Chemical fingerprint of alcohol and nicotine consumption in Spanish wastewaters

Abstract

Wastewater provides a fingerprint of a specific population lifestyle. Tracing the right chemical markers in a wastewater sample allows back-calculating the amount of alcohol and tobacco consumed by the people contributing to that sample. This approach, also known as wastewater-based epidemiology (WBE), provides information on substance abuse in a rapid, anonymous and objective way, complementing the information obtained by traditional methods (surveys, medical and criminal indices, etc). WBE has been used in Spain to estimate the consumption of legal and illicit psychoactive substances. While 4 Spanish cities systematically apply the WBE on an annual basis to report the use of illicit drugs to the European Monitoring Centre for Drugs and Drugs Addiction, the WBE has been only occasionally applied in few cities to estimate alcohol and tobacco use. Based on this, the present work aimed at extending the application of the WBE approach in the Spanish territory (14 cities, 17 WWTPs, 13% of the Spanish population) to obtain a more reliable picture on alcohol and tobacco consumption in the country. This work also aimed at evaluating spatial and weekly consumption trends of these legal drugs and compare WBE-derived data with official consumption figures. For this, 24-h composite wastewater samples were collected at the inlet of 17 wastewater treatment plants (WWTPs) during one week in spring 2018, covering approximately 13% of the Spanish population, and urban areas of different size. The samples collected were analysed for urinary biomarkers of alcohol and nicotine (main psychoactive substance of tobacco). Results showed the presence of the three metabolites in all samples analyzed. Spatial variations in alcohol and nicotine consumption were observed among the investigated cities, and in the case of alcohol, also different consumption patterns were observed during the week. Extrapolation of WBE-derived consumption data at national level showed an annual consumption of alcohol lower than that reported by the World Health Organization (WHO). However, in the case of nicotine, consumption obtained by WBE approach was very similar to tobacco.