#call me mark watney how i be doing botany for fun

[aspensmonster]

"It is poisonous to humans,[5] dogs, cats, and horses.[13] All parts of the plant are toxic, and the plant contains cardiac glycosides.[5] The plant is toxic both green and dried.[14] The stems contain a white sap capable of causing skin blisters.[15]"

Tracking down the sources (5) leads to https://pfaf.org/user/Plant.aspx?LatinName=Apocynum+cannabinum, which in turn cites four sources for its toxicity at https://pfaf.org/user/cmspage.aspx?pageid=174 (1, 4, 19, 62).

Checking out one of those sources (62, from 1982), found it on Anna's archive: https://annas-archive.org/md5/3e8a8a8148cbc2c2afb4b960614a0a87 (also borrowable from IA, though it's timing out for me: https://archive.org/details/fieldguidetonort0000elia/page/282/mode/2up ).

Not exactly super helpful -__- Doing a search on Anna's Archive for just "dogbane" does give this scholarly source though: "Medical Toxicology of Natural Substances || Dogbane Family and Cardenolides" (10.1002/9780470330319.ch147) (https://annas-archive.org/md5/1e3c8186cfe91266972a50468f0fe835).

"The most commonly mentioned folk use was as an abortifacient."

(Well that's a fun side-quest; back to what/how it's poisonous)

"Common oleander contains several cardiac glycosides (oleandrin, digitoxigenin, neriantin, rosagenin) that produce a digitoxin- like effect by inhibiting the sodium - potassium adenosine triphosphatase enzyme system. These cardiac glycosides bind to an extracellular portion of the Na + /K + ATPases and cause increased intracellular calcium concentrations. Minor glycosides in oleander with limited cardiac activity include adynerigenin, adigoside, digitalin, and uzarigenin.11 Because of the lack of toxicokinetics data, the identities of the toxic glycosides or toxic metabolites remain unclear."

"Of over 400 cardiac glycosides isolated from the plant kingdom, most of the cardiac glycosides occur in extracts from the milkweed (Asclepiadaceae), figwort (Scrophulariaceae), lily (Liliaceae), and dogbane (Apocynaceae) families. The highest concentrations of cardiac glycosides are found in seed, stems, and roots, followed by the fruit and leaves. However, the leaves contain the greatest oleandrin concentrations. The concentration of oleandrin varies widely between various strains and species of oleander."

"Oleander poisoning resembles digitoxin poisoning with the predominant symptoms involving the gastrointestinal and cardiac systems. Serious oleander intoxication usually occurs following the ingestion of teas prepared from oleander leaves rather than from the ingestion of plant parts.21 – 23 The bitter taste of the oleander leaves limits the ingestion of oleander leaves in children. Characteristic features of serious oleander poisoning include confusion, marked hyperkalemia, conduction abnormalities, and ventricular arrhythmias. Nausea and vomiting usually occur within several hours, and gastrointestinal symptoms are more prominent following oleander poisoning than following digoxin toxicity. Increased salivation, dry mouth, burning of the mouth, and paraesthesias of the tongue may develop as a result of the local effects of oleander extracts.22 Case reports indicate that the astringent properties of oleander sap produce mucosal irritation.24 The most common serious complication of oleander poisoning is disruption of cardiac conduction.25 Cardiogenic shock, ventricular fibrillation, and cardiovascular collapse may occur following severe oleander toxicity. Conduction delays may persist 3– 6 days, and these cardiac effects resemble classical digitalis toxicity (e.g., conduction abnormalities with ectopy, such as supraventricular tachycardia with atrioventricular block).23,26"

Alright. So... definitely don't eat off of it, and definitely don't make tea with it (the source mentions a case where tea was purposely prepared and ingested, presumably as a suicide attempt). But assuming you aren't trying to ingest it... then sure? It's probably safe as a base for textiles? I suppose the biggest risk would be the textile getting wet and leaching cardiac glycosides, assuming that those glycosides remain in sufficient quantity after processing the stems.

"Although one leaf has been considered potentially lethal, ingestion of larger amounts is probably necessary to produce serious toxicity. Using calculations on the digoxin pharmacokinetic in the antemortem serum from a 96 - year- old woman who died after ingesting oleander tea, Osterloh et al estimated that the apparent digoxin concentration of 5.8 ng/mL was equivalent to the absorption of cardiac glycosides from 5– 15 Nerium leaves.19 The postmortem examination did not demonstrate any evidence of coronary artery disease. Using a crude oleander extract prepared by ethanol extraction, lead acetate purification, and solvent partition, the group estimated that 100 ng/mL of crude extract produced a 1 ng/mL false elevation of the digoxin concentration. Assuming the Vd of digitoxin was 1 L/kg, the estimated absorbed dose of cardiac glycosides was approximately 4 grams, which was equivalent to 5– 15 oleander leaves."

Hmmm. The leaves have greater concentrations than the stems according to the source, so... probably not a huge risk unless you're recycling water without treating it? Or perhaps during the processing of the plant, those that do the processing might consider it an occupational hazard? I mean, if you wanted to have large crops of it, then I'd imagine you'd need certain precautions when processing on an industrial scale.

I mean, at this point, I'm invested and wanna read more. @headspace-hotel, what sources do you have for "In terms of the quality and usefulness of fiber and the amount you get out of it relative to the amount of work it just blows everything else out of the water"? I figure there's a reason that cotton ended up the most used fiber of the textile industry and not any other.

Also @therobotmonster, @teeth-and-spackle, @oldmanyellsatcloud, @cryptidroots, @ilovemosss, probably several other folks that seemed interested in this that I've missed (can't scroll through the reblogs forever).

also I ended up looking at stuff about soviet agricultural experiments and apparently dogbane (Apocyonum cannabinum) was introduced to the USSR as a fiber crop plant? ???