Pubdate: Thu, 17 Jul 2014
Source: Westword (Denver, CO)
Copyright: 2014 Village Voice Media
Website: http://www.westword.com/
Details: http://www.mapinc.org/media/1616
Author: William Breathes

HOW MUCH THC EQUALS A LETHAL DOSE?

Dear Stoner: I know that you cannot OD by smoking weed, but what
about ingesting it? There are some very strong eatables; what if I
get the munchies on marijuana chocolate bars? I would like to know the 
limits.

Garufa

Dear Garufa: If by "limits" you mean how much weed an otherwise
healthy person would have to ingest to literally die from THC, it's
surprisingly less than you'd think - but even so, you'd never be able
to come close to doing it. Allow us to drop some science. There's a
thing known as the "median lethal dose" for pretty much all foreign
chemicals we humans use and occasionally put in our bodies; it's
called an LD50 rating. Basically, it's how much of something someone
would have to ingest to die at least 50 percent of the time. (LD
stands for "lethal dose.")

For THC, there are varying figures, ranging from 1,260 milligrams of
THC per kilogram of body weight down to 666 mg/kg. Even going with the
lowest figure, a 175-pound man would have to consume more than 53
whole grams of pure THC all at once. And pure THC isn't something you
are going to find in even the purest shatter oils and waxes produced.
If we're talking commercially produced edibles, then you would
probably die from an overdose of salt (3,000 mg/kg) or sugar (1,100
mg/kg) before even coming close to the threshold for marijuana.

Need more perspective? Caffeine has an LD50 of 192 mg/kg, and nicotine
is around 60 mg/kg. Alcohol doesn't necessarily have an LD50 that
translates well, but if just .4 percent of your roughly 160 ounces of
blood contains booze, you're not likely to wake up. Even synthetic,
marijuana-derived pharmaceuticals have higher LD50 ratings than
natural marijuana.

Now, if you mean can you eat enough to get sick or have a bad time?
Absolutely - it happens to the best of us. I have gotten sick -
spinning head, a sinking feeling in my stomach - from a too-strong
edible (or seven). Or maybe it's just an overdose of chocolate.... In
any case, do I suggest finding your limits that way? No. And
unfortunately, I can't tell you how much you'd have to eat before
you'd boot your lunch - nor do I suggest finding out the hard way.
Stick with smaller doses and increase slowly each time you consume
until you find a comfortable level. And if you ever are truly
concerned about eating more pot food while you've got the munchies, we
advise taking a walk to the nearest 7-Eleven and going for Cheetos
instead.
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MAP posted-by: Matt