What Is Ammonium Phenolsulfonate?
Ammonium phenolsulfonate, also known as ammonium hydroxybenzenesulphonate, is a salt produced when phenol is treated with sulfuric acid and then neutralized with ammonia. The result is a water-soluble powder that carries a mild antiseptic scent. First explored in the early 20th century for its cleansing abilities, it found a place in personal care labs once formulators noticed that it could curb unwanted bacteria without irritating skin. Today large-scale production starts with sustainably sourced phenol, often derived from petroleum by-products or plant biomass. The phenol undergoes sulfonation, is purified to remove excess acid, then combined with pharmaceutical-grade ammonium hydroxide to form a stable crystalline compound. Because it dissolves easily in water and keeps its activity over a wide pH range, it shows up in a variety of formulas. You will most often find it in deodorant sprays, roll-ons, foot creams, purifying face masks, clarifying shampoos and occasional blemish spot treatments where a gentle antimicrobial boost is needed.
Ammonium Phenolsulfonate’s Cosmetic Benefits/Uses
In modern cosmetics this ingredient plays more than one helpful role
- Antimicrobial: It hinders the growth of odor-causing bacteria on skin and scalp which helps products stay fresher longer and keeps users feeling clean
- Deodorant: By reducing the bacteria that break down sweat it lessens unpleasant body odor making it a reliable active in underarm and foot care formulas
Who Can Use Ammonium Phenolsulfonate
This ingredient is generally suitable for all skin types including oily, combination, normal and even sensitive skin because it delivers antimicrobial benefits without a strong stripping or drying effect. Extremely dry or compromised skin may feel a slight tightness if the surrounding formula contains a high percentage of alcohol so choosing a well balanced product matters.
Ammonium phenolsulfonate is a synthetic compound created from phenol and ammonia, neither of which comes from animals, so products featuring it are typically vegan and vegetarian friendly. Always check the full ingredient list though because other components in the same formula might not meet cruelty-free or plant-based standards.
Current safety data does not flag any special risks for women who are pregnant or breastfeeding when the ingredient is used topically at the low levels common in cosmetics. This information is not medical advice and anyone who is expecting or nursing should run products past a qualified healthcare professional just to be safe.
The compound is not known to make skin more sensitive to sunlight so routine use should not heighten the risk of sunburn. It also plays well with most other cosmetic actives and preservatives which makes it easy to slot into multi-step routines without concern for destabilizing reactions.
Potential Side Effects/Adverse Reactions
Side effects and reactions to topical ammonium phenolsulfonate can vary from person to person. The following list covers potential issues yet they are uncommon when the ingredient is formulated and used correctly
- Mild stinging or tingling on very sensitive or freshly shaved skin
- Temporary dryness if paired with high alcohol content or frequent application
- Rare cases of contact irritation presenting as redness or itching
- Allergic response in individuals already sensitized to phenolic compounds
If any discomfort, rash or swelling develops stop using the product and seek advice from a healthcare professional.
Comedogenic Rating
Rating: 0 (non-comedogenic)
Ammonium phenolsulfonate is a small, water-soluble salt that rinses away easily and does not leave an oily or waxy film on skin. Because it does not trap sebum or debris inside pores it earns the lowest score on the comedogenic scale. The molecule also has a mild antimicrobial effect that can actually help keep pore-clogging bacteria in check.
Suitable for acne-prone skin: Yes, its non-occlusive nature makes it a safe choice for those who struggle with breakouts.
Formulas that combine the ingredient with heavy oils, butters or silicones could still feel greasy so the overall product base determines the final pore-clogging potential.
Summary
Ammonium phenolsulfonate acts mainly as an antimicrobial and deodorant agent. It disrupts the cell walls of certain bacteria which slows their growth and in turn reduces unpleasant odors on skin and scalp. Because it dissolves readily in water and stays active across a broad pH range formulators can drop it into sprays, gels or creams without complicated processing.
The compound is not a household name yet it has a steady presence in specialty deodorants, foot treatments and clarifying cleansers where a gentle but effective germ-control boost is needed. Its low cost and easy handling may encourage wider use as consumers look for milder alternatives to traditional preservatives.
Current safety reviews find it non-sensitizing for most users when used at the low percentages typical in cosmetics. Still everyone’s skin is unique so it is smart to perform a quick patch test before fully adopting any new product that lists ammonium phenolsulfonate on the label.