Researchers use electron beams to eradicate forever chemicals in water(phys.org)
phys.org
Researchers use electron beams to eradicate forever chemicals in water
https://phys.org/news/2024-02-electron-eradicate-chemicals.html
93 comments
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.
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.
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.
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_commercial...
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_commercial...
It only takes one successful attempt, and it's worth it
Don’t put heavy metals in roads. Roads are continuously broken down by traffic and freeze/thaw cycles. The dust from this process then gets carried into rivers and streams by rain as stormwater runoff.
People previously had the idea of using ground up post-consumer plastic pellets as filler in roads. Now that stuff is finding its way into the waterways by the above process.
People previously had the idea of using ground up post-consumer plastic pellets as filler in roads. Now that stuff is finding its way into the waterways by the above process.
Well. In Florida, they plan to put radioactive waste in the roads. Checkmate.
Wait what? Lol
"Florida is another step closer to paving its roads with phosphogypsum — a radioactive waste material from the fertilizer industry — after Gov. Ron DeSantis signed a controversial bill into law Thursday. ...The [Environmental Protection Agency] regulates phosphogypsum, and any plan to use it in roads would require a review."
https://www.npr.org/2023/06/30/1185280180/florida-roads-radi...
https://www.npr.org/2023/06/30/1185280180/florida-roads-radi...
It's bizarre to me that the EPA says (linked in that article) it's permitted to put this in food, but not in roads.
- "Since there are large quantities of phosphogypsum waste, the industry encourages research into potential uses in order to minimize the disposal problem. The greatest use of phosphogypsum is in agricultural applications. Researchers proposing new uses must file an application with EPA."
- "Phosphogypsum has been used in agriculture as a source of calcium and sulfur for soils that are deficient in these elements. When the phosphogypsum is used as a fertilizer, it is simply spread on the top of the soil. When used for pH adjustment or sediment control, it is tilled into the soil."
- "The activity of phosphogypsum used for agricultural purposes may not exceed 0.37 Bq/g (10 pCi/g). An estimated 221,000 MT of phosphogypsum are taken from the phosphogypsum stacks and used in agriculture each year. There is no limitation on the amount of material that can be applied and farmers do not have to maintain certificates or application records."
- "In the past, phosphogypsum was incorporated into a Portland cement mixture for use in road construction. The use of phosphogypsum for such purposes is banned under the EPA final rule issued on June 3, 1992, which amends 40 CFR 61 Subpart R."
https://www.epa.gov/radiation/tenorm-fertilizer-and-fertiliz...
- "Since there are large quantities of phosphogypsum waste, the industry encourages research into potential uses in order to minimize the disposal problem. The greatest use of phosphogypsum is in agricultural applications. Researchers proposing new uses must file an application with EPA."
- "Phosphogypsum has been used in agriculture as a source of calcium and sulfur for soils that are deficient in these elements. When the phosphogypsum is used as a fertilizer, it is simply spread on the top of the soil. When used for pH adjustment or sediment control, it is tilled into the soil."
- "The activity of phosphogypsum used for agricultural purposes may not exceed 0.37 Bq/g (10 pCi/g). An estimated 221,000 MT of phosphogypsum are taken from the phosphogypsum stacks and used in agriculture each year. There is no limitation on the amount of material that can be applied and farmers do not have to maintain certificates or application records."
- "In the past, phosphogypsum was incorporated into a Portland cement mixture for use in road construction. The use of phosphogypsum for such purposes is banned under the EPA final rule issued on June 3, 1992, which amends 40 CFR 61 Subpart R."
https://www.epa.gov/radiation/tenorm-fertilizer-and-fertiliz...
Quite a bit of phosphate ore is naturally contaminated with Uranium which of course winds up in the soil and then food. Uranium is notorious for being radioactive but it is also toxic in the same way as lead and mercury with a toxicity per pound intermediate between the two. Potentially this is an energy resource
https://world-nuclear.org/information-library/nuclear-fuel-c...
https://world-nuclear.org/information-library/nuclear-fuel-c...
Some things are safe enough to eat but not safe to breathe aerosolized.
For example, pure elemental mercury.
For example, pure elemental mercury.
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https://www.space.com/air-pollution-reentering-space-junk-de... immediately made me think of where all burn up space ‘junk’ goes.
> Sensitive sensors in the nosecones of the planes analyzed the chemical compounds diluted in the thin, pristine stratospheric air, which is out of reach of Earth-based air pollution sources. The researchers found traces of lithium, aluminum, copper and lead in the sampled air. The detected concentrations of these compounds were much higher than what could be caused by natural sources, such as the evaporation of cosmic dust and meteorites upon their encounter with the atmosphere. In fact, the concentrations of these pollutants reflected the ratio of chemical compounds present in alloys used in satellite manufacturing, the researchers said in a statement.
> Sensitive sensors in the nosecones of the planes analyzed the chemical compounds diluted in the thin, pristine stratospheric air, which is out of reach of Earth-based air pollution sources. The researchers found traces of lithium, aluminum, copper and lead in the sampled air. The detected concentrations of these compounds were much higher than what could be caused by natural sources, such as the evaporation of cosmic dust and meteorites upon their encounter with the atmosphere. In fact, the concentrations of these pollutants reflected the ratio of chemical compounds present in alloys used in satellite manufacturing, the researchers said in a statement.
So.. "fight fire with fire".
"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?
...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?
“ 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.
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.
>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.
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.
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.
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.
> 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.
The interest rate is the mediator between the short term and the long term. Lower interest rates mean that the long term is comparatively more important.
The interest rate is the mediator between the short term and the long term. Lower interest rates mean that the long term is comparatively more important.
I don't think they're doing any cleanup in the first place, so they can't save money by skimping.
Why? As long as the fine is a fraction of the profits, it's just the cost of doing business.
Huh? You could say that about any cost at all. Yet, companies are constantly on the look out for ways of cutting costs. Use less material, use less labour, pay lower fines, find a way to optimize taxes, etc.
> 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
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
How would they profit from falsifying lab reports on research into methods for remediation of pfas contamination?
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.
The next round of flogging and lawsuits will come long after most of the people involved are gone, having already received their accolades and bonuses for "solving" the problem.
Incentives for a corporation are not the same as the incentives for the people, and the corporation's decisions are made by people who follow their own incentives.
Incentives for a corporation are not the same as the incentives for the people, and the corporation's decisions are made by people who follow their own incentives.
Yes, but it's the job of people who have fiduciary duties to the shareholders to design the incentives in such a way that they align.
That's eg why top executives get so many shares (or call options on shares).
That's eg why top executives get so many shares (or call options on shares).
This same duty was there already for decades and it didn’t prevent them from destroying the environment. I don’t think it’s the gotcha argument you think it is. In the end their growth was bigger than any lawsuit.
What's a "gotcha argument"?
If the growth was bigger than the lawsuit, then from the corporations point of view, the earlier executives made the right decisions.
We were talking about aligning interests of executives and long term shareholders. You seem to be talking about aligning interests of those shareholders and interests of the environment or so?
That's an important topic, too, but it's not the same.
If the growth was bigger than the lawsuit, then from the corporations point of view, the earlier executives made the right decisions.
We were talking about aligning interests of executives and long term shareholders. You seem to be talking about aligning interests of those shareholders and interests of the environment or so?
That's an important topic, too, but it's not the same.
Yeah, it's their job. What's your point? Are they actually doing it? Signs point to no.
But maybe the real problem is that most of today's shareholders will be gone by then, too. They benefit from juicing the stock and selling high, leaving the cost for some other sucker down the road. They have no incentive to find uncomfortable truths either. I think short-term ownership is one of the roots of a lot of today's economic ills.
But maybe the real problem is that most of today's shareholders will be gone by then, too. They benefit from juicing the stock and selling high, leaving the cost for some other sucker down the road. They have no incentive to find uncomfortable truths either. I think short-term ownership is one of the roots of a lot of today's economic ills.
> Yeah, it's their job. What's your point? Are they actually doing it? Signs point to no.
The share price today already reflects the long term outlook for the stock.
If you can 'juice' the stock and sell it high, that's a job well done.
> I think short-term ownership is one of the roots of a lot of today's economic ills.
Why? A change in ownership doesn't affect how stock are valuated. If it's eg widely know that a company is going down in five years (because eg their industry is declared illegal), the price will already drop today. It's just a standard backwards induction argument.
Btw, with the stratospheric rise of passive index investing, truly long term ownership has never really been more widespread than today.
The share price today already reflects the long term outlook for the stock.
If you can 'juice' the stock and sell it high, that's a job well done.
> I think short-term ownership is one of the roots of a lot of today's economic ills.
Why? A change in ownership doesn't affect how stock are valuated. If it's eg widely know that a company is going down in five years (because eg their industry is declared illegal), the price will already drop today. It's just a standard backwards induction argument.
Btw, with the stratospheric rise of passive index investing, truly long term ownership has never really been more widespread than today.
And yet, stock prices can swing very rapidly as new info comes out, or as circumstances change. Almost like, despite everyone's best effort, they're at best a very crude approximation of future value.
Current stock prices are our best predictor of future stock prices. You are right that they are still a predictor with a lot of variance.
Stock prices should change as new information comes in, yes. I don't see any contradiction here with what I wrote earlier.
Stock prices should change as new information comes in, yes. I don't see any contradiction here with what I wrote earlier.
You don't see the contradiction with
> The share price today already reflects the long term outlook for the stock.
as an excuse for artificially inflating the stock price? In a context where we're specifically expecting new-but-honestly-predictable information to push it down later?
> The share price today already reflects the long term outlook for the stock.
as an excuse for artificially inflating the stock price? In a context where we're specifically expecting new-but-honestly-predictable information to push it down later?
There can only be predictable news-that-pushes-the-shareprice-lower, if all the people who trade the stock are idiots.
You just need eg a few short-sellers who anticipate those predictable news. They can make a killing by selling the stock at the higher price now and buying it back at the lower price later.
If enough people take this opportunity to make easy money, that brings the share price down today as if the news had already dropped.
So, how do you want to 'artificially' inflate the stock price? Especially how do you want to do it in a way that doesn't require everyone in the market to be idiots only?
You just need eg a few short-sellers who anticipate those predictable news. They can make a killing by selling the stock at the higher price now and buying it back at the lower price later.
If enough people take this opportunity to make easy money, that brings the share price down today as if the news had already dropped.
So, how do you want to 'artificially' inflate the stock price? Especially how do you want to do it in a way that doesn't require everyone in the market to be idiots only?
If this story was true, we would never see large swings in stock price, because they would already be priced in. But we do. Stock price is simply not an accurate enough predictor to create the incentives we want.
(The most obvious reason this is nonsense is that sometimes the future fall is only predictable to people inside the company. Short sellers don't help here. We need another incentive for those people to do the right thing.)
(The most obvious reason this is nonsense is that sometimes the future fall is only predictable to people inside the company. Short sellers don't help here. We need another incentive for those people to do the right thing.)
3M has misled and twisted the truth regarding PFAS before. I trust their word as much as I trust BP's when they come up with excuses for oil spills.
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.
"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.
3M, an entire company built because people couldn't figure out how to cook with butter anymore.
the F in PFAS is for fluorine
if it wasn't in the liquid and wasn't in the air... where did it go?
if it wasn't in the liquid and wasn't in the air... where did it go?
Yeah.
"The fact that we were working with 3M, a world expert in PFAS"
Lol, lmao even. Wonder how they became an expert.
"The fact that we were working with 3M, a world expert in PFAS"
Lol, lmao even. Wonder how they became an expert.
World expert in creating pollution
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.
> 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.
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...
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...
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.
Food packaging on the other hand...... Especially paper straws are really really bad. You should make sure to only use plastic straws.
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.
I avoid it, because I know I'm too stupid to never make a mistake with either a bad scratch, or bad temperature control.
> 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?
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?
Traditional nonstick cookware is just cast iron with plenty of butter (or lard).
When I fry my eggs I add about half a tablespoon of butter to a cast iron skillet. It is nonstick.
When I fry my eggs I add about half a tablespoon of butter to a cast iron skillet. It is nonstick.
I use a cast iron for this purpose
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.
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.
> 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!
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!
I've heard others say the same, but whatever trick there may be to it is 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!
Can confirm.
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.)
Yeah it is a great alternative/addition to cast iron, and can be similarly seasoned.
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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.
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.
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.
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?
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.
> 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.
>Iron deficiency is also problem and for people with a vegetarian, vegan, and women of childbearing age, additional iron may be a good thing.
Cannot remember the source,but iron deficiency is exceedingly rare, while iron overload is common. Anemia which is widely believed to have been caused by iron deficiency is generally a thyroid issue, 'Anemia' goes away if you give iron supplements but so does giving arsenic.
Cannot remember the source,but iron deficiency is exceedingly rare, while iron overload is common. Anemia which is widely believed to have been caused by iron deficiency is generally a thyroid issue, 'Anemia' goes away if you give iron supplements but so does giving arsenic.
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.
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.
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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.
> 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.
I think the iron fish thing was a bust.
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.
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.
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.
> properly seasoned pan
Important operative words in a world where the unknowing are too quick to apply dish detergent, scrub brush, and elbow grease.
Important operative words in a world where the unknowing are too quick to apply dish detergent, scrub brush, and elbow grease.
>I’d be worried about excessive iron intake from a cast iron pan
This is really underappreciated, iron overload is very common.
This is really underappreciated, iron overload is very common.
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.
> 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
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
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.
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.
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.
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
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.
"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?
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?
As sewerage treatment, this would require way too much power.
Look for it in expensive water purifiers for the lifestyle market. Gadget sellers won't have a powerful enough electron beam to do much, because that's both expensive and requires safety systems. But that won't stop them.
Look for it in expensive water purifiers for the lifestyle market. Gadget sellers won't have a powerful enough electron beam to do much, because that's both expensive and requires safety systems. But that won't stop them.
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.
Electron beams are not cost efficient in photolithography. And it is proposed to use electron beams to treat water or garbage?
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.
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.
Ok, big vacuum systems, (you need about 1E-4 torr for an e-beam) are not efficient for garbage treatment. Your comment is a good one; although I thought it was the low throughput that made e-beam photolithography impractical. Ok, so we don’t need nm precision. Still an order of magnitude or more too expensive, I’m guessing. And water treatment…
forever chemicals had one job
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.
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.
to kill everything? all of the other things were just happy accidents
AI and non-living tissue will make the problem "supposedly" go away... :D
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.