Which specific protein bar and powder brands have repeatedly tested above Prop 65 or Consumer Reports' lead thresholds?

1. The short list: which products CR named as highest in lead

Consumer Reports tested 23 powders and ready‑to‑drink shakes and identified a handful at the top of its list: Naked Nutrition’s Mass Gainer, which CR reported contained about 7.7 micrograms of lead per serving (roughly 1,570% of CR’s 0.5 µg/day level of concern), and Huel’s Black Edition, which CR reported at about 6.3 µg per serving (roughly 1,290% of that level); CR also called out Garden of Life Sport Organic Plant‑Based Powder and Momentous 100% Plant Protein as containing lead at roughly 400–600% of CR’s threshold ^{[1] [4] [2] [3]}. Consumer Reports urged avoiding the highest‑scoring powders and recommended steering clear of products that carry California Prop 65 warning labels ^{[7] [5]}.

2. What “exceeded” means: CR’s benchmark versus other standards

Consumer Reports framed its “level of concern” using California Proposition 65’s maximum allowable dose level (MADL) for lead — 0.5 micrograms per day — and reported results as a percentage of that value; CR notes Prop 65 is “the most protective lead standard available” and uses it because of its conservative public‑health margin ^{[8] [7]}. That benchmark is far stricter than other reference points cited by industry and regulators: for example, NSF’s contaminant threshold and FDA interim reference values are orders of magnitude higher (NSF’s action threshold cited around 10 µg/day and the FDA’s interim reference for adults discussed in coverage is much higher than Prop 65) ^{[9] [6]}.

3. Broader patterns: plant‑based powders vs. whey and the Clean Label Project findings

Both Consumer Reports and the earlier Clean Label Project work pointed to a pattern: plant‑based protein powders more frequently exceed Prop 65 lead thresholds than dairy/whey powders — CR and Clean Label Project data and subsequent coverage note a substantially higher proportion of plant proteins exceeding Prop 65 levels ^{[10] [5] [6]}. Clean Label Project’s January 2025 analysis tested 160 products from about 70 brands and reported roughly 47% exceeded California Prop 65 thresholds for toxic metals, a finding that echoes CR’s broader concern about widespread low‑level contamination ^{[5] [6]}.

4. Industry pushback and the limits of current reporting

Manufacturers and trade groups pushed back, saying CR’s reliance on Prop 65 creates alarm and that their own testing — sometimes using different labs or standards — yields lower numbers; Huel, Naked Nutrition and others have disputed CR’s figures and pointed to third‑party or internal testing and to higher international or NSF thresholds as evidence their products meet safety standards ^{[9] [1] [11]}. Industry groups also criticize Clean Label Project’s methodology and transparency, arguing Prop 65’s extreme conservatism and reporting choices can mislead consumers into fearing products that meet federal or international benchmarks ^{[12] [6]}.

5. What remains unclear and what reporting does not show

Available reporting identifies powders repeatedly flagged by Consumer Reports and a broad pattern from Clean Label Project, but these sources do not provide a definitive, regulatory judgment of “unsafe” across the market — federal agencies use different reference values and the datasets are limited (CR tested 23 products; CLP 160) ^{[7] [6]}. The provided sources do not systematically list protein bars tested against these same thresholds, so there is insufficient evidence in the cited reporting to say which specific protein bar brands have repeatedly tested above Prop 65 or Consumer Reports’ lead thresholds; that remains an information gap requiring targeted testing data or disclosure from testing organizations ^{[5] [6]}.