What Is Alcohol Denat. Sd Alcohol 38-C?
Alcohol Denat. Sd Alcohol 38-C is a specially treated form of ethyl alcohol that has been “denatured,” meaning it has additives that make it unfit for drinking. In this case the denaturants are menthol and a small amount of formaldehyde solution, following the rules set out in the United States regulations known as 27 CFR 21. Chemically, the backbone is the same ethanol you might find in a beverage, but once denatured it becomes purely a functional ingredient for industrial and cosmetic use.
Ethyl alcohol has been used for centuries as a cleaning and preserving agent, and it found its way into personal care formulas early in the development of modern cosmetics. Denatured versions like SD Alcohol 38-C allowed companies to harness the useful properties of alcohol without attracting beverage taxes or misuse. Over time formulators fine tuned the choice of denaturants to balance safety, cost, and odor, which led to the menthol and formaldehyde blend used in this grade.
Production starts with fermenting plant sugars—often from corn or sugarcane—to create ethanol. After distillation, precise amounts of menthol and formaldehyde solution are blended in to meet legal standards. The resulting liquid is clear, fast evaporating, and has a characteristic cooling scent thanks to the menthol.
You will typically see Alcohol Denat. Sd Alcohol 38-C in products where quick dry down or a lightweight feel is important. That includes facial toners, setting sprays, makeup removers, hair styling sprays, aftershaves, and some gel or serum textures aimed at oily or combination skin. Its presence helps other ingredients dissolve and stay evenly mixed, while also giving formulas a refreshing, non greasy finish.
Alcohol Denat. Sd Alcohol 38-C’s Cosmetic Benefits/Uses
In skincare and beauty formulas this ingredient serves one primary purpose.
As a solvent it dissolves active compounds, fragrances, and film formers so they can be evenly distributed throughout the product. This improves texture, ensures consistent performance, and can enhance the delivery of beneficial ingredients onto the skin or hair. The quick evaporation of the alcohol also leaves behind a light, fresh feel that many consumers enjoy in products like toners and sprays.
Who Can Use Alcohol Denat. Sd Alcohol 38-C
Products containing Alcohol Denat. Sd Alcohol 38-C usually suit normal, oily or combination skin because its fast-evaporating nature leaves little residue and can help reduce surface oil. People with dry, sensitive or compromised skin may find it too drying or notice stinging because alcohol can strip away natural lipids and weaken the skin barrier. If your complexion is already reactive or prone to redness it may be wise to choose formulas that rely on gentler solvents.
The ingredient is produced from plant fermentation and the added menthol and formaldehyde solution are synthetic or plant derived, so the alcohol itself is considered suitable for vegans and vegetarians. Always check the full product label though, as other components in the finished formula could be animal sourced.
Topically applied SD Alcohol 38-C is not known to pose a specific risk during pregnancy or breastfeeding because systemic absorption is minimal, yet research on its use in these groups is limited. This is not medical advice and anyone who is pregnant or nursing should show the complete ingredient list of any cosmetic they plan to use to their healthcare provider just to be safe.
The ingredient does not make skin more sensitive to sunlight and on its own does not require extra sun protection. It can, however, enhance penetration of other actives so if your formula contains photosensitising ingredients like certain essential oils or acids, daily sunscreen is still important.
Potential Side Effects/Adverse Reactions
Reactions to topical Alcohol Denat. Sd Alcohol 38-C differ from person to person. The points below outline potential side effects that could occur, yet most users will not experience any problems when the ingredient is used at typical cosmetic levels.
- Dryness or a feeling of tight skin
- Transient stinging or burning on application, especially on broken or freshly exfoliated skin
- Irritation or redness in sensitive skin types
- Contact dermatitis in individuals allergic to menthol or formaldehyde
- Exacerbation of conditions like rosacea due to barrier disruption
- Eye irritation if the product accidentally gets into the eyes
If you notice any persistent discomfort, redness or swelling after using a product containing this ingredient stop using it immediately and consult a healthcare professional.
Comedogenic Rating
Rating: 0/5
Alcohol Denat. Sd Alcohol 38-C flashes off the skin almost instantly and leaves no oily film that could block pores. Because it is a lightweight volatile liquid its molecules do not lodge inside follicles, which is why it scores a zero on the comedogenic scale.
That means the ingredient is generally considered safe for those who are prone to acne or breakouts. The only caveat is that over-drying can sometimes trigger rebound oil production in very oily skin, so overall formulation balance still matters.
No other red flags regarding pore clogging have been documented for this grade of denatured alcohol.
Summary
Alcohol Denat. Sd Alcohol 38-C is used mainly as a solvent that dissolves fragrances, actives and film formers then evaporates rapidly to leave a light non-greasy finish. Its quick dry down helps products feel weightless and can improve the delivery of other ingredients onto skin or hair.
Thanks to its affordability and reliable performance it appears in a broad range of toners, sprays, aftershaves and styling products, although some brands avoid it when formulating for very dry or sensitive skin audiences.
Topical use at cosmetic levels is considered low risk for the general population. Irritation is possible for some people, particularly those with sensitive or compromised skin barriers, so it is always smart to patch test any new product containing this ingredient before applying it more widely.