The general consensus in most candle making forums is that paraffin wax is toxic. Dangerous pollutants fill the air when you light a paraffin wax candle. The alternative is a natural wax, like soy or palm, that burns clean. After all, refined paraffin wax comes from the oil refinement process and is therefore a non-renewable resource.

There are still some candle makers familiar with the industry and it’s practices that claim paraffin wax isn’t dangerous at all! Their position is completely the opposite of those who say using that wax is damaging to the environment and the general population’s health.

Who are we to believe? With contentious subjects like this, the truth usually ends up being somewhere in the middle. This article explores the claims of both sides to bring light to the never-ending bickering of paraffin to understand the facts.

What is Paraffin Wax?

Way back in the ‘30s (the 1830’s, that is), a German scientist named Carl “invented” paraffin wax.  He also discovered/invented the Odic Force, but we’ll ignore that weird bit of history.  Carl’s work meant paraffin wax could be regularly be  derived as a byproduct of petroleum.  Admittedly that can sound frightening when we talk about burning that in our homes, but let’s stay the course and extract the truth.

Paraffin wax isn’t actually a direct product of petroleum.  The byproduct of oil refinement is actually called slack wax, which is a crude material with a high oil content.  Paraffin wax is what happens when slack wax gets transformed by chemists until it is fully-refined or semi-refined – generally an indication of how much oil is left in the wax.

As far as I can tell, there isn’t a good source to scientifically define “fully-refined” vs “semi-refined” paraffin wax, especially internationally, which may be part of the confusion around paraffin.  Some organizations have their own published standards, but it’s accepted (in the US, at least) that fully-refined waxes have an oil + moisture content less than 0.5%.

When it comes to candle making, many manufacturers will guarantee an oil content and whether or not the wax meets FDA requirements for contact with food sources.  If you’re purchasing paraffin wax from any major distributors in the US, it’s almost guaranteed the paraffin meets the common form of “fully refined” or even food-grade acceptance testing.  Why is that important? In addition to a lower oil content, fully-refined usually means the wax has the desired chemical properties for candle making (melting temperature, moisture content, etc).

Airborne Pollutants

Critics cite the “harmful emissions” of paraffin wax candles while they are burning.  A well known publication comes out of SC State by Dr Ruhullah Massoudi.  The claims in the news clipping are alarming and well distributed among critics of paraffin wax candles.  The study was later published in 2017 in the International Journal of Tropical Disease & Health and concluded the presence of airborne pollutants known to be harmful.  It doesn’t draw any conclusions beyond the presence of pollutants (such as concentrations and their known allowances), instead stating that the existence of known pollutants is enough to avoid paraffin candles.  It’s important to call out that those same pollutants are present in cigarette smoke and motor vehicle emissions.

All candles, whether natural or paraffin, operate in a combustion system – wax is melted, drawn up through the wick, and burned in the flame which creates a chemical reaction that is dispelled into the environment.  Paraffin candles, they say, create BTEX when burned: benzene, toluene, ethylbenzene and xylene (but not billie-jean), and they aren’t wrong.  BTEX are known carcinogens.

In 2014, an Italian study out of Italian Study by Politecnico di Milano, Campus Mancinelli (https://www.ncbi.nlm.nih.gov/pubmed/24318837) burned three cotton wick candles to determine the concentration of potential pollutants.  One was made of fully refined paraffin wax while the other two were made from slack wax. Remember how slack wax is much closer to the initial byproduct?  Not surprisingly, the two slack wax candles emitted significantly larger levels of BTEX than the fully refined paraffin candle. They found that the larger concentration of oil correlated to the BTEX emission levels.

They compared the measured levels to known thresholds published by organizations like World Health Organization and the United States EPA and found the fully refined paraffin wax never exceeded allowable BTEX concentrations while the two slack wax candles did exceed the allowable concentration with some of the pollutants. 

It’s not that the waxes have BTEX chemicals in the resting material – they’re actually products of incomplete combustion of the wax.  There’s a lot going on with a candle – read more about combustion here.

Fortunately it’s nearly impossible to find candle wax distributors selling anything less than fully refined paraffin (as well as we can define “fully refined”).  However, it should be cautioned that paraffin wax candles made with slack wax (or a high oil content paraffin) should be avoided, however unlikely it is to be found.

Soot

Soot is another component of candle burning that receives scrutiny.  Critics cite that soot is a risk for human respiratory health and cancer.  Unfortunately there haven’t been any studies that support the position that the soot given off by a candle is actually harmful – the closest study I could find that addresses it is from 1997 (Lau et al, cited by a 2001 EPA study) which didn’t measure any concerning levels of organic compounds (carbonous soot) in the air. 

It’s important to call out that if soot is concerning, the problem isn’t limited to paraffin – natural waxes create soot as well.  It’s a product of incomplete combustion – created when the waltz between the fuel, flame and oxygen skips a beat and the combustion balance is disturbed.

Lead

A pretty well-known study by the EPA in 2001 found that burning candles with a lead-core wick emitted other hazardous chemicals.  Fortunately, the candle professionals associated with National Candle Association agreed a long time ago to stop using lead-core wicks.  In 2003 lead-core wicks were banned by the United States Consumer Product Safety Commission making any modern-day struggles with old lead wicks a good excuse to buy some new candles.

It’s important to note that lead-core wicks are their own concern and have nothing to do with paraffin wax, but buying candles sourced from areas outside normal regulations should probably be validated for safety .

Fragrance

Like lead-core wicks, fragrances have nothing to do with paraffin wax.  It’s only proper to discuss the potential risks of fragrances included in a candle, paraffin or otherwise.  I didn’t dive deep for this one, but at first glance the research seems very inconclusive. This is likely due to the extreme variety in fragrance types and choices, but also because “fragrance” can be considered a trade secret.

The International Fragrance Association provides a manner of standardizing a trustworthy fragrance with some initiatives and standards, but this is completely abstracted by the time a consumer actually buys and burns a candle – fragrance supplies are oft undisclosed.  The loudest opinions I could find indicate that fragrances are not harmful, but the science is still waiting or too subtle for my reach (or particular interest at the time of this writing).

Conclusions

It would be foolish to think paraffin wax burns pure and clean, but it’s also hard to ignore not only anecdotal evidence of millions of candle users but also studies showing the levels of these toxins are evidently lower than safe standards published by WHO and US EPA.

Soot is the most obvious product of candle burning, a result of incomplete combustion in both paraffin and natural wax candles.  Nothing suggests beyond anecdote that soot from candles is a health risk. There’s some accepted opinion that claims soot from candles and soot created from other incomplete combustion activities share the same level of danger, but there isn’t much of a scientific foundation that the levels of pollutants or size of the particulate matter is anything to be alarmed by.

Lead-core wicks are a proven risk, but the industry responded in a fairly progressive way by banning them long before legally required.  Call that whatever you want, but the National Candle Association has a history (okay really just the one thing I called out) of making decisions in the interest of consumer safety and science.

At the end of the day it matters more that the candle burner is happy with whatever they’re buying, no matter the reason.  My family and friends don’t shy from using paraffin wax, but that doesn’t mean we’ll judge those who avoid it. A lot of research from both sides of the fully-refined paraffin wax aisle was discussed for you to form an opinion on it if you want – I simply wanted to present what’s out there for you to make a more informed opinion. 

The truth is usually somewhere near the middle when topics are as “heated” as paraffin wax seems to be in some circles of the industry.  Enjoy your candles!