The first wastewater-based epidemiology study for alcohol monitoring in Cyprus: Temporal and spatial consumption trends from a one-year study.

Recent studies conducted globally have identified a rising trend in alcohol consumption during the last years, generating a great concern, due to the negative consequences on human health and the broader effects on society. Monitoring of ethyl sulphate (EtS) by applying wastewater epidemiology (WBE) has been proven to be an effective technique for the assessment of alcohol use within a community. This work reports the results of a WBE-based study, conducted for the first time in the Republic of Cyprus, on alcohol consumption, throughout a one-year systematic monitoring. Daily influent wastewater samples from two wastewater treatment plants (WWTPs), one serving part of the capital city and one a coastal touristic area, were collected every three days for one year, and EtS was determined by means of liquid chromatography tandem mass spectrometry. The analysis revealed a relatively stable mean monthly alcohol consumption in the capital area, with daily consumption ranging from 0.31 to 10.60 mL/day/inh. In the coastal area, significant variations in alcohol consumption were observed, with tourist activity during the summer months being associated with nearly a tenfold increase in alcohol use compared to the winter months. Furthermore, four weekly campaigns were conducted for the determination of five stimulant illicit drugs. The results indicated a statistically significant association between alcohol and some stimulants, namely methamphetamine, MDMA, and ketamine. While this association does not imply direct causation or co-consumption, it highlights potential patterns of concurrent presence in wastewater.