Piteraman wrote:
Can you post any information you have on its toxicity? Real facts like from universities and such.
Hopefully, we can assemble factual information on this post.
I learned a bit about oxalic acid in a class I took. I think this is the type of information you are looking for Piteraman.
Spinach (high), soy beans, peanuts, asparagus and chocolate contain oxalic acid.
A diet high in oxalic acid is a concern for kidney stones.
For ingestion, the concentration of oxalic acid is the concern. In plants, the concentration of oxalic acid is fairly dilute. High concentrations of oxalic acid are toxic to living plant tissue also.
Obviously drying a plant will concentrate its crystalline oxalic acid content.
Oxalic acid is typically combined with calcium in plant and animal tissue. Calcium oxalate crystals are small and sharp. The crystals can cause Chemical Irritant Contact Dermatitis (CICD).
EDIT:
Calcium Oxalate
Found in many genera of plants, calcium oxalate is a water-insoluble salt that forms bundles of needlelike crystals called raphides. Contact with moisture causes plant cells to eject the raphides, which can then come into contact with skin or mucosal surfaces. Irritancy is mechanical in part and due to the anatomically sharp structure of the crystals themselves. The crystals are believed to be more irritant when longer than 180 µm.[21] The raphides of calcium oxalate have been classified historically as a chemical irritant mainly because they allow the penetration of other plant chemical toxins (including proteases, saponins, and other chemicals) that may not normally breach the skin on contact. They also enhance the penetration of known skin irritants, including many alkaloids from daffodil bulbs, bromelain in pineapples, and saponins in Dieffenbachia.
Agave. Agave spp are laden with calcium oxalate raphides and saponins. A single droplet (0.03 mL) of juice extracted from the leaves of the agave plant is reported to contain hundreds of calcium oxalate raphides, each as long as 500 µm.[24] These crystals and saponins are the presumptive source of the marked pruritus and stinging associated with exposure to the agave plant.[3] The plant is indigenous to North America, and the fruit of some species (including Agave tequilana) is used in the production of tequila. On agave plantations and in tequila distilleries, CICD (Chemical Irritant Contact Dermatitis) related to agave is more routinely seen.
This is the MSDS for “concentrated” commercial, reagent grade (pure) Oxalic Acid Dihydrate. (Not likely found in dried agave,)
http://avogadro.chem.iastate.edu/MSDS/oxalic_acid-2H2O.htm
