Banknotes as a Source of Drug and Pharmaceutical Contamination of the Population

This study investigates the potential contamination of cash register employees in the Slovak Republic with 148 selected pharmaceuticals, illicit drugs, and their metabolites. Of these, 42 substances were detected, and it was found that the target group-cashiers-regularly handle large volumes of banknotes, increasing their exposure to contaminants compared to the general population. This study revealed that commonly prescribed and over-the-counter medications significantly contribute to the contamination of cash registers. This study found that cashiers exhibited notably higher detection rates of antibiotics, including penicillin-V (2×), azithromycin (23×), and erythromycin (up to 64×), than the general population. Additionally, there was an alarming increase in illegal substances, with methamphetamine levels rising fivefold and cocaine up to fifteenfold. This study highlights a broader environmental concern, suggesting that routine handling of contaminated banknotes may lead to the transfer of micropollutants. Furthermore, personal hygiene practices, particularly handwashing, could play a role in introducing pharmaceuticals and narcotics into wastewater, potentially contributing several milligrams of contaminants daily.