WASHINGTON, USA – The Department of Homeland Security (DHS) Science and Technology Directorate (S&T) released the updated Master Question List (MQL) for Synthetic Opioids, a powerful tool to help federal agencies, emergency responders, and planners crack down on synthetic opioid threats. Backed by the president’s executive order designating fentanyl as a weapon of mass destruction, this scientifically vetted reference guide for the homeland security enterprise delivers the latest critical information on the chemical and physical properties of synthetic opioids, including emerging nitazene compounds.
“The updated MQL is essential for emergency response planners, managers, federal agents, and first responders,” said Pedro Allende, DHS under secretary for science and technology. “By providing the latest science-based guidance, the MQL empowers operators to make informed decisions about detection equipment, improve decontamination protocols, and reduce the impact of synthetic opioids on our communities. I urge all responders to leverage this resource for their operations.”
Synthetic opioids pose serious risks for federal agents and first responders. The risks include inhalation exposure to lingering toxic aerosols of fentanyl and ultra-potent opioids like nitazenes, which are up to ten times stronger than fentanyl.
The guide emphasises the importance of proper personal protective equipment, including NIOSH‑approved respirators and powder-free nitrile gloves. It details operational procedures for exposure management and medical countermeasures, including naloxone and the newly approved nalmefene nasal spray and autoinjector, equipping responders with the tools they need to protect themselves and the public.
The Synthetic Opioids MQL was developed by S&T’s Chemical Security Analysis Center (CSAC). CSAC serves as a national resource for chemical threats and hazards, delivering knowledge products for detection and interdiction, including the Fentanyl Synthesis Quick Reference Guide and the Chemical Agent Reactions Database.
DHS S&T is committed to keeping the MQL current as new knowledge and technologies emerge, so responders and planners always have the latest science to protect themselves and their communities from synthetic opioid threats.

