"Etazene, safer than heroin and fentanyl": Non-fentanyl novel synthetic opioid listings on one darknet market.  Lamy FR, Daniulaityte R, Barratt MJ, Lokala U, Sheth A, Carlson RG.  Drug Alcohol Depend. 2021 May 31;225:108790. doi: 10.1...

The rise of illicit fentanyls, stimulants and the fourth wave of the opioid overdose  crisis,  Ciccarone, Daniel  Current Opinion in Psychiatry: July 2021 - Volume 34 - Issue 4 - p 344-350 doi: 10.1097/YCO.0000000000000717  ...

CDC. Opioids https://www.cdc.gov/opioids

USA. New High Potency Synthetic Opioid N-Pyrrolidino Etonitazene (Etonitazepyne) Linked to Overdoses Across United States (CFSRE - Center for Forensic Science Research & Education, USA, Juni 2021) https://www.npsdiscovery.org/wp-content/uplo...

Does the preparation for intravenous administration affect the composition of heroin injections? A controlled laboratory study.  Andersen, J. M., Bogen, I. L., Karinen, R., Brochmann, G. W., Mørland, J., Vindenes, V., and Boix, F. (2021) Add...

Commentary - Heroin purity and adulteration: an updated snapshot from the Italian Early Warning System.  Tittarelli R, di Luca NM, Pacifici R, Pichini S, Del Rio A, Busardò FP.  Eur Rev Med Pharmacol Sci. 2020 Apr;24(8):4461-4466. doi:...