When we started making candles, we picked soy wax partly because we thought paraffin was bad for you. Petroleum-based, toxic fumes - everyone says it. We said it too. We even had a blog post listing it as one of our top reasons for choosing soy.

Then we actually read the research.

What the science says

In 2007, the Bayreuth Institute of Environmental Research in Germany ran the most extensive candle emissions study ever conducted. They tested candles made from paraffin, soy, stearin, palm and beeswax, analysing emissions for over 300 chemicals - dioxins, volatile organic compounds, benzene, formaldehyde, the lot.

The findings:

• All five wax types produced virtually identical emissions
• Every reading came in at less than 2% of the strictest indoor air quality standards
• No benzene was detected in any properly wicked candle, regardless of wax type
• No significant difference between any of the waxes tested

The study was funded by a global consortium of European and American candle industry bodies and carried out independently by Ökometric GmbH. It remains the most comprehensive research on candle emissions to date.

What about soot?

You might have noticed paraffin candles soot more. That's usually a wicking issue - paraffin burns hotter, so the wrong wick makes it worse. Any candle with the wrong wick will soot. A well-made one won't.

So why do we use soy?

The toxic argument doesn't stack up. We know that now. But soy still wins where it matters to us.

Renewable and plant-based. Soy comes from soybeans, not petroleum. A crop that regrows, not a finite resource.

Lower burn temperature. Cooler flame, longer burn time and a more gradual scent release. You get more hours from the same candle.

Biodegradable. Spill soy wax on a table or fabric? Warm soapy water. Done. Try that with paraffin.

We'd rather tell you the real reasons we chose soy than repeat a myth that sounds good. We got this one wrong for years. Now you know what we know.

This post is part of our Mythbusting series, where we look at common candle and home fragrance beliefs and check them against the evidence. Some will surprise you.

Source: Ökometric Wax and Emissions Study (2007), Bayreuth Institute of Environmental Research, Germany. Full report available via Candles Europe.