California Enacts Musk Reduction Act Restricting Cosmetic Ingredients

SG 172/25

California’s Musk Reduction Act introduces cosmetic ingredient restrictions to protect consumer health and safety.

Passed on October 7, 2025, the Musk Reduction Act expands Section 108980 of the Health and Safety Code, which originally took effect on January 1, 2025.

Effective January 1, 2027, the Act prohibits any person or entity from selling, manufacturing, delivering, holding or offering for sale any cosmetic product that contains specified intentionally added ingredients. These include musk ambrette, musk tibetene, musk moskene, musk xylene and musk ketone, unless the cosmetic falls under specified circumstances.

Restrictions apply to products containing musk ketone (CAS no. 81-14-1) at concentrations exceeding:

• 1.4% in fine fragrances
• 0.56% in eau de toilette
• 0% in oral products
• 0.042% in all other cosmetic products

In addition, the following ingredients will become prohibited under the Musk Reduction Act as of January 1, 2027:

1. Lily aldehyde (CAS no. 80-54-6).
2. Acetaldehyde (CAS no. 75-07-0).
3. Cyclohexylamine (CAS no. 108-91-8).
4. Cyclotetrasiloxane (CAS no. 556-67-2).
5. Phytonadione (CAS no. 84-80-0).
6. Sodium perborate (CAS no. 15120-21-5).
7. Styrene (CAS no. 100-42-5).
8. Trichloroacetic acid (CAS no. 76-03-9).
9. Tricresyl phosphate (CAS no. 1330-78-5).
10. Vinyl acetate (CAS no. 108-05-4).
11. 2-Chloracetamide (CAS no. 79-07-2).
12. Allyl isothiocyanate (CAS no. 57-06-7).
13. Anthraquinone (CAS no. 84-65-1).
14. Malachite green (CAS no. 569-64-2).
15. Oil from the seeds of Laurus nobilis L. (CAS no. 84603-73-6).
16. Pyrogallol (CAS no. 87-66-1).
17. C.I. disperse blue 1 (CAS no. 2475-45-8).
18. Trisodium nitrilotriacetate (CAS no. 5064-31-3).
19. The following boron substances:
    1. Perboric acids:
       1. Sodium salt (CAS no. 11138-47-9).
       2. Sodium salt, monohydrate (CAS no. 12040-72-1).
       3. Sodium perborate monohydrate (CAS no. 10332-33-9).
    2. Boric acid (CAS nos. 10043-35-3 and 11113-50-1).
    3. Borates, tetraborates, octaborates, and boric acid salts and esters, including all of the following:
       1. Disodium octaborate anhydrous (CAS no. 12008-41-2).
       2. Disodium octaborate tetrahydrate (CAS no. 12280-03-4).
       3. 2-Aminoethanol, monoester with boric acid (CAS no. 10377-81-8).
       4. 2-Hydroxypropyl ammonium dihydrogen orthoborate (CAS no. 68003-13-4).
       5. Potassium borate, boric acid potassium salt (CAS no. 12712-38-8).
       6. Trioctyldodecyl borate.
       7. Zinc borate (CAS no. 1332-07-6).
       8. Sodium borate, disodium tetraborate anhydrous; boric acid, sodium salt (CAS no. 1330-43-4).
       9. Tetraboron disodium heptaoxide, hydrate (CAS no. 12267-73-1).
       10. Orthoboric acid, sodium salt (CAS no. 13840-56-7).
       11. Disodium tetraborate decahydrate; borax decahydrate (CAS no. 1303-96-4).
       12. Disodium tetraborate pentahydrate; borax pentahydrate (CAS no. 12179-04-3).
20. C.I. disperse blue 3 (CAS no. 2475-46-9).
21. Basic green 1 (CAS no. 633-03-4).
22. Basic blue 7 (CAS no. 2390-60-5).
23. 3(or5)-((4-(benzylmethylamino)phenyl)azo)-1,2-(or1,4)-dimethyl-1H-1,2,4-triazolium and its salts (CAS nos. 89959-98-8 and 12221-69-1).
24. Basic violet 4 (CAS no. 2390-59-2).
25. Basic blue 3 (CAS no. 33203-82-6).
26. Basic blue 9 (CAS no. 61-73-4).
27. Musk ambrette (CAS no. 83-66-9).
28. Musk tibetene (CAS no. 145-39-1).
29. Musk moskene (CAS no. 116-66-5).
30. Musk xylene (CAS no. 81-15-2).

An exemption applies to cosmetic products that contain unavoidable trace quantities of the listed ingredients. Such trace levels must result from impurities in natural or synthetic ingredients, the manufacturing process, storage conditions or migration from packaging materials. These trace quantities must not cause the cosmetic product to violate this section of the Act.

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