Some European retailers have stopped selling certain headphones after an EU-funded study found that they contained hormone-disrupting chemicals.
The study included leading brands such as Apple, Beats, Samsung, Bose, JBL, and Sennheiser. Online stores Bol.com, Coolblue, and Mediamarkt didn’t respond to inquiries from The Verge about which headphones they pulled, but local news outlets report that they’re among the retailers that have decided to yank some of the worst-scoring models off the market.
The study authors analyzed 81 different types of headphones, and found that all of them contained at least traces of harmful chemicals including bisphenols, phthalates, and flame retardants. These are endocrine-disrupting chemicals linked to reproductive health issues, neurobehavior problems, and other health risks.
“We really think a systemic approach in banning and phasing out the most harmful chemicals — which have generational effects — is the way forward”
And while the chemicals were found in low concentrations, their prevalence in the headphones studied shows how widespread and overlooked their use can be. It also raises questions about the cumulative toll products laced with these substances might take on more vulnerable individuals, including children, teens, and pregnant people.
“We really think a systemic approach in banning and phasing out the most harmful chemicals — which have generational effects — is the way forward,” says Karolína Brabcová, a campaign manager on toxic chemicals in consumer products at the Czech nonprofit Arnika who coauthored the report.
Brabcová and her colleagues produced the report as part of the ToxFree LIFE for All project along with four other consumer advocacy groups based in the Czech Republic, Slovenia, Hungary, and Austria. The project has received a roughly 2 million-euro grant from the EU.
To conduct this study, the researchers disassembled the headphones to collect 180 samples of hard and soft plastics from products marketed for adults, teens, and children. A lab analyzed the samples to look for the hormone-disrupting chemicals in products made by more than 50 different brands.
They gave each set of headphones three scores for parts that touch the skin, parts not touching the skin, and a total product evaluation. For each category, the headphones were rated either green for “lowest risk,” yellow for being “legally compliant but exceeding stricter voluntary limits,” or red for “high concern.” Samples that were “non-compliant with legal limits or contain[ed] multiple hazardous substances” got a red rating. But the report doesn’t disclose exact numbers for how much of each substance was found in each sample, only which chemicals were identified.
Apple’s AirPods Pro 2 and JBL’s Tune 720BT received green ratings across the board, for example. But there were also varied results between individual products tested that were made by the same brand. JBL’s Wave Beam and JR310BT, which are headphones for kids, both got red scores for parts not touching the skin and in the total product evaluations. HP’s HyperX Cloud III gaming headset and Razer’s Kraken V3, meanwhile, both scored red across all three categories.
The Verge reached out to 11 of the major manufacturers included in the study. Only Bose, Sennheiser, and Marshall responded; they all say that their products comply with legal safety requirements.
The companies also questioned the methodology used in the study. “It is unclear what facts the lab used to reach its conclusions,” Bose spokesperson Joanne Berthiaume said in an email. Sennheiser spokesperson Eric Palonen said that the company contacted the report authors “hoping to get the exact data for the Sennheiser products tested in order to verify our data and decide on next steps,” but that the organization didn’t provide the data it requested.
“There’s no imminent danger”
“The study used its own testing criteria and flagged the product based on thresholds for BPA-related substances that are stricter than those typically applied to plastics used in electronic products,” Anna Forsgren, product compliance and sustainability manager at Marshall Group, said in an email. Forsgren also mentioned that the company “welcome[s] reports like this as they drive greater transparency and accountability in the industry.”
Brabcová says that several manufacturers reached out to Arnika to ask about how it conducted the study. Although the group declined to confirm which companies had been in touch, Brabcová sees their interest in the report as a sign that companies are thinking about how they can improve their products.
The goal wasn’t to rank the headphones or even dissuade consumers from purchasing certain products mentioned, Brabcová tells The Verge. After all, the chemicals were found in low levels in samples. “There’s no imminent danger from using those [headphones] and again these are minuscule concentrations,” Brabcová says.
Instead, Brabcová and her colleagues want to call attention to the many ways consumers are exposed to these chemicals in their day-to-day lives, and the cumulative risk that creates. “Even in a small product like headphones, there’s a cocktail of chemicals which people might be exposed to. And now, multiply it by 100 because we use hundreds of products a day,” she says. These headphones also become e-waste eventually, which might release the chemicals into the air when burned or seep into water sources from landfills.
“The idea is you do not want to get a high exposure from here and there and everywhere,” says Aimin Chen, a professor of epidemiology at the University of Pennsylvania’s Perelman School of Medicine, who was not involved with the study. “If you can reduce exposure, it’s always good.”
Bisphenols are commonly used to bond plastic or metal parts, and to provide thermal insulation for printed circuit boards and batteries. The most notorious type of this chemical, BPA linked to developmental risks for children, was found in 98 percent of the headphone samples. Phthalates are widely used to make plastics more pliable and to add scents to personal care products. About 60 percent of the samples in the study contained small amounts of phthalates considered carcinogenic, mutagenic, or reprotoxic.
“You do not want to get a high exposure from here and there and everywhere”
Chen notes that the report from Arnika and its partners doesn’t go as far as to show how much exposure to these chemicals a person might get from wearing certain headphones — just that the chemicals are in the devices. It would take further research, controlled studies, to see how much of a substance might enter the human body through skin contact or from unwittingly ingesting dust from the product.
Part of the concern with headphones is that users tend to wear them for long periods of time and while working out. Higher temperatures and moisture from sweat might speed up the release of harmful substances, Chen and the report authors note.
Gaming headsets in particular stood out for their low marks in the study. That raises concerns about a population that might wear headphones for extended periods, as well as groups like young and pregnant people that are more sensitive to hormone-disrupting chemicals. Compared to an adult, a teen, child, or fetus is more susceptible to the effects of a chemical that might mess with hormones and disrupt how the body develops.
About 60 percent of samples from gaming headphones received a “red” rating for their total evaluation, compared to about a quarter of samples from products that were designed for kids. The higher ratings for many children’s designs show that it’s possible to cut down risks when extra precautions are taken. The report authors are calling on lawmakers to take stronger measures to limit the use of harmful substances in consumer products. That includes banning entire classes of chemicals and requiring disclosures on what kinds of substances are in electronics.
Companies can also get the ball rolling, Brabcová says. “Progressive manufacturers actually give a great signal to the legislation at the end of the day,” she says. Considering that more than 40 percent of the 81 headphones tested ultimately received an overall “green” score, she says brands can certainly meet stricter safety standards. “There are companies who go beyond [legal requirements] and it’s the right of the consumer to choose the brands which have better policy.”