Thread by @NaturesPoisons

A toxicologist's take on the ONLY MURDERS IN THE BUILDING finale.
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SPOILER ALERT
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SPOILER ALERT
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YOU'VE BEEN WARNED
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Let's dive into the murder and poisoning of Tim Kono, and other things, a 🧵:

Tim Kono's autopsy report revealed the immediate cause of death was acute secobarbital poisoning. So what's secobarbital? It's a barbiturate, a class of drugs used for anxiety, as a sleep aid, and for seizures. They are widely called "sedative-hypnotics" because they....sedate.

So far, so good. Jan poisons Tim with secobarbital and we see Tim become drowsy, confused, and unable to move freely. This generally fits with secobarbital overdoses and toxicity and mimics what you might expect from alcohol intoxication.

This isn't a "how to" guide, but the keys to a good poisoning are:
1. Access to the poison
2. Access to the person
3. Delivery of the poison

The reason I dislike poisoners is that they have so many opportunities to say "Nah, this is a bad idea," and back out, but they don't. They are also personally close to the victim, so they don't attract suspicion, and are smiling at you while they murder you. They suck.

Back to the show:
Could Jan have access to secobarbital? Yeah, it's not as common as it once was, but if you raided an old person's medicine cabinet, you could find some. In fact, we saw a collection of "Jan's Toxic Pills" or whatever it was called. This is totally plausible.

Did Jan have access to Tim? I should rephrase that, but yeah, obviously. They had a whole thing going on and I'm not going there, but in short, Tim had a relationship with Jan and had no reason to suspect she'd poison him, even after the break up.

So about the poisoning. She slipped secobarbital into Tim's drink, an Old Fashioned. Secobarbital is a white powder or crystalline solid that is soluble in water and ethanol, so it's *possible* to mix into a drink, but this is where we hit our first roadblock.

Secobarbital has a solubility of about 1500 milligrams (mg) in 1 liter of water. If his drink was 3 ounces of liquid, about 0.10 liters, she might be able to dissolve 150 mg into it. The problem is it won't dissolve quickly and cleanly, you'd still see solids floating around.

When you add salt - hella soluble in water - to your pasta water, does it immediately dissolve? No, it settles to the bottom and swirls around for a while. The same thing would happen here, but even more so in an ice-cold drink. And the glass was clear so you'd be able to see it.

The fact is, slipping a drug or pill into a drink doesn't work like TV and the movies would have you believe. They just don't dissolve quickly or cleanly. But let's suspend belief and say he drank all of his drink and consumed 150 mg of secobarbital, would he be near comatose?

No. He might feel intoxicated and slur his words, but incapacitated? No. Most secobarbital capsules are 100 mg, and 50% more wouldn't knock him out. To achieve a coma-like state, well over 2,000 mg would be needed. She's not dissolving that much in his drink. It's not happening.

TRIGGER WARNING: the accidental cat poisoning.
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Now about the cat that died from drinking Tim Kono's drug-laden blood. If Tim consumed 150 mg of secobarbital, his blood concentration would be about 1.5 mg per liter of blood. What's that mean?

Therapeutic barbiturate doses for pets vary, but let's put it at 5 mg. That means the cat would have to drink 3 liters of Tim's blood just for sedation. Tim doesn't have enough blood for a kitty overdose, even if he took massive quantities of secobarbital 🐱🩸

So the tl;dr for Evelyn the Sixth is that she(?) couldn't have died fro a secobarbital overdose from drinking Tim's blood.

Now, what about Charles? He was poisoned by Jan with secobarbital, but not in a drink like Tim, but by inhaling it from a handkerchief? What? That's so not a thing. Secobarb isn't a volatile substance like chloroform. That part doesn't fly *at all* but it was funny, so who cares.

I also take issue with Tim's cause of death. Going with an overdose cause of death over a gunshot wound to the head. They'd have to *really* know a lot about the case - and know he was dead before the shooting - to make that call. And it would have to be a homicide.

So that's my quick take on the finale of ONLY MURDERS IN THE BUILDING. It was a fun ride, even if the tox portions didn't make sense to me. But that's OK. There are probably bassoon parts that aren't realistic and I'd never know it, yet I still enjoyed it, and so did you I hope.

And if you have toxicology or forensics questions about the show...Ask Me Anything.