Police departments get new tool to reduce overdose deaths: fentanyl test strips The strips can make users aware that the deadly opioid is present in drugs they are taking so they can take precautions. Share An unidentified man preparing to inject heroin adds some of the diluted drug to a mixing container in this photo taken in New York in 2018. A blue and white fentanyl test strip inserted into the mixing container will indicate whether it contains fentanyl. Associated Press Seven Maine police departments are getting a new tool they hope will reduce the number of fatal drug overdoses in the state.