A new combination of opioids, known as “Gray Death,” is being blamed for deaths in Alabama, Georgia and Ohio, the Associated Press reports. The combination includes heroin, fentanyl, carfentanil and a synthetic opioid called U-47700.

“Gray death is one of the scariest combinations that I have ever seen in nearly 20 years of forensic chemistry drug analysis,” said Deneen Kilcrease, manager of the chemistry section at the Georgia Bureau of Investigation. Kilcrease said people using the drug are not aware of its ingredients or their concentrations. Simply touching the powder can put a person at risk, she added.

Gray death looks like concrete mix. It varies in consistency from a hard, chunky material to a fine powder, the article notes. It is much more potent than heroin, according to the Gulf Coast High Intensity Drug Trafficking Area. People use the drug by injecting, swallowing, smoking or snorting it.