Harvesting metal from plants that suck it out of the ground

It depends a lot on how the plant is uptaking the metals. If it draws in the metal directly through the roots, then yes. But if instead the metals are drawn to the plant through the microbial network in the soil then metals can be removed far deeper and wider than the actual reach of the roots.


They’re already involved.


Another nice article from last year:


Would the extraction of bog iron from iron bacteria, common in Iron Age Europe, be an early example of phytomining?

The article also notes:

Bog iron, like other hydrous iron oxides, has a specific affinity for heavy metals.[1] This affinity combined with the porous structure and high specific surface area of bog iron make it a good natural sorbent.[2] These properties combined with the fact that bog iron is cheap to obtain are incentives for its utilization in environmental protection technologies


I suspect if the end result is less toxic metals in the soil, less destructive mining techniques and increased green cover, the end results should not be terribly different with either endeavor. I am not sure about the viability of this to satisfy the seemingly endless hunger for metals in our society, but anything that decreases surface mining would be a net gain. OTOH, not my area of expertise, and I defer to those who know far more than I.


It’s more the long term consequences. If phytomining has little to no negative impact on the environment they will be OK with it, but if it just leaves another mess for future generations then they will be opposed.

I’m trying to get the emotional strength together to email the Institute for Social Ecology about it, that should give me a better answer than a few shallow NYT articles.


In theory, it sounds better than surface mining. Obviously, the devil is in the execution. And I have no idea how that works.


Full vegetable alchemist.


Conventional cotton farming is one of the most water- and soil-polluting, pesticide-intensive kinds of farming in the U.S. It is awful. Good people: please do what you can to use up, wear out and don’t prematurely rubbish your cotton clothing–the embedded costs are manifold and ugly. And bad.

Totally depressing.
I eat a lot of rice.
Just usually rice that is not grown in the U.S., whose farmers usually top the list of highest arsenic content in rice production.

Arsenic is a common mineral in the soil and water. Some take up less, some take up more. Rice takes up more, relative to, for instance, millet and quinoa.

Consumer Reports found measurable levels of arsenic in almost all the 60 rice types it checked, noting that the mineral is also found in rice pasta, drinks and cereals.

The worst offender is brown rice, which has the highest values of “good” minerals of all the rices but also the highest concentration of inorganic arsenic. (Organic rice is supposed to have lesser amounts of pesticides, not natural toxins like arsenic, by the way.)

Well, uh, Haaretz got part of the story right but they’re leaving a lot out.

One problem that the perfectly respectable and much-lauded Lundberg rice farming family had with their organic rice production was that they were using poultry manure to fertilize their fields. You’d think this would be a good idea. But. (And with sincere apologies that this is a very unbrief obstacle course of info…) TL;DR… ya gotta watch out eating chicken/eggs too unless eating organic versions (it ain’t just the rice with problems). Sorry.

  1. One reason some farmers use poultry manure is because cow (and other grazers’) manures often contain aminopyralids and clopyralids–pesticides that hay farmers will spray in order to manage weeds in their hayfields. These pesticides have an adverse (i.e. fatal) relationship with some human food crops entirely–like beans–and have well-documented negative health effects on humans. So… why not choose a manure-based fertilizer, especially one that is OMRI-listed, like poultry manure (aka “desiccated poultry litter” etc.) and avoid potentially borking your crops with -pyralids?

  2. If the farmer is lucky enough to get her hands on a supplier of organic poultry litter then it’s all to the good. Home and dry! Organic poultry litter is unfortunately not so easy to find because there are just not as many organic poultry farmers as there are conventional ag poultry farmers. Problems come with what the conventionally-raised poultry are eating: arsenic in their commercially-produced conventional chicken feed.

  3. All chickens that can be sold for meat, sooner or later, are sold for slaughter and then enter the food supply chain as either a human-food-grade meat or a lesser-quality meat destined for pet food or even yes farm animal chow (including in some cases chicken feed, don’t ask). A chicken can be bred as an egg layer, or as a meat animal, or maybe the farmer is raising dual purpose chickens, whatever but all conventional chickens eat conventional scratch (chicken feed) etc. And conventional feed manufacturers know that chickens end up as meat, so they add a lil’ sum’n to make the butchered raw meat look a little bit pinker and more commercially appealing as it sits, in the best case scenario, in the refrigerator case, lying in a styrofoam tray with a big sheet of plastic clingfilm over it, waiting for a human to buy it. Arsenic pinkens raw chicken meat. It is a bit harder to sell gray raw meat, generally, yes.

  4. At some point after the Lundbergs had unintentionally contaminated their previously well-stewarded farm fields with arsenic-laced poultry litter, the U.S. FDA sorta kinda banned “most” arsenic from “most” chicken feed. Behold (2013):

Nearly four years — yes, four years — after the Center for Food Safety filed a petition (PDF) with the FDA calling for the withdrawal of arsenic-laced feed given to chickens, turkeys, and pigs, the FDA has finally responded. Actually, it responded to the lawsuit that the CFS subsequently filed, demanding that the agency respond to the citizen petition.

Better late than never, right? But the response was bittersweet. The FDA only agreed to withdraw three of the four arsenicals on the market: roxarsone, carbarsone, and arsanilic acid. (Ironically, it banned these drugs after the companies that make them, Zoetis and Fleming Laboratories, decided to voluntarily withdraw them from FDA approval last month.) The fourth drug, nitarsone, is still allowed in the feed supply. As for what makes nitarsone “safer” than the other arsenicals being banned, that part is still unclear…
… The poultry industry has claimed that the arsenic fed to their birds has no adverse health effects on the consumer. This is because the kind of arsenic used in feed additives is “organic” arsenic, which is arguably less toxic than “inorganic” arsenic, a known carcinogen. But even the FDA acknowledges (PDF) that recent studies have found that organic arsenic has the ability to convert to inorganic arsenic in animal tissue – the animal tissue that you eat…


Ok, so back to arsenic in rice.
Arsenic is bad. We know. Bad bad bad.
Don’t feed bad stuff to kids (agreed!), whose body mass and fast growth phases will create a much heavier and worse lifelong body burden than grownups eating bad arsenic-y rice. Heavy metals are bad for human brain development and all our other parts too.

But rice is in a lot of things besides food. It’s in Anheuser-Busch “beer” which I can already guess that you, @docosc , assiduously avoid unless maybe dying of thirst. It’s in building materials. It’s used as biomass to generate energy (better hope that those combustion plants have high quality scrubbers on their exhaust stacks because otherwise the arsenic is airborne upon burning). So there are still grounds (haha) to make the argument that we must expel all heavy metals from all links in our food chain, starting with soil and ending with air and water. In a perfect world, or at least one of the better-funded, science-respectin’ EU countries, this would be or is already happening.

The strange thing is that there is a justifiable case for bioremediating farming disasters like (and I am not picking on the Lundbergs, they just have been in the news a lot, they are truly paragons of soil and farm stewardship and we need a million more like them) nice organic rice farmers and the greater farming community. It’s just the scale of the problem (the size of the affected land area) is sometimes too vast for most farmers, whose ROIs and profit-margins are thin to begin with, to pay to get the soil back to a better nutrient profile with more life and less heavy metals.


I believe you are way more up to speed than I am on what Murray Bookchin would say. My most recent reading has been this meta piece:

Murray Bookchin publicly debated Bahro and Dave Foreman, reproaching both men for their authoritarian approach to climate change. Bookchin argued that environmentalism without socialism was sure to end in disaster. When Bahro accused him of ignoring the “dark side” of humanity, Bookchin replied that the “dark side” of human nature emerges from a social foundation that we choose to indulge. A would-be ecological dictatorship, Bookchin told Bahro, “would not be ecological — it would finally finish off the planet altogether.”

Humans will not be able to live on a dead planet. And my guess is that Bookchin would view any extractive industries that can’t be closed-loop sustainable, nontoxic, net-positive etc. as not desirable for us or our home planet. From what I have seen, read, and understand (and I admit this could all be confirmation bias), extractive industries/economies invariably are opposed to having a viable environment with healthy soil, clean air and clean water. And they trend authoritarian.

ETA: pullquote from cited article and clarification


Wasn’t it Carlin who pointed out “Save the Planet” is silly? The planet will be fine. We’re screwed.

No worries on the arsenic beer for me. My bees supply my honey, my organically grown trees and bushes supply my fruits and my garden supplies the herbs and spices for my meads, which takes care of my alcohol. My understanding of the As/rice link here in the eastern US is that it largely grows where cotton was previously grown, and in the 20’s and 30’s the pesticides they used were As-based. Hence high levels in soil, accumulated by rice. Heavy metals really re the gift that keeps giving.


Oh there’s a lot more folks sayin’ suchlike than George Carlin. FTA (above):

I am not willing or ready to make the argument that humans should die already and just let nature have her way. I will not lump all people together as One Big Problem because it is simply not true.

It is true that nature will always have the last word. Final say. With or without us. Our human sense of time and scale are ridiculously narrow and tiny compared with geologic or astronomical time.


Mine too.
The “organic [brown] rice + poultry manure” angle was my “yes and” to the contaminated cotton fields problem.

Oh yes.
It’s staggering, the scope and scale of it.
Chelation might be one tool in the human health toolkit but avoiding heavy metals in the first place would be preferable.

Btw I got some jun for my birthday.
It is remarkable stuff and has a very complex flavor.

We keep bees too, so I’m halfway ready. I am saving some of the bottle to start my own batch! I will have to ask my friend to coach me. I only brew kombucha.

ETA: clarification and addnl quote

That sounds fascinating. Can you use kombucha scobies to ferment it? Lord knows we have those out the wazoo. I have made them into jerky (not bad) and gummies (taste like apple pie!) and composted gobs of them. Might have to try that as an experiment.

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I didn’t see it as fatalistic, but a paradigm shift that conservation has some selfish interests instead of just externalizing it to “the environment.” I think people often forget they live here, how small the world can be, and the knock on effects of seemingly small changes.


The SCOBY for jun is definitely different and my friend tells me there’s a second fermentation, anaerobic, that can push the alcohol content up to ~18%.

Kombucha tops out at a few percent total alcohol level.

I apologize for being off-topic.
I suppose I really ought to split this fermentation discussion off to its own thread…


I wonder how often these contaminated sites have the right climate for the right tree?

Sure, but avoiding them all that successfully sounds well nigh impossible.

I’ve heard cilantro is a chelating edible. But then, wouldn’t eating it extract all the nice iron I just got from eating spinach? :woman_shrugging:

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