A plastic once thought harmless may be fueling fatty liver disease | Hacker News Reader

A plastic once thought harmless may be fueling fatty liver disease

sciencedaily.com

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Wow, that was hard to read. I'm not usually a big micro-plastics guy, but when I am, I read the primary sources.

https://www.science.org/doi/10.1126/sciadv.aec8681

I'd be so curious for them to test high- and low-density polyethylene.

This is a great question to ask. If you look at the GRAS list, some molecular weights of PEG are GRAS while others are not. There’s no reason to think other polymers should be different.

GRAS is “Generally Recognized As Safe”: so for example you don’t need to do a study on its safety when using it in a drug formulation.

Yeah HDPE is/was generally recognized as safe.

In America, most milk comes in HDPE jugs unless you opt for the glass bottles (much more expensive), or paper cartons (PFAS lining concerns).

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

So one would hope HDPE is still GRAS (i.e. there should be a focused study on LD/HD PE).

FWIW I could not find it in the SCOGS database. I don’t know what the food packaging rules are (I only worked on the pharma side)

Thanks for looking into it!

What was hard about it?

I have no clue why we considered plastic so harmless when it simply wasn't ever possible to do a long term study on things. Now whilst is unrealistic to remove it entirely, it's very easy to reduce plastic use significantly in many areas, especially groceries and toiletries yet we choose not to make that very minor effort.

Because there's no other material with the same properties, at least one that can be made cheap enough and won't fall apart by itself. It's just like oil and gas, we use it because we don't know anything better.

The only way to replace plastic is work hard on making different materials that beat it in every way and scale them up with massive state investment. Then you're fighting multinational companies, neoliberal economists, anti tech green activists, skeptical scientists and corrupt politicians all at the same time.

Sounds so much like the arguments for asbestos.

My personal view is on minimisation, not elimination. Some things practically must* be plastic. Where they don't (like microwave/storage containers, pre-wrapped vs loose item, etc I opt for the plastic-free version.

*economically/practically, not absolutely

I completely agree with you. We use plastic in scenarios where it's just not needed. Bags, packaging for veg and fruit, packaging toys, some toys in general, and so on.

Not everything needs replacing, a significant amount would be fine just by not using. Produce does not need plastic introduced and would be a significant change. Cold drinks in coffee shops do not need plastic cups. Toys don't need to be packaged in plastic and so on.

We have some alternatives that work, and some scenarios where we still need to use it, but we can reduce the use significantly. Like Oil and Gas we absolutely do know better in many scenarios and just choose not to.

Also, so many alternatives to plastics in food packaging are much worse/ cumbersome hygienically so the long term benefits will cancel out because of more acute food poisonings

You don't need better materials, we already have those materials like paper and glass and foils. The only obstacle is they cost a bit more to use. Obviously it isn't an infeasible cost though because we did it 100+ years ago when all those materials cost even more.

What does this mean for Pex and other plastic water mains?

I was going to say, get a reverse osmosis filter, but then I looked up what themembranes are made of: polyamide. Not sure if that's an implicated type of plastic or not.

Good question. We built a house 25 years ago and insisted on copper throughout all the way to the street. Cost more, but was probably a good idea on multiple fronts.

Lead soldered joints?

Lead solder was banned for plumbing in the US in 1986.

Even if they used leaded solder, in the conditions that would cause lead leeching you would also be corroding the copper pipes within a few years to leaking so it wouldn't last too long.

That's why Flint's water system had to be almost completely replaced. Even fixing the pH problem wasn't enough because they turned their pipes into swiss cheese.

You’re basing your belief on one anecdote?

I thought about doing this but then realized that there is basically zero chance there is copper all the way to my house, so yeah, I gave up.

I actually saw the plumber dig up the mains that ran to my place and it was pex.

Do you mean from the mains to the water meter or from the water meter to the house? We used copper all the way to the street.

I can’t believe the mains themselves could use PEX: if nothing else the pressure would be too high.

They meant HDPE but assumed it was PEX, which it isn’t. PEX is cross linked polyethylene and used for mostly indoor piping, and HDPE is high density polyethylene. Common mistake.

HDPE is used extensively in all underground utilities, including but not limited to water, sewer, gas, electric, fiber.

Ok but it's plastic, and not cooper ?

In mice. May be.

great

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