New research reveals that many smartwatch and fitness tracker wristbands, particularly premium models, contain alarming concentrations of PFAS chemicals that could potentially seep into wearers’ skin. The study highlights specific concerns about a compound called perfluorohexanoic acid (PFHxA), found at unprecedented levels in some devices worn continuously against the skin.
Published in Environmental Science & Technology Letters | Estimated reading time: 4 minutes
In an era where tracking our daily steps and heart rate has become routine, researchers have uncovered an unexpected health consideration: the very bands we wear to monitor our wellness might be exposing us to significant levels of per- and polyfluoroalkyl substances (PFAS). These “forever chemicals,” known for their persistence in both the environment and human body, are particularly concentrated in higher-end watchbands made from fluorinated synthetic rubber.
“This discovery stands out because of the very high concentrations of one type of forever chemical found in items that are in prolonged contact with our skin,” says Graham Peaslee, the study’s corresponding author.
The research team from the University of Notre Dame analyzed 22 different wristbands across various brands and price points. Their findings revealed that all 13 bands advertised as containing fluoroelastomers – a synthetic rubber designed to resist sweat and oils – tested positive for fluorine, a key indicator of PFAS presence. More concerning was the discovery that two additional bands contained fluorine despite no mention of fluoroelastomers in their product descriptions.
The price point proved to be a significant factor, with bands costing over $30 containing higher fluorine levels than their sub-$15 counterparts. The most frequently detected compound, PFHxA, appeared in nine of the tested bands, with one sample containing over 16,000 parts per billion – a concentration that far exceeds levels typically found in consumer products.
“We have never seen extractable concentrations in the part-per-million range (>1000 ppb) for any wearable consumer product applied to the skin,” Peaslee notes. The implications of this finding are particularly concerning given the current limited understanding of how PFHxA interacts with human skin.
Lead author Alyssa Wicks offers practical advice for consumers, recommending the purchase of lower-cost silicone wristbands. For those seeking premium options, she emphasizes the importance of reading product descriptions and avoiding bands containing fluoroelastomers.
Glossary
- PFAS (Per- and polyfluoroalkyl substances): A group of synthetic chemicals known for their water and oil-repelling properties and environmental persistence
- Fluoroelastomers: Synthetic rubbers made from chains of PFAS, designed to resist discoloration and repel dirt
- PFHxA (Perfluorohexanoic acid): A specific type of PFAS compound found at high concentrations in many watch bands
Test Your Knowledge
What price point separated higher-concentration PFAS bands from lower ones?
Wristbands that cost more than $30 contained more fluorine than those under $15.
What material do researchers recommend as a safer alternative for watch bands?
Researchers recommend using lower-cost wristbands made from silicone instead of fluoroelastomers.
How many individual PFAS compounds did researchers test for in the watch bands?
The researchers tested for 20 different PFAS compounds in their analysis.
What was the highest concentration of PFHxA found in the study, and how does it compare to previous research?
The highest concentration exceeded 16,000 ppb, which was significantly higher than the median concentration of 200 ppb found in previous research on cosmetics.
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