The debate between soy wax and paraffin candles generates a lot of strong opinions and very little cited evidence. Most articles on the subject repeat the same claims without referencing where those claims come from. This article does things differently — we look at what the research actually says, what it does not say, and what it means for you as a candle buyer.
What paraffin wax is
Paraffin wax is a byproduct of petroleum refining. It is the most widely used candle wax in the world, primarily because it is cheap, widely available, and easy to work with at scale. The vast majority of mass-market candles — including many sold as premium products — are made from paraffin.
What soy wax is
Soy wax is derived from soybean oil, making it a renewable, plant-based material. It was developed as a candle wax in the 1990s as an alternative to paraffin, and has been adopted widely by independent candle makers in the UK and US.
What the research says about emissions
The most frequently cited study on candle emissions is a 2007 investigation by researchers at South Carolina State University, led by Dr. Ruhullah Massoudi. The study tested a range of candle types and found that paraffin candles released potentially harmful chemicals including toluene and benzene — both known carcinogens — when burned. Soy and beeswax candles did not produce these chemicals at detectable levels in the same tests.
The study was peer-reviewed and published in the journal Chemosphere. It is the most rigorous published comparison of paraffin and soy candle emissions available, and its findings have been replicated in subsequent independent testing.
It is worth being precise about what this means. The levels of chemicals detected in the South Carolina study were described by the researchers as potentially harmful with prolonged exposure in an unventilated space — not as immediately dangerous from normal candle use. The study does not suggest that burning a paraffin candle occasionally is a health risk. It does suggest that regular, sustained exposure in poorly ventilated rooms may be worth considering.
What the research does not say
No peer-reviewed study has concluded that burning paraffin candles in normal domestic conditions causes measurable harm to human health. The evidence base for strong health claims about paraffin candles is limited, and some claims made in the candle industry go well beyond what the research supports.
Similarly, soy wax is not without nuance. Most commercial soy wax is a blend rather than pure soy, and the environmental credentials of soy depend heavily on sourcing — soy agriculture has been linked to deforestation in some regions. UK-sourced or responsibly certified soy wax is a meaningfully different product from commodity soy.
Burn performance: what actually differs
Setting aside the health debate, there are practical differences between soy and paraffin that are well established:
- Burn time: Soy wax burns more slowly than paraffin at equivalent weights, typically giving 25–50% longer burn times. This is because soy has a lower melting point and releases fragrance more gradually.
- Scent throw: Paraffin has historically been considered superior for hot scent throw — the strength of fragrance when the candle is burning. Modern soy formulations have closed this gap significantly, though the difference remains a matter of debate among makers.
- Soot: Soy candles produce less soot than paraffin candles when burned correctly. Soot production in any candle is also heavily influenced by wick size and trimming — an untrimmed wick on a soy candle will produce more soot than a well-maintained paraffin candle.
- Clean-up: Soy wax is water-soluble and cleans up easily with soap and warm water. Paraffin requires solvents to remove properly.
Why we use soy wax
At The Victorian Candle Co., we use 100% soy wax in all of our candles, made in our workshop on Lowther Street in Carlisle. We chose soy for three reasons: the cleaner burn profile, the longer burn times it gives our customers, and the fact that it is a renewable material rather than a petroleum byproduct.
We are also transparent about what soy wax is and is not. It is a better choice than paraffin for the reasons above. It is not a miracle material, and we would rather give you an honest account of the evidence than repeat claims that go beyond it.
If you want to understand more about how our candles are made, read our guide to what handmade actually means, or find out are soy candles better for your health for a deeper look at the wellness angle. You can also explore our full range of hand poured soy wax candles or compare beeswax candles vs soy candles if you are weighing up your options.
The bottom line
Soy wax burns cleaner, lasts longer, and is derived from a renewable source. The research supports a meaningful difference in emissions between soy and paraffin, particularly with sustained exposure. For occasional use in a well-ventilated room, the health difference is unlikely to be significant. For everyday use, soy is the better choice — and the evidence backs that up.