AUDIE CORNISH, HOST:
A spike in overdose deaths in this country is being driven by fentanyl. It's a synthetic opioid that can be 50 times stronger than heroin, and it's often mixed in with other drugs without a user knowing it's there. This danger is leading public health advocates to wonder, if users could test their drugs and understand what's really in their supply, would that keep them safer? Mary Harris of member station WNYC went to one needle exchange where this is happening.
MARY HARRIS, BYLINE: One of the first citizen scientists to get roped into this new experiment is a guy named Vincente Estepa.
VINCENTE ESTEPA: Testing - one, two, one, two - testing.
HARRIS: Estepa looks a lot younger than his 47 years. He's a regular at a place called St. Ann's Corner, where he knows just about everyone by their first names.
ESTEPA: This is Laurel. That's Eddie. And this is Dolores.
HARRIS: He's also a heroin user. St. Ann's Corner is a needle exchange.
ESTEPA: And I used to work and do all these great things. And now, ever since I started using, it's like a cockroach. You hide, and then you come out at night. So yeah, I would love to stop.
HARRIS: But he can't, not yet, so he comes here to get needles from Van Asher, who works out of a little storage room in the back.
ESTEPA: He's like my secretary right there. He works for me.
HARRIS: Estepa is pointing to a guy huddled over a computer surrounded by boxes of female condoms and syringes, who turns out to be the mastermind of this new experiment.
ESTEPA: You're doing an excellent job, sir, an excellent job, sir.
HARRIS: Asher's actual job is to collect data for the CDC and the city and state departments of health. But he looks up, rolls his desk chair over and says...
VAN ASHER: I work for the person who comes through the door. So yeah, I do work for you. You're my boss.
ESTEPA: And I appreciate that.
ASHER: And what do we have here?
HARRIS: Asher wants to know if telling users more about what they're shooting can keep them safer. Over the last year, he's watched as people who think they're using heroin die from overdoses involving fentanyl - so many people, it's becoming a blur.
ASHER: I'll hear so-and-so OD'd, and I'll be like - I'll think of them in terms of, OK, that's the 10th person this month before I think of them as a person.
HARRIS: So when was the last time you heard about an overdose death?
ASHER: Within the week, within the week.
HARRIS: So he found this website that would sell him test strips, the kind usually used by doctors to look for fentanyl in a patient's urine. He's been giving the strips out to heroin users not so they can test themselves but so they can test their drugs.
ASHER: If you have a second, if you want to come in, I can...
UNIDENTIFIED MAN: Sure.
ASHER: I could talk to you about how to use one. And I can give you one.
HARRIS: When a user comes up asking for needles, Asher tells them him how it works.
ASHER: So what you're going to do is you're going to draw your shot out and leave it in your syringe.
HARRIS: After mixing heroin in a cooker - that's a little cup that looks like a bottle cap - you can use the test strip to sop up the drug residue that's left behind. Asher holds up a strip that's already been used.
ASHER: And the one line indicates that it's positive for fentanyl. And five out of six that I've been testing are coming up positive for fentanyl.
HARRIS: Which means the vast majority of what's being sold as heroin, at least on this street corner in the Bronx, contains a drug that's much stronger. Asher hopes knowing that will help users stay safe. If there's fentanyl, maybe they use a little slower. Maybe they use in a safer place. Maybe they don't use at all.
ALEXANDER WALLEY: With fentanyl, it's kind of a new deal. And we need to step up our prevention and treatment game in order to meet that challenge.
HARRIS: Alexander Walley from Boston Medical Center has been tracking the use of these test strips since they were first tried out at a needle exchange in Canada. He thinks about them the same way he thinks about a fire extinguisher or a seatbelt - as a precaution. He's interviewed heroin users and says while some users like fentanyl and some don't...
WALLEY: The majority of people are agnostic because the people that we interview have a daily opioid use disorder. And what they really care about is not being in withdrawal. At the end of the day, I think giving people knowledge about what they're putting in their body is probably a good thing more than a bad thing.
ASHER: Water, Band-Aids, antiseptic...
HARRIS: Back at St. Ann's in the Bronx, Van Asher is taking to social media to convince needle exchanges around the country to join his experiment. He wants to make the case that test strips don't just save lives. They might save money, too. He says, sure, a supply of test strips for a year could cost hundreds of dollars.
ASHER: Sounds like a lot, but when you consider, if I overdose and you call for an ambulance, a dispatcher is getting paid, the ambulance, the two EMTs.
HARRIS: He lists cost after cost.
ASHER: Then there's a triage nurse. Then there's the doctor.
HARRIS: Right now, public health agencies are already spending millions on overdose reversal kits.
ASHER: And I say, yeah, naloxone is great, but a prevented overdose is better.
HARRIS: Asher still needs to prove that's what these test strips do. Before I left, Vincente Estepa, the heroin user I met when I first arrived, explained how hard that will be. Almost all of his heroin has tested positive, but...
ESTEPA: No, it didn't change how I use because at the end of the day, an addict is an addict. And it's stronger and makes me feel the euphoria. So I'm going to go for it.
HARRIS: Using heroin has already taken a lot from Estepa. He's lost his job. He's homeless. But he's still alive. The people running this experiment want to keep it that way. For NPR News, I'm Mary Harris in New York.
(SOUNDBITE OF TOKIMONSTA'S "SMOKE AND MIRRORS")
NPR transcripts are created on a rush deadline by Verb8tm, Inc., an NPR contractor, and produced using a proprietary transcription process developed with NPR. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.