But these chemicals, also called PFAS, arent inallwatch bandsso heres how to know what youre buying.

What did the recent study find?

Before we get into the specifics of watch-band shopping, lets put this into context.

The study found that perfluorohexanoic acid and other PFAS werepresentin many of the watch bands tested.

The researchers did not look for health effects on the people who wore the watch bands.

The researchers were able to extract a specific PFAS chemical, perfluorohexanoic acid, from several of the bands.

How dangerous are PFAS in watch bands?

The short answer is: We dont know.

There are also many different chemicals in the PFAS family and some may be more concerning than others.

But it may be a good idea to avoid bands with PFAS if you want to be cautious.

More studies on the health effects will hopefully come out in the future.

Which watch bands contain PFAS?

So you cant rely on brand names.

What youcanlook for is the material that the watch band is supposed to be made of.

Remember when I said that all the fluoroelastomer bands in the study appeared to contain PFAS?

What is the difference between fluoroelastomer and silicone watch bands?

Silicone watch bands arenotknown or suspected to contain PFAS.

They have a less sticky or dusty texture than silicone.

Many people prefer them, and they are generally more expensive than silicone bands.

Peaslee says if youre paying more than $30 for a rubbery-looking band, its likely to be fluoroelastomer.

(In the study, none of the bands under $15 tested positive for PFAS.

This is one place where it pays to be cheap.)

What should you look for when buying a band for your smartwatch or fitness tracker?

Peaslee hopes that with enough pressure from consumers, brands will start marketing products as PFAS-free.