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Comment by unhashable | Hacker News Reader

Avoid plastics. Any move away from BPA is merely rebranding.

https://www.scientificamerican.com/article/bpa-free-plastic-...

And if you have no other (good) options, compromise by avoiding abuse (mechanical, heat, UV, harsh chemicals, acidic foods, dishwasher) and retiring the plastic early, 2-3 years.

Also, while all plastics leech, HDPE/LDPE & PP appear to be the best choices if you're concerned about this. BPA, BPS, etc are added to polycarbonate.

(In classic fashion, HDPE/LDPE & PP are the most boring of plastics)

The article you linked is specifically about BPS. The article that you are commenting about is about TMBPF and how the move to TMBPF is not just rebranding but an rather transparent search for a plastic that works and is safe.

I like the idea of avoiding plastic as possible, but saying "any move away from BPA is merely rebranding" is wrong and not helpful. This sort of alarmist comment is more likely to move people away from your point of view or at least give them incorrect ideas.

> TMBPF had another apparent advantage. Manufacturers use two chemical steps to forge BPA into can linings. In the second stage, some BPA molecules don’t get incorporated into the polymer chains. Those strays are thought to account for most of the BPA that leaches from linings. Valspar chemists found a way to use TMBPF just once, early in the process, stanching the release of the unlinked molecules.

The article is, at least somewhat, about their tetramethyl bisphenol F compound having a process advantage to bisphenol A which could reduce the leeching.

I wonder if there are any alternatives for sports drink bottles. Glass and metal bottles sound safest but you can't compress them to easily drink single handed.

Handle?

Apparently silicone ones exist:

https://www.amazon.ca/Collapsible-Silicone-Water-Bottles-Cam...

Does silicone not leach? Isn't it a synthetic compound as well?

Is also be concerned about residual chemicals from the manufacturing process, and this goes for metal too. For example I'm sure the molds have release spray that can get passed into the bottle, same with stainless steel machine spray, oils, and greases. And the thing with metal containers is that it's slightly porous and the chemicals can permeate a bit which would then leach back into the water. Another concern is low grade recycled metals with previous chemical contact used to manufacture the bottles of produced in places like China.

silicone doesn't require mold release on a nicely machined mold. If it IS required, such as with complex shapes, food-grade oils are used.

I suppose you could get a newly machined mold that may have cutting oil or something impregnated in the metal, but i'm not sure how you'd avoid that anywhere ,really.

(Just wash everything thoroughly when you receive it and buy from reputable dealers, that seems about as good as you can get.)

food-grade oils should be* used

And yes, I agree it's something that's a concern with everything and I hate that I can't ignore it and it's always at the back of my mind. I used to work in FDA related manufacturing and I know how things operate.

https://en.m.wikipedia.org/wiki/Silicone

Silicones exhibit many useful characteristics, including:[1]

>Low thermal conductivity

>Low chemical reactivity

>Low toxicity

>Thermal stability (constancy of properties over a wide temperature range of −100 to 250 °C).

>The ability to repel water and form watertight seals. Does not stick to many substrates, but adheres very well to others, e.g. glass.

>Does not support microbiological growth.

>Resistance to oxygen, ozone, and ultraviolet (UV) light. This property has led to widespread use of silicones in the construction industry (e.g. coatings, fire protection, glazing seals) and the automotive industry (external gaskets, external trim).

Never mind sport drinks, what about water? All sold in plastic bottles.

Tap water? There are filtration systems for those living where the tap water is not drinkable.

Good mineral water is bottled in glass (and has beneficial minerals).

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