Roz Salt Scalp Scrub vs No 4 Olaplex Bond Maintenance 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
Olaplex
No 4 Olaplex Bond Maintenance Shampoo
PFAS grade
Overall grade
Verdict
Hazard flags
Material
Confidence
PossibleFragrance allergens and undisclosed components
PossibleEye and mucous membrane irritation
PossibleScalp irritation or allergic 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 Olaplex.
- We flag Fragrance allergens and undisclosed components, Eye and mucous membrane irritation and Scalp irritation or allergic contact dermatitis on the Olaplex and not on the Credo Beauty.
- The Credo Beauty is salt crystals, mineral-based scrub where the Olaplex is aqueous shampoo solution with proprietary bond-building technology, 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