Heavy metals in rock dust

clongo

Active Member
That's a great point. Another is Bentonite clay, which might contain some heavy metals to begin with but which is also used in heavy metal remediation. I just wonder how long they hold onto the metals before giving them back up-I'm no chemistry expert obviously lol. I've been looking into the use of zeolite in living soils. It's an aluminosilicate like bentonite and azomite so I'm not sure what that means for aluminum levels when using fulvic acid, but it has some very useful properties-huge surface area for rhizobacteria, high cec, water retention, etc, seems to have a lot of overlapping benefits with biochar.
Were you ever able to find lists of ingredients with no detectable heavy metals?
 

Rurumo

Well-Known Member
Were you ever able to find lists of ingredients with no detectable heavy metals?
Hi there. For the most part, I was able to put together a clean mix, but I haven't used the soil in the way I intended yet. A few months ago I contracted Covid one day before I was due to transplant my current plants into their final "home" which was a 4x4 indoor bed using this soil. Well, the day comes around when I needed to move that massive pile of soil inside and I couldn't get out of bed. So, I ended up dumping some of it into the biggest pots I had available which were 3.5 gal air pots....I knew it was a mistake, and if I had coco on hand I would have just used that and gone with another Maxibloom grow. Anyway, you can predict what happened, amazing veg growth-some of the best I've ever seen, then problems developed during stretch due to the small pot size and I had to start feeding additional nutes. So it wasn't a good test of the soil I made, but I still have the bulk of it in my front yard wrapped up in a tarp lol.

Let me know if there is any particular soil amendment or nutrient you are interested in and I can tell you what I found regarding heavy metals. Pretty much any aspect of the soil we make can be problematic depending on the source. Even things like perlite had led in some of the brands. My goal was "no detectable level" in everything I bought and for the most part I was able to stick with that. It makes me sad when I think about regular "organic" grows where "organic" is the goal and people don't check for heavy metals in their products, because I promise you, the average organic grow will have vastly more heavy metal content than a simple grow using coco and Jacks (a common combination) for example. People are so worried about pesticides, herbicides, and "natural" sourcing, that they ignore the most dangerous and pervasive toxins in our environment-heavy metals.

I never did make a list because I noticed that some brands might be clean at one point, then metals started showing up later on, so really the best thing you can do is look up everything in the heavy metal database, look at the latest test reports, and if they aren't listed, go with another product. Rock dust, all types, and seaweed, especially dry extracts, or ground kelp, are two of the most heavily polluted products. Some liquid seaweed products are totally free of arsenic however, but I couldn't find a single rock dust that is. Rock phosphate and greensand as well. Companies like Jack's and General Hydro (maxibloom) are probably able to reduce the heavy metal content of their phosphates during the refining process.

I feel a bit bad about making this thread to begin with, because I know how I felt when I realized the expensive soil I had been using for years was producing weed that would most likely either fail a heavy metal test, or at least throw up numbers I'm not comfortable with. But for people just starting out, who have yet to invest in this hobby, they can reduce their exposure greatly if it's a concern. I will personally never get tested for heavy metals because I'm certain my bones are riddled with them like a sickly Wolverine, but I hate that the government permits ANY LEVEL of them in fertilizer, because over time even trace amounts build up in the soil until they become a problem, and then it's too late to do anything about it. There is already a strong causal link between certain bioaccumulating crops, like brassica family crops, and cadmium exposure to breast cancer.

Sorry for the long post!
 

clongo

Active Member
Aren't breeders up on cadmium resistance via lab assisted calcium channel analysis? Surely cannabis labs are helping breed cannabis?

It's kinda the whole point of breeding skunk isn't it? To get the heavy metal-thiol reaction? Not really another way to get that response.
Thiols need sulfur
 

clongo

Active Member
Hi there. For the most part, I was able to put together a clean mix, but I haven't used the soil in the way I intended yet. A few months ago I contracted Covid one day before I was due to transplant my current plants into their final "home" which was a 4x4 indoor bed using this soil. Well, the day comes around when I needed to move that massive pile of soil inside and I couldn't get out of bed. So, I ended up dumping some of it into the biggest pots I had available which were 3.5 gal air pots....I knew it was a mistake, and if I had coco on hand I would have just used that and gone with another Maxibloom grow. Anyway, you can predict what happened, amazing veg growth-some of the best I've ever seen, then problems developed during stretch due to the small pot size and I had to start feeding additional nutes. So it wasn't a good test of the soil I made, but I still have the bulk of it in my front yard wrapped up in a tarp lol.

Let me know if there is any particular soil amendment or nutrient you are interested in and I can tell you what I found regarding heavy metals. Pretty much any aspect of the soil we make can be problematic depending on the source. Even things like perlite had led in some of the brands. My goal was "no detectable level" in everything I bought and for the most part I was able to stick with that. It makes me sad when I think about regular "organic" grows where "organic" is the goal and people don't check for heavy metals in their products, because I promise you, the average organic grow will have vastly more heavy metal content than a simple grow using coco and Jacks (a common combination) for example. People are so worried about pesticides, herbicides, and "natural" sourcing, that they ignore the most dangerous and pervasive toxins in our environment-heavy metals.

I never did make a list because I noticed that some brands might be clean at one point, then metals started showing up later on, so really the best thing you can do is look up everything in the heavy metal database, look at the latest test reports, and if they aren't listed, go with another product. Rock dust, all types, and seaweed, especially dry extracts, or ground kelp, are two of the most heavily polluted products. Some liquid seaweed products are totally free of arsenic however, but I couldn't find a single rock dust that is. Rock phosphate and greensand as well. Companies like Jack's and General Hydro (maxibloom) are probably able to reduce the heavy metal content of their phosphates during the refining process.

I feel a bit bad about making this thread to begin with, because I know how I felt when I realized the expensive soil I had been using for years was producing weed that would most likely either fail a heavy metal test, or at least throw up numbers I'm not comfortable with. But for people just starting out, who have yet to invest in this hobby, they can reduce their exposure greatly if it's a concern. I will personally never get tested for heavy metals because I'm certain my bones are riddled with them like a sickly Wolverine, but I hate that the government permits ANY LEVEL of them in fertilizer, because over time even trace amounts build up in the soil until they become a problem, and then it's too late to do anything about it. There is already a strong causal link between certain bioaccumulating crops, like brassica family crops, and cadmium exposure to breast cancer.

Sorry for the long post!
I was looking for something nutritionally complete that I could top dress my blend with (coco/peat/perlite/ewc) bc I will have to keep bonsai plants due to space restrictions.

I have some jacks 30-30-30 but noticed the lead levels aren't great so will be using it for house plants instead.

The lack of policy action always seems premeditated to me somehow on public health issues.

Hope you are feeling better.
 

Rurumo

Well-Known Member
I was looking for something nutritionally complete that I could top dress my blend with (coco/peat/perlite/ewc) bc I will have to keep bonsai plants due to space restrictions.

I have some jacks 30-30-30 but noticed the lead levels aren't great so will be using it for house plants instead.

The lack of policy action always seems premeditated to me somehow on public health issues.

Hope you are feeling better.
Thanks, I'm doing much better. Some of the Jack's products test highish for some things, and others are NDL-I believe the 2 part that is popular here is pretty clean, but I'd have to double check. I remember the 30-30-30 being high in something and it always bothered me because Jack's big selling point is their "clean" well tested products. The last time I checked Maxibloom and several other Gen Hydro products were NDL for heavy metals, which surprised me at the time. I believe Dyna Gro Foliage Pro was also NDL for heavy metals. Also, I really like Megacrop on paper, but for some reason I can't find them in any of the state heavy metal databases-actually, I'm going to shoot them an email right this second.
 

clongo

Active Member
Thanks, I'm doing much better. Some of the Jack's products test highish for some things, and others are NDL-I believe the 2 part that is popular here is pretty clean, but I'd have to double check. I remember the 30-30-30 being high in something and it always bothered me because Jack's big selling point is their "clean" well tested products. The last time I checked Maxibloom and several other Gen Hydro products were NDL for heavy metals, which surprised me at the time. I believe Dyna Gro Foliage Pro was also NDL for heavy metals. Also, I really like Megacrop on paper, but for some reason I can't find them in any of the state heavy metal databases-actually, I'm going to shoot them an email right this second.
Thanks for the suggestions for some soluble feeds.

Something like biotabs or Gaia green 4-4-4 are also interesting bc my ultimate goal is water only through blumats. I saw that the age old organics dry blends are ND but they seem to be phasing those out.
 

Rurumo

Well-Known Member
Thanks for the suggestions for some soluble feeds.

Something like biotabs or Gaia green 4-4-4 are also interesting bc my ultimate goal is water only through blumats. I saw that the age old organics dry blends are ND but they seem to be phasing those out.
I really like Age Old products for a lot of things-the kelp extract is my favorite, potent and funky, and NDL (I think Neptune Harvest's kelp and their fish hydrolysate are also both NDL). I also use Age Old Grow for my mother plants. I'm trying to get away from bottled nutes too, I didn't even know they made dry nutrients. Another product universally high in heavy metals is crab (and lobster) meal, BUT shimp meal is usually totally clean!
 

Vbz.420

Well-Known Member
Whats up Rurumo. Glad to stumble across this thread And see what you said about rock dust. Thid goes for any kind of rock dust you say? Also have you read up on Roots Organic Bloom terp tea? Is there any contaminants in those we should know about ? since it isnt an OMRI product and i believe it has a website on its metals content but couldnt find much on
 

Rurumo

Well-Known Member
Whats up Rurumo. Glad to stumble across this thread And see what you said about rock dust. Thid goes for any kind of rock dust you say? Also have you read up on Roots Organic Bloom terp tea? Is there any contaminants in those we should know about ? since it isnt an OMRI product and i believe it has a website on its metals content but couldnt find much on
Hi there! Here is one of the state fertilizer databases, Oregon and Washington have them too and sometimes it's interesting to check the same product across all of them, this is California's: https://apps1.cdfa.ca.gov/fertilizerproducts/. Just an FYI, sometimes it can be super hard to find a product in them because sometimes they are listed under some company's name you aren't familiar with. I just searched "terp" and found your bloom tea, so you can find it that way. It does contain arsenic, cadmium, and lead in varying amounts. A lot of products contain arsenic and cadmium-most of the cadmium comes from phosphates, arsenic can come from a lot of things-seaweed, crustacean meals, etc. Lead is a bit more uncommon and it's really bad that it's in there, there is no excuse for a company to allow any level of these metals in their products. If General Hydroponics can make fertilizers with no detectable amount of heavy metals ANYONE can, AND still make a profit. Good on you for checking your nutes!
 

Rurumo

Well-Known Member
Another product category that is almost universally high in heavy metals is micronutrient packs. When I grow in Coots Mix I always add TM-7 at least twice, even though I know it contains some heavy metals, mainly because it was 100% necessary and the quantity we use is so small it didn't overly concern me. But after going on a mission to find a micronutrient pack with no detectable heavy metals, I couldn't find a single example. Some, like the Alaska brand micronutrients, are low in them, but also the dosage of micros is much lower than TM-7, so that makes sense. Some are quite high.

I just got back the test report from Greanleaf regarding Megacrop one part, which is my favorite one part mineral salt formula on paper. Did you see the italics? I feel like it added a dramatic element. Anyways...Greanleaf tests its raw materials and final product and claim to be low in heavy metals, which they are, but....due to the addition of dry seaweed extract, I knew it would have at least some arsenic. So, it turned out to have no detectable lead-excellent...a tiny bit of cadmium- .08 ppm (while the lower end testing limit is .03-ALSO GOOD. None is better, but these numbers don't scare me at all. Finally, it did have 4 ppm arsenic. This is still not bad compared to a lot of products, and it is probably coming from the kelp extract and the added micronutrients (Megacrop has all of them). Now, considering what I told you about micronutrients, a reading of 4 ppm arsenic is acceptable to me. It means that Greanleaf, like Jacks and General Hydro, is actually trying to source clean minerals. They aren't as low in arsenic as Jacks 2 part or Maxibloom simply because they added a micronutrient pack and seaweed extract to the formula. I consider any of these three formulas to be safe for long term use and would personally use any of them. While Maxibloom is currently the only complete one part formula to have no detectable heavy metals, it is also lacking in micronutrients, so there is a give and take going on.
 

FermentFred

Active Member
I've found a few interesting studies on the use of zeolites in agriculture, and their ability to bind heavy metals in soil as well as bind to the heavy metals found in fertilizers. See the section "heavy metal traps" great stuff! https://www.princeton.edu/~ota/disk2/1985/8512/851210.PDF
Came here to say this lol. I've read a tiny bit on the usage of bentonite clays (like azomite) for "detox" routines in people and the conensus seems to be that despite their heavy metal content, the clay/humic colloids are able to hold onto those metal cations so tightly that worrying about your gut absorbing them is a non-starter. Doesn't stop me from being paranoid though lol, or from wondering how different it is in the dirt.
 

Rurumo

Well-Known Member
Came here to say this lol. I've read a tiny bit on the usage of bentonite clays (like azomite) for "detox" routines in people and the conensus seems to be that despite their heavy metal content, the clay/humic colloids are able to hold onto those metal cations so tightly that worrying about your gut absorbing them is a non-starter. Doesn't stop me from being paranoid though lol, or from wondering how different it is in the dirt.
I gave up on the aluminosilicates simply because I'm concerned about the aluminum content of the finished bud. Aluminum is absorbed by plants at pretty low PH, but then again living soils can often hit a pretty low PH, and I wonder how much is absorbed at a more common PH. It is something I'd love to do a controlled test with, but for now, I'm leaving it alone. I think Biochar fits the bill quite nicely.
 

ComfortCreator

Well-Known Member
I gave up on the aluminosilicates simply because I'm concerned about the aluminum content of the finished bud. Aluminum is absorbed by plants at pretty low PH, but then again living soils can often hit a pretty low PH, and I wonder how much is absorbed at a more common PH. It is something I'd love to do a controlled test with, but for now, I'm leaving it alone. I think Biochar fits the bill quite nicely.
Curious if you have tested or seen tests that show elevated levels of the heavy metals in bud samples? I completely get your concerns. But wonder if worrying about the inputs is or isnt a crucial consideration?
 

GreenestBasterd

Well-Known Member
Some good reading here, thanks guys!

I recently put together 2 x 60l bins of coots mix with no rock dust at all for some landraces I’ll be running, as it says they’re rather sensitive.

I will put one of my regular clones I frequently run into it and do a comparison with the conventional coots mix.

Ill report back my very unscientific findings once established, but just want to compare them growth and taste wise.

Cheers
 

m4s73r

Well-Known Member
Well I guess I'm going to die a heavy metal brick lol. I been using BAS Craft blend since it came out. I have 2 4x4 beds that are cootz mixes. Been doing this now for 8 years. I dont even do much to it, grow and chop clover for mulch and water with saponin and some Mikrobs once a month. Otherwise I just grow, harvest, throw everything back on it, mow cover crop a couple of time and then drop in more plants. Guess I should get my soil and weed tested. Dont need to kill the family off with bad weed. Jeeze and I just thought I had to worry about spider mites and mold...
 
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