoside, malvidin-3-O-glucoside and malvidin-3-O-arabinoside.
Analyses for lead, cadmium and arsenic were performed using an ICP-MS (inductively Coupled Plasma-Mass Spectroscopy).
Disintegration of non-chewable, non-capsule, non-enteric coated and non-time-release formulations was analyzed utilizing United States Pharmacopeia (USP) 36 <2040> recommendations entitled "Disintegration and Dissolution of Nutritional Supplements."
Identities of products were not disclosed to laboratories performing the testing.
Passing the ConsumerLab.com quality criteria included the following:
- Contain 100% and not more than 125% of label claim for total anthocyanosides. For products with no claimed amount a minimum expected amount of 36% total anthocyanosides is expected for extracts and 0.5% for fresh berry.
- Identification: Comply with all USP Dietary Supplement Criteria for identification for bilberry by HPLC.
- The relative retention times of anthocyanoside peaks in the test sample1 chromatogram must correspond to those in the USP reference standard (or equivalent) chromatogram.
- The peaks of delphinidin-3-O-galactoside and 3-O-glucoside represent the greatest peak intensity2 of all the bilberry anthocyanosides in the chromatogram and are of similar intensity.
- Each of the delphinidin-3-O-galactoside and 3-O-glucoside peaks are more intense than cyanidin-3-Oglucoside.
- The peak of cyanidin-3-O-galactoside, delphinidin-3-O-arabinoside and cyanidin-3-O-glucoside is of similar intensity.
- Each of the remaining anthocyanoside peaks is of lower intensity than cyanidin-3-O-glucoside.
The determination of whether peaks are similar in intensity is based on the judgment of ConsumerLab.com.
1Does not apply to blends. Identification criteria were applied to products containing only the extract and/or dried powdered whole bilberry.
2Criteria based on peak intensity (height) not anthocyanoside concentration.
- Heavy metal contamination:
- Not to exceed the State of California's Prop 65 limits for lead contamination in dietary supplements: 0.5 mcg of lead per daily serving with an additional allowance of 0.8 mcg for supplements containing 1,000 mg/day or more of elemental calcium.** For supplements not marketed for use by children, ConsumerLab.com provides an additional allowance of 0.4 mcg if containing 250 to 499 mg/day of elemental calcium, potassium and/or magnesium, 1.0 mcg if containing 500 to 999 mg/day of elemental calcium, potassium and/or magnesium, and an allowance of 0.5 mcg if containing a significant amount of a whole herb (not extract) ingredient or 1.0 mcg for significant amounts of two or more whole herb ingredients. If a maximum recommended daily serving is not defined, a daily serving size will be determined and applied by CL.
- Contain less than 0.3 micrograms of cadmium per gram (World Health Organization/ADI proposed in dried plant materials).
- Contain less than 10 micrograms of arsenic (5 micrograms inorganic) per daily serving (EPA limit - based on 1 liter of water).
**If available for sale in California, a product that exceeds the State of California's Prop 65 limit for lead requires a warning label. However, with or without this warning label, product cannot pass if it exceeds the levels described this paragraph.
- Meet recommended USP 36 <2040> parameters of disintegration for dietary supplements (excluding capsule, enteric coated, chewable and time-release products).
- Comply 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 a safety risk or to provide misleading or inaccurate information in its labeling.
Any product not passing an initial analysis was retested in a second independent laboratory on at least one of the criteria on which it did not initially pass. A "Pass" was based on meeting the above criteria in either the first or second rounds of testing.