What Is Nonyl Nonoxynol-7 Phosphate?
Nonyl Nonoxynol-7 Phosphate is a synthetic surfactant made by linking nonylphenol to about seven units of ethylene oxide and then adding a phosphate group. The process starts with nonylphenol, which comes from petroleum, reacts it with ethylene oxide to create a water-loving chain, then treats the result with phosphoric acid to form the final phosphate ester. Chemists began using nonylphenol surfactants in household and personal care formulas in the mid-1900s because they break up oil and dirt so well. The phosphate version was later developed to be milder on skin and more stable in a wide range of pH levels, making it suitable for modern skincare. Today you will most often find Nonyl Nonoxynol-7 Phosphate in facial cleansers, liquid hand soaps, body washes, shampoo, micellar waters and some rinse-off masks that aim to remove heavy makeup or sunscreen.
Nonyl Nonoxynol-7 Phosphate’s Cosmetic Benefits/Uses
This ingredient mainly serves one purpose in a formula, but it plays that role very effectively.
As a cleansing agent, Nonyl Nonoxynol-7 Phosphate lowers the surface tension of water so it can mix with oils and grime on the skin or hair. This allows the unwanted buildup to lift away easily when you rinse, giving a fresh clean feel without leaving a tight or stripped sensation.
Who Can Use Nonyl Nonoxynol-7 Phosphate
Most skin types, including normal, oily and combination skin, tolerate this surfactant without trouble because it is designed to cleanse effectively while remaining relatively mild. Dry or very sensitive skin can usually use it too, but may prefer formulas where it is paired with extra soothing or hydrating ingredients, as any surfactant has the potential to feel slightly drying if overused.
The ingredient is synthetic and sourced from petroleum derivatives rather than animals, so it is generally considered suitable for vegans and vegetarians. Those following strict cruelty-free lifestyles should still verify a finished product’s animal testing policy, as that is determined by the brand not the ingredient itself.
Based on current safety data, products containing Nonyl Nonoxynol-7 Phosphate are not specifically restricted for pregnant or breastfeeding women. Systemic absorption through intact skin is extremely low. That said, this is not medical advice. Anyone who is pregnant or nursing should show the full ingredient list of any product they plan to use to a qualified healthcare professional, just to be on the safe side.
The ingredient does not make skin more sensitive to sunlight, so it poses no photosensitivity risk. It also plays well with most other common skincare actives, which is why you will often see it in multi-benefit cleansers and micellar waters.
Potential Side Effects/Adverse Reactions
Responses to topical Nonyl Nonoxynol-7 Phosphate can vary from one person to another. The points below outline potential side effects only. When the ingredient is used at the concentrations typical for rinse-off products, most people experience none of these issues.
- Mild transient stinging or redness in very sensitive skin, especially if left on for longer than directed
- Dry or tight feeling if used in a formula with no added moisturizers or humectants
- Allergic contact dermatitis in individuals already sensitized to nonylphenol derivatives, though this is rare
- Eye irritation and watering if the product accidentally gets into the eyes before rinsing
If any irritation, rash or discomfort occurs, stop using the product and consult a healthcare professional for guidance.
Comedogenic Rating
Rating: 1 / 5 – Because Nonyl Nonoxynol-7 Phosphate is highly water soluble and used almost exclusively in rinse-off cleansers, it is very unlikely to stay behind on the skin and block pores. Its molecular structure is designed to surround oils and wash them away rather than build up on the surface. In practical terms this makes it an extremely low clogging risk.
For this reason it is generally suitable for people prone to acne or breakouts.
One extra point worth noting is that comedogenicity studies on surfactants are limited, so a theoretical chance of pore congestion can never be fully ruled out. Still, decades of cosmetic use have not flagged this ingredient as a common trigger.
Summary
Nonyl Nonoxynol-7 Phosphate is a synthetic surfactant that excels at cleansing by reducing water’s surface tension so oils, sunscreen and makeup lift off the skin with ease. It is valued for being milder than older non-phosphate nonylphenol surfactants while remaining stable across a wide pH range.
The ingredient sees modest popularity in face washes, micellar waters and shampoos but has some competition from newer plant-derived glucosides and amino acid cleaners. Brands still reach for it when they need reliable oil removal in a formula that feels gentle.
Safety data show very low skin penetration and a low risk of irritation when used as directed, yet every skin is different. When trying any new product that contains Nonyl Nonoxynol-7 Phosphate it is wise to perform a small patch test first to make sure your skin agrees with it.