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Kiehl's

Smoothing Oil-Infused Leave-In Concentrate

Last verified: March 10, 2026

  • Cyclopentasiloxane
  • Dimethiconol
  • Parfum / Fragrance
  • Argania Spinosa Kernel Oil
  • Orbignya Oleifera Oil / Orbignya Oleifera Seed Oil
  • Linalool
  • Benzyl Salicylate
  • Hexyl Cinnamal
  • Benzyl Alcohol
  • Coumarin
  • Limonene
  • Eugenol
  • Isoeugenol

Why This Product is Rated STOP

Smoothing Oil-Infused Leave-In Concentrate by Kiehl's has been evaluated by Million Marker and contains ingredients with known health concerns. This product is rated STOP, indicating higher concern.

We recommend avoiding STOP-rated products and seeking safer alternatives from our GO or SLOW categories.

Learn more about how Million Marker scores products →

Frequently Asked Questions

Smoothing Oil-Infused Leave-In Concentrate by Kiehl's - Non-toxic Hair Styling + Treatment product rated STOP by Million Marker, free from BPA, phthalates, and parabens

Where to buy

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