Fentanyl
Cities measured
87
Detected in
70 / 87
Highest
0.00062 μg/L — Los Angeles
Overview
Fentanyl is a synthetic opioid ~100× more potent than morphine. Medical fentanyl (patches, anesthesia) enters water via excretion. Illicit fentanyl — driving catastrophic overdose mortality in North America — is now appearing in European drug markets.
Health Relevance
At environmental concentrations, no pharmacological effect via water. The crisis is entirely related to direct consumption — a 2 mg dose can be fatal.
Regulatory Limits
Drinking Water Directive 2020/2184
No regulatory limit.
Controversy & Contested Science
Fentanyl causes ~70,000+ overdose deaths annually in the US since 2017. In Europe, EMCDDA reports increasing fentanyl detections in wastewater, particularly in Belgium and Estonia. Illicitly manufactured fentanyl analogues (acetylfentanyl, carfentanil, nitazenes) are emerging in heroin supply chains — undetectable without chemical testing, lethal at microgram doses. Wastewater surveillance is among the first systems to detect this geographic spread, providing weeks of advance warning before clinical overdose data captures the same trend.