
Choosing a traditional brake cleaner poses a rather unsatisfactory question. Do you choose the flammable highly toxic one, or the alarmingly very highly toxic one? It’s not such a nice question to consider and, of course, there is no good answer – or is there?
This article examines the conundrum facing buyers and users of brake cleaner. It also looks at some alternatives that rewrite the impossible question of “deadly or deadlier”.
Chlorinated v’s Non-Chlorinated Brake Cleaner
Standard brake cleaners can be divided into two main categories Chlorinated and Non-Chlorinated. Each type has its own positives but in each case these positives are far outweighed by the negatives. All this makes arriving at a rational choice between the two a wicked problem.
Chlorinated Brake Cleaner
Chlorinated brake cleaner has been around for the longest and still exists today even though its main ingredients have been banned in other applications. The term “Chlorinated” refers to the presence of Chlorine atoms in certain places within the molecular structure. These chlorine atoms help power the chemical’s solvent properties.
Tetrachloroethylene
Tetrachloroethylene (also called perchloroethylene or PERC) is an industrial solvent used for degreasing. Tetrachloroethylene is high performing, non-flammable and fast drying (through evaporation) which are all properties sought after in a brake cleaner.
Tetrachloroethylene is also highly toxic. It is a Group 2A carcinogen, which means that it is probably carcinogenic to humans and also a central nervous system depressant which can enter the body through respiratory or dermal exposure. It is also probably linked to Parkinson’s Disease.
At high temperatures (such as sparks) Tetrachloroethylene turns into extremely deadly Phosgene gas, which is a chemical weapon that kills in very low concentrations.
Methylene Chloride
Methylene Chloride (also called Dichloromethane) is often included along with Tetrachloroethylene to add additional properties to the mixture.
Symptoms of acute overexposure to Methylene Chloride via inhalation include difficulty concentrating, dizziness, fatigue, nausea, headaches, numbness, weakness, and irritation of the upper respiratory tract and eyes. More severe consequences can include suffocation, loss of consciousness, coma, and death.
Methylene Chloride may also be carcinogenic, as it has been linked to cancer of the lungs, liver, and pancreas in laboratory animals. In people with pre-existing heart problems, exposure to Methylene Chloride can cause abnormal heart rhythms and/or heart attacks, sometimes without any other symptoms of overexposure.
Non-Chlorinated Brake Cleaner
By definition, Non-Chlorinated brake cleaner is simply any brake cleaner that doesn’t contain chlorinated solvents. This distinction, however, does not make it safe and many of the chemicals used in these products are just as problematic.
Heptane
Heptane is sometimes used in brake cleaner. This chemical is distilled from oil and is highly flammable. It’s also toxic. Acute exposure to heptane vapors can cause dizziness, stupor, incoordination, loss of appetite, nausea, dermatitis, chemical pneumonitis, or unconsciousness. It’s is also very toxic to aquatic life with long-lasting effects.
The only upside to Heptane is that it has not yet been linked to cancer in lab animals or humans.
n-Hexane
n-Hexane is probably the most common ingredient and another example of a crude oil-derived product. N-Hexane is even more flammable than Heptane and tends to linger in workspaces creating potentially explosive vapour mixtures.
n-Hexane’s greatest problem, however, is its neurotoxicity. Workplace exposure has been shown to cause nerve damage in humans. It is particularly common in vehicle mechanics. Long term exposure to the chemical can lead to permanent numbness, tingling, weakness and reduced sensitivity.
So, What’s the Answer?
The choice between Non-Chlorinated and Chlorinated brake cleaner seems, at first, like a choice between bad and worse. The truth, however, is that this is a false dilemma.
Whilst the aforementioned chemicals are, by far, the most common ingredients in any brake cleaner you’re likely to find on the shelf, they are not your only options.
Low toxicity brake cleaners are available on the market today. Finding them in the shops or in your average supply catalogue can be difficult, however, so you need to do your research. What you may find interesting is that these low toxicity products actually outperform traditional toxic brake cleaners.

Purasolve Brake Cleaner
Purasolve Brake Cleaner is an ultra-safe residue-free cleaning solvent for brakes and other technical applications developed to replace highly toxic & explosive brake cleaners.
- High-Tech Safety Solvent
- Residue Free Finish
- Slow Evaporating
- Lasts 10 – 20 Times Longer than Conventional Brake Cleaners
- Safer for Health, Safety and the Environment
- Does not contain n-Hexane
- Does not Contain Chlorinated or Halogenated Solvents