What Is Vape Juice Made Of?

Complete UK Ingredients Guide 2025

Vape juice contains four ingredients: Propylene Glycol (PG), Vegetable Glycerin (VG), nicotine, and flavourings. That's it. In the UK, these ingredients are strictly regulated by TPD laws and tested by the MHRA before any e-liquid can be sold.

If you're switching from smoking to vaping, you need facts, not scaremongering. Here's exactly what's in UK e-liquid, why it's there, and what the actual evidence says about safety - not American propaganda about popcorn lung that doesn't apply to UK products.

The Four Ingredients of UK Vape Juice - What They Actually Do

Propylene Glycol (PG) - The Throat Hit Ingredient

PG is a thin, colourless liquid that carries flavour and creates the throat hit smokers recognise. It's the same ingredient used in asthma inhalers, stage fog machines, and thousands of food products.

What PG does in vape juice:

• Creates throat sensation (50% of most e-liquids)
• Carries flavour molecules effectively
• Produces less visible vapour
• Thinner consistency for pod systems
• Pharmaceutical grade in UK products

The UK MHRA classifies PG as safe for use in e-cigarettes when it meets pharmaceutical standards. It's been used in nebulisers and inhalers for decades.

Vegetable Glycerin (VG) - The Cloud Maker

VG is a thick, slightly sweet liquid derived from vegetable oils. It produces the visible vapour clouds and provides a smoother inhale than PG alone.

What VG does in vape juice:

• Creates visible vapour clouds
• Smooths the throat hit
• Adds slight sweetness
• Thicker consistency (needs more power)
• Makes up 30-80% of e-liquid

VG showed only limited biological effects with no signs of toxicity in 90-day inhalation studies. It's used in cough medicines, toothpaste, and hundreds of foods.

Nicotine - The Optional Addictive Part

Nicotine in UK e-liquid is pharmaceutical grade, the same quality used in patches and gum. UK law limits it to 20mg/ml maximum - that's the TPD regulation that's been in place since 2016.

• Nicotine facts in UK vape juice:
• Optional (0mg available)
• Maximum 20mg/ml by law
• Extracted from tobacco or synthetic
• Same as NHS nicotine products
• Not carcinogenic itself

The nicotine isn't what causes cancer in cigarettes - it's the 7,000 chemicals from burning tobacco. That's why the NHS offers nicotine replacement therapy.

Flavourings - Food Grade Only

All flavourings in UK e-liquid must be food-grade and pass emissions testing. The MHRA requires full ingredient disclosure and testing before approval.

UK flavouring regulations:

• Food-grade quality required
• Emissions tested when heated
• Full ingredient listing to MHRA
• 6-month approval process
• Banned: diacetyl, acetyl propionyl, caffeine, taurine

UK Testing and Regulations - What Actually Protects You

TPD/TRPR Requirements

The Tobacco and Related Products Regulations control everything about UK vape juice:

 

MHRA Testing Process

Before any e-liquid hits UK shelves:

1. Full ingredient submission to MHRA

2. Emissions testing data required

3. Toxicological reports submitted

4. 6-month review period

5. Published on MHRA database

This doesn't happen in America. Their FDA only started properly regulating in 2016.

What's NOT in UK Vape Juice - The Banned List

Completely Banned Ingredients

UK law specifically prohibits:

• Diacetyl - The "popcorn lung" chemical (banned since 2016)

• Acetyl Propionyl - Similar respiratory risks

• Caffeine - Stimulants not allowed

• Taurine - Energy drink ingredients banned

• Colouring agents - No artificial colours

• Vitamin E Acetate - Linked to US lung injuries

What You're NOT Inhaling vs Cigarettes

Cigarettes contain 7,000+ chemicals including:

• Tar (70+ carcinogens)

• Carbon monoxide

• Ammonia

• Arsenic

• Formaldehyde

• Hydrogen cyanide

• Lead

• Benzene

None of these are in e-liquid. That's why Public Health England maintains vaping is "at least 95% less harmful" despite the controversy.

The Safety Evidence - What Science Actually Says

The 95% Safer Claim Explained

Yes, the PHE's 95% figure has critics. But even critics acknowledge:

• E-cigarettes contain far fewer toxicants than cigarettes

• No combustion means no tar or carbon monoxide

• Royal College of Physicians agrees with the harm reduction approach

PG/VG Inhalation Research

Recent studies show mixed but mostly reassuring results:

• 2017 rat study: "Limited biological effects with no toxicity" from PG/VG

• 2019 human trial: Slight inflammation in some users, within normal range

• 2024 review: Some respiratory irritation possible, far less than smoking

The key: These ingredients aren't "safe" - they're "safer than smoking" Which kills 78,000 UK people yearly.

VG/PG Ratios - What They Mean for You

Most UK vapers use 50/50 for pods or 70/30 for sub-ohm. That's the sweet spot.

How E-Liquid Is Made - The UK Process

UK manufacturers must follow pharmaceutical standards:

1. Raw materials tested - PG/VG must be pharmaceutical grade

2. Clean room mixing - ISO 7 clean rooms required

3. Batch testing - Every batch is tested for purity

4. Emissions testing - Heated vapour analysed for compounds

5. MHRA submission - All data submitted 6 months before sale

6. Ongoing monitoring - Adverse events tracked

This is why UK e-liquid costs more than dodgy imports. You're paying for safety testing.

Buying Guide - What to Look For

Quality Indicators

✓ TPD compliant logo 

✓ MHRA registration number 

✓ Full ingredient list 

✓ UK manufacturer address 

✓ Batch number 

✓ Childproof cap 

✓ Health warnings (30% of pack)

Red Flags to Avoid

✗ Over 10ml with nicotine 

✗ Over 20mg nicotine strength 

✗ No TPD markings 

✗ Imported from US/China direct 

✗ No ingredient listing 

✗ Suspiciously cheap

Common Myths Debunked

"Vaping causes popcorn lung" 

Diacetyl has been banned in the UK since 2016. This only applied to some US products years ago.

"We don't know what's in it"

Every UK e-liquid ingredient is submitted to MHRA. It's more regulated than food.

"Antifreeze ingredient" 

PG is in antifreeze to make it LESS toxic. It's also in ice cream, cake mix, and asthma inhalers.

"Not tested for inhalation"

 All UK e-liquids require emissions testing. The vapour is analysed for harmful compounds.

The Bottom Line

UK vape juice contains four regulated ingredients that are tested before sale. It's not harmless - nothing you inhale is. But it's dramatically less harmful than the 7,000 chemicals in cigarette smoke.

If you smoke, switching to vaping could save your life. If you don't smoke, don't start vaping. Simple as that.

Last Updated: December 14, 2025

References

1. UK Government - E-cigarettes: regulations for consumer products (GOV.UK)

2. Public Health England - E-cigarettes: an evidence update (2015-2018)

3. Medicines and Healthcare products Regulatory Agency (MHRA) - TPD notifications

4. Royal College of Physicians - Nicotine without smoke: tobacco harm reduction (2016)

5. Cancer Research UK - Is vaping harmful?

6. NHS - Using e-cigarettes to stop smoking

7. Scientific studies on PG/VG safety (2017-2024)

8. House of Commons Library - The regulation of e-cigarettes (2025)