GUY RAZ, HOST:
Over the past five years, almost a dozen Western tourists - all young, mostly women - who've been traveling in Southeast Asia have died quickly and unexpectedly under mysterious circumstances. All of those cases caught the attention of science writer Deborah Blum, who's written about them for Wired magazine. She was interested in what happened largely because Deborah Blum is one of the foremost experts on poison. She even wrote a book about it. In fact, she knows so much about poison that she could probably kill you and me and anyone else and get away with it.
DEBORAH BLUM: My husband does not drink coffee with me in the same room.
BLUM: He hasn't for years.
RAZ: Anyway, back to the story. Deborah Blum first heard about these mysterious deaths this past summer. Two Canadian sisters, Audrey and Noemi Belanger, set off on a trip to Thailand in June.
BLUM: They were doing a sister vacation in the beautiful resort island. I've seen this described as a kind of 20-something rite of passage vacation. You go, you hang out on these beautiful beaches, you drink cocktails.
RAZ: The islands are famous for their white sand beaches, and at night...
BLUM: Especially after dark, the beaches of these islands become the epic cocktail party. And one of the things that a lot of the tourists there drink are called bucket drinks, where people will come to your table or your chair or where you're sitting in the sand, and they'll mix up a drink for you.
RAZ: And it was at one of these after-dark beach parties where local police say the sisters ingested DEET, which is better known as the chemical known to repel mosquitoes. But why DEET? Well, Thai investigators say it's a common ingredient in those bucket drinks because it creates a high. Now, that theory didn't sit right with Deborah Blum.
BLUM: So the first thing I thought when I saw DEET was how much DEET would you have to drink to have that kind of reaction, because everyone I know in the world has had some DEET exposure. The explanation by the police were so devious and made so little sense. When I did continuing research on the bucket cocktail theory, I don't know where that came from. There's absolutely zero evidence that DEET is used in bucket cocktails.
RAZ: They went to a party.
RAZ: That was where they were last seen, and then the next day, they were found dead in their hotel rooms.
BLUM: That's exactly right. These were very gruesome deaths. And I've asked myself this, you know, did no one hear them? Did they not call for help?
RAZ: About a month later, in Vietnam, something similar happened. Two women in their mid-20s: an American from Wisconsin, Kari Bowerman, and a Canadian named Cathy Huynh.
BLUM: And they were taking a vacation and backpacking through Vietnam. And they stopped one night at a touristy beach town. They arrived one day, the next day, they were in the hospital. And they were, both of them, suffering from symptoms of what looked like an acute poisoning, incredible difficulty breathing. They were hypotensive, their blood pressure was plummeting, they were acutely nauseated, they were slipping in and out of consciousness.
RAZ: Cathy was eventually discharged from the hospital. When she returned later that night to visit Kari, she found out her friend was dead, and two days later, so was she.
BLUM: My understanding is that the Vietnamese had the Canadian woman cremated. They haven't sent the results. They haven't told what chemicals they tested for. They haven't provided any of the actual details. They just said, no, no, no. It couldn't possibly be poison.
RAZ: These four deaths are part of a larger pattern: nine deaths in the last year and a half in Thailand and Vietnam - all Western tourists, mostly young, seven of them in just one Thai hotel.
The theory there - and this was raised with these two women in Vietnam - was that they were using an organophosphate pesticide. It's called chlorpyrifos, which is actually banned in buildings in the United States. It's been used heavily and widely in some of these Asian countries to fight bedbugs. The reason, though, chlorpyrifos is banned in residential spaces in the United States is not because it's phenomenally toxic but because it's linked to developmental problems. In other words, if you had kids in the building.
Why would it kill them and not other people presumably exposed to this in a hotel?
BLUM: See, that doesn't make any sense, does it? Because if you're doing widespread fumigation for bedbugs, it's not like you're just picking one room.
RAZ: Do you think insecticides and DEET had anything to do with the deaths of these women?
BLUM: I find the DEET very ludicrous. I mean, I can't even figure out where they came up with it. I've heard from scientists who studied DEET who say the same thing. So, I - no, I don't think it's DEET. Do we have any good police work that tells us what that poison was? We don't. Is there a good reason to suspect that some of this might be deliberate? Yeah, I think there - it makes a lot of sense. And if I just go back to these young women on Phi Phi Island, why would two young girls, out of the crowds of people on the beach, be the only ones who die from a poison cocktail? That doesn't sound to me like, you know, you're randomly drinking the popular beach drink. That sounds to me like someone picked you out.
RAZ: Deborah Blum is still investigating these cases. In Thailand, police say they concluded theirs this week. The deaths, they say, were caused by DEET. You can find more on this story at Deborah Blum's blog, elemental.wired.com.
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RAZ: You're listening to ALL THINGS CONSIDERED from NPR News.
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