Injecting Potassium Cyanide: LD50 & Effects

[SkepticJ]

This is going to sound like a weird knowledge request, but are cyanide salts effectively introduced into a body by injection? If so, how does the LD50 compare with oral consumption?

I'm curious because I'm creating a character that throws poisoned knives and suchlike, and need to know how fast they'd be effective.

 

[aroc91]

LD50s for hydrogen cyanide have been estimated to be 1.1 mg/kg for intravenous administration and 100 mg/kg after skin exposure. The oral LD50s for sodium and potassium cyanide are about 100 and 200 mg/kg respectively.

Source: http://www.fas.org/nuke/guide/usa/doctrine/army/mmcch/Cyanide.htm

It was the first google result for "cyanide LD50." Not to be a dick, but that took no effort to find.

 

[SkepticJ]

Thank you, but that's intravenous for hydrogen cyanide--the gas. It, like all the other sources I found, doesn't mention if the salts work if injected.

 

[DanP]

Is KCN essential to your story ? There are alkaloids which are several hundred times more poisonous that HCN. And they where many times used to poison edged weapons and arrows.

 

[aroc91]

Thank you, but that's intravenous for hydrogen cyanide--the gas. It, like all the other sources I found, doesn't mention if the salts work if injected.

Ah, I didn't notice that.

http://www.epa.gov/IRIS/toxreviews/0060tr.pdf

Here you go-

In a related study from the same laboratory, i.p. injection of rats with 7 mg/kg KCN 92.8 mg/kg CN-) caused significant transient hearing loss... suggest that hearing loss from cyanide exposure is a potentially sensitive neurological marker of toxicity

They also mentioned NaCN, so yes, injected salts can be deadly.

 

[SkepticJ]

Is KCN essential to your story ? There are alkaloids which are several hundred times more poisonous that HCN. And they where many times used to poison edged weapons and arrows.

It's not the toxicity level, but the speed of action that is important to me. The wounds need to be lethal in a matter of a minute-to-a-few and have serious physiological effects almost immediately.

I've read that nicotine is pretty fast-acting. Saxitoxin is supposed to work in a matter of min., and its LD50 is tiny.