[HN Gopher] Researchers use electron beams to eradicate forever ...
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Researchers use electron beams to eradicate forever chemicals in
water
Author : PaulHoule
Score : 78 points
Date : 2024-02-22 13:11 UTC (1 days ago)
(HTM) web link (phys.org)
(TXT) w3m dump (phys.org)
| navi0 wrote:
| " Fermilab irradiated these samples with the electron beam and
| shipped them back to 3M.
|
| 3M sampled both the headspace--the air at the top of the
| container--and the liquid to verify that the PFAS of concern had
| been destroyed without releasing hazardous products to the air."
|
| I think this is what we call fox guarding the henhouse. 3M has
| EVERY incentive to declare this whiz bang treatment effective
| because of the legal liability and financial incentives involved.
|
| I'd want independent test results and a full accounting of the
| byproducts of this treatment before putting any faith in it.
| 01HNNWZ0MV43FF wrote:
| Yeah.
|
| "The fact that we were working with 3M, a world expert in PFAS"
|
| Lol, lmao even. Wonder how they became an expert.
| LoganDark wrote:
| World expert in creating pollution
| thfuran wrote:
| >3M has EVERY incentive to declare this whiz bang treatment
| effective because of the legal liability and financial
| incentives involved.
|
| That sounds entirely incorrect. It seems to me that they'd want
| to avoid a second round of public flogging and lawsuits when
| it's later discovered that they falsified efforts to remediate
| their original catastrophe.
| mtlmtlmtlmtl wrote:
| I'm not too sure about that. When profit is the main goal,
| guaranteed savings(not doing the necessary spending to
| actually clean up) in the short term often take priority over
| possible long term avoidance of fines and lawsuits.
|
| In the short term, actually cleaning up and only appearing to
| clean up probably give the same return in terms of PR and so
| on, but the former is cheaper.
|
| Not to say I condone them misleading the public, not at all.
| thfuran wrote:
| I don't think they're doing any cleanup in the first place,
| so they can't save money by skimping.
| 7thaccount wrote:
| Why? As long as the fine is a fraction of the profits, it's
| just the cost of doing business.
| worik wrote:
| > Why? As long as the fine is a fraction of the profits,
| it's just the cost of doing business.
|
| Yes, a problem
|
| Times are changing. It is upto us, but firms are grappling
| with the concept of social license
|
| Clearly in democracies care must be taken not end up in
| endless fights with stakeholders
|
| But even in China the authorities care about social
| attitudes
| thfuran wrote:
| How would they profit from falsifying lab reports on
| research into methods for remediation of pfas
| contamination?
| 7thaccount wrote:
| They say there is a solution to the problem so regulators
| let them pollute more and make more money. Eventually we
| all figure out they lied and it doesn't work or they
| don't use it and then they get a tiny fine. Business as
| usual.
| KennyBlanken wrote:
| It doesn't matter either way. There are multiple problems with
| PFAS - one of which is how toxic it is to the body, and how
| long it stays in the body.
|
| "We can destroy it with electron beams" doesn't mean shit when
| kids are getting a huge dose of PFAS from their happy meal
| french fries.
| LoganDark wrote:
| Those very same french fries may stop containing PFAS
| sometime in the future. However, the kids who loaded up on
| PFAS early in life may never be able to get the stuff out of
| their bodies. :(
| logtempo wrote:
| Maybe we can send kids under electron beam.
| 01HNNWZ0MV43FF wrote:
| No numbers in the summary. How many watt-hours of electricity per
| hundred gallons of water?
|
| > Using nonstick cookware to fry your bacon and eggs can make
| your life easier at that moment, but scientists believe there may
| be long-term consequences because the chemicals used to make it
| nonstick are so difficult to destroy.
|
| I have finally committed to buying cast iron for my new cookware.
| It was difficult because of a stereotype in my brain that cast
| iron == gas stoves == meat. I'm telling myself that cast iron and
| induction stove just means I have lots of money and don't want to
| eat PFAS.
| throwanem wrote:
| I've had far better results with modern ceramic pans than I
| ever did with either Teflon (thin pans = no heat capacity) or
| cast iron whose maintenance is a cast-iron bastard.
| amelius wrote:
| Can confirm.
| worik wrote:
| > cast iron whose maintenance is a cast-iron bastard.
|
| I have had my cast iron fry pan for thirty years
|
| Very easy to maintain
|
| Very tolerant to abuse
|
| As good as the day I bought it
|
| I have heated it to heroic temperatures for cooking meat, on
| the stove top and in the oven. All good, just be *very*
| careful picking it up!
| throwanem wrote:
| I've heard others say the same, but whatever trick there
| may be to it, it's one I've never been able to acquire, and
| not for want of trying. I'm glad cast iron works as well
| for you as ceramic does for me!
| biomcgary wrote:
| I use cast iron almost exclusively (the exception being
| enameled cast iron). Linseed oil (not boiled linseed oil, which
| has toxic additives!) makes for a great low stick surface if
| you are willing to put in the time. Add a thin layer, bake it
| to the smoke point and repeat. Lasts a long time and makes
| cleanup and frying eggs much easier.
| amluto wrote:
| I very consistently get a pretty amber colored sticky surface
| from flaxseed oil. Olive oil doesn't build a film as
| impressively quickly, but the result is less sticky and more
| durable.
| throwway120385 wrote:
| You have to bring it to its smoke point and then wait for
| it to stop smoking. If it's sticky and amber colored it
| means you're not heating the oil for long enough to
| completely degrade it to a polymer coating during
| seasoning.
| worik wrote:
| Use animal fat
|
| Cheap, and better than the best vegetarian oil IMO
| anthk wrote:
| As a Southern European, fat/butter it's a great way to
| clog your arteries.
| dylan604 wrote:
| > cast iron == gas stoves == meat
|
| See, you're equation here is slightly wrong.
|
| cast iron == open fire == food
|
| city folk consider gas stove as open flame, and it cracks us
| rednecks up. sure, you can cook meat in a cast iron, but it's
| much better cooked directly on the grill over the coals that
| were once the open flame cooking all of the sides in the cast
| iron
| alejohausner wrote:
| I'd be worried about excessive iron intake from a cast iron
| pan. Too much dietary iron can cause all sorts of problems. How
| about enameled (glass coated) pans instead?
| shagie wrote:
| I'll note the parent comment:
|
| > It was difficult because of a stereotype in my brain that
| cast iron == gas stoves == meat.
|
| This _suggests_ a diet that is more on the vegetarian side...
| and in _that_ case, cast iron can be helpful as a supplement
| if you _don 't_ have any iron intake from meat.
|
| Food prepared in iron cooking pots as an intervention for
| reducing iron deficiency anaemia in developing countries: a
| systematic review - https://pubmed.ncbi.nlm.nih.gov/12859709/
|
| While I'm having trouble finding it (and thus it may only be
| folklore) - the cast iron skillets used by early American
| pioneers where helpful in supplementing their diet that was
| otherwise low in meats.
|
| https://2012books.lardbucket.org/books/an-introduction-to-
| nu... is one such mention of it:
|
| > Unbeknownst to the American pioneers, the cookware also
| leaches iron, an essential mineral, into foods as they are
| cooked in cast-iron hardware.
|
| > ...
|
| > Dietary sources of iron include red meats, poultry, leafy
| green vegetables, prunes, raisins, egg yolks, lentils,
| oysters, clams, artichokes, and enriched cereal grains. While
| there are many food sources of iron, only a small fraction of
| dietary iron is absorbed. One method of increasing dietary
| intake of iron is cooking foods in an iron skillet. Acidic
| foods high in moisture content, such as tomatoes, absorb more
| iron during cooking than nonacidic foods. For example,
| cooking spaghetti sauce in iron cookware can increase the
| iron content ten-fold. How much iron leaches into food is
| also dependent on cooking times; the longer food is in the
| pan the more iron is absorbed into the food. Stirring food
| more often increases contact time and thus more iron is
| absorbed from the cookware. The utility of iron cookware in
| increasing dietary intake of iron has prompted some
| international public health organizations to distribute iron
| cookware to high-risk populations in developing countries as
| a strategy to reduce the prevalence of iron-deficiency anemia
| worldwide.
|
| ---
|
| So yes, too much dietary iron is a problem. Iron deficiency
| is _also_ problem and for people with a vegetarian, vegan,
| and women of childbearing age, additional iron may be a
| _good_ thing.
| SrslyJosh wrote:
| The idea that you're going to be absorbing a measurable
| amount of extra iron from cooking in cast iron is silly;
| the entire cooking surface is coated in natural polymers
| created with oil/wax during the seasoning process.
| shagie wrote:
| Effect of cooking food in iron-containing cookware on
| increase in blood hemoglobin level and iron content of
| the food: A systematic review -
| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8266402/
|
| > Thirteen researches were found to be suitable for
| inclusion in this systematic review. Four studies
| reported significant increase in blood hemoglobin levels
| while others reported only a minor increase. Significant
| improvement in amount of iron in food and iron
| bioavailability was also observed when food was cooked
| using iron pot or ingots.
|
| https://www.americastestkitchen.com/guides/cook-it-in-
| cast-i...
|
| > The Myth: When you cook in a cast-iron skillet, your
| food will absorb a lot of extra iron so you can
| effectively supplement your diet by using this type of
| pan.
|
| > THE TESTING: We simmered tomato sauce in a stainless-
| steel pan and in seasoned and unseasoned cast-iron pans.
| We then sent samples of each sauce to an independent lab
| to test for the presence of iron. The unseasoned cast
| iron released the most molecules of metal. The sauce from
| this pot contained nearly 10 times as much iron (108
| mg/kg) as the sauce from the seasoned cast-iron pot,
| which contained only a few more milligrams than the sauce
| from the stainless-steel pot.
|
| > THE TAKEAWAY: Since this occurs in pronounced amounts
| only with unseasoned skillets, which you wouldn't use for
| cooking, we don't consider this an issue. A seasoned
| cast-iron skillet will not leach any appreciable amount
| of iron into food cooked in it.
|
| http://www.wsj.com/articles/can-a-pan-add-iron-to-your-
| diet-...
|
| > A 1986 study published in the Journal of the American
| Dietetic Association found that a cast-iron pan used
| daily for a week transferred less iron to certain foods
| than a nearly new pan. The same study found widely
| varying levels of iron transferred to 20 test foods.
|
| > There was hardly any transfer of iron from frying
| potatoes and cooking green beans compared with cooking in
| a glass-ceramic control. But cooking apple sauce in the
| iron skillet added seven milligrams of iron to each
| 3.5-ounce serving. Cooking spaghetti sauce added five
| milligrams. Adult women should consume 18 milligrams of
| iron a day, and men and women over 50 need eight
| milligrams, according to government guidelines.
|
| The referenced study: Iron content of food cooked in iron
| utensils - https://pubmed.ncbi.nlm.nih.gov/3722654/
|
| > Twenty foods were cooked in iron and non-iron utensils.
| Also, three foods were cooked in two iron skillets. Three
| replications were made, and cooking time and pH for each
| food were determined. Duplicate samples of the raw and
| the cooked foods were dried, ashed, and analyzed for
| moisture and iron content. Iron content was determined by
| atomic absorption spectrophotometry. Most of the foods
| (90%) contained significantly more iron when cooked in
| iron utensils than when cooked in non-iron utensils.
| Acidity, moisture content, and cooking time of food
| significantly affected the iron content of food cooked in
| iron utensils. Perhaps because of differing amounts of
| previous use, cooking in different iron skillets resulted
| in some variation in the iron content of food.
|
| ---
|
| Yes, if you've got well seasoned cookware, it's not
| significant (compared to cooking with stainless steel).
|
| However, if it is a regular cast iron cookware that is
| poorly or unseasoned, there can be a significant amount
| of iron leaching into certain foods.
| myself248 wrote:
| If you weigh the pan and figure out how much iron it loses
| over a year, you could compare that to your dietary iron
| intake needs. If it's not over, don't worry about it. If it's
| over, then you have to estimate how much of that iron is
| going down the drain during scrubbing vs how much is going
| into your food.
|
| My gut feeling is that, since cast iron pans seem to last
| quite a long time, they're probably not shedding much iron
| into your food, and the amount of iron the body can handle is
| pretty significant, on the order of tens of milligrams per
| day.
|
| Throw some Wheaties in a blender until they're dust, then
| take a magnet to the resulting pile. If we're not hearing
| about iron toxicity from breakfast cereals, I'm not inclined
| to worry about the pans.
| SrslyJosh wrote:
| The food doesn't even come into contact with the iron.
| There's a layer of natural polymers that coat the inside of
| a properly seasoned pan.
| Arrath wrote:
| > properly seasoned pan
|
| Important operative words in a world where the unknowing
| are too quick to apply dish detergent, scrub brush, and
| elbow grease.
| SrslyJosh wrote:
| Unless you are doing something truly stupid to your cast iron
| cookware, the amount of additional iron in your diet should
| be zero. Please learn about cast iron and the seasoning
| process before spreading FUD.
| artimaeis wrote:
| If you don't want to consume PFAS, you'd be better served
| trying to limit them from food packaging. There's limited
| evidence that cooking with traditional nonstick cookware
| exposes people to PFAS. The evidence shows that discarded
| nonstick cookware exposes the environment to those PFAS. Which
| is awful! But probably not affecting you directly.
|
| Meanwhile, food packaging is unregulated and has been shown to
| be a major source of PFAS. Water bottles are particularly
| guilty.
|
| https://www.consumerreports.org/health/food-contaminants/dan...
| vkou wrote:
| What exactly is 'traditional' nonstick cookware? Teflon?
|
| I avoid it, because I know I'm too stupid to never make a
| mistake with either a bad scratch, or bad temperature
| control.
| oooyay wrote:
| I use a cast iron for this purpose
| mrob wrote:
| Scratching is not a problem from a health point of view (it
| will of course impair the non-stick performance). PTFE is
| extremely unreactive. If you scratch off some and
| accidentally eat it you'll just excrete it unchanged.
| Overheating can be a problem because it can produce
| potentially harmful decomposition products. It's especially
| risky if you cook at high temperatures, e.g. for searing
| meat, or if you use cookwear that doesn't distribute the
| heat well and develops hot spots. I recommend using an IR
| thermometer to learn how you cooking setup behaves. The
| most conservative maximum safe temperature I've seen
| claimed is 200C, and careful and gentle cooking shouldn't
| exceed this.
| ars wrote:
| > or bad temperature control.
|
| In that case you should prefer teflon. Oil with bad
| temperature control is far more harmful, because oil
| produces toxic gasses at a much lower temperature vs
| teflon. You have much greater leeway with teflon to catch
| mistakes, and the results are not as harmful.
|
| And what concern do you have with a scratch?
| ars wrote:
| There is zero PFAS in cookware. It used in the manufacturing,
| but none is left in the final product. And note that Teflon
| itself is not actually a PFAS, but if you google the subject
| many authors pretend that it is.
|
| Food packaging on the other hand...... Especially paper
| straws are really really bad. You should make sure to only
| use plastic straws.
| SrslyJosh wrote:
| You might want to look at carbon steel instead. It has many of
| the desirable properties of cast iron, but it's less brittle
| which allows manufacturers to make pans as thin as ~2mm, which
| makes them much lighter. (They also heat much faster.)
| CastIrony wrote:
| forever chemicals had _one job_
| dylan604 wrote:
| to kill everything? all of the other things were just happy
| accidents
| RIMMRAMMBUS wrote:
| AI and non-living tissue will make the problem "supposedly"
| go away... :D
| shagie wrote:
| To be non-interacting with anything... and that makes them
| rather foreverish.
|
| The problem is that the structure of the PFAS (a fluorocarbon
| chain with an OH at the end) looks a _LOT_ like a hydrocarbon
| chain with an OH on the end... that 's a saturated fatty acid
| which is crucial for body metabolism.
|
| Compare the structure of
| https://en.wikipedia.org/wiki/Myristic_acid and
| https://en.wikipedia.org/wiki/Per-_and_polyfluoroalkyl_subst...
|
| This allows the body to accidentally substitute a PFAS (which
| does nothing) for a fatty acid (which does something - and
| often important things).
|
| https://www.vox.com/2022/8/25/23318667/pfas-forever-chemical...
|
| So yes, it had one job - and it did that job well. It also
| looks like something that has another job... and does that job
| really poorly when substituted.
| philipkglass wrote:
| There are actually a lot of ways to destroy per- and
| polyfluoroalkyl substances (PFAS, colloquially called "forever
| chemicals") before they are released into the environment.
| Incineration, supercritical water oxidation, Fenton chemistry
| variants, even aggressive reducing agents can break these
| chemicals down into low-hazard "mineralized" residue.
|
| The reason they're called "forever" chemicals is because
| _natural_ processes that break these chemicals down are very slow
| acting once the chemicals have escaped into the wider
| environment. Even then, "forever" is a bit of misnomer. Various
| PFAS have environmental half lives on the order of decades,
| comparable to the medium lived fission products in spent nuclear
| fuel. That's not good, but it's not forever; the real "forever"
| pollutants are stable elements like mercury and arsenic.
| PaulHoule wrote:
| I think of this idea
|
| https://en.wikipedia.org/wiki/Plasma_gasification
|
| where the idea is you throw in all your municipal waste and the
| organic material is converted to
|
| https://en.wikipedia.org/wiki/Syngas
|
| which can be burnt to make (much) more electricity than it
| takes to run the torch and heavy metals get immobilized in
| glassy slag that can then be broken down and incorporated into
| building materials such as concrete and roads.
|
| I have this vision though of a civilization that does this for
| 100,000 years and gradually poisons itself the way we did with
| leaded gas.
| nanomonkey wrote:
| I used to work in gasification, and my understanding is that
| Plasma gasification has _not_ reached net positive. You use
| up about as much electricity producing the plasma as you gain
| from burning the syngas in a generator. Normal gasification
| on the other hand, which uses oxygen to do the pyrolysis _is_
| very much net positive. It 's sad to me that this technology
| hasn't taken off, as you can produce a tremendous amount of
| electricity and hot water from waste streams such as
| agricultural waste, woody biomass and trash. Not to mention
| if you bury the biochar it is carbon negative.
| PaulHoule wrote:
| Pyrolysis is one of those things that has a huge literature
| for very little commercial development, a lot like the
| liquid metal fast breeder reactor. It's little remembered
| that people quit burning coal burning power plants in North
| America around the same time they quit building nuclear
| power plants _for the same reason_ which is that it is very
| hard for a steam turbine to compete with a gas turbine.
|
| There is a huge literature on the possibility of gasifying
| coal and burning the gas in a turbine or maybe doing the
| same with biomass, maybe capturing the CO2.
|
| For that matter there are numerous pyrolysis projects aimed
| at converting plastics into liquid fuels, they usually are
| fought bitterly by environmentalists concerned about air
| quality and the fuel being carcinogenic, many of the plants
| have failed to stay in operation because they couldn't
| figure out how to get them running reliably.
|
| Here is a list of mostly failed plasma projects
|
| https://en.wikipedia.org/wiki/Plasma_gasification_commercia
| l...
| ugh123 wrote:
| So.. "fight fire with fire".
| KennyBlanken wrote:
| "It's technically possible to destroy this stuff"
|
| ...that doesn't mean it's relevant to how people are exposed to
| them, that it is economically feasible or practical to do the
| destruction, etc.
|
| It does nothing to address exposure from things like cookie
| wrappers, french fry bags, disposable food trays, bottled water
| (ironically, which some people have to drink because their
| water is contaminated with PFAS.)
|
| The whole point behind fighting against disposable plastics,
| for example, is that despite it being possible to recycle it,
| almost none of it is.
|
| "It has a half-life of up to decades but that's better than
| mercury and arsenic"
|
| Whataboutism? And PFAS have nothing to do with mercury and
| arsenic?
| sandworm101 wrote:
| https://xkcd.com/1217/
|
| Lots of things destroy lots of other things. That doesn't mean
| they are also a reasonable treatment.
|
| >> used an electron beam accelerator at the laboratory for their
| testing.
|
| Yup. I'm sure that most any organic chemical won't last long when
| put in front of an accelerator. Crank the voltage up enough and
| even the water molecules might have issues.
| kokanee wrote:
| I was thinking this too. My favorite fishing lake was recently
| found to have unsafe levels of PFAs. I suspect that if we
| pumped the lake through an electron beam purifier, it wouldn't
| be my favorite fishing lake anymore.
| RIMMRAMMBUS wrote:
| You could start fishing for inorganic items afterwards. All
| it takes is for you to adjust your expectations of what is to
| be your favorite! :D
| delecti wrote:
| That comic really doesn't apply. The "medium" of PFAS (drinking
| water) is a lot less likely to be bothered by hostile treatment
| than the "medium" of cancer cells (our bodies). We're mostly
| not concerned about the water itself, unlike the patient with
| cancer cells in their body.
| amarant wrote:
| "The electron beam is a promising technology to break down PFAS
| in large volumes of water that contain high concentrations of
| PFAS,"
|
| I wonder how well this works with water that has low
| concentrations of PFAS, because I guess that's what we've really
| got.
|
| Also, would be nice to have some numbers on power consumption per
| cubic meter of water treated: is it feasible to deploy this
| method in waste water treatment plants for example?
| aj7 wrote:
| Electron beams are not cost efficient in photolithography. And it
| is proposed to use electron beams to treat water or garbage?
| nomel wrote:
| This is like comparing the price of a sewing needle to a needle
| in an atomic force microscope. The beam is not what's
| expensive. It's the requirements set by what you're using the
| beam for.
|
| For photolithography you're steering the beams with such
| precision that it results in one of the most accurate
| manufacturing processes known to man, in vacuum chambers,
| performed in cleanrooms, involving purities in the tens of part
| per billion for the materials involved.
|
| That sort of accuracy isn't required when blasting garbage.
| Electron beams are how old CRT TV's worked, which were in
| nearly every home. If you have access to a vacuum chamber, you
| could order the parts off Amazon, if you want to DIY. You can
| also just go buy an electron beam welder and be done with it.
| khaki54 wrote:
| Ok phys.org let's not pretend that most of the PFAS contamination
| came from firefighting efforts rather than just dumping it into
| the ground or water.
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