Smartwatches have become a staple for tracking steps, monitoring heart rate, and staying connected throughout the day. But while you’re focused on optimizing your health, your smartwatch band could be silently doing the opposite—exposing you to high levels of toxic chemicals known to cause long-term damage to the body.

A recent Notre Dame study found that 15 out of 22 smartwatch bands tested contained dangerously high levels of PFAS (Per- and Polyfluoroalkyl Substances), also known as forever chemicals. These compounds are widely recognized as some of the most persistent and harmful toxins in the environment and the human body.^[1]

PFAS are commonly associated with non-stick coatings like Teflon, but they are also added to some smartwatch bands to repel dirt, oil, and sweat. The result? A cleaner-looking watch band—but at the expense of your health.

How PFAS from Your Smartwatch Band Enters Your Body

PFAS chemicals are particularly concerning because they don’t break down easily. They accumulate in the body over time and have been linked to severe health issues, including hormone disruption, immune dysfunction, and even cancer.

Smartwatch bands made with fluoroelastomers, a synthetic material similar to silicone, contain at least one type of PFAS. These bands are marketed for their durability and resistance to heat, oils, and chemicals, but that durability comes with a toxic tradeoff.^[2]

Here’s why this matters:

• PFAS and other toxic compounds are absorbed directly into the skin through the thin, sensitive skin on the wrist.
• The PFAS levels in smartwatch bands are significantly higher than in many other consumer products, meaning direct skin contact can increase absorption.
• Wearing these bands daily results in chronic, low-dose exposure, which builds up in the body over time and contributes to long-term health issues.

The Hidden Health Risks of PFAS Exposure

PFAS chemicals have been extensively studied, and the findings are alarming. Research has linked PFAS exposure to:

• Liver and kidney damage – PFAS accumulates in these detox organs, impairing their ability to filter toxins and leading to long-term organ dysfunction.^[3]
• Immune system suppression – Studies show that PFAS exposure reduces the effectiveness of the immune response, making the body more vulnerable to infections and diseases.^[4]
• Hormone disruption – PFAS interferes with endocrine function, impacting everything from metabolism to reproductive health.^[5]
• Increased cancer risk – The Environmental Protection Agency (EPA) and other health organizations have identified certain PFAS compounds as probable carcinogens, meaning they may increase the risk of cancers such as kidney, liver, and testicular cancer.
• Developmental issues in children – Pregnant women exposed to PFAS may pass these chemicals on to their developing babies, increasing the risk of birth defects and developmental disorders.^[6]

PFAS’s ability to persist in the body for years makes it particularly dangerous, meaning even small, daily exposures can add up over time.

What’s Really in That “Silicone” Smartwatch Band?

If you’ve ever purchased a smartwatch band marketed as “silicone” or “silicone-like,” there’s a high chance it’s not actually made from pure silicone. Many of these bands are instead made with fluoroelastomers, a synthetic rubber designed for extreme durability.

Fluoroelastomers are often used in high-performance applications like aerospace, automotive manufacturing, and industrial machinery—places where resistance to heat, oil, and chemicals is a priority. But should we really be wearing these industrial-grade materials against our skin 24/7?

Many smartwatch brands, including Apple and Fitbit, use fluoroelastomers for their sports bands. While these bands are praised for their comfort and longevity, the reality is that they can contain multiple toxic compounds, including PFAS, heavy metals, and chemical additives that enhance their flexibility and resistance to degradation.

If your watch band claims to be:

• Soft and flexible but extra durable
• Heat and water-resistant
• “Silicone-like” but not explicitly labeled as 100% silicone

It’s likely made from fluoroelastomers, which could expose you to toxic substances every time you wear it.

Safer Alternatives: What to Wear Instead

The good news is that you don’t have to ditch your smartwatch entirely. Swapping out your watch band for a safer material can drastically reduce your exposure to harmful chemicals.

Here are some better alternatives:

• 100% stainless steel watch bands – Stainless steel is a safe, non-toxic material that doesn’t contain PFAS, plasticizers, or synthetic chemicals. Look for mesh or solid-link stainless steel options for a comfortable, breathable fit.
• 100% leather watch bands – Leather is a natural material that doesn’t off-gas synthetic chemicals. Just be sure to choose vegetable-tanned leather rather than chemically treated leather, which may contain additional toxins.
• Fabric or nylon watch bands – While some synthetic fabrics may contain chemical coatings, choosing untreated, organic cotton or nylon options can be safer than fluoroelastomer or silicone-based bands.

How to Avoid PFAS in Watch Bands and Other Wearables

Even if your smartwatch band claims to be “100% silicone,” it’s best to proceed cautiously. Many manufacturers use misleading marketing terms to make synthetic materials sound safer than they are.

Here’s how to avoid exposure:

• Check the materials carefully – Look for 100% stainless steel, untreated leather, or fabric options instead of fluoroelastomers or soft plastic bands.
• Avoid bands labeled “fluoroelastomer” – These are known to contain PFAS and other synthetic additives.
• Be wary of vague descriptions – If a band is advertised as “silicone-like,” it is likely not pure silicone and could contain chemical additives.
• Replace synthetic bands with safer alternatives – The longer you wear a fluoroelastomer band, the more exposure you’ll get. Swapping it out for a safer material is a simple way to reduce daily contact with toxins.

Final Thoughts

Your smartwatch is supposed to help you track your health—not quietly expose you to toxic chemicals that undermine it. The growing evidence against PFAS and fluoroelastomers shows that some of the most popular smartwatch bands on the market are far from safe.

By choosing non-toxic alternatives like stainless steel, leather, or fabric bands, you can minimize your exposure to PFAS and other harmful substances while still enjoying your smartwatch’s benefits.

Toxic exposure often comes from the most unexpected sources. But by staying informed and making small swaps, you can protect your health in ways that truly matter.

References:

1. Sieff, Jessica. “Researchers Detect Elevated Levels of PFAS in Some Fitness Tracker and Smartwatch Bands.” Notre Dame News, 18 Dec. 2024, https://news.nd.edu/news/researchers-detect-elevated-levels-of-pfas-in-some-fitness-tracker-and-smartwatch-bands/.
2. Wacławik, Małgorzata, et al. “Silicone Wristbands in Exposure Assessment: Analytical Considerations and Comparison with Other Approaches.” International Journal of Environmental Research and Public Health, vol. 19, no. 4, Feb. 2022, p. 1935.
3. Fenton, Suzanne E., et al. “Per- and Polyfluoroalkyl Substance Toxicity and Human Health Review: Current State of Knowledge and Strategies for Informing Future Research.” Environmental Toxicology and Chemistry, vol. 40, no. 3, Mar.
4. Bline, Abigail P., et al. “Public Health Risks of PFAS-Related Immunotoxicity Are Real.” Current Environmental Health Reports, vol. 11, no. 2, 2024, pp. 118–27.
5. González-Alvarez, María Estefanía, et al. “Effects of Per- and Polyfluoroalkylated Substances on Female Reproduction.” Toxics, vol. 12, no. 7, June 2024, p. 455.
6. Starling, Anne P., et al. “Prenatal Exposure to Per- and Polyfluoroalkyl Substances and Infant Growth and Adiposity: The Healthy Start Study.” Environment International, vol. 131, Oct. 2019, p. 104983.