Estimation of alcohol consumption in the spanish population through the analysis of ethyl sulfate in wastewater

Abstract

Alcohol is one of the most consumed psychoactive substances throughout the world and it is very socially accepted and integrated into everyday life. According to the Global status report on alcohol and health, pure alcohol consumption per person aged 15 or older in Spain was 10.7 liters per year (WHO, 2019). In this study, an alternative and complementary method to those approaches currently used to estimate alcohol consumption by the population is described. This method, wastewater-based epidemiology (WBE), allows back-calculating the alcohol consumption rate in each population from the concentrations of a selected biomarker measured in sewage waters. A total of 28 wastewater treatment plants (WWTPs) were sampled in 22 Spanish cities that belong to 10 autonomous communities. Time-average 24h composite raw wastewater samples were collected from the studied WWTPs on consecutive days along 1 week in the spring and autumn seasons of 2021 and 2022. The EtS was analyzed using an analytical method based on ion- pair liquid chromatography-tandem mass spectrometry (LC-MS/MS). The alcohol consumption estimated from levels of EtS in the analyzed samples ranged from 4.5 and 46 mL/day/inhabitant, with significant differences between cities from different regions and between regions. Also, it is observed that consumption on weekends is higher than on weekdays, with average consumption rates more than 2.2 times higher from Friday to Sunday than from Monday to Thursday. The alcohol consumption investigated in 2021 and 2022 in comparison with previously reported data (in the Spring of 2018) shows the highest consumption values in 2018, the lowest in 2021 (when the COVID-19 pandemic restrictions were still important), and a recovery to intermediate values in 2022. WBE-derived estimates of alcohol consumption were comparable to previous studies and the values reported by the Spanish Ministry of Health, Consumption and Social Welfare in collaboration with the National Institute of Statistic (INE). In conclusion, the study finds that the WBE approach is a very useful tool, complementary to traditional methods, to estimate the consumption of alcohol in a population.