Correct! Sorry I did not mean to imply that the glass itself was the problem, just that choosing glass doesn’t mean that the product is phthalate-free. So many foods contain these chemicals because of some contamination during processing.
Glass isn't good enough for extreme non-reactivity, e.g. for containing ultrapure water used in semiconductor fabs. The real gold standard for non-reactive chemicals is PTFE, which is a PFAS. This shows that lumping all PFAS together as "forever chemicals" makes no sense. So long as you never overheat it (easily confirmed with an IR thermometer), PTFE is one of the safest food-contact materials you can get.
Borosilicate glass or soda-lime glass are not good for storing ultrapure water because sodium ions will be leeched from the glass.
This is not something that would matter in any food-contact application.
While PTFE neither is modified by food nor any part of it is leeched into the food, it can retain minute amounts of food in its pores, which may be retained despite further attempts to clean it, which does not happen with glass.
When a PTFE container is used to store different kinds of food, it can transfer the scent of one of them to the other.
The PTFE recipients used for chemical experiments may be cleaned by aggressive methods, e.g. with strong acids and/or strong oxidants, which would destroy any organic substances. Such cleaning methods cannot be applied in a common household.
Therefore borosilicate glass or soda-lime glass are better food-contact materials than PTFE, even if they can react with various chemicals that would have no effect on PTFE, but none of those chemicals are encountered in food.
The association of PTFE with PFAS makes perfect sense. Part of the manufacturing process of Teflon (brand name PTFE) involves (involved?) GenX, which is reactive and was being dumped our drinking water supply.
"Perfluorooctanoic acid (PFOA), also known as C8, is another man-made chemical. It is used in the process of making Teflon and similar chemicals (known as fluorotelomers), although it is burned off during the process and is not present in significant amounts in the final products." [GenX is very similar.]
And there's no technical reason why manufacturing PFAS polymers necessarily has to result in PFAS small molecule pollution. The waste could be captured and treated with processes such as supercritical water oxidation. This would of course cost more, but seeing as there's no good substitute for PFAS polymers, I'd happily pay more for them. Pollution, like all externalities, is a market failure, and it's the government's job to fix market failures with regulation.
Gambling with people’s health for a third time to “correct a market failure” is an incredibly grim proposition. Oh it causes cancer? We’ll try again with a new chemical! New chemical in the water supply? Oopsie, we’ll capture it with this next attempt!
Chemical reactivity isn't the only thing at play here, in fact I'd say it's more burying the lead (kekek) than addressing the issue at hand. Sure glass isn't the most inert material, but another piece of the puzzle that is often neglected is mechanical abrasion. Once that surface has been compromised, the microplastics come right out.
Glass has the benefit of very high chemical inertness while also being extremely resistant to mechanical abrasion. Some types of glass are clearly not good enough (eg most 'crystal'/lead glasses), but borosilicate and fused silica are certainly well proven materials.
Another process that is relevant, leaching, while considered a 'chemical process' does not actually involve any kind of 'reactivity'. It's governed by solubility and statistical mechanics.
The main issue I see is that it's impossible to know how hot a pan surface is, and food cooks very differently at the same temperature depending on things like moisture content. So how on earth do you know whether it's at high temperature?
While PTFE (Teflon) is resistant to many chemicals that would damage borosilicate glass, borosilicate glass is perfectly safe in contact with food.
Borosilicate glass is much more resistant to acids (except hydrogen fluoride) than to alkalis, but most foods are acidic or neutral, none are alkaline.
Of the materials commonly encountered, the safest for food contact are borosilicate glass, normal glass, commercially-pure titanium and stainless steel.
While PTFE is much more inert than common glass and even than borosilicate glass, it is not a good material for food storage.
The reason is that PTFE, like any plastic, is porous, so it can never be perfectly cleaned, but it will retain embedded in it some residues of the food previously stored in it. This can lead just to some undesirable smell, but in appropriate temperature and humidity conditions it can also lead to the growth of bacteria.
For food storage and handling, the best food-contact materials remain glasses or metals, which can be cleaned perfectly.
