4 ms·
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 covalentl
by oofbey 7mo ago
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.
- amelius 7mo agoBut are the quantities significant?
- oofbey 7mo agoGood 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/crnr/tvcbpasudsupportingmaterials041720.pdf 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.