A new laboratory investigation has raised alarm over hazardous substances in headphones – including products from major brands such as Bose, Samsung and Sennheiser, according to a report by The Guardian. Every pair of the 81 models tested contained toxic chemicals linked to serious health concerns, a finding that experts warn could affect millions of users worldwide.
All headphones tested contain harmful chemicals
Researchers from the ToxFREE LIFE for All project, a partnership of civil society groups in Central Europe, analyzed both over-ear and in-ear headphones purchased in retail stores and online marketplaces. Laboratory tests found bisphenols such as BPA (bisphenol A) and BPS (bisphenol S) in the vast majority of samples – BPA was detected in 98% of them, and BPS in more than three-quarters. These chemicals are widely used as plastic additives but are known endocrine disruptors.
In addition to bisphenols, the study identified phthalates (associated with reproductive toxicity), chlorinated paraffins (linked to liver and kidney damage in animal studies), and various brominated and organophosphate flame retardants. Many of these substances are associated with hormone disruption, cancer risk, and neurodevelopmental issues, raising concerns about long-term exposure.
While many of these chemicals were found in trace amounts, experts say that prolonged contact – especially through sweat and heat during exercise – can increase migration into the skin. “Daily use – especially during exercise when heat and sweat are present – accelerates this migration directly to the skin,” said a chemical expert involved in the project.
Headphones have evolved from occasional accessories to everyday essentials, worn for hours at work, during workouts and in relaxed settings. That extensive, often close contact with the skin has drawn scrutiny because it provides a pathway for chemical migration. Endocrine-disrupting substances like BPA mimic natural hormones and have been implicated in various health problems, including developmental disorders and cancer.
For consumers, the finding underscores a broader concern about chemical exposure from everyday products. Bisphenols and similar plastic additives have been subjects of regulatory scrutiny for years due to their ability to leach out of materials and interact with biological systems. Although individual doses from headphone plastics may be low, scientists point out the possibility of a “cocktail effect” – where continuous exposure to multiple sources of hazardous substances over time compounds health risk.
Brand response and public awareness
Major audio brands named in the study did not provide immediate responses to requests for comment. The lack of transparency about the materials used in consumer electronics has drawn criticism from health advocates, who argue there is a “market-wide failure” to disclose potentially harmful substances to buyers.
The findings add to a series of recent investigations by ToxFREE, including earlier work that detected bisphenol A in baby products and other everyday textiles. The research groups have called for broader regulation and bans on endocrine-disrupting chemicals in consumer goods to protect public health – particularly for vulnerable groups like children and teenagers who may be more susceptible to hormonal effects.
Health experts emphasize that more research is needed to quantify real-world exposure levels and actual health impacts from chemicals in headphones. Regulators and consumer safety groups may pursue new testing standards or labeling requirements for wearables to ensure users are better informed about material contents.
In the meantime, consumers may begin to demand greater transparency from manufacturers and push for safer materials. The study’s results spark an important conversation about the hidden chemicals in products we wear close to our bodies – and how everyday tech could have unexpected implications for long-term health.