Wastewater-based epidemiology to assess the occurrence of new psychoactive substances and alcohol consumption in Slovakia.

Consumption of alcohol and new psychoactive substances (NPS) in a population or during special events (music festivals) is usually monitored through individual questionnaires, forensic and toxicological data, and drug seizures. However, consumption estimates have some biases due mostly to the unknown composition of drug pills for NPS and stockpiling for alcohol. The aim of this study was to evaluate for the first time the real use of alcohol and the occurrence of NPS in Slovakia by wastewater-based epidemiology (WBE). Urban wastewater samples were collected from nine Slovak cities over two years (2017-2018) and during three music festivals. The study included about 20% of the Slovak population and 50 000 festival attendees. The urinary alcohol biomarker ethyl sulfate (EtS) and thirty NPS were analyzed by liquid chromatography tandem mass spectrometry (LC - MS/MS). EtS concentrations were used for estimating the per capita alcohol consumption in each city. The average alcohol consumption in the selected cities and festivals in 2017-2018 ranged between 7 and 126 L/day/1000 inhabitants and increased during the weekends and music festivals. Five NPS belonging to the classes of synthetic cathinones (mephedrone, methcathinone, buphedrone and pentedrone) and phenethylamines (25-iP-NBoMe) were found in the low ng/L range. Methcathinone was the most frequently detected NPS, while the highest normalized mass load corresponded to mephedrone (3.1 mg/day/1000 inhabitants). Wastewater-based epidemiology can provide timely information on alcohol consumption and NPS occurrence at the community level that is complementary to epidemiology-based monitoring techniques (e.g. population surveys, police seizures, sales statistics).

Ferrate (VI), Fenton Reaction and Its Modification: An Effective Method of Removing SARS-CoV-2 RNA from Hospital Wastewater.

The outbreak of the coronavirus disease 2019 (COVID-19) raises questions about the effective inactivation of its causative agent, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in medical wastewater by disinfectants. For this reason, our study of wastewater from a selected hospital evaluated several different advanced oxidation methods (Fenton reaction and Fenton-like reaction and ferrate (VI)) capable of effectively removing SARS-CoV-2 RNA. The obtained results of all investigated oxidation processes, such as ferrates, Fenton reaction and its modifications achieved above 90% efficiency in degradation of SARS-CoV-2 RNA in model water. The efficiency of degradation of real SARS-CoV-2 from hospital wastewater declines in following order ferrate (VI) > Fenton reaction > Fenton-like reaction. Similarly, the decrease of chemical oxygen demand compared to effluent was observed. Therefore, all of these methods can be used as a replacement of chlorination at the wastewater effluent, which appeared to be insufficient in SARS-CoV-2 removal (60%), whereas using of ferrates showed efficiency of up to 99%.