How to fight microplastic pollution with magnets | Hacker News Reader

How to fight microplastic pollution with magnets

bbc.com

143 pointshiddencache81 comments

The solution proposed uses the fact that oil attracts plastics in water: vegetable oil is mixed with iron oxide to create a ferroliquid, which then attracts plastics and is easy to remove using magnets.

Why does oil attract plastics, though? Because both are non polar. Here's a good r/askscience answer: https://www.reddit.com/r/askscience/comments/meqh0/why_is_oi...

It's an innovative approach, albeit only a partial solution. Unfortunately, not all plastics are polar [0]. And the micro-plastic pollution I see most and feel like I ingest the most of is dust from my own clothing (primarily polyester based, which is somewhat polar). Everyone always says dust is just your skin, but I can see the color of clothes I wear frequently on dust and lint that accumulates in the house.

I also wonder about how many cell membranes would get stuck in the nonpolar layer and if that would have a meaningful impact on local microbiota/algae compared to the amount of plastic absorbed in the process.

[0] http://www.appstate.edu/~clementsjs/journalarticles/zeus_die...

You are correct. The majority of micro plastic pollution to soil and water comes from synthetic clothing.

Cotton, wool, linen, hemp.. we have options people!

Right but...how did you extrapolate from indoor lint to all soil and water? What about all the other non-clothing plastic and rubber noone wants to pay for proper recycling or incineration?

Washing clothes, I would assume.

Washing clothes sends microplastics to the water treatment plant. Notwithstanding leaky sewer systems (and especially combined stormwater systems), that's a centralized problem that can be solved in one spot.

Drying your clothes is a point source problem. Every dryer vent is spewing microplastics into every yard and street. The lint trap only catches the largest fibers.

I heard once from a museum worker that the dust that settles on exhibits is somewhat blue, due to the prevalence of denim jeans.

I’ve seen plenty of blue dust in the cracks of my AirPods case when I put them in my jeans, so I’m not surprised.

When I bought my jeans from H&M, I would sometimes find blue dust on things I kept in my pocket. After switching to a brand that uses higher quality cotton (Nudie Jeans), I have never experienced this.

Durable cotton has longer fibres so that they won’t break off as easily as the short fibred varieties. I guess that is the reason why.

I wish there were (or I knew) a good objective quality metrics for clothing/clothing brands.

It's a skill you can practise. Go to a second hand clothing store and feel the fabrics. Inspect the seams, zippers and what have you. Make mental note of brand labels. You'll develop a sense of quality.

And a second hand store, specifically, because the clothes there being used reinforces the survivorship bias - bad clothes don't make it through recycling.

How to assess the quality of garments (2014) https://news.ycombinator.com/item?id=20503194

https://goodonyou.eco/ seem reasonable.

Price correlates greatly with basic material quality, although platoes quite soon after certain threshold.

I wanted to respond but couldn’t find the words. Then I read in the article [0] linked in a sibling comment:

“ Now, what's important to note is that the quality and the price of an item are not always related. Some types of items are easier to manufacture and get right than others, which is why it is totally possible to find certain well-made items at affordable shops. At the same time, just because an item is very pricey, that sadly does not always mean that the manufacturer used all of that extra money to up the quality of the garment.”

Edit - citing the source [0]: https://anuschkarees.com/blog/2014/05/01/how-to-assess-the-q...

I don't think we're in disagreement. My point was that $50 pair of jeans tends to be better quality than an $10 one, although the difference with an $500 pair is not anywhere as dramatic.

Sure, but the $50 pair might just as well be worse than the $10 pair, they just spent $30/pair more on marketing to convince the buyer they’re something special. Then pocketing $10 more a pair than the cheaper but just-as-good version.

Same with the $500 pair.

It’s just difficult to tell if one can’t evaluate quality oneself.

It may be worse sure, but it more often is better. The 'correlates' part in my reply above.

This from personal experience, or is there a study on it?

Organic cotton has struggled with fiber length, making the big picture view of cotton quite a bit more complicated.

It's gotten better, but I had some early Patagonia organic cotton jeans that basically began to disintegrate. There are some hemp-cotton blends that are fairly soft.

Every time I have to clean the lint out of the power adapter for my iPhone I ask out loud how a company that has been run by two consecutive denim wearers hasn't had to solve the pocket lint problem.

It seems like for dust in the home you'd want to look at the things people might do for allergies, like maybe an air purifier and robot vacuum? (Not to mention dusting.)

Plastics also attract nasty chemicals like aromatic hydrocarbons. To me that's the bigger danger of plastic ingestion. The chemicals intrinsically in the plasting are bad enough, plastic dipped in PCBs or dioxin is horrible. Getting it into the food chain is a disaster.

I wonder then what the other effects of adding oil to the ocean would be. Is there a way to do it that still retains the overall positive effect of removing the plastics?

Adverse effects of the ferroliquid contamination of water ( used to remove microplastics ).

Also: what other, natural particles get filtered out by this method?

Biodegradability of both oil and iron oxide is very different from plastic though.

Are you starting a pool? Can you put me down for $5 on hypoxia?

I am astonished every time I read the average plastic intake of an average person. I never noticed even the tiniest amount of plastic in my water or food. Can someone explain how plastics enter my body undetected by me?

Think about how soft plastic is. How easily a plastic surface can be scratched. How easily it can be chafed. How quickly plastic goggles become opaque from use. How much synthetic lint forms in your belly button from clothes.

Every time a plastic surface is scratched or chafed, or rubs against a rough surface, near invisible plastic dust particles break off and disperse into the environment. You breathe them into your lungs, they settle onto your food and drink and enter your stomach.

Some of them get permanently wedged inside your body. Now imagine a big, unshapely sculpture the size of a chair appears inside your house and you can't get it out for some reason. Sure, your world doesn't end, but it takes up space. How many would have to accumulate until they really started hindering your daily routines? That's what your cells feel like.

Most bubble gum is plastic for fuck's sake. People chew on plastic on a daily basis. (Good news is plastic-free chewing gum have appeared on the market.)

How much of it permanently gets wedged inside of people's bodies, though? It seems to me plastics are not the only non-digestible thing that enters people's bodies, so it seems likely that bodies have a way to deal with it.

The way we deal with other tiny, indigestible items like asbestos and soot is to accumulate them until we die.

Why would it seem likely that our bodies have a way to deal with a man made substance?

A man-made substance whose qualities include a notable resistance to decay microbes.

It's a tiny undigestible thing. There are other such things, for example stones.

You don't ever have that moment when you're drinking from a bottle and you realise you've bitten off the neck of the bottle?

Microplastics are very small. Most likely to be in another thing you're eating (in an organ of an animal for example) than being visible in a sauce or something.

glug glug CRUNCH "whoops I ate the bottle again haha"

The answer here is even in the article title. Microplastics. Nobody is talking about chunks of plastic you can see, or feel, directly.

Microplastics go up to 5mm, by definition. You can definitely see and feel that. And down to 1um! "They" mostly talk about marine life ingestion of microplastics, and both for humans and marine animals I find it very difficult to comprehend what sizes they really mean, given the very large range for the single term "microplastics".

I would say most of it will be dust in the the air (coming from clothing and other textiles) and car tires.

Looking at the study: https://d2ouvy59p0dg6k.cloudfront.net/downloads/plastic_inge... their overall estimate includes 10x the plastic from drinking water that I am likely to be getting from their statements about the water I drink. Drinking water is their #1 contributor.

(I drink US tap water, so ~20 fibers a day, 140 fibers a week, based on that vs 1769 fibers a week based on their stated typical drinking water consumption. There's of course the potential that my water has less fibers than the US average, in which case my consumption of fibers from that source would be lower again.)

So the link is scrubbing the soft language used in the study report "as much as" or "could be" and turning it into an unqualified average globally people ingest an average of 5g of plastic every week.

They are very small [1]. Also you are unlikely to notice, say, a plastic fiber in bread.

https://www.theguardian.com/environment/2019/jun/05/people-e...

Microplastics include any fragment of plastic less than 5mm in length, and nanoplastics (less than 100nm) are much smaller than would be visibly noticeable.

Plastic doesn't decay it just gets smaller.

Is there any credible evidence about harm caused by microplastics? I’ve seen a lot of stuff about how ubiquitous it is, but very little about its actual effects.

Very fair question - It's a mixed bag. Too easy to point to studies that point one way or another.

One study[0] shows that microplastics can cause irritation which could lead to problems. Any underlying condition, this could make it worse. But it's hard to identify conclusive evidence. You'll find pretty equal amount of studies claiming harm vs no-harm, which makes a lot of the whole thing suspect.

Clearly plastics are extremely stable so our bodies breaking them down into the chemical components is basically zero. A lot of the question of microplastics stems around whether or not your body holds onto them long term after ingestion and more importantly if that leads to any significant issues.

Personally, I'm still not concerned. It's not nearly as clear as asbestos in terms of health issues. The risk-reward model of plastics makes me believe it's here to stay for a long time.

[0] https://www.nature.com/articles/s41598-020-64464-9

> The risk-reward model of plastics

Risk for whom, and reward for whom?

You imply that it is the people exposed to the risk that largely benefit when it is mostly a margin/profit reward for companies who continue to externalize the environmental costs of plastic onto everybody else.

Reminder that Coca-Cola alone produces more than 110 _billion_ PET bottles a year, without any responsability for their collection or safe disposal. [0]

Disposal of plastic, should be an operational cost for the likes of Coca-Cola, Nestle, Pepsico, Unilever, Kraft, Mars, etc.

[0] https://www.theguardian.com/environment/2017/oct/02/coca-col...

> You imply that it is the people exposed to the risk that largely benefit when it is mostly a margin/profit reward for companies who continue to externalize the environmental costs of plastic onto everybody else.

That argument would work for plastics that are used internally inside eg Coca-Cola.

But your next example talks about bottles handed out to customers. The benefit here is to those customers.

If eg customers were demanding glass bottles (because of some benefit), and demanding them enough to pay the difference in production costs (including shipping costs etc), Coca-Cola would gladly sell them glass bottles.

In any case, corporations are just legal shells. The real stakeholders are still people. Customers, shareholders, creditors, suppliers, rank-and-file workers and, most important in practice, managers.

> If eg customers were demanding glass bottles (because of some benefit)

Please provide evidence that this is market pull rather than company push? How many convenience stores provide a glass or aluminium alternative? How much advertising is done with PET bottles versus the alternatives?

> and demanding them enough to pay the difference in production costs (including shipping costs etc)

Plastic is cheaper because companies have externalized the cost of waste disposal. The environmental impact of plastic has a cost that current polluting companies are not paying.

> Please provide evidence that this is market pull rather than company push? How many convenience stores provide a glass or aluminium alternative? How much advertising is done with PET bottles versus the alternatives?

Most beer comes in glass bottles. The economics that ostensibly make companies prefer PET over glass are just the same for beer as for soda. The difference is in consumer preferences.

> Plastic is cheaper because companies have externalized the cost of waste disposal. The environmental impact of plastic has a cost that current polluting companies are not paying.

Compare this alternative point of view:

Consumers prefers soda in plastic bottles over the alternatives, because they reap all the benefits, while the cost of waste disposal has been externalized. The environmental impact of plastic has a cost that current polluting customers are not paying.

> Most beer comes in glass bottles. The economics that ostensibly make companies prefer PET over glass are just the same for beer as for soda. The difference is in consumer preferences.

Absolutely false, mass volume beer manufacturers would absolutely love to push for plastic beer bottles. However plastic is actually far more permeable to oxygen than glass and so beer slowly goes flat in plastic bottles, which is why they are forced to use glass. The reason is purely technical and has absolutely nothing to do with consumer preference.

The risk (whether environmental, personal, etc) vs reward (cheap stable containers, easy to mold, easy to handle material) to the individual person will make it stay.

I'm not disagreeing with you. I'm just pointing to the reality that plastics there are so many benefits and it's so entrenched as part of our lives that it's not going anywhere.

Regulation of clean up would be one great solution.

If someone introduced microplastics to your house while you had no part in it - so you find yourself eating and breathing little bits of hydrocarbon chemicals which none of your ancestors in natural history have ever ingested. No mites can digest it, no moulds can compost it, nothing has ever lived with it, its just a new mysterious stuff that you and your children are going to be surrounded by, and get in your lungs and blood and live within from now on ... And you feel fine about it until convinced by science that you shouldnt. Against the advertisements and persuasions of a big industry, how long did it take to establish that cigarette smoke was dangerous? Leaded petrol? AGW? Ay but its probably fine! We can only imagine, chick skeletons full of plastic beads, certain species of sea creatures and microbiota due to perish because they mistake plastic for food, ecologicaly distruptively novel microbiota evolving which may capable of digesting the different kinds of plastic and additives which are alien to life - after billions of years, an alien substance everywhere. No probs, no 'credible evidence' of probs. Carry on then.

The funny thing about tobacco is that it was widely known to be very toxic for hundreds of years before cigarettes were invented. Likewise people realized that leaded petrol (and its fumes) would be toxic, the state and petrol industry disregarded this because leaded petrol was seen as alternativlos.

Science has a fairly decent track record at finding these things. Policy has a fairly shit track record at responding.

Lead paint was banned here in 1929. I think in USA in the seventies?

Yet lead was known to be toxic since ancient times.

As the GP said, science has a good track record of identifying those things.

Yeah, so cigarettes, climate change, endocrine disruptors, soil depletion, dioxines, phosphorus catastrophe.

Ok, I think phosphorous catastrophes were not predicted.

There's a global one ongoing.

Basically phosphorus that has accumulated over a long time is flushed to the seas in a hundred years.

> And you feel fine about it until convinced by science that you shouldnt.

Do you per chance also advocate against 5G?

So, no evidence then?

It would probably not be an issue if it was just plastic. The problem is most plastics contain other chemicals. Many are harmful like BPA or flame retardants. And the these plastics are recycled with their chemicals and made into new plastics and more chemicals, etc…

Unrelated, I would love to hear the reasoning of the folks downvoting your question. Is it because they think you're insinuating that microplastics are just fine(you do not appear to be)? I think most HN readers would appreciate a chance to have a conversation on this and perhaps enlighten some people.

Please folks, use the downvote thoughtfully.

From 2016 - https://science.sciencemag.org/content/351/6277/1039.1.full seems to point to a paywall link https://pubs.acs.org/doi/full/10.1021/acs.est.5b05478

> They show that environmentally relevant microplastic concentrations led to reduced earthworm growth and elevated mortality as compared to a control. Futhermore, earthworms may transport microplastics into soils, from which they may leach into surface waters.

Yes, as one example: disrupts hormones in many animals - including fish and humans.

just to back you up with one citation: "Microplastics Cause Endocrine Disruption and Respiratory Damage in Fish"

https://www.technologynetworks.com/immunology/news/microplas...

Chronic Microfiber Exposure in Adult Japanese Medaka (Oryzias latipes). Lingling Hu, Melissa Chernick, Anna M. Lewis, P. Lee Ferguson and David E. Hinton. PLoS ONE, March 9, 2020. DOI: https://doi.org/10.1371/journal.pone.0229962.

There is an entire society devoted to researching this area.

https://www.endocrine.org/topics/edc/what-edcs-are

No. It is mostly inert dust. Despite the hysteria. Unless you are talking vinyl monomer or something.

^ This is correct. PP and PE account for more than 2/3 of microplastics and are biologically completely inert, which only leaves physical tissue irritation to get an effect (like e.g. the very different Asbestos fibers do). Another 10 % is PET where it is not as easy to tell (because it is a much more complex plastic than PE and PP), however, I have not seen any credible evidence that PET is biologically active (e.g. as an EDC) except for a few bacteria which apparently digest it. As far as I know even the monomers of PET aren't endocrine disrupting, which is overall a rare property in plastics (the monomers of many plastics are pretty nasty stuff and so if the process control is bad, there is a good chance that precursor chemicals end up unbound in the finished plastic).

Overall this means ~80 % or so of microplastics are pretty much what parent says: biologically inert dust.

Except, of course, for the plasticisers within…

Plasticizers are very rarely used for polymers whose name is not PVC.

Here's a video[0] compilation from a worker in an animal feed processing plant where they grind up waste from restaurants and grocery stores, but don't completely remove all the plastic wrapping from the food. So large amounts of plastic gets fed to pigs. Shocking that this is allowed to happen

[0] https://youtu.be/Xp0NSIrbu3Y

If you live in a town that does city composting, you're going to find a lot of vegetable stickers in your 'finished' compost, and it's small enough that it gets through their sifters, so it will probably go through yours too. Some of those stickers are really hard to get off as well, and more of my compostables end up in the garbage bin than I would like.

I really want someone to petition the USDA or FDA or whoever is in charge of this to require that produce be labelled only with biodegradable stickers. I think that would go a long way to answering your concerns as well.

In 100 years we will probably look like we are “terraforming” Earth with atmospheric processors removing CO2 and ocean water filtration plants removing both dissolved CO2 and plastics.

An extraterrestrial visiting might initially wonder if we came from another star. “They seem to be in the final stages of terraforming the third planet and are starting with the fourth.”

Not sure why you are getting downvoted, I think you comment is correct. I think our only way out of this mess is by coming up with technology to reverse our effect on Earth. I've always envisioned a planet where energy is so abundant that we can do things that normally wouldn't make sense, like filter giant volumes of water to remove micro plastics.

Biotechnology already has some answers! There are plastic eating fungi out there, plastic eating bacteria and plastic eating worms (who have plastic-eating bacteria living in their intestines)

These have existed forever but I've never seen any commercial scale application of x eating bacteria.

The article makes a throw-away reference to plastics attracting heavy metals. Does anyone have a feel for whether the same technique would work directly for cleaning up heavy metal contamination, or does it require plastics as a carrier?

I've been wondering about the plastic retainer I wear in my mouth every night. Could it be releasing microplastics?

Late reply but hopefully you'll see this.

No, not in any normal sense. Plastics are extremely stable. Unless you're grinding your retainer down to <5microns, your retainer isn't a source of microplastics.

The pieces we're talking about either need to start small or need to be exposed to some sort of wear system - sun light, waves grinding plastic bottles together that can break down the polymer chain (actually rather hard to do).

The sunlight one[0] acts on timescales of years/decades, which is a problem for ocean and dumps because all those plastic bottles, we're starting to pay the price environmentally.

But personally, no your retainer is not a source you should be concerned with.

[0] https://www.materialstoday.com/polymers-soft-materials/news/...

How about we fight it by forcing Big Beverage to fight it.

Reply on news.ycombinator.com