Abstract: Urban wastewater surveillance is a crucial tool for public health monitoring and environmental epidemiology. This study
investigates the presence of pharmaceutical compounds and illicit drugs in the wastewater of Patras, Greece, aiming to
identify consumption patterns and health indicators within the population. A plethora of antidepressants, antipsychotics,
antibiotics, antidiabetics, and illicit drugs were detected and quantified using liquid chromatography-tandem mass
spectrometry (LC–MS/MS). Key findings show significant levels of various substances such as venlafaxine, valsartan,
metformin, rosuvastatin, acetaminophen, levetiracetam, gabapentin, cimetidine, caffeine, and nicotine. The results highlight
prevalent public health trends and challenges. Additionally, the detection of illicit drugs such as cocaine (average
169.71 mg/day/1000 people) and methamphetamine (average 13.15 mg/day/1000 people) underscore the ongoing illicit
drug circulation in the city, warranting closer public health monitoring. This research demonstrates the value of Wastewater-
Based Epidemiology (WBE) as an efficient, non-invasive method for tracking population health, lifestyle behaviors,
and environmental contamination, offering critical insights for public health interventions and sustainable wastewater
management strategies. Ultimately, this study reinforces the role of wastewater surveillance as a vital decision-support
tool for protecting public health and shaping effective policy responses.
