How to fight microplastic pollution with magnets

https://www.bbc.com/future/article/20210825-how-to-fight-microplastic-pollution-with-magnets

by hiddencache • 5 years ago

143 81 5 years ago

Jun8• 5 years ago

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...

chana_masala2• 5 years ago

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?

lend000• 5 years ago

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...

aqme28• 5 years ago

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

skybrian• 5 years ago

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.)

pibechorro• 5 years ago

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!

hinkley7• 5 years ago

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.

nazgul17• 5 years ago

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?

foerbert• 5 years ago

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

jiveturkey• 5 years ago

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".

ayemiller• 5 years ago

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

Tildey• 5 years ago

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.

infogulch• 5 years ago

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

selcuka• 5 years ago

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...

MomoXenosaga• 5 years ago

Plastic doesn't decay it just gets smaller.

maxerickson• 5 years ago

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.

hypertele-Xii2• 5 years ago

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.)

notanzaiiswear2• 5 years ago

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.

beervirus2• 5 years ago

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.

chana_masala2• 5 years ago

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

jazzyjackson• 5 years ago

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.

eurasiantiger3• 5 years ago

There is an entire society devoted to researching this area.

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

irjustin3• 5 years ago

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

DoingIsLearning3• 5 years ago

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...

morpheos137• 5 years ago

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

formerly_proven3• 5 years ago

^ 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.

mediaguilt• 5 years ago

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…

flovec• 5 years ago

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.

01100011• 5 years ago

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.

strainer• 5 years ago

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.

formerly_proven3• 5 years ago

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.

beervirus2• 5 years ago

So, no evidence then?

gizmondo• 5 years ago

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

Do you per chance also advocate against 5G?

eurasiantiger3• 5 years ago

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

Ice_cream_suit• 5 years ago

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

moring• 5 years ago

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

MauranKilom• 5 years ago

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

hinkley7• 5 years ago

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

regularfry• 5 years ago

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?

api• 5 years ago

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.”

giarc2• 5 years ago

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.

azeirah• 5 years ago

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)

hmm320• 5 years ago

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

irjustin3• 5 years ago

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/...

PKop• 5 years ago

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

hinkley7• 5 years ago

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.

How to fight microplastic pollution with magnets

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