"These chemicals are not just additives; they may be migrating from the headphones into our body," said Karolina Brabcová, chemical expert at Arnika. "Daily use—especially during exercise when heat and sweat are present—accelerates this migration directly to the skin. Although there is no immediate health risk, long-term exposures, especially vulnerable groups like teenagers, are of great concern. There is no 'safe' level for endocrine disruptors that mimic our natural hormones."
> There is no 'safe' level for endocrine disruptors that mimic our natural hormones
Can someone knowledgeable comment on this? It seems extreme to say there's no safe level.
There's a safe amount of cyanide (apple seeds), radiation (everywhere), safe speed of a bullet flying at you (if I just throw it gently at you) and so on. Even if the cyanide is technically poisoning you, the radiation from bananas is damaging you and the bullet I threw lightly grazed your skin, it's still safe in practical terms.
The lowest concentration of BPA that's been shown to be estrogenic according the second article is 0.1pMol/L which is around 230 picograms per litre of blood, or 1.1ng total for an average adult.
BPA's biological half life in humans is up to two to five hours depending on a range of factors (https://pmc.ncbi.nlm.nih.gov/articles/PMC2685842/), so taking the worst case you'd need to be continually exposed to around 2.5ng of BPA over a day.
So 'safe' as defined right now would be keeping the absorption below that 2.5ng per day threshold.
I don't know how how much BPA in plastics can transfer out per day, the research I've seen seems to indicate that unless it's a food container it's pretty minimal but I don't know enough to evaluate the quality of that research.
Your skin is also a pretty good barrier so only around 2.2% of any BPA on your skin can pass through in an ideal situation, so absorption from non-food sources is much lower (https://pmc.ncbi.nlm.nih.gov/articles/PMC9210257/)
The other problem is what do they replace BPA with? To be safer it would need at least as well studied as BPA, but often it seems like the 'safer' options are just not very well studied yet and could actually be worse.
> research I've seen seems to indicate that unless it's a food container it's pretty minimal
I use glass jars for storing food. One of the reasons is stuff like BPA leaching from the plastic to the food. Another is that it's much easier to have hundreds of identical jars to have a pretty and consistently filled kitchen cabinets. A third is that transparent plastic becomes less transparent after multiple washes with a sponge.
But what I hit "reply" for was to say that heating plays a role. So putting hot food inside a container is likely worse than putting something at room temperature in a container and then putting it in the fridge.
> 1.1 ng total for an average adult
Wow, that's so little. I wonder if malicious BPA poisoning cases have been reported. It's probably undetectable unless you search for it specifically.
> The other problem is what do they replace BPA with?
I remember reading that BPA could be replaced with BPB. Obviously it may be OK, but to a layman it's like saying "we no longer add rat shit to our food, now it's bat shit".
1.1ng is a very small amount, but the effect is really not that well understood. It’s definitely something we should minimise.
However it’s not a dangerous dose, it’s just the dose that produces detectable changes and we can detect really really small changes. The toxic dose is around 4g/kg body weight. So an average adult would need to consume over 300 grams of pure BPA to be poisoned by it.
Of course the answer is to use non-plastic containers, though the most common plastic used for food (PET - milk bottles, most soft drinks etc) don’t contain any BPA. It’s the reusable ones that do.
I have glass containers for food, though I do still use plastic ones for short term storage for things I won’t heat. Honestly this seems like the best answer, metal, wood and glass if you can.
For things you put on your skin that could be absorbed, shouldn't the limit take into account the area touching your skin? If I lay on a bed containing 10 mg/kg BPA, I would absorb a lot more than if I touch a headphone. So maybe it should be mg/kg*m^2 or something?
The article is actually IMHO overly conservative. This kind of migration is not a theoretical risk, but well established. BPA is a small molecule, not covalently bound to the plastic. It absolutely goes into the skin. Heat, water, and acidity (sweat is slightly acidic) all accelerate the absorption.
Plus absorption through the skin is worse than oral. Because when you eat it your liver breaks a lot of it down. When it goes in the skin it bypasses all that.
Good point. And diving in I realize my fear was mostly unfounded. Compared to typical background exposure (what we can infer people are getting through other sources by looking at their urine) this is insignificant, except for the very worst headphones. The headline is unsurprisingly alarmist, because by their own data 68% have acceptably very low bpa. But the very few with the worst amounts drag up the arithmetic average to something scary sounding.
To estimate how much gets into the body
https://oehha.ca.gov/sites/default/files/media/downloads/crn...
Is a good reference. Interpolating from that, a typical pair of in-ear buds works out to something like a fraction of a nanogram per kg bodyweight per day, versus 30–130 ng/kg/day from background. So totally negligible. Even the worst case - highest measured concentration, assuming over ear headphones (much more contact area), and a hot sweaty workout, you’re looking at maybe 5ng/kg/day - still in the range of dietary background, but not good.
Because the em-dashes? In a professionally typeset article, the presence of em-dashes isn't really suspicious because that's how they're supposed to be used. AI learned to use em-dashes somehow, it's not like they invented the concept.
The Guardian printed the same quote without em-dashes, and with spaces around hyphens instead. https://www.theguardian.com/technology/2026/feb/18/hazardous... And in the next paragraph of the Arnika article, they have em-dashes surrounded by spaces, in contrast to the quotation which doesn't leave any space around them. It's not clear where the style choices were made in the quote.
Counterpoint: these patches are used specifically for slow, controlled absorption of the medication in order to provide symptom relief over long durations. And even then, many drug patches use microneedles to overcome the skin's natural defense against absorption. Only the smallest of molecules can naturally pass through unbroken skin, and the fact that absorption is slow is the primary benefit of medicinal skin patches. They're used for things like hormonal therapeutic treatment or nicotine replacement because for those use cases, the slow, controlled absorption rate is beneficial for long-term relief.
