Wastewater Drug Data 2026: Xylazine, Carfentanil by Region

In July, the White House drug policy office published something it never had before: a report on what's actually dissolved in America's sewage. The Office of National Drug Control Policy paid Biobot Analytics to test wastewater from 101 counties, home to roughly 18 percent of the country, screening for ten drugs that run from fentanyl to veterinary sedatives most people have never heard of. Filter Magazine covered the report and its blind spots, and their reporting is worth your time on the surveillance questions. We're here for the data itself, because underneath a few misleading percentages sits a regional map of the adulterants worth screening for.

What the Sewage Said

Start with the number the report leads with, because it's the one that means the least: ketamine turned up in every county sampled. That sounds dramatic until you remember ketamine is a licensed anesthetic used in hospitals, clinics and veterinary practices everywhere, and wastewater can't tell medical use from anything else. Detection everywhere was the expected result, not a finding.

The findings that matter sit lower in the table. Take xylazine, a veterinary sedative that has been cut into opioids for years, doesn't respond to naloxone, and is linked to serious skin wounds: it showed up in 21 of 23 sampled Northeast counties. Carfentanil, a fentanyl analog potent enough that trace amounts can be fatal, appeared in more than half the counties sampled nationwide. Medetomidine, a newer sedative following xylazine's path into the supply, was already present in 36 of 101 counties. Tianeptine, sold at gas stations as a supplement while acting on opioid receptors, was detected in 75 of the 97 counties that reported it, making it the second-most-widespread substance in the entire report.

The three drugs measured by concentration tell a regional story. Fentanyl peaked nationally in 2023 and has been declining since, reading highest in the West through 2025 and 2026. Methamphetamine has held steady since 2023, also highest out West. Cocaine peaked in the South, where four of the five highest-reading counties sit, three of them in Texas.

What's Showing Up in Your Region

Pick your region below. Every figure is a count of counties rather than a bare percentage, because the report's own denominators shift from drug to drug.

Why This Method Is Worth Taking Seriously

Wastewater testing measures metabolites: norfentanyl for fentanyl, benzoylecgonine for cocaine, the compounds a body produces after a drug has actually been consumed. That's a different kind of evidence than seizure data, which only describes what police happened to intercept, or surveys, which only describe what people are willing to say out loud. Nobody edits their answer on the way to the drain.

Tested at the treatment plant, this method captures a whole community at once, and it can flag an emerging adulterant weeks or months before that compound surfaces in overdose statistics. European cities have run coordinated wastewater programs for years, so the US federal government finally building one is, on balance, good news for anyone trying to watch the supply change in something close to real time.

What Wastewater Testing Can't Do

The report is useful, and it's also a case study in reading limits alongside capabilities, so here are the limits, plainly.

It can't tell you how much of anything is out there. For the seven emerging substances, the report records only detected or not detected, with no concentrations and no scale, not even in the supplementary materials.

It can't separate a prescription from a street sample, and ketamine at every sampled county is the proof. That same ambiguity applies to any substance with a legal medical use.

It can't speak for the places it never tested. Some states are represented by a single county, and the report's own footnote warns that the findings "should not be viewed as representative of the entire state." Its state-level maps color whole states anyway, which is why we chose not to reproduce them here.

It can't ask permission either. Wastewater is legally discarded property, so entire communities get screened without notice or consent, and sewershed-level data could in principle be turned toward law enforcement instead of health. Filter and the researchers it quotes are right to press hard on that.

The last limit is the one that matters most on a Tuesday night: none of this describes the bag in front of you. A regional detection rate tells you about your neighbors' plumbing last month, not about your sample.

What This Means for You

Read the regional data as a checklist, not a verdict. If you're in the Northeast, xylazine was found nearly everywhere the government looked, so screening opioids for it is the reasonable baseline rather than an abundance of caution. Out West, carfentanil appeared in 17 of 28 sampled counties while xylazine stayed comparatively rare. In the South and Midwest, tianeptine is the quiet one: legal to buy, dependence-forming, and now sitting near the top of federal sewage data.

The government's numbers describe what a region already consumed, weeks after the fact, which is exactly the wrong timing for anyone making a decision now. Testing your own sample is how that information arrives before the decision instead of after it. Keep the tiers straight, though: strips screen for one compound at a time, reagents narrow a substance toward a family, and only laboratory analysis confirms what something actually is. A negative result only describes the portion you tested, and no result makes a sample safe.

So the question this report actually raises for you isn't what's in America's wastewater. It's "what's in this?", and that's what the Triple Check is for: screen with strips, identify with multiple reagents, then verify the reaction against lab-verified videos in the free Transparency Harm Reduction App. When a question needs report-grade certainty about one specific sample, mail-in lab analysis exists for exactly that, anonymous and with no personal information required.

People deserve to know what they're taking. It took Washington fifteen years to start agreeing with us, and even now its method only checks after everything has been flushed. You can check first.

Related Resources

• Fentanyl Test Strips: What They Are and How to Use Them
• How to Test for Fentanyl at Home
• Drug Test Strips
• Transparency Harm Reduction App
• Transparency Testing Lab Services
• Our Types of Test Kits

Sources

• ONDCP, "A Powerful Window into Shifting Drug Use Trends" — Wastewater Monitoring Report, July 2026
• Filter Magazine, "White House Shares First Data From Wastewater Drug-Testing Project"

DISCLAIMER

No test result makes a sample safe. Consuming unregulated substances always carries risk, and many factors affect how a result should be interpreted. Detection counts in this article are qualitative, meaning present or not detected, and they say nothing about amounts. Bunk Police test kits are intended to help identify unknown substances for harm reduction purposes only, and Bunk Police assumes no responsibility for the interpretation of results or the use or misuse of this information.