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Comment by hospitalJail | Hacker News Reader

The word 'Plastic' needs to die. Instead we should be more specific on the type of plastic.

Teflon, PLA, ABS, resins, foams, etc... are all plastics, but they are so unrelated outside their long chains, its terrible to stereotype them all into one category.

You aren't going to get cancer from PLA or Teflon, but rather the manufacturing process. You can eat these plastics as far as I know and you'd be fine.

Eat something with BPA in it, you are probably going to have a bad time.

Maybe the solution is better labeling. I know its near impossible to have perfect consistency in plastic manufacturing(I worked in foam, mind boggling we consider testing these foams one time, and considered it the same foam for the next 8 years). However, knowing precursors, additives, and potentially process would make a huge difference in our ability to track problems.

EDIT: Someone called out PLA as potentially dangerous. After looking it up, I'm skeptical of the oxygen double bond attached to a carbon attached to an oxygen. The wikipedia article had no health concerns, but that carbon atom seems ripe for reaction. Let me change my answer on PLA to 'I don't know'.

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Maybe the solution is better labeling.

No, we are awash in labels already and I am sick of everything having a legal treatise attached to it. Labels just throw the problem back in the laps of consumers, an approach which clearly does not work.

> No, we are awash in labels already and I am sick of everything having a legal treatise attached to it. Labels just throw the problem back in the laps of consumers, an approach which clearly does not work.

Some labels are good and informative. Some labels are just a way for corporations to blame consumers for what consumers cannot do anything about.

Falsehood: - "Consumers are purchasing toxic products, so that is what we make."

Reality: - "Consumers buy what is available and they can afford."

Recycling labels are some of the biggest falsehoods. Many plastics are simply not recycled at all, I think at best only #1 and #2 plastics are largely ever recycled. Even things like orange juice containers are considered not recyclable due to their heavy plastic coatings inside the paper shell and they will get sorted out to be dumped.

It's one way industry has scammed the public by convincing them much of the waste generated by low-cost (to the manufacturer) packaging was recyclable.

It’s terrible. Plus the west pays the Chinese companies to take care off the plastics anyway. They just dump it in the ocean and nothing is recycled.

Is actually better for the planet that you just burn it yourself instead of wasting diesel on transport to nowhere.

Brand names were introduced to fight product adulteration. We still default to assuming that is working today. We should probably demand that this is actually true.

Like those "WARNING: This product can expose you to [name of chemical], which is known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov." stickers. Fortunately I don't live in California.

It's even worse because it often doesn't include the name of the chemical.

Yes, they're so ubiquitous as to be useless. I don't know what I'm being exposed to or in what concentrations, so most of the time I just ignore them.

Am I being exposed to worrying quantities of lead, or do they sometimes serve coffee in the break room? No way to tell!

The problem is that without labels you're having someone in government decide what risk levels are acceptable to everyone and that simply doesn't work when you have a population that includes upper class suburban mum who is willing to pay for $100 bananas to decrease her lifetime cancer risk by 0.01% and a homeless dude with a $20/week food budget.

And guess which one of these groups has actual influence on government policy? Yup, its the poor who get screwed.

Government regulation often benefits everyone. When a regulation forces all manufacturinng to reach a certain standard, then economies of scale for that drive down the overall price.

If you let consumers decide, what you end up with is upper class suburban mums eating healthy bananas, while the homeless dude eats bananas that were grown in a superfund site.

The main criteria for government regulation is that it appears to benefit the upper middle class who influence government (by being the media, by being organized voters/campaigners and by being the actual senior government people discussing and deciding). Where the regulation is low cost and scales well you get an improvement for the poor too. If scale doesn't apply well (e.g. surgery) or if regulation helps and doesn't harm the upper middle class (e.g. the mountain of regulations around housebuilding in the uk) or if the regulation only appears helpful (e.g. the overregulation of nuclear power) then the poor will suffer (e.g. by dying while on waiting lists or being unable to afford housing or having eye watering electricity bills).

Even if you disagree with my particular examples of the above three classes I think you'll be able to come up with something for each of them.

I see your point though I think you're overstating it. TBH I think the nutrition facts label works reasonably well, and balances sufficiency with market flexibility.

I agree those labels might work, though it'll be tricky to actually find out.

It would transform recycling.

You might not think much about having specific types of labels, but its basically impossible for a chemist to know anything beyond ~8 generic types of plastic in the US.

Target is an example of labels working and allowing consumers to be informed while still taking responsibility at the corporate level.

They have a chemical policy[1] that is moving in the right direction, and labels like Oeko-Tex 100, Oeko-Tex Made in Green, Clean Beauty, BPA Free, Paraben Free and Recycled. The changes they are making as a part of their chemical policy (eliminating PFAS and other concerning chemicals from cleaning and baby items) are benefiting everyone, and consumers who have specific concerns can quickly get more information about what they are buying. Most consumers are increasingly aware of risks, but most do not have the desire or time to look into the manufacturing process for everything they buy.

1. https://corporate.target.com/sustainability-ESG/environment/...

Teflon Aka Polytetrafluoroethylene cookware represents a health hazard. The stuff contains a great deal of Florine and breaks down at 300C, but that’s not purely binary instead it becomes increasingly unstable as your approach the temperature. Further no manufacturing process is perfect, I wouldn’t therefore assume eating significant quantities would be safe.

That said, it’s generally used as a coating rather than a structural element so there’s less of it in the environment.

PS: Toothpaste which you should mostly spit out generally contains less than 0.5% fluoride compounds such as sodium fluoride NaF or tin fluoride SnF2, the F in both being Florine.

Is "Florine" the same as "Flourine", and isn't that what they give children so they get healtheir teeth? I am a bit confused here to be honest.

Edit: Sorry, stupid question, was thinking of Fluoride.

You're thinking of fluoride

Does it contain Fluorine (a dangerous halogen gas) or does it contain Fluoride (the ion of that gas, commonly added to toothpaste and drinking water).

Flourine...

"Fluorine" is also the terminology used for covalently bonded Fl moieties, not just difluorine, the gas.

Fluoride is the ion, but if you want to get pedantic, you're not adding the ion to toothpaste and drinking water - you're adding another fluorine compound which is dissociating in solution.

Ie, when you salt your food, you're not tossing in Cl- ions directly.

I understand that Teflon might be a hazard in pans but feel like it reduces the amount of burned food in contrast to steel/iron pans so much for me that I hope it is a net gain.

(sorry in advance for all who want to suggest iron skillets. I can't make them work in daily use.)

If you are regularly burning food in steel or iron pans, maybe it's time to understand why? I cook in exclusively iron and steel cookware and I cannot remember the last time something got burned (excepting when I deliberately charred something.)

Please don't take your skill in this for granted. It's a gift. I've been using cast iron pans sporadically for four decades, following all of the common advice, and failing magnificently every time. I still use one occasionally to put a crust on a steak ... and then use a small piece of chainmail[1] to defeat the klingons.

It's not that I don't believe you. It just doesn't work that way in my pan on my stove with my food at my skill level, at all. I gave up and buy nonstick pans and replace them every other year or so.

[1] https://www.amazon.com/dp/B0087UYR1S

I don't cook enough (and never steak) for you to assign me much weight, but FWIW I've had a (lighter, spun) cast iron skillet for 8ish years. I followed a seasoning procedure available online that involves (IIRC) 3 rounds of applying thin coats of flaxseed oil and leaving it in an oven at a fairly high temp.

This process went fine, but I always had to baby the pan (had to be very careful cleaning it with said chainmail, very careful with what/how I cooked in it) and had to re-do the initial seasoning several times when it got too troublesome.

This process would leave the pan at a dark brown, and for a while I blamed this on not removing rust well enough before seasoning or not babying it well enough for it to build up to a ~normal black coat.

At some point during the early pandemic I tired of this. I decided to do something similar on the stovetop where I could observe/iterate better. Apply a coat, wait for it to stop smoking, and repeat until it was black. (plus a few for good luck; I didn't keep track; this took maybe dozens of rounds?)

I've had a much better time since then. The most ~babying I've done is applying a few fresh coats if I don't use it for a while or water doesn't bead when I rinse it.

Yeah, when my cast iron skillet starts to act up I'll just lightly scrub it with dish soap and a brillo pad, dry it, then add a very light coating of oil and heat it up on the stove until it smokes. You want some ventilation of course. Then, it's restored to easy fried egg condition.

No oven needed... only some ventilation in kitchen if you cant take it...

Consider a different oil. Flax makes a very pretty but very brittle seasoning. Canola works great IME.

Same. it's an art form sometimes, and i've cooked the same dish and had it come out great... and then the next time get charred like a mofo.

I suspect it has to do with electric vs gas and being able to get and maintain a stable temp with gas. But that could just be a poor craftsman blaming his tools.

I would probably give up on cooking if I had to buy a new set of pans every year. That sounds entirely ridiculous. It's seriously not some special gift to be able to cook on a carbon steel, stainless steel, or cast iron pan. I've even trained people who have never cooked before in a single cooking session. Were they perfect right away? Nope. But it isn't that difficult and learned quickly after a few solo attempts

I cook 99 out of 100 of my meals, and 9 out of 10 meals I cook in a small counter-top air-fryer. The whole gadget costs less than a good pan. That 10th meal is probably eggs in a non-stick pan, so that pan lasts years longer now.

I bought a nice new range right before I discovered the air-fryer, and it now functions mostly as a device for holding up the air-fryer.

I've taught people to juggle or even (barely) ride a unicycle after a lesson or two. That doesn't mean those aren't difficult skills to acquire.

Plus, many people who are learning do not have the privilege of an experienced teacher. Relying on instructions, videos, and trial & error takes more time and energy for most people. I agree with you that it's worth the effort though.

I guess that it is due to the heat source (ceran cook top) and being used to using too little oil (with a teflon pan I use less than a teaspoon in most cases).

I have been learning how to season, cook with, and clean cast iron. As someone who did not grow up using it it’s definitely not intuitive. The other challenge is that I either have to lock it away or teach everyone else in the household how to care for it. At various points in my life I’ve had coatings ruined by roommates, partners, guests, and housekeepers who did things that seemed perfectly sensible like letting it soak in soapy water.

It's similar to how my partner has a stainless steel pan that I avoid using because I have not had the bandwidth to internalize the right ratio of heat, time, and oil to cook things on it without burning/sticking, whereas they have no issue with it. It's a good reminder not to take internalized skill for granted.

Soapy water won't break down the molecularly bonded fat and iron on your cast iron. If you mistake leftover grease for seasoning, then sure, soapy water will get rid of it.

The trick to not sticking on steel pan is just preheating it properly. A drop of water should dance on a properly heated steel pan and things won't stick. Just let it get hot enough.

> Soapy water won't break down the molecularly bonded fat and iron on your cast iron.

In that case I'm not sure what the exact mechanism was. But I know that after others have used/cleaned a seemingly well-seasoned pan I've had to deal with chips, flakes, and/or rust and had to go back through the whole annoying seasoning process. And of course it's entirely possible that despite carefully following instructions that I've done the seasoning wrong -- chemistry is the only class I ever flunked.

> A drop of water should dance on a properly heated steel pan and things won't stick.

My partner made a similar recommendation. It sounds trivially easy but for whatever reason I have not managed to make it work. Given that cast iron (generally) works fine for me I've had minimal motivation to learn the idiosyncrasies of another material, though I would like to give it another shot at some point.

It's gaslighting by the cast iron/stainless steel crowd, pure and simple.

I've talked to multiple experienced and home chefs about this disconnect and they've admitted two things:

1) cooking on a screaming hot pan is possible of course. It's how all professional kitchens work. But it's way harder! You have to pay close attention & the timing for error is very small. Cooking at lower heat on Teflon lets you make more adjustments.

2) After doing everything perfectly, and seasoning perfectly, for the same heat you ABSOLUTELY still need more of some oil or butter on a cast iron or stainless steel then you would for an equivalent Teflon pan. This is non-negotiable.

you can season stainless steel just like you season cast iron, it just requires more coats to hold and will need to be repeated more often. I've seasoned my skillets and frying pans. I'd never bother with my sauce pans bc they get acidic stuff like vinegar for poached eggs, tomato sauce, or fruit, but they're steel anyway so I can just scrub them with wire wool.

This is a bit like saying asbestos may be a hazard in walls but I just can't seem to get the knack for not lighting my house on fire :(

I say that partially as a joke but also it does sort of sound a bit absurd, in the sense that your cooking techniques are just sort of wrong if you are repeatedly burning food to your non-non-stick pan. You need an oil or fat on your pan to provide a buffer or to bathe the food in liquid.

I guess this is the main reason. I am not used to use a lot of fat while preparing food.

Again this might be a balancing act of the negative effects of teflon consumption and consuming too much fat via oil.

You just perfectly illustrated why people keep disagreeing about this.

You can cook a lot of things on a "non stick" telfon pan without an oil or fat.

You can cook far fewer things on a "non stick" cast iron without an oil or fat.

But the cast iron crowd will gaslight the rest of us, and claim that we are just seasoning it wrong but otherwise it is indistinguishable and only superior.

It's like manual transmission.

It becomes more of a fat hazard after this but if you use the proper amount of oil, you can make it impossible to burn food into your pan. lol.

Certainly true. So lets expand the hazard triangle to Fat VS Teflon VS Acrylamide.

There are some great ceramic non-stick pans available these days.

Tried one and failed miserably.

… which are non-stick because they're coated.

Now, I do think some of them are coming coated in silicone-based coatings. The consensus I get asking "are these carcinogenic?" is "probably not?"

But the other problem is determining what a particular pan is coated with: I have not seen a single manufacturer label their pan with anything more informative than that it is coated in "magic science stuff".

300 C is typically the highest setting on a stovetop. I never go above medium when using Teflon cookware. I've not used a cooking thermometer yet, but https://homebli.com/stove-top-temperature-knobs-what-the-num... gives a good general guide line under a section labelled Stove Top Numbers to Degrees.

Also, I only use 'plastic' utensils with the pan. The result, not a single scratch on the pan. The surface looks brand new, I've been using it over a year.

I'd have thought that fluorine, like oxygen, is a strong oxidizer (fluorine being even stronger), and so fluorides, like oxides (e.g. rust) would be extremely stable, among the most stable compounds possible. Unless I'm forgetting the other side: Maybe the other half of the compound is not a strong enough reducer? It's a hydrocarbon though, it burns well in oxygen...

That said, even oxides do break down when heated. Like, that's what smelting is...

Hm...

Carbon Florine bonds are some of the strongest you will find. Carbon tetrafluoride CF4 is almost as safe as nitrogen at room temperature. Tetrafluoroethylene C2F4 is actually explosive on the other hand because of it’s carbon carbon bond, the stuff is happy to spit out the carbon and get CF4.

https://en.wikipedia.org/wiki/Tetrafluoroethylene

Carbon tetrafluoride and Carbon tetrachloride are the two "carbon tets" you never want to mix up.

> Maybe the other half of the compound is not a strong enough reducer?

It's about as strong as most of the molecules on your body.

But I don't think that fluoride moving around is the problem. Looks like the problem is exactly the stability, and some long foreign molecules installing themselves in your body.

> Teflon Aka Polytetrafluoroethylene cookware represents a health hazard.

Are you saying, then, that this claim [1] is false?

It states that PTFE is safe, whereas PFOA — what Teflon used to contain — was the component that made Teflon unsafe.

[1] https://www.webmd.com/food-recipes/is-teflon-coating-safe

PTFE is a PFAS, as is PFOA.

> Now, since PFOA belongs to a large group of chemicals called PFAS, consisting of 4,700 similar substances, it might be tempting to just switch to one of the other PFAS chemicals that hasn’t been restricted yet. But that wouldn´t solve the problem, it would only postpone and perpetuate it. [1]

[1] https://marketplace.chemsec.org/articles/news/2020/04/01/the...

I.e. there's a whole zoo of similar compounds, and all those type specific safety claims are all at room temperature. The whole point of their use is often on heated surfaces, getting near and over the safety limit.

Sorry, but PTFE (polytetrafluoroethylene) may be a PFAS (per-and polyfluoroalkyl substances but not a Perfluorooctane Sulfonate PFOAS) however, it is definitely not a PFOA (perfluorooctanoic acid).

Your link does not contain a reference to PTFE and looking at the meaning of the acronyms should provide evidence fluorethylene is not a sulfonate or an octanoic acid.

The manufacture of PTFE may involve generating these as bio-hazardous byproducts and PTFE could be contaminated or even break down into them, but they are chemically not the same.

I think you misread: GP claimed that PTFE is a type of PFAS, and separately: PFOA is also a type of PFAS. And if PFAS is the problem, it wouldn't be useful to ban specific classes like PFOA if they are just replaced by different classes of PFAS.

I'm not sure about the last claim: it isn't clear that all PFAS are equally bad, so replacing PFOA with a different PFAS might be worthwhile. It seems hard to study, but with Europe banning PFOA, perhaps we'll get some more insight.

Here’s a direct quote from your link: “Health Risks of Teflon Coating

Teflon is generally safe, but heating it to above 300 degrees Celsius or 570 degrees Fahrenheit poses a danger to your health.”

Note they didn’t say Teflon was safe at 299C, the risk is chemical breakdown not a phase transition like water which boils at a specific temperature and pressure. When used properly pans shouldn’t get anywhere close to that temperature range but it’s very possible to get to a dangerous temperature if there isn’t food in the pan.

All the carbohydrates will be coated with Acrylamide or burnt to a crisp. Acrylamide is believed to be a carcinogen (Acrylamide is converted to a compound called glycidamide , which causes mutations in and damage to DNA) and shown to be in animal models.

Once you're frying, roasting, and grilling things at this temperature you are increasing cancer risk completely unrelated to any cooking materials involved. That's true of french-fries, bread, steaks and a zillion other things. It's why they're tasty (see Malliard reaction).

I certainly consider cast iron relatively safe, but it's polymerized unsaturated oil is likely to leach acrylamide and associated chemicals. It's just that compared to the food you're eating it's not relevant.

Hate to be the raving "seed oils are going to kill you" guy, but Acrylamide can be greatly reduced by swapping your vegetable-based cooking oil with something like tallow, lard, or coconut oil: https://pubmed.ncbi.nlm.nih.gov/27374529/

I see online a lot of talk of the temperature and off-gassing relationship. I've also heard that it's slightly misleading because it's temperature and time dependent, where the temperature risk has to occur in such a short period of time that it doesn't reflect cooking use. However, I could not find the off-gassing studies; do you have links? It seems like the temp of 340C most often cited, apparently from a DuPont study.

> When used properly pans shouldn’t get anywhere close to that temperature range

What frying pan when used properly doesn't get near 300 C? A pan surface temp of 200-250 C is nothing strange when frying a steak.

250C is quite a long way from 300C.

It’s the same gap was walking outside into 25f and 115f Aka below freezing to punch you in the face hot.

Heating up Teflon straight up kills birds if they're in the same room.

Source?

https://vcacanada.com/know-your-pet/teflon-polytetrafluoroet...

https://www.teflon.com/en/consumers/teflon-coatings-cookware...

its a thing

> PS: Toothpaste which you should mostly spit out generally contains less than 0.5% fluoride compounds such as sodium fluoride NaF or tin fluoride SnF2, the F in both being Florine.

And table salt is made out of Sodium and Chlorine, one of which is explosive when mixed with water, and the other is used to gas soldiers in trenches if you're into committing war crimes.

What matters is what effect the particular chemical has when you put it through common household uses, not the effect of its constituent parts.

I added that because the first two responses seemed to be confused.

Anyway, uncommon household uses can also be a safety concern. People still do occasionally get poisoned by mixing ammonia and bleach even despite the repeated warnings.

Talking about the constituent parts is similarly relevant when you’re heating something to significant temperatures. Many reasonably safe substances really shouldn’t be tossed on a bond fire etc. For other things it’s not the substance itself that’s a concern but impurities from the manufacturing process. People often think of past recalls as companies doing something dumb, but I think we underestimate how difficult it is to get this stuff right.

I don't want more labels. I don't want to have to be an "informed consumer" when im buying cookware in order to know whats going to give me cancer. Those products shouldn't exist.

Everything has or might have a risk. For all we know carrots increase the risk of cancer.

If we banned everything that increases the risk of some sort of bad thing we'd probably end up banning everything (or more realistically, everything we'd do studies on).

No, the symmetry of "anything could be dangerous" is broken by reality, by what is actually dangerous. Arguments of the form "all things look the same if you ignore all their differences" don't work.

Uh... I think you're assuming all your readers have the same precise understanding of "actually dangerous" that you do.

Is walking "actually dangerous"? Is cycling? Is driving? Is swimming? Is hang gliding? Different people will give different answers to these questions and I've even kept them all to the domain of transportation!

Once you get to the realm of all chemistry things get very murky. E.g. Is sugar dangerous?

In practice we're evolved creatures full of hacks that work well enough to mostly not die before we've had kids, I would be very surprised if there was a single substance we consume (both intentionally and not) that doesn't damage something.

FYI, the labels are not for you. They are for recycling.

"The word 'Plastic' needs to die." ... "its terrible to stereotype them all into one category."

I disagree, because, that's like me telling you "The word 'Cancer' needs to die." etc.

That would imply you'd be required to tell me the specific cancer you refer to when you say "you aren't going to get cancer from PLA or Teflon" etc.

General terms exist for a reason.

Actually I think both cancer and plastics needs to remain as jargon for their respective fields, and instead media should focus on specifying the important elements that are easily digestible to the public and also not too wide reaching. Somewhat of a lost art apparently.

To stay with your example, it would be like discouraging the media from saying "cancer is cured" when they actually might mean "this specific type of lung cancer has a cure". To bring it back to "plastic", the media could focus on saying things like "teflon coating encourages these negative reactions..." as opposed to "plastics are poisoning us" which is way too vague to matter.

> General terms exist for a reason.

And on the case of plastics, that reason is that they are molded by the same processes.

It's about as relevant as talking about "metal contamination" of food when you are measuring mercury.

I'd actually say that cancer as a general term is in fact very unhelpful given the varieties and probably does need to die.

How do you know PLA is safe? I'm sure you would have thought lead was safe at the time

Thank you for bringing this up, I may be incorrect.

I looked at the formula and that Oxygen double bond attached to a carbon with another oxygen bond... yikes!

I have no idea why this is stable. It appears stable, but you wonder about things like UV light, exposure to some cation, etc...

Well, seems like I have reading to do. (Chem engineer here, I feel like its my responsibility, similar to how programmers read open source code)

What does the oxygen double bond bit do? (Automation/controls here and high school organic chemistry was a long time ago, but I've printed kilos and kilos of PLA parts... some parts seem fine after being installed outdoors in full sunlight in a hot environment, they're nonstructural and covered in dust though.)

I'm sorry if this is inaccurate, I'm pulling from orgo 10+ years ago, and I feel like an artist using feelings.

If you look into molecular orbital theory, the double bond causes overlap, which makes the bonds unstable. It can more easily jump off and create a new bond. If you want to see an even worse situation, look at Nitrogen triple bonds.

Further, the extra oxygen attached to the carbon makes the bond a bit polar since you have such a heavy electron clump on one side of the carbon.

I think you’re confusing unstable with energetics it’s certainly unstable to UV but you’d have to look at the kinetics and enthalpies of formation

When neighboring carbons are linked to oxygen, you get a less stable molecule.

That said, yeah, PLA is known to not be very stable, and that's part of the reason its biodegradable. It degrades into lactic-acid based large molecules that living beings have no problem on destroying. (But are toxic when you get several grams of it, so beware if you are doing strange chemical experiments with PLA.)

Prusa has some good info on it. It’s not recommended for outdoor use although I have some outside now doing fine so far (I’m testing PLA vs PETG). https://help.prusa3d.com/article/pla_2062

UV light absolutely destroys it, and PLA isn’t exactly stable. Indoors it seems fine.

That's just an ester bond. That's extremely common in biochemicals, including food.

PLA is just going to break down into lactic acid. Big deal.

PLA - poly(lactic acid) - is biocompatible to the point that it is used in medical implants. It breaks down into lactic acid, which the body produces itself during exercise and can safely metabolize.

Breathing smoke and dust from PLA is bad, because breathing any type of smoke or dust is bad. Wildfire smoke is bad, but wood is not a harmful chemical.

We actually do understand the chemistry of plastics. And to a very large extent they are very safe, primarily because they are incredibly stable and non-degradable.

Even the studies of e.g. BPA health issues point to very weak effects. You need to do meta-analysis on tens of thousands of individuals to have statistically significant effects, and even then they are weak and it's not easy to say whether you have successfully eliminated confounding factors.

And "BPA-free" plastics just use BPF instead, with very similar chemistry. The consumer-facing BPA fuss is primarily driven by companies that want to sell products; health agencies are primarily concerned with occupational exposure, which is 4-5 orders of magnitude larger in terms of dose per body weight. BPA is metabolized in the kidneys to the benign BPA-G and excreted in urine; a dose 250 000 times the EU dose limit is cleared by the body in 24 hours.

PFAS is a similar story. Over long timescales with stupid disregard for basic PPE, like cross country ski waxing trailers where people were breathing C8-dust without masks for a thousand hours per year, there has been clear health concerns identified. So people are saying "there is no safe lower dose limit" and companies are switching to chemicals that haven't been used in the same context so there is little to no data on exposure safety, and saying "this will be safer".

What plasticizers, chain extenders, flame retardants, fillers, stabilizers, colorants, reinforcements, blowing agents, antistatic agents, and lubricants are used with PLA?

I'm not asking to play 'gotcha' with your comment, but because when I've attempted to do my own research on this, I find it easy to get information on the polymer itself, but the polymer is never used by itself in a product. As far as I can tell, most polymers are not actually useful without a cocktail of additional chemicals added to them to change their physical characteristics. From my research, raw polymers tend to be extremely brittle and frangible, completely unrecognizable when compared to the products we use made from them.

And those additional chemicals are extremely difficult to find information on. Like when they're used, what they are, etc.

Oh this is a very good point. Type and amount of additives is very rarely specified, although you can find some info in the academic literature.

As a person completely naive to the finer points of plastics manufacture-do these additives tend to be drawn from a fairly small and well-understood universe of chemicals and combined in predictable ways, or is it a bit more DIY at the level of a specific manufacturing plant or product spec or batch run?

I guess my mind is instinctively reaching for the ways FDA attempts to ensure food safety by compelling manufacturers to publish ingredient lists, and by maintaining registries [0] of hopefully-well-understood additives (and banning the rest, in historically dangerous categories like colorants).

Sure from time to time agitators take that information out of context to whip up a scare about one ingredient or another, and sure some of the food that comes in from overseas has after-the-fact labeling that’s a little sus. But at least there’s an expectation that the information must exist and be legible.

[0] https://www.fda.gov/food/food-ingredients-packaging/determin...

Our skin is a (bio)plastic. It is indeed a completely useless term. Distinguishing between "synthetic" and "non-synthetic" isn't very useful either; all these compounds have in common is that they are toxic carbon-based polymers. It's the fact that they're toxic that is important, not that it's a carbon-based polymer.

Yeah, the problem is definitely that the recycling numbers on plastics aren't detailed enough... /s

Bonus points if you can tell me what each recycling number on plastic means without looking it up (it's the internet, so I have no way to enforce this).

Plastic overuse/overproduction needs to die.

What Microplastics Might Be Doing to Our Intestines https://now.tufts.edu/2023/06/09/what-microplastics-might-be...

Nanoplastic Ingestion Causes Neurological Deficits https://www.the-scientist.com/news-opinion/nanoplastic-inges...

Microplastics can stick in human airways, new study finds https://www.ctvnews.ca/climate-and-environment/microplastics...

Many BPA-Free Plastics Are Toxic. Some Are Worse Than BPA https://www.discovermagazine.com/health/many-bpa-free-plasti...

Plastic pollution is so bad for animals it now has a disease name — 'plasticosis' https://www.cbc.ca/radio/quirks/research-ocean-plastic-birds...

Microplastics found in every sample of water taken during the Ocean Race https://www.theguardian.com/environment/2023/jun/05/micropla...

Secret industry documents reveal that makers of PFAS 'forever chemicals' covered up their health dangers https://phys.org/news/2023-05-secret-industry-documents-reve...

Forever Toxic: The science on health threats from plastic recycling https://www.greenpeace.org/usa/reports/forever-toxic/

Microplastics detected in meat, milk and blood of farm animals https://www.theguardian.com/environment/2022/jul/08/micropla...

Yet Another Problem With Recycling: It Spews Microplastics https://www.wired.com/story/yet-another-problem-with-recycli...

Tiny Polystyrene Particles Detected in the Brain Just Two Hours After Ingestion https://neurosciencenews.com/polystyrene-brain-23079/

60% of home ‘compostable’ plastic doesn’t fully break down, ending up in our soil https://blog.frontiersin.org/2022/11/03/60-of-home-compostab...

(... thousands others)

We refer to them as plastics because it's meaningful and useful to do so in most contexts, including the context of the harm they do. Whether that harm is done during manufacturing or ingestion is irrelevant. They're all plastics and they all cause harm.

It's not useful to nitpick over their long chains or oxygen double bonds. That rhetoric contributes nothing but deflective nerdery and confusion to the conversation.

As we become more interested in the relatively new information about these materials, different kinds of conversations are occurring than we've had in the past. To facilitate these new interests, it's entirely possible that some of the more specific terms could/should/will become part of the household or water-cooler vernacular. BPA already has.

> deflective nerdery

FWIW, the point about carbon bonds was actually a response to nerdery that's already present here, in a forum intended for digging into the nerdy details of various subjects.

"Plastic" is not actually a useful or meaningful term. E.g. if scientists made perfect artificial skin that was atom for atom identical to your skin it would be mostly made of plastic.

Not all "plastics" cause harm (at least, not any more than the skin you shed every day).

If you go up to someone in the street, and tell them about the plastic in the water supply and food they eat, how it's harming them, and that we need to better clean it up and regulate it, they're going to understand exactly what you're talking about, and they won't get into a debate with you about whether you're talking about dead skin, artificial skin, or BPA.

They won't understand, they'll just think they do. Just as if you talked about the dangers of "chemicals" and how dihydrogen monoxide kills thousands of people a year.

I've seen countless disagreements on numerous topics caused by people thinking they both have the same definition of a term and even more instances of confusion because the intuitive implicit definition that came from the example usages they'd seen of a term was a non-representative subset of the things matched by the explicit definition.

Nuance and clarity of language matters, otherwise you'll ban "chemicals" and discover you actually have no sane definition of it and are inflicting a lot of unnecessary suffering.

Ester bonds are not usually dangerous. Wait until you find out what all the natural and synthetic flavorants inside your food are!

As far as polyesters go, the main cause for concern is the endocrine disrupting effect of polyethylene terephthalate[1] and the inability of PET to be broken down completely, leading to microplastic pollution. By contrast, PLA can be broken down by heat or a select number of micro-organisms, and the lactic acid monomer used to produce it is non-toxic. The polymer is formed by a simple condensation reaction to form ester linkages, releasing water. Esters are a very common and generally benign moiety found everywhere in nature, for example in cutin found in plants, forming the rigid exterior of cells exposed to the elements. [2]

[1] https://en.wikipedia.org/wiki/Polyethylene_terephthalate

[2] https://pubmed.ncbi.nlm.nih.gov/11217409/

Many dental flosses are literally strands of ptfe and some studies correlate using them with higher blood concentrations of pfas.

Many “compostable” paper food and drink containers are lined with a ptfe film, which does get into the food.

Okay sure maybe it’s all leftover pfas reagents, (or maybe some break down but ignore that) it’s impossible for anyone to know that this particular instance of ptfe doesn’t have residual pfas.

>skeptical of the oxygen double bond attached to a carbon attached to an oxygen

Ester groups are quite innocuous. The most it will do is hydrolyze to oligomers of lactic acid.

We have this attitude regarding materials which is pretty close to “innocent until proven guilty” but the fact of the matter is that all you can know about any novel material is whether or not it kills you quickly.

I think we either need to appreciate that the industrial world is poisoned and take that as the cost of doing business OR stop poisoning ourselves at the cost of substantial technological progress.

> You can eat these plastics as far as I know and you'd be fine.

Can we? Have these been tested? Alone and/or while interacting with other such things in the wild? Or have these chemicals/plastics been introduced because they can be (i.e., no regulation or oversight), not because they are safe and have been proven to be so.

The default of "they're safe" is not the default we should be using.

I thought bio / water degradation of PLA was seen as a feature.

PLA and other acid co polymers are used in resorbable stitches and polymer medical devices where the biproducts are organic acids and carbon dioxide.

I second the ‘I don’t know’ for actual health effects of PLA but wanted to provide a counter point to comparing PTFE (indestructible C-F bond) to PLA (readily hydrolized C(=O)O- bonds)

I thought the reason people switched to PLA for 3D Printers is that the fumes for it were less toxic than other types of filament. I've never heard of PLA being used for food containers.

PLA has a low melting point. It's gonna end poorly as soon somebody sticks it in the Microwave or puts hot enough food in the container.

A good point. Starches produced by plants are also long chains of sugars. Are they "plastic" too?

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