What Is COSHH and Why Does It Matter in a Nail Studio?

COSHH stands for the Control of Substances Hazardous to Health. It's a UK regulation that sounds bureaucratic, but it exists because chemicals used in nail studios and other beauty services pose genuine health risks if not properly managed. This article explains what COSHH is, which chemicals it covers, what the health effects are, and what professional studios do to protect both technicians and clients.

What COSHH Is

The Control of Substances Hazardous to Health Regulations 2002 (COSHH) 1 apply to any employer or self-employed person who uses hazardous chemicals in their work. "Hazardous" means the substance can cause harm to health skin irritation, respiratory sensitisation, allergic reaction, organ damage, or cancer.

COSHH places a legal duty on the person running the business to:

1. Identify the hazardous chemicals used.
2. Assess the risk to health from exposure.
3. Control the exposure (through ventilation, PPE, work practices, or substitution of the chemical).
4. Monitor to ensure controls are working.
5. Train staff and inform them of the risks 12.

In a nail studio, this means understanding what chemicals are in the products, what harm they can cause, whether clients or staff are at risk, and what's being done to reduce that risk.

The Hazardous Chemicals in Nail Studios

MMA: The Restricted and Banned Substance

Methyl methacrylate (MMA) was widely used in nail products until the 2000s because it was cheap and created a very hard finish. The problem: MMA is highly toxic.

MMA causes occupational asthma, contact dermatitis, and sensitisation in both technicians and clients. The European Union banned its use in cosmetic nail products in 2005 3. The UK followed with restrictions via the Cosmetic Products Regulations (now the UK Cosmetic Products Regulations post-Brexit) 4.

Is MMA used in the UK? Technically no it's banned in cosmetic nail products. But unlicensed or informal operators sometimes still use it, or products containing MMA are imported illegally. How can you tell if a studio is using MMA?

• Very hard gel that will not soak off in acetone. EMA and UV-cured gel nails will dissolve or soften in acetone within 15–20 minutes. MMA will not. If a nail technician tells you to file the nails off and that soaking in acetone won't work, this is a red flag 3.
• Very strong, unpleasant chemical smell. MMA has a pungent, almost sickly odour. Professional EMA products have a much gentler smell.
• No product labelling. Legitimate nail product companies label their products clearly, with a safety data sheet (SDS) available. If a studio cannot show you the product label or SDS, be suspicious 5.

At MMM Beauty, we use Glitterbels Builder Gel (an EMA-based UV gel system), which is fully compliant with UK Cosmetic Products Regulations and has clear labelling and safety information 6.

EMA and Methacrylate Monomers

Ethyl methacrylate (EMA) is the legal alternative to MMA in UV gel nail products. EMA is less toxic than MMA, but it is still a sensitiser and respiratory irritant 27.

HEMA (hydroxyethyl methacrylate) and TEGDMA (triethylene glycol dimethacrylate) are also common in gel nails. These methacrylate monomers can cause:

• Allergic contact dermatitis in the hands and fingers of technicians and in clients with sensitivity.
• Occupational asthma from inhalation of monomers during application and removal.
• Respiratory sensitisation with repeated exposure 78.

UK prevalence data shows acrylate allergy has increased significantly in beauty professionals over the past 15 years, now affecting approximately 3–5% of occupationally exposed individuals 89.

Acetone

Acetone is used to soak off gel nails and is a solvent in many nail products. It's volatile, meaning it evaporates readily, producing airborne vapour 2.

• HSE EH40 exposure limits: 500 ppm over 8 hours (time-weighted average), with a short-term exposure limit (STEL) of 1,500 ppm over 15 minutes 10.
• Health effects at high exposure: Headache, dizziness, irritation of eyes, nose, and throat; at very high levels, CNS depression and respiratory irritation 2.
• Why ventilation matters: Acetone vapour is denser than air, so it accumulates at floor level and around the nail desk. Without extraction ventilation, vapour concentrations can easily exceed the HSE exposure limits in a small, poorly ventilated space 10.

At MMM Beauty, nail soaking and removal occurs with extraction ventilation running, and gel nails are soaked in a well-ventilated area to minimise both technician and client exposure to acetone vapour.

Nail Dust from E-Filing

When the technician uses an electric file (e-file) on your nails, it creates a fine dust. This dust contains particles of nail keratin and whatever product is on the nail (gel, acrylic, polish, etc.). Inhaled regularly, nail dust poses a respiratory hazard 211.

• Particle size: Nail dust particles are typically 1–10 microns, meaning they can reach the lungs (particles smaller than 5 microns are most harmful) 11.
• Respiratory hazard classification: Nail dust is classified as a respiratory hazard in occupational health literature 2.
• Effects: Chronic inhalation can contribute to occupational asthma and chronic respiratory symptoms in technicians and, potentially, in clients if e-filing is done without proper ventilation 11.

At MMM Beauty, e-filing during service is always conducted with:

• The extraction ventilation running.
• The technician wearing an appropriate dust mask (FFP2 or equivalent).
• Adequate distance and airflow to prevent the client from inhaling high concentrations of dust.

Health Effects: Occupational and Client Risk

Occupational Asthma from Methacrylates

Nail technicians who are regularly exposed to methacrylate monomers without proper ventilation or PPE have developed occupational asthma at measurable rates 712.

Occupational asthma caused by chemical exposure is the most common work-related lung disease in developed countries 12. In nail technicians, the incidence is linked to inadequate ventilation and long-term inhalation exposure 7.

Symptoms include:

• Cough, wheezing, and shortness of breath during or shortly after work shifts.
• Symptoms that improve on rest days or holidays and worsen on return to work.
• Chest tightness and difficulty breathing.

Once sensitised, the technician's airways remain reactive to methacrylates, and continued exposure can lead to permanent changes in lung function 7.

Contact Dermatitis

Methacrylate monomers, particularly HEMA and TEGDMA, are skin sensitisers 8. Technicians who handle gel products without gloves, or clients with broken skin or existing dermatitis, can develop allergic contact dermatitis on the hands and fingers 89.

The incidence of acrylate sensitisation among UK beauty professionals has increased substantially: studies from 2015–2023 show prevalence rates between 2–5%, compared to less than 1% in the general population 89.

Important for clients: If you have a history of contact dermatitis, atopic dermatitis (eczema), or known allergy to acrylates or methacrylates, inform Meghan before your appointment. A patch test before gel nail application is essential 8.

Client Exposure vs Worker Exposure

Clients are at lower risk than technicians because:

• Exposure is periodic (a few hours per appointment, perhaps monthly), not daily.
• Clients are not inhaling the high concentrations of monomer vapour that accumulate around the nail desk in a poorly ventilated space.

However, clients with sensitivities, pre-existing respiratory conditions, or atopic dermatitis are at risk and should:

• Ensure the studio has good ventilation (extraction fan running visibly during your appointment).
• Request that the technician wears a dust mask during e-filing.
• Disclose any sensitivities to acrylates so the technician can use appropriate PPE and minimise your exposure 27.

The COSHH Assessment and What It Means

A professional nail studio conducts a COSHH assessment for each hazardous chemical used. The assessment documents:

1. What the chemical is and what products contain it (e.g., "HEMA and TEGDMA in Glitterbels Builder Gel").
2. How it's used (e.g., "applied to nails during gel manicure service, removed via acetone soak").
3. Who is exposed (technician, client, both).
4. What the hazards are (e.g., skin sensitiser, respiratory irritant).
5. What controls are in place (e.g., extraction ventilation, PPE, glove use).
6. How the controls are monitored (e.g., visual inspection of ventilation, staff training) 12.

At MMM Beauty, COSHH assessments are documented and available for review. They inform every appointment and guide how services are delivered safely.

SDS and Labelling: What to Look For

All hazardous chemicals must come with a Safety Data Sheet (SDS), a document that lists the hazards, exposure limits, PPE requirements, and emergency procedures. UK Cosmetic Products Regulations also require that cosmetic products are labelled with ingredient information and, for certain substances, warning labels 4.

What a professional studio should have:

• Original product containers with clear labels (not decanted into unmarked bottles).
• SDS for each product readily available (paper or digital).
• Access to the HSE Chemical Safety Summaries or similar resources.

What to ask:

• "Do you have the SDS for your gel products?" A professional answer is yes, and they can show it to you or email it.
• "What ventilation do you use during nail services?" A professional answer describes extraction ventilation at the nail desk.

What to Look For When Choosing Any Nail Studio

Ventilation

Is there an extraction fan or ventilation system running during services? You should hear or feel airflow at the nail desk, or see an extraction hood above the station 10. Poor or no ventilation is a major red flag.

PPE and Work Practices

• Does the technician wear gloves? Are they changed between clients?
• Does the technician wear a dust mask during e-filing?
• Are products in original, labelled containers?

Product Knowledge

A professional technician can tell you:

• The brand and type of gel (e.g., "Glitterbels Builder Gel, EMA-based UV gel").
• What's in it (e.g., "HEMA, TEGDMA, and photoinitiators; it's acetone-soluble").
• Where the SDS is.

FAQ

Q: Is acetone dangerous?

Acetone is low-toxicity at the exposures you'd get from a single appointment in a well-ventilated space. However, chronic exposure to high vapour concentrations (in poorly ventilated salons or for technicians without proper extraction) can cause headaches, dizziness, and respiratory irritation. Proper ventilation keeps exposure within safe limits 10.

Q: I've had gel nails for years with no problems. Should I be concerned?

Individual sensitivity varies. Some people tolerate methacrylates well; others develop sensitisation over time. If you've never had a reaction, the risk is lower, but a patch test before a new product or formulation is still valuable. If you experience redness, itching, or dermatitis on your hands during or after gel services, inform your technician and consider getting formally tested for acrylate allergy 8.

Q: How do I know if a studio is using MMA?

Ask directly: "Are your gel nails EMA-based or MMA-based?" A professional studio uses EMA-based gel and can show you the product label. If you're suspicious (very hard nails that won't soak off, very strong smell, no product labelling), do not use that studio. Report concerns to your local authority Environmental Health department.

Q: Does COSHH apply only to nail technicians, or does it protect clients too?

COSHH is employer/self-employed person responsibility the duty falls on Meghan, not on clients. However, the regulations protect clients indirectly because they require the business to identify and control hazards that might affect anyone present, including clients. A studio that meets COSHH standards is one where clients are also protected 1.