Plumb
B+

Contaminant lab testing

Clean Label Project

Clean Label Project (nonprofit 501(c)(3))

Hands-on tester Free to read Visit Clean Label Project ↗

Clean Label Project produces genuinely independent, lab-backed contaminant data by purchasing products off shelves — but its undisclosed brand certification fees create a structural conflict: the same companies ranked in public studies can pay CLP for a certification seal, and CLP does not publicly explain whether or how that commercial relationship affects product presentation in rankings.

What it's really for Expose undisclosed contaminants in consumer products and give shoppers a safety-based ranking independent of label claims

What our grade covers The grade on this page is about Supplement and food product contaminant scores (protein powder, prenatal vitamins, infant formula, nutrition bars, pet food, and more), not everything the site does.

Medium Scoring Confidence Mostly sourced, but a detail or two still needs a primary source, so the grade could shift slightly.

Follow the money

Clean Label Project's certification process page states that brands enter a contractual agreement to obtain the CLPC seal; the fee structure is not public. The certification program is the organization's disclosed revenue source, meaning the same brands whose products appear in publicly ranked studies can pay CLP for ongoing certification — a structural conflict even if the underlying lab data is independently generated.

Source →
Operating since
2016 (10 years) · source
What it costs you
Free to read The reviews are free to read.
How they make money
Nonprofit funded primarily by a paid brand certification program (CLPC seal); test results are free to the public. Brands pay to use the Clean Label Project certification mark after passing contaminant thresholds.
What they do
Purchases consumer products (protein powders, prenatal vitamins, infant formula, pet food, and other categories) off retail shelves using their own funds, ships them to accredited third-party labs, and publishes contaminant scores — covering heavy metals, pesticide residues, plasticizers, and other toxins that do not appear on product labels. Results are published free to the public as ranked category studies.
What to watch for
The organization also sells a paid certification seal to brands whose products pass their thresholds. The fee structure for certification is not publicly disclosed, and the site does not clearly explain how a brand's certification status affects its placement or prominence in published category study results. Readers cannot independently verify whether paying for certification influences how products are presented alongside non-certified products in the same rankings.
Composite score
3.60 / 5.00 → grade B+

How the grade was reached

Independence · 30% weight 3 / 5

Does the site take money from the very entities it ranks? Pay-for-placement, vendor-funded data, and affiliate commissions all pull this down. The less the ranking can be bought, the higher the score.

Evidence basis · 30% weight 5 / 5

What is the ranking actually built on? Hands-on testing scores highest, then verified first-hand reviews, then opinion or popularity surveys and self-reported figures, then pay-to-rank, which scores lowest.

Method transparency · 20% weight 3 / 5

Is the methodology published, specific, and reproducible? Can a reader see how a given rank was reached, or is it a black box?

Conflict disclosure · 10% weight 2 / 5

Are commercial relationships, sponsorships, and affiliate arrangements disclosed clearly and near the rankings themselves, rather than buried?

Manipulation resistance · 10% weight 4 / 5

How hard is it to game? Controls against fake reviews, solicited reviews, and vendor gaming raise this; an open box anyone can stuff lowers it.

Evidence

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