"Paraffin candles are toxic" is one of the most repeated claims in candle making, usually from people selling a different wax. Rather than argue opinions, we pulled what the European Chemicals Agency (ECHA) actually records for paraffin wax. The short answer: refined paraffin wax carries no hazard classification in the EU. There are two real caveats, though: how well the wax was refined, and what any flame gives off.

What paraffin wax is, in ECHA's words

ECHA lists candle-grade paraffin as "Paraffin waxes and Hydrocarbon waxes", EC 232-315-6, CAS 8002-74-2. Its official description is a complex combination of hydrocarbons obtained from petroleum fractions by solvent de-oiling or sweating, made up mainly of straight-chain hydrocarbons longer than C20. It's a UVCB substance, not a single molecule, and "candle wax" is literally one of the names companies file it under.

What ECHA's records show

We queried ECHA's substance database and its Classification & Labelling (C&L) Inventory for paraffin wax and its closest relatives on 25 September 2026:

  • Paraffin waxes and Hydrocarbon waxes (EC 232-315-6): no harmonised classification in CLP Annex VI. Industry has notified 11 distinct self-classifications, and ECHA's headline (prominent) entry is "Not classified": no signal word, no pictogram.
  • Paraffin waxes (petroleum), hydrotreated (EC 265-154-5): no harmonised classification; prominent entry "Not classified".
  • Paraffin waxes (petroleum), clay-treated (EC 265-145-6): no harmonised classification; prominent entry "Not classified".
  • Microcrystalline wax (EC 264-038-1): no harmonised classification; prominent entry "Not classified".

A harmonised classification is the EU-wide, legally binding verdict, and it's where the serious hazards (carcinogens, mutagens, reproductive toxicants) get fixed. None of the refined wax grades has one. Registrants' own self-classifications agree: refined paraffin wax isn't hazardous as a substance.

The catch: refining

The scary version of the story isn't invented. It's about a different material. Look one step back in the refinery and ECHA's records change sharply:

  • Slack wax (petroleum) (EC 265-165-5, index 649-244-00-5): harmonised Carc. 1B, H350 "May cause cancer", signal word Danger.
  • Petrolatum (EC 232-373-2, index 649-254-00-X): the same harmonised Carc. 1B, H350.

Slack wax is the crude, oil-rich wax that paraffin is refined from. The concern is the residual oil and the polycyclic aromatic hydrocarbons that can come with it. That's why these Annex VI entries carry Note N: the carcinogen classification doesn't apply when the full refining history is known and the substance it's made from isn't a carcinogen. Refining is exactly what separates a Carc. 1B slack wax from a "not classified" candle wax.

In practice, buy fully refined paraffin from a supplier who'll give you a safety data sheet. Check Section 3 for EC 232-315-6 (or one of the refined grades above) and Section 2 for "not classified". If an SDS names slack wax or shows H350, you're holding a different product.

What about burning it?

A classification describes the wax as a substance, not what comes off a flame. Any candle, whether paraffin, soy, rapeseed or beeswax, burns to carbon dioxide and water, and when combustion is incomplete it also gives off soot and small amounts of volatile organic compounds. That comes from the flame, not from paraffin specifically.

The evidence on real exposure is reassuring. A peer-reviewed risk assessment published in Regulatory Toxicology and Pharmacology in 2014 (Petry et al.) measured emissions from scented candles made from different waxes and found them below health-based indoor-air guideline values. The much-shared 2009 claim that paraffin candles release harmful chemicals came from a conference presentation, not a peer-reviewed paper. What does change emissions is how the candle burns: a wick sized to the vessel, a trimmed wick, no draughts. The EN 15426 standard exists to test candles for exactly that sooting behaviour.

What this means for your label

Because refined paraffin wax is not classified, it adds nothing to your candle's hazard classification. Soy and rapeseed wax usually add nothing either. The wax isn't what puts pictograms on a candle. The fragrance is: its allergens and sensitisers, at your chosen load, decide whether you need a CLP label and which allergens go on the EUH208 "Contains…" line. Switching from paraffin to soy won't change that label. Changing the fragrance or the load will.

Check any ingredient the same way

Every figure in this article came from ECHA's live databases, which are the same sources Molekule queries for each component of your formula. Upload your wax and fragrance safety data sheets, and Molekule checks each substance against ECHA's harmonised and industry classifications, then builds the finished candle's CLP label from the result. Check your candle's ingredients in Molekule.