The U.S. Customs and Border Protection Agency is evaluating technology capable of detecting illegal substances in the air without any physical contact. This device aims to screen border objects quickly to combat the trafficking of drugs like fentanyl, a major contributor to the U.S. opioid crisis.

Detecting drugs and explosive compounds poses a challenge due to their release of relatively few molecules into the already vapor-laden air. To tackle this issue, the U.S. Pacific Northwest National Laboratory (PNNL) has spent over a decade developing an advanced system known as VaporID. This system can accurately identify certain substances from distances of 0.6 to 2.4 meters with sensitivity levels as low as a quarter of a part per trillion. This level of precision equates to locating a single coin in a stack of pennies that is 17 million times taller than Mount Everest.

Government scientists improved sensitivity by allowing molecules more time to create detectable chemical reactions through random collisions with other molecules. While most devices used for identifying unknown substances react to molecules within a few milliseconds, Robert Ewing at PNNL notes that “we created an atmospheric flow tube. This expands the reaction time to 2-3 seconds, which boosts sensitivity by three orders of magnitude.”

The technology has been integrated into a compact, microwave-sized device weighing 18 kilograms. Developed by California-based company Bayspec, this miniaturized machine is still less sensitive than the larger, fridge-sized version used at the PNNL lab. However, Bayspec’s CEO, William Yang, claims it is “more accurate and sensitive than a dog.”

In October 2024, researchers from Bayspec and PNNL tested the portable device at a Customs and Border Protection (CBP) facility in Nogales, Arizona. During separate trials, researchers swiped the surfaces of seized tablets and heated the swabs to generate steam for detection. “Both techniques yielded strong and reliable results,” says Christian Thoma of Bayspec.

The prototype is still under evaluation and requires further scientific data analysis, according to a CBP spokesperson.

Alex Krotulski of the Center for Forensic Research and Education, a nonprofit in Pennsylvania, comments, “We’ve encountered many devices that promise too much, so we’re cautious until they demonstrate efficacy through extensive research and assessments.”

There are already existing portable methods, such as x-rays, to uncover hidden drugs. Richard Crocombe, an independent consultant in Massachusetts, considers the new tool “another valuable addition to the arsenal,” but cautions that it “doesn’t fulfill all requirements.” A CBP spokesman acknowledged that while it could expedite drug testing in field labs, new devices may still require analysis by trained chemists.

These screening methods are also prone to false positives; “drug residues can be quite ubiquitous,” states Joseph Palamar at New York University. A related study indicated that most U.S. banknotes are contaminated. “If you happen to be near someone using fentanyl, the device could react positively based on trace amounts they might have on clothing or shoes. This raises concerns about innocent individuals being wrongly detained,” warns Chelsea Schauber at UCLA.

Preventing drugs from entering the country is just one piece of the larger strategy needed to address the opioid crisis, according to Schauber. This also calls for robust public health agencies, better access to healthcare, and comprehensive treatment options. She emphasizes that these resources are currently being diminished under the Trump administration. “To save lives, we need evidence-based, effective treatments that are more accessible than illegal drugs,” Schober concludes.