14

Some chain lubricants contain fluorocarbons like PTFE or other substances called PFAS. Is this a genuine environmental issue? Should I avoid all lubricants containing fluorocarbons?

I have heard that in ski waxes, fluorocarbons are starting to become forbidden. Should the same fluorocarbon ban apply to bicycle chain lubricants too?

4
  • I wouldn't worry too much about PTFE. Yes, it lasts forever, but that's because nothing reacts with it.
    – Mark
    Commented Jun 14, 2023 at 2:09
  • 1
    @Mark Research is ongoing regarding the health and safety aspects of PTFE use. Its chemical inertness doesn’t excuse it from potentially being dangerous. At the very least, it can serve as a micro plastic which never breaks down, running the risk of mechanically clogging blood vessels and whatnot if introduced into the body.
    – MaplePanda
    Commented Jun 14, 2023 at 4:53
  • @Mark From the link I gave in my answer: In 2018, the European Food Safety Authority (EFSA) re-evaluated the multiple lines of evidence of PFOA and PFOS toxicities, which resulted in significantly lower provisional ‘safe’ limits, known as the ‘tolerable weekly intake’ (TWI) (EFSA, 2018). The assessment concluded that a considerable proportion of the European population is expected to exceed the TWI due to intake of PFAS from food and drinking water. There's also an infographics from the US National Toxicology Program with the potential effect in some diseases/cancers.
    – Rеnаud
    Commented Jun 14, 2023 at 6:54
  • @Renaud, PFOA and PFOS both have functional groups tacked on to the carbon chain, which makes them far more reactive than PTFE, which is just straight carbon and fluorine.
    – Mark
    Commented Jun 14, 2023 at 8:45

2 Answers 2

10

The European Environment Agency has declared that PFAS are an emerging chemical risk. As indicated in this page, the effects of this components is not yet entirely understood, but there negative known effects, and this kind of pollutant does not degrade over time.

There are alternatives, maybe not as good/convenient. If you hesitate and care about the environmental impact, I would answer by this question by the precautionary principle, not by computing the mass that is produced to cover the needs of "cycling".

Note that cycling may be a minor contributor in relative terms, but may have an bigger impact than other sectors, such as cookware, because cycling happens outdoor, and the chemicals released go straight in the environment. This kind of factor is not taken into consideration if you only look at the mass.

5
  • What are the environment friendly alternatives? Do they turn black after usage?
    – Ender
    Commented Jun 13, 2023 at 5:47
  • 2
    The alternatives are PFAS-free lubricants. Turning black after usage is linked to ambiant contamination, the only way to avoid it I'm aware of is to use wax instead of liquid lubes.
    – Rеnаud
    Commented Jun 13, 2023 at 5:52
  • I've checked what is available. Finish Line chain wax has molybdenum. I think it is better than PFAS.
    – Ender
    Commented Jun 13, 2023 at 6:22
  • 1
    Molybdenum is a nutrient for plants, so definitely better (if not in excess, as usual, but unlikely that it would be case with residues from bike chains).
    – Rеnаud
    Commented Jun 13, 2023 at 7:10
  • 1
    @Ender Molybdenum is also one of the replacement ingredients for PFAS in ski waxes. It should be better. Commented Jun 13, 2023 at 13:33
3

Firstly, we need to know how much fluorocarbons are released to the environment. In European Union, 75 kilotonnes of PFAS end up in environment. So, to estimate if bicycling is a major contributor to this, we need to calculate the percentage of PFAS that would be emitted by bicyclists should every bicyclist use PFAS lubricants.

As examples of fluorocarbon-containing chain lubricants, the Rex Black Diamond and Domestique chain lubricants apparently contain fluorocarbons. They are sold in 30 gram bottles, good for 30 applications. From this we know that 1 gram per application is used.

We also need to estimate how much fluorocarbons are contained in a gram of this lubricant. I was unable to find any information. However, I was able to find that Mspeedwax contains 5 grams of PTFE per 500 grams of wax, or 1 percent. However, it's likely that Mspeedwax is a very low-PTFE wax, since they confirm this small amount is going to be phased out. By pouring Rex Black Diamond into a disposable shot glass, I definitely see it's mostly liquid oil and not solid fluorocarbons, so I'd estimate this lubricant probably contains 5 percent solids (fluorocarbons).

I was able to find information that the average Finnish person rides bike 234 km/year. (I was unable to find EU-wide statistics for this.) European union has a population of 447.7 million, so about 104.8 billion kilometers/year are ridden in EU.

Rex says that a single application of its lubricants lasts 500 km. However, Zero Friction Cycling got 5602 km in a lab and estimate that in real-world conditions you would get 1867 km. My experience also is that even a very cheap chain lubricant easily lasts 800 km, so let's say a single lubrication lasts 1000 km.

So, 104.8 million lubrications per year are needed in EU. Each lubrication of 1 gram contains probably 0.05 grams of fluorocarbons. Therefore, 0.00524 kilotonnes of fluorocarbons would be released to environment should every cyclist use these fluorocarbon containing lubricants. That's 0.007% of the total PFAS emissions. Very insignificant.

However, it should be remembered this applies to wet lubricants that last a really long time and consist mostly of oil (with little bit of fluorocarbons extra). A dry lubricant that contains lots of fluorocarbons as the sole lubricant and some evaporating solvent needs to be applied far more often and contains more fluorocarbons, so the results could be even two orders of magnitude worse. Still, if every cyclist would use these horrible dry lubricants, cycling would still create only 0.7% of the PFAS emissions.

About ski waxes: 15 grams will wax 1-2 pairs of adult skis. Let's say 2, so 7.5 grams per pair are used. However, a lot of this could be wasted: it has been measured that a single ski has only about 1.1 g of wax remaining. That's 2.2 g per pair. One waxing endures 40 kilometers, so this means 55 grams of wax are used per 1000 km. You can contrast that to bicycling which uses 1 gram of chain oil per 1000 km.

So skiing leaves behind 55 times the amount of wax than cycling leaves the amount of chain oil, per kilometer. Thus, it can't be said that the fluorocarbon ban in ski waxes should be extended to cycling as so little chain oil is left behind.

7
  • 7
    What are considered the acceptable levels in the environment. "I pollute less than he do, so I do not need to change" is poor justification for continuing to do something that is bad for the environment (and largely how the world got into the mess it is).
    – mattnz
    Commented Jun 12, 2023 at 19:29
  • 3
    MSW's current formulation already eliminates PTFE. Also note that PTFE has environmental implications when it's being manufactured. These may outweigh the damage from releasing it into the environment.
    – Weiwen Ng
    Commented Jun 12, 2023 at 21:08
  • 2
    My biggest gripe against wet lube is dust/mud contamination, as wet lube is a magnet for particles — I ride off-road, but not the technical style, which includes a lot of dolomite "roads". Do not forget that zero friction cycling results are lab results. In practice, I have to clean my chain much more when using wet lube than dry lube because of that.
    – Rеnаud
    Commented Jun 13, 2023 at 5:40
  • 3
    @mattnz perhaps you could say the world got into the mess it is because of self-amplifying loops "Alice pollutes, so I might as well do too" - "Why should I stop polluting, Bob is doing it as well" - "Alice and Bob are both driving cars every day, so what does it matter even if I get that dirty SUV" - "Hey, Charlie got an SUV, I want one too"... Stopping this kind of tragedy is important, but OTOH denying old Daisy her Prius that she needs to get her shopping done every two weeks really would not make sense as it has quite negligible impact compared to the others. Commented Jun 13, 2023 at 7:21
  • 2
    @mattnz on the other hand "I pollute an order of magnitude less" means that eliminating my tiny bit of usage would be rounding error, and my finite efforts would better be spent elsewhere.
    – Chris H
    Commented Jun 13, 2023 at 15:22

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.