Roz Salt Scalp Scrub vs Custom 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
Function of Beauty
Custom Shampoo
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleFragrance allergens and undisclosed fragrance chemicals
Possible1,4-dioxane contamination in surfactants
PossiblePreservative-induced contact dermatitis
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 Function of Beauty.
- We flag Fragrance allergens and undisclosed fragrance chemicals, 1,4-dioxane contamination in surfactants and Preservative-induced contact dermatitis on the Function of Beauty and not on the Credo Beauty.
- The Credo Beauty is salt crystals, mineral-based scrub where the Function of Beauty is water-based liquid shampoo, proprietary formulation, 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