In this study, 26 drugs including stimulants, opioids, and antipsychotics were measured in raw wastewater collected from two rest areas and a commercial truck service facility along two interstate highways in Kentucky.
Methamphetamine was discharged significantly higher at the rest areas (108 and 239 mg/d/1000 people at I-24 E and I-24 W, respectively); however, prescription opioids including tramadol, hydrocodone, and morphine as well as temazepam (benzodiazepine) and citalopram (antidepressant) were significantly discharged higher at the commercial truck service facility. Xylazine, a veterinary sedative, was also quantified for the first time in greater than 33% of collected wastewater samples. To the authors’ knowledge, this is the first quantitative study of drugs discharged at rest area facilities along interstate highways. (Publisher abstract provided)