Allergic reactions to nail products are not rare. They are increasing. Dermatologists across the U.S. and Europe report a sharp rise in contact dermatitis linked to acrylate chemicals in gel and acrylic nail systems. Two chemicals sit at the center of the problem: HEMA and MMA. If you apply nails for a living, you need to understand what they are, why they cause reactions, how regulations differ on each side of the Atlantic, and what you can do to protect your clients and your license.
What Are HEMA and MMA?
HEMA (2-hydroxyethyl methacrylate) is a monomer found in most gel polishes, builder gels, and gel extensions. It helps gel products adhere to the natural nail plate and contributes to the hard, glossy finish after UV or LED curing. It appears in base coats, color gels, and builder gels from nearly every major brand.
MMA (methyl methacrylate) is a liquid monomer used in acrylic nail systems. It creates a hard, rigid acrylic when mixed with a polymer powder. MMA was the original monomer used in artificial nails in the 1970s and remains in widespread use at discount salons, despite decades of documented harm. The safer alternative is EMA (ethyl methacrylate), which bonds to the nail plate without the same toxicity.
Why They Cause Allergic Reactions
Both HEMA and MMA are sensitizers. Repeated exposure to uncured or partially cured product on the skin triggers the immune system to develop an allergic response. This is called contact sensitization, and it is permanent. Once a client becomes sensitized to HEMA, any future exposure to acrylate-containing products will provoke a reaction.
The reactions range from mild to severe: redness, itching, and swelling around the nail folds; peeling and cracking skin on the fingertips; and in serious cases, onycholysis (separation of the nail plate from the nail bed). Some clients develop reactions not just on their hands but anywhere gel nails touch their skin, including the face and neck.
Sensitization typically happens through one of three routes:
- Skin contact with uncured product. Gel that floods the cuticle or sidewalls and is then cured on the skin is the most common cause.
- Under-cured product. Using an underpowered lamp, curing for too little time, or applying layers that are too thick leaves unreacted monomers in contact with the nail and surrounding skin.
- Cumulative occupational exposure. Nail technicians who handle products without gloves, or who use thin latex gloves that acrylates penetrate, develop sensitization themselves.
MMA poses additional risks beyond allergy. The FDA has documented cases of permanent nail plate damage, loss of sensation in fingertips, and severe respiratory irritation from MMA vapor. MMA acrylics are also dangerously rigid. When caught or jammed, an MMA nail transfers force directly to the natural nail, causing tearing and injury.
EU Regulations vs. U.S. Rules
European Union
The EU restricts HEMA in nail products to professional use only. Consumer (at-home) gel nail kits containing HEMA are banned from sale. Products sold to professionals must carry specific labeling and allergy warnings. As of September 1, 2025, the EU also completely banned TPO (trimethylbenzoyl diphenylphosphine oxide), a common photoinitiator in gel systems, due to reproductive toxicity concerns. The EU operates on the precautionary principle: restrict first, study later.
United States
The U.S. takes the opposite approach. The FDA considers MMA a “poisonous and deleterious substance” when used in nail preparations and removed 100% MMA products from the market in the 1970s through enforcement actions. However, no federal regulation specifically prohibits MMA in nail products. Over 30 states have enacted their own bans, and California’s Department of Toxic Substances Control has adopted MMA in nail products as a priority product for regulatory action. But enforcement is inconsistent, and MMA-containing products remain widely available at beauty supply stores.
HEMA is not restricted at all in the U.S. There is no federal limit on concentration, no labeling requirement for allergy risk, and no distinction between professional and consumer products. Any consumer can buy a HEMA-containing gel kit online with no warnings.
As Dr. Marissa Morrison at the University of Miami Health System explained: “The EU prioritizes preventing harm, and the U.S. is more reactive and addresses risks only after harm is demonstrated.”
HEMA-Free Products That Actually Work
The good news is that HEMA-free formulations have matured significantly. Several professional brands now offer full product lines that eliminate HEMA without sacrificing performance or longevity.
Bio Sculpture has been HEMA-free since its founding. Their entire product range, including Biogel, Builder Gel, EVO, and Colour Gel, is formulated without HEMA and is also TPO-free. All products are allergy-tested and carry a 10-free formulation (no formaldehyde, toluene, DBP, or six other common irritants).
The GelBottle Inc offers a growing HEMA-free line that includes builder gels (BIAB), ProForm polygels, base coats, and top coats. Their HEMA-free products are specifically designed to match the performance of their original line.
Apres Nail reformulated their Extend Gel to be HEMA-free, vegan, and cruelty-free. The non-wipe formula is designed for their Gel-X extension system.
Switching to HEMA-free products does not mean starting over. Most HEMA-free gels cure under the same lamps, apply with the same techniques, and achieve comparable wear times. The transition is a product swap, not a workflow overhaul.
Client Screening and Intake
Every salon should screen for acrylate sensitivity before services. This does not require medical equipment. It requires asking the right questions.
Add these to your intake form or verbal consultation:
- Have you ever had a reaction to gel nails, acrylic nails, or nail glue?
- Have you experienced itching, redness, or peeling around your nails after a salon visit?
- Do you have any known allergies to adhesives, dental composites, or medical acrylates?
- Have you used at-home gel nail kits? (Home kits are a leading cause of sensitization due to improper curing and skin contact.)
If a client answers yes to any of these, use HEMA-free products for their service. Document your product choices in their client record. If they describe an active reaction (swelling, blistering, open skin), do not perform the service and refer them to a dermatologist.
For your own protection as a technician: wear nitrile gloves (not latex, which acrylates can penetrate), change them between clients, and avoid touching uncured product with bare skin.
Liability and Documentation
Product liability claims related to nail allergies are increasing. Protect yourself:
- Keep Safety Data Sheets (SDSs) for every product you use. OSHA requires this, and it is your first line of defense if a client claims a reaction.
- Document product names, batch numbers, and brands used on each client. If a reaction occurs weeks later, you need to identify exactly what was applied.
- Maintain records of client consultations and allergy screening. Written evidence that you asked about sensitivities and chose products accordingly demonstrates due diligence.
- Carry professional liability insurance. Your state board may require it, and even where it is optional, it is not optional in practice. A single allergic reaction claim can cost more than years of premiums.
- Stay current on your state’s ingredient restrictions. MMA bans vary by state. If you are caught using a banned substance, you face license suspension in addition to civil liability.
The Bottom Line
HEMA and MMA are not theoretical risks. They are causing real harm to real clients and real technicians right now. The EU has already acted. The U.S. will likely follow, but you do not need to wait for a federal ban. Switch to HEMA-free products for sensitive clients (or all clients). Screen every new client for acrylate allergies. Document everything. And never use MMA.
Your clients trust you with their health. The products you choose are part of that trust.