It is a common mistake for Nail Techs to confuse the ingredients HEMA and Di-HEMA, thinking they are the same. Unfortunately, some Educators are also confused and misinformed.

HEMA

  • 2-hydroxyethyl methacrylate or

  • hydroxyethyl methacrylate

Di-HEMA

  • Di-HEMA trimethylhexyl dicarbamate


In reality, both are monomers used to polymerise UV gels. However, the molecular size of HEMA is much smaller and can be more easily absorbed into the skin.

According to the British Association of Dermatologists (BOD) and all other published scientific articles, HEMA is the # 1 allergen product for nail products. In comparison, the European Scientific Committee for Consumer Safety (SCCS) - the scientists who decide which ingredients can be used for cosmetics - published a report in 2018 that stated that there is no scientific evidence that Di-HEMA causes allergies!

Incidentally, hydroxypropyl methacrylate (2-HPMA), which is also called hydroxypropyl methacrylate (HPMA), is the second most common nail product allergen according to the BOD. This is used by some factories and brands as an alternative to HEMA and in HEMA-free acrylic liquid. As a consequence, those who changed to HEMA-free monomer because they already had an allergy to HEMA, often then develop an allergy to HPMA as well.