A recent California lawsuit suggests that Apple knowingly sells Watch bands that contain PFAS. This follows on from a 2024 study that found significant PFAS in many of the 22 armbands they tested. So, what’s the truth? And what is the potential harm?
PFAS -the asbestos of our time
PFAS substances are a large group of highly durable manmade chemicals. These chemicals are big business because they offer almost unique properties. They can be non-stick, water proof, stain repellent, grease proof, and heat resistant. No other class of compounds offers such a wide range of useful properties.
PFAS has been used in all manner of applications. Some of the common ones include:
- Non-stick cookware and bakeware
- Grease resistant coatings on fast food packaging
- Stain resistant coatings on carpets
- Breathable waterproof membranes
But they also crop up in all sorts of unlikely places. PFAS have been found in diapers, cosmetics, dental floss, and even contraceptives.
The problem with PFAS
Over recent years, PFAS has gone from miracle-substance to being demonized as people learn about its negative effects. Since the 1990s, scientists have known that PFAS causes major environmental pollution because it's so hard to break down. This led to the term “forever chemicals”. But PFAS is also linked to an ever-increasing range of serious health issues. These include kidney cancer, inflammatory conditions, impotence, immunosuppression, cardiovascular disease, and many many more. Now, attention has turned to PFAS in fitness trackers and smart watches.
The smart watch revolution
In the past decade, smart watches and fitness trackers have become seriously big business. The first Apple Watch launched in 2015. Initially, uptake was low. But by 2022 around 130M units were being sold each year. And the overall market was around half a billion units that year. That’s a staggering number of devices getting sold, beaten only by smartphones. There are many variations in these wearable devices, but nearly all of them are based on a classic wrist watch form factor. The actual device unit has sensors on the back and a display on the front. It is worn using a band or strap that is typically replaceable. These bands are made of a variety of materials including silicon, metal, leather, and fluoroelastomer.
PFAS in smartwatch bands
A 2024 study looked at a total of 22 different watch bands from different manufacturers. They found that 15 of the bands contained high levels of fluorine indicative of the presence of fluoroelastomer. They then further analyzed the bands and found that a majority of them contained Perfluorohexanoic acid (PFHxA), a well-known PFAS.
Fluoroelastomer-the upmarket alternative to silicon?
The crazy thing is that fluoroelastomer is marketed as a better alternative to traditional silicon or latex rubbers. It is generally more stable, grease-resistant, and comfortable to wear. In a report in the UK Guardian newspaper, one of the co-authors of the study is reported as saying:
“Some of the brands advertise that they use PFAS in the bands – the term “fluoroelastomer band” indicates their use. [...] Those that include PFAS were as much as $50 more than those that did not, Peaslee said. “It’s pretty clear that they are charging extra for all this beautiful PFAS.”
PFAS is absorbed through the skin
Worryingly, another study last year reported that PFAS may be readily absorbed through the skin. Your smartwatch armband is likely to be a key source of PFAS absorption since you wear it almost continuously, including during sports. This means you might want to think about swapping your watch band for a PFAS-free alternative!
What can you do about it?
By now, like me, you might be regretting buying a fluoroelastomer band for your Apple Watch. So, what can you do? Well, clearly you should look for an alternative that is PFAS-free. But beware, as the study reveals, this isn’t always straightforward. Leather straps should be PFAS-free. But they may well have a PFAS-based coating to preserve or waterproof the leather. Silicon bands should be PFAS free, but there are quite loose rules defining what can be marketed as silicon. Nylon straps may have PFAS coatings to make them stain- and water-resistant. Never has “buyer beware” been more appropriate! Probably your safest bets are a metal band. Alternatively, a nylon or leather strap that isn’t marketed as waterproof or stain resistant (unless it is guaranteed as PFAS-free).
