An independent inventor was granted a US Patent (10,591,449) this week for a wearable device to detect illegal narcotics like opiates and cannabis from in the air. The wearable device houses an ionization chamber for ionizing molecules in the air to search for narcotics and then triggers an alarm when narcotics are detected. 

This has potential for use in jobs where cannabis is legal but the sobriety of its employees is critical as well as schools, jails and prisons, and anywhere narcotics shouldn’t be.