Heavy metal in soil

Has anyone here ever tested or seen tested soil for heavy metals? I’m interested in learning more about heavy metal present at homesites and public lands. (How might it vary or change over time? What does it matter?) We garden and forage, but I am surprised I don’t see much mention or discussion of the possibility of bioaccumulation of heavy metals.
Thanks!

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Hmmm… had not thought about that before, but it Seems like a reasonable step, especially in urban areas or areas with a history of contamination (superfund sites, e.g.)

https://clf.jhsph.edu/sites/default/files/2019-03/suh-soil-testing-guide-2019.pdf

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If you know anywhere to get cheap arsenic and mercury tests I’d love to find out the danger zones for my town.
We all know not to eat berries in the coal duff banks, yet everyone still gardens, even if they live like 300m away downhill. I don’t think anyone really knows how far away is safe. I have some rules of thumb for avoiding making myself sick, but I won’t know how good they are until I get sick myself or find a way to test.

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There is a table at the end of the Safe Urban Harvests pamphlet (URL above) that lists heavy metal tests in a variety of price ranges, along with the links to each of the labs. Or, Perhaps, were you looking for DIY tests?

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Was looking for DIY where I wanted to test various streams. On social assistance so 30 dollars a sample is prohibitive.

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I hope you can, perhaps, get a grant to provide funds to do such beneficial work for your community.

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Hopefully asking the question magically provides answers.
I’m sure it’s a legal requirement to check for these things, but if it’s being done, no one knows where the results would be found lol.

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Rule of thumb about heavy metals in soil is they don’t move much once they are there. So 300m is probably safe from, say, lead paint chipped off an old building. It’s not safe from metals in nearby air emissions if you are downwind. A mile might be enough because metals tend to drop out rather than get transported long-distance via air, but it depends. I live near a freeway. The soil here probably isn’t great for that reason (if no others). Any veggies I grow are in pots.

Metals in groundwater don’t move fast (groundwater does not move fast) but they do move. Where and in what amount needs to be analyzed with knowledge of local conditions. Metals in surface water (i.e., streams) can move as fast as the streams do if they are dissolved, or settle out in slow spots if they are on particles. Again, need some details and local knowledge.

Places to look for monitoring data like that are whatever State environmental department handles Clean Water Act or other water law regs; any data collected pursuant to such laws is a public record. If you have a water district, they should be testing their wells; if you have actual wells, the State and local drinking water folks should know what’s in them.

Anyway, places to start. Be patient, be persistent, and know your legal rights - and good luck!

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I remember reading that at least some shrooms “love” them and even quite far away from roads they can consist of a lot of heavy netals.

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Yes, there have been many studies primarily on edible mushrooms being heavy metal accumulators. Here is one paper. Search on “heavy metal accumulation mushroom” for more.
https://www.researchgate.net/publication/297346787_Heavy_metal_contents_and_bioaccumulation_potential_of_some_wild_edible_mushrooms

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<$30.00/sample is going to be fairly restrictive, especially for soil samples which typically require some type of extraction before a measurement can be taken. Typically, if you want to know concentrations of heavy metals in soils, you need to send samples to a lab with an ICP/MS or other analytical equipment.

For water samples, Hach offers several in-field colorimetric tests for some specific types of metals (there are high and low-concentration Hach kits available for arsenic, but there are no colorimetric kits available for mercury). If you have some chemistry background and the right place to work, you could potentially perform the extraction yourself and use a Hach kit on the extract to get rough numbers (they won’t give you precise concentrations, generally just an approximate range). However, there is a safety risk involved with the reagents used for the extraction, and performing it incorrectly will skew your results, so I would not recommend that a layman try this. Additionally, the Hach kits do generate hazardous waste that has to be disposed of properly, which usually incurs some additional cost.

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What precisely do you want to know? I work on remediation projects at formerly-used defense sites, which can involve testing of soil and groundwater samples for heavy metals, so I may be able to help.

I can tell you that bioaccumulation of heavy metals does occur, and it’s even employed as a strategy for remediation of areas contaminated with heavy metals (If you want to know more, you can do some googling for “phytoremediation of heavy metals” to get started. EPA.gov and Clu-in.org are good places to look, too). Public lands that have undergone some type of remediation (and there are quite a lot of those) will have some record of site and remedial investigations that include information on any heavy metals testing that was performed.

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I have started an amateur research project on heavy metals in mushrooms. Introduction and initial report here. The problem is not so much making yourself sick after eating contaminated food once, although it can happen, but more accumulation over the longer term. The pandemic has slowed the project but I hope to pick it up again this fall.

The cost per sample is relatively high when sending to a professional lab for ICP/MS >$50. Another option is to use a XRF Spectroscopy gun, it is something we plan to do but hasn’t happen yet. This is only helpful if you know someone/an organization that has access to a XRF Spectroscopy gun.

Let me know if you have any questions

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