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How Products Were Selected:

Products were selected to represent those popular among readers of and commonly available nationally in the U.S. and Canada. 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:

Greens and Whole Foods products were tested in one or more independent laboratories for the following:
  1. Heavy metals: lead, cadmium, arsenic and mercury by Inductively Coupled Plasma/Mass Spectroscopy (ICP/MS).
  2. Chlorinated pesticides (Not tested in products containing only chlorella and spirulina): Specific chlorinated pesticides listed below in Appendix A from the United States Pharmacopeia (USP) <561> and using a modified FDA-PAM method by High Resolution Gas Chromatography (HRGC) with an electron capture detector (ECD) and HRGC with mass spectroscopy/mass spectroscopy (MS/MS) detection.
  3. Microbial contaminants (Not tested in products containing only chlorella and spirulina): Analysis of microbial contaminants was done using the FDA's Bacteriological Analytical Manual (BAM) and AOAC methodologies with application to USP <2023> guidelines for Escherichia coli, Salmonella, Listeria, yeast and mold in dried or powdered botanicals.
  4. Disintegration of tablets (excluding chewable, sublingual and time-release formulations) was performed using United States Pharmacopeia (USP) <2040> methodology for the disintegration of Dietary Supplements".
Testing was performed by one or more independent laboratories. Any product that did not initially pass testing (as defined below) testing was sent to another independent laboratory to repeat testing for the criteria on which it did not pass. 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. Heavy metals: Products 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 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 (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) ingredient, or 1.0 mcg if containing 1000 mg/day or more 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 or nor 4.0 mcg per daily serving.
    • 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 (above which California's Prop 65 law requires a "reproductive harm" warning due to developmental toxicity and male reproductive harm).
    • Contain less than 10 micrograms of total arsenic per daily serving (based on EPA limit 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 limit in natural health products).
    • May not exceed 2 micrograms of mercury per daily serving (based on EPA limit for mercury in 1 liter of water).
  2. Pesticides: The concentration of any detectable chlorinated pesticide residue(s) must be less than the individual limit(s) listed in Appendix A (below) calculated on a wt./wt. basis (USP <561>).
  3. Microbial contaminants: Products must test negative for E. coli, Salmonella and Listeria. Total combined yeast and mold NMT 1,000 cfu/g USP <2023>.
  4. Gluten: Products labeled "Gluten-free" must contain less than 20 ppm of gluten per serving (FDA); products with large serving sizes (>5 grams or 5 mL) must contain less than 5 ppm of gluten per serving ( applies this stricter requirement on products with larger servings).
  5. Disintegration: If applicable to the product, must meet USP <2040> recommendations for disintegration of dietary supplements (excluding chewable, sublingual and timed-release products).
  6. 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. reserves the right to disqualify a product at any time from passing its testing if it considers such product to present a display unacceptable variation in quality, present a safety risk, or provide misleading or inaccurate information in its labeling.

Appendix A: Pesticides

USP <561>
Substance Limit (mg/kg, ppm)
Acephate 0.1
Alachlor 0.05
Aldrin and Dieldrin (sum of) 0.05
Azinphos-ethyl 0.1
Azinphos-methyl 1.0
Bromide, inorganic (as bromide ion) 50
Bromophos-ethyl 0.05
Bromophos-methyl 0.05
Bromopropylate 3.0
Chlordane (sum of cis- and trans- isomers and oxychlordane) 0.05
Chlorfenvinphos 0.5
Chlorpyrifos-ethyl 0.2
Chlorpyrifos-methyl 0.1
Chlorthal-dimethyl 0.01
Cyfluthrin (sum of) 0.1
?-Cyhalothrin 1.0
Cypermethrin and isomers (sum of) 1.0
DDT (sum of o,p'-DDE, p,p'-DDE, o,p'-DDT p,p'-DDT, o,p'-TDE and p,p'-TDE) 1.0
Deltamethrin 0.5
Diazinon 0.5
Dichlofluanid 0.1
Dichlorvos 1.0
Dicofol 0.5
Dimethoate and omethoate (sum of) 0.1
Dithiocarbamates (as CS2) 2.0
Endosulfan (sum of endosulfan isomers and endosulfan sulfate) 3.0
Endrin 0.05
Ethion 2.0
Etrimphos 0.05
Fenchlorophos (sum of fenchlorophos and fenchlorophos-oxon) 0.1
Fenithrothion 0.5
Fenpropathrin 0.03
Fensulfothion (sum of fensulfothion, fensulfothion-oxon, fensulfothion-oxonsulfon and fensulfothion-sulfon) 0.05
Fenthion (sum of fenthion, fenthion-oxon, fenthion-oxon-sulfon, fenthion-oxon-sulfoxid, fenthion-sulfon and fenthion-sulfoxid 0.05
Fenvalerate 1.5
Flucytrinate 0.05
t-Fluvalinate 0.05
Fonofos 0.05
Heptachlor (sum of heptachlor and cis-heptachlorepoxide and trans-heptachlorepoxide) 0.05
Hexachlorobenzene 0.1
Hexachlorocyclohexane (sum of isomers a-, ß-, d-, and e-) 0.3
Lindane (?-hexachlorocyclohexane) 0.6
Malathion and malaoxon (sum of) 1.0
Mecarbam 0.05
Methacriphos 0.05
Methamidophos 0.05
Methidathion 0.2
Methoxychlor 0.05
Mirex 0.01
Monocrotophos 0.1
Parathion-ethyl and Paraoxon-ethyl (sum of) 0.5
Parathion-methyl and Paraoxon-methyl (sum of) 0.2
Pendimethalin 0.1
Pentachloranisol 0.01
Permethrin and isomers (sum of) 1.0
Phosalone 0.1
Phosmet 0.05
Piperonyl butoxide 3.0
Pirimiphos-ethyl 0.05
Pirimiphos-methyl (sum of Pirimiphos-methyl and N-desethyl-pirimiphos-methyl 4.0
Procymidone 0.1
Profenophos 0.1
Prothiophos 0.05
Pyrethrum (sum of cinerin l, cinerein II, jasmolin II, pyrethrin I and pyrethrin II 3.0
Quinalphos 0.05
Quintozene (sum of quintozene, pentachloroanaline and methylpentachlorophenyl sulfide) 1.0
S-421 0.02
Tecnazene 0.05
Tetradifon 0.3
Vinclozolin 0.4

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