Roz Salt Scalp Scrub vs Medium Hair Shampoo: 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
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleFragrance allergens or undisclosed fragrance components
ReportedMechanical irritation from crystal size and shape
Ouai
Medium Hair Shampoo
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleFragrance allergens and undisclosed fragrance components
PossiblePreservative-related contact dermatitis
Reported1,4-dioxane (contaminant in surfactants)
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 undisclosed fragrance components, Preservative-related contact dermatitis, 1,4-dioxane (contaminant in surfactants) and Eye and mucous membrane irritation from surfactants on the Ouai and not on the Credo Beauty.
- The Credo Beauty is salt crystals, mineral-based scrub where the Ouai is Aqueous shampoo formulation (surfactants, conditioning agents, water), 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 →
More shampoo: see the full ranking