What are HEMA, HPMA, TPO and optical brightener?

HEMA is an abbreviation for 2-hydroxyethyl methacrylate.  It’s a very small chemical that can be absorbed into the skin and bloodstream. In a study of 4,931 people during 2017, HEMA was the most common (meth)acrylate chemical to cause allergic sensitization. This result raised the concern of the British Association of Dermatologists and they published a paper in 2018 warning about the artificial nail products allergy epidemic.

HPMA is an abbreviation for 2-hydroxypropyl methacrylate. It’s the next most common (meth)acrylate chemical to cause allergic reactions in the same study.

TPO is an abbreviation for trimethylbenzoyl diphenylphosphine oxide. It’s considered a moderate skin sensitizer, according to the Scientific Committee on Consumer Safety,one of the independent scientific committees of the European Commission.

Optical brightener is often used to enhance the appearance of the polish colour, and it is suspected to cause allergic reactions when in contact with skin.

What problems can HEMA, HPMA, TPO and optical brightener substances cause in the body?


In 2018, the British Association of Dermatologists issued a warning that (meth)acrylate chemicals such as HEMA and HPMA in acrylic nails, gel nails and gel polish nails are causing a contact allergy epidemic. In a study of 4,931 people in the UK and Ireland, 1.5% of these people were tested positive for allergy to HEMA and 1% were tested positive to HPMA. The study also found that this allergy is predominantly found in women, who made up 93% of those affected.


Allergic reactions to these chemicals may involve loosening of the nails or a severe red, itchy rash, not just on the fingertips, but potentially anywhere on the body that has come into contact with the nails, including the eyelids, face, neck and genital region. Very rarely, symptoms such as breathing problems can occur.


Considering that inappropriate application may cause increased risk of allergic reactions, the European Commission requires that warnings reading “For professional use only” and “Can cause an allergic reaction” appear on the packaging of nail products containing HEMA.


According to a paper published by the Scientific Committee on Consumer Safety in 2014, TPO is safe when used as a nail modelling product at a concentration of at maximum 5.0%. However, the committee holds an opinion that TPO is considered a moderate skin sensitizer. Apparently the safety of TPO is conditional, using TPO-free products will protect you from the potential risks caused by TPO.  

Optical Brightener

Optical brighteners can potentially cause skin irritations. More research is needed to fully understand the long-term effects of exposure to these chemicals. Needless to say, using products without optical brighteners will keep you away from the potential risks.  

Based on these facts, it’s clear that HEMA free, HPMA free, TPO free and optical brightener free gel nail products are much healthier choices compared to traditional products. However, please be aware that gel polish may contain other allergens that can cause allergic reactions. Due to individual differences, different people might be allergic to different substances at different levels. Therefore, it is recommended that you undergo a patch test with your dermatologist to identify your specific allergens.

1. Prep

Trim and file the nails to the desired length and shape. Clean the nails with alcohol pad or nail polish remover. It’s important to ensure your nails are completely clean and oil-free!

2. Apply Base Coat

Apply a thin base coat, and cure under UV lamp for 1 minute, LED light for 30 seconds. Apply to the middle of the nail first and then to both side.

3. Apply Color Coat

Apply a thin color coat and insert hand into LED light for 30-60 seconds or into UV lamp for 2 minutes. Apply a second color coat and insert hand into LED light for 30-60 seconds or into UV lamp for 2 minutes. Apply a third color coat if necessary.

4. Apply Top Coat

Apply a thin top coat and insert hand into LED light for 30-60 seconds or into UV lamp for 2 minutes. Wipe off sticky layer with nail cleanser or sterile alcohol wipes. Complete your manicure with a shiny finish.

5. Removal

File the surface of the nails using a coarse nail file. This helps break through the top coat to allow the remover to penetrate the layers of polish below. Soak a cotton ball with remover and place it on your fingernails, or use ready-to-use removal wraps. Wrap it tightly around your nails with a foil and leave for around 15 minutes, then use an orange stick or cuticle pusher to push it off. Use your buffing block to smooth the surface of each nail and remove any remaining little bits of polish. Wash and moisturize your hands and nails.

Frequently asked question

Use this text to answer questions in as much detail as possible for your customers.


1. Before you open the bottle, please shake the bottle to let the gel keep uniformity.

2. Gently buff off the surface of your nails, and seal the free edge (paint each layer on the edge of your nail), these will help your manicure last longer.

3. When you apply the gel must be thin. Thinner - stronger.

4. Use the same brand gel for the best result, can be use with other brands but not recommended.

5. It is normal for gel polish to remain sticky until you wipe it off with cleaner. You can use the cleanser/alcohol after curing each coat and then it won't be sticky and will give you a smoother surface.

6. If the polish doesn’t push off easily, continue soaking until it does. You should not have to chisel the polish off!

7. Keep tight after use.

Soak-Off Gel Polish & General FAQ’s

A. Does gel polish damage or weaken your nails?

If you properly apply and remove, gel polish should not weaken your nails. It provides extra strength and prevents your nails from ripping and breaking, allowing them to grow longer and stronger. 

B. Why is my gel polish lifting/peeling?

Premature lifting or peeling is often caused by poor nail preparation, it’s one of the biggest reasons why gel polish chips or peels. Some nail polish lovers may believe that it’s all about the polish, when in fact preparation plays just as big a part in how long a manicure lasts. Before applying gel polish ensure your nails are completely dry, clean and oil-free!

Other possible causes are either it did not fully cure – not keeping your fingers under the lamp long enough or they have a weak UV / LED lamp so it needs to cure longer. Or if there’s gel on the skin or cuticle, and isn’t cleaned off prior to curing, the gel will lift at that point. Too-thick coats can also cause peeling.

The brand of base coat could also be the culprit. Do some experimentation to find the brand that works best for you as they don’t all wear the same
on everyone.


C. How do you work with gel polishes that are thick?

Some of the highly pigmented / glitter gel polishes are thicker, especially in cold weather, with these polishes you need to apply very thin coats. Try warming your polish before using it by placing the bottle in warm water before using it. You can also add a few drops of gel polish thinner to make the consistency a little thinner and easier to apply. The key is practice, practice makes everything perfect, once you get used to the consistency, it’s not different to get an even coat and will come out well.

D. Can I mix and match gel polish brands?

Yes, you can use a different brand base and top coat with another brand of color but not recommended. Use the same brand gel for the best result.

E. Will gel polish work without curing under a UV or LED light?

No, it won’t. A UV or LED light is required. Without it the gel polish will never dry.