Roz Salt Scalp Scrub vs Three-OUAI Hair Set: which is safer?
Roz Salt Scalp Scrub is our pick: better on PFAS and on the overall hazard picture.
Our pick
Credo Beauty
Roz Salt Scalp Scrub
PFAS grade
Excellent 100/100
Overall grade
Excellent 86/100
Verdict
Buy
Hazard flags
⚑ 2
Material
salt crystals, mineral-based scrub
Confidence
82%
PossibleFragrance allergens or undisclosed fragrance components
ReportedMechanical irritation from crystal size and shape
Ouai
Three-OUAI Hair Set
PFAS grade
Excellent 75/100
Overall grade
Good 57/100
Verdict
Buy
Hazard flags
⚑ 3
Material
Hair care liquids/sprays (shampoo, conditioner, spray)
Confidence
72%
PossibleFragrance allergens and irritants
Possible1,4-dioxane (manufacturing contaminant)
ReportedScalp or skin irritation from surfactant concentration
Where these two actually differ
- We flag Fragrance allergens or undisclosed fragrance components and Mechanical irritation from crystal size and shape on the Credo Beauty and not on the Ouai.
- We flag Fragrance allergens and irritants, 1,4-dioxane (manufacturing contaminant) and Scalp or skin irritation from surfactant concentration on the Ouai and not on the Credo Beauty.
- The Credo Beauty is salt crystals, mineral-based scrub where the Ouai is Hair care liquids/sprays (shampoo, conditioner, spray), which is most of the difference in these two grades.
- The gap is 25 points, wide enough that this is not a close call, and the Credo Beauty is the one to buy.
Both products run through the same public rubric: materials, coatings, brand disclosure, lab findings, and recalls, plus a beyond-PFAS hazard analysis. Grades are model-based estimates, not lab tests. How grades work →
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