Is the reliability of wastewater-based epidemiology affected by season? Comparative analysis with pharmaceuticals prescriptions

Wastewater-based epidemiology (WBE) has been already proposed by several authors for estimating the consumption of drugs, mainly the illicit ones. However, not much information is available about the actual reliability of this tool given the absence of comparison with the actual consumption. This work aims to evaluate the reliability of the WBE as a tool for estimating the consumption of pharmaceuticals in urban area. Measured consumption back-calculated with a WBE approach was compared with prescription of pharmaceutical products as "control." Moreover, seasonal influence on (i) pharmaceutical consumption, (ii) load of pharmaceutical products in the sewer system, and (iii) reliability of WBE was evaluated. Ciprofloxacin, sulfamethoxazole, metoprolol, carbamazepine, and citalopram were estimated by WBE with a difference respect to the "control" value lower than 0.2 order of magnitude while only trimethoprim and sotalol exceeded the 0.5 order of magnitude of difference but below the 1 order of magnitude. Sedatives were the best represented by WBE (on average 0.15 order of magnitude of difference compared to prescription data). However, further studies are suggested to fully estimate the influence of the type of APs on the reliability of the WBE. Seasonal patterns were found for the load of ciprofloxacin in the sewer and for the consumption of sulfamethoxazole and trimethoprim by population but seasonal changes did not have a significant impact (p > 0.05) on the reliability of WBE. Despite some gaps remained to optimize the reliability of the tool, WBE can be considered a valid method to estimate the consumption of prescribed drugs from the analysis of the sewer system.

Pharmaceutical and narcotics monitoring in Brno wastewater system and estimation of seasonal effect on the abuse of illicit drugs by a wastewater-based epidemiology approach

The presence of pharmaceuticals (PHA) and narcotics (NAR) in wastewater (WW) has attracting growing interest due to concern for aquatic environment and the possibility to exploit their presence to estimate drug consumption by population. This work aims to (i) quantify PHA and NAR in the WW of the Brno metropolitan area, (ii) determine the effectiveness of the current conventional wastewater treatment plant (WWTP), and (iii) estimate the illicit drug (ID) consumption. 23 PHA and 9 NAR were frequently detected in the untreated WW and studied for their removal. One year monitoring was carried out to highlight a possible seasonal pattern with PHA and NAR load in WW, WWTP effectiveness, and illicit consumption. Results highlighted that the most abundant PHA and NAR were caffeine (73.9 ± 6.9 μg L^-1) and methamphetamine (2.3 ± 0.1 μg L^-1) while oxazepam (0.13 ± 0.05 μg L^-1) and EDDP (0.02 ± 0.01 μg L^-1) were the lowest ones, respectively. Only paracetamol, caffeine, atenolol, ciprofloxacin, amphetamine, cocaine, morphine, and benzoylecgonine exhibited a high biodegradability being removed almost completely (> 90 %). A predominant illicit use of methamphetamine was estimated (17 ± 0.6 doses 1000.inh^-1 d^-1) that might suggest a higher number of consumers than previous official estimation. A lower abuse of cocaine (2.7 ± 0.5 doses 1000.inh^-1 d^-1), amphetamine (2.2 ± 0.3 doses 1000.inh^-1 d^-1), methadone (1.1 ± 0.2 doses 1000.inh^-1 d^-1), heroin (0.9 ± 0.2 doses 1000.inh^-1 d^-1), and MDMA (0.7 ± 0.1 doses 1000.inh^-1 d^-1) was found. A seasonality pattern was highlighted for some PHA and NAR influent load and removal, and, about ID consumption, only for heroin and methadone. These results will be useful for water utilities, to enhance the knowledge about the presence and removal of PHA and NAR, and local and national authorities to evaluate and counteract the problem of ID abuse.

Malt house wastewater treatment with settleable algal-bacterial flocs

This paper deals with biological treatment of malt house wastewater using algal-bacterial flocs. During three months of testing, optimisation of growth conditions and biomass separation leads to maximisation of biomass production, improved flocs settleability and increased pollutant removal efficiency while maintaining low energy demand. At a high food to microorganism ratio (0.16 to 0.29 kg BOD5 kg(-1) TSS d(-1)), the biological oxygen demand (BOD5), chemical oxygen demand (CODCr), total phosphorus (Ptot) and total suspended solids (TSS) removal efficiencies were all higher than 90%. At a food to microorganism ratio of 0.06 kg BOD5 kg(-1) TSS d(-1), BOD5, CODCr, total nitrogen (Ntot), Ptot and TSS removal efficiencies of 99.5%, 97.6%, 91.5%, 97.8% and 98.4%, respectively, were achieved. The study also proved a strong dependence of removal efficiencies on solar radiation. The results suggest the algae-bacteria system is suitable for treatment of similar wastewater in locations with available land and sufficient solar radiation and temperature during the whole year.

A pilot scale comparison of advanced oxidation processes for estrogenic hormone removal from municipal wastewater effluent

This study investigates the oxidation of selected endocrine disrupting compounds (estrone, 17β-estradiol, estriol and 17α-ethinylestradiol) during ozonation and advanced oxidation of biologically treated municipal wastewater effluents in a pilot scale. Selected estrogenic substances were spiked in the treated wastewater at levels ranging from 1.65 to 3.59 μg · L(-1). All estrogens were removed by ozonation by more than 99% at ozone doses ≥1.8 mg · L(-1). At a dose of 4.4 · mg L(-1) ozonation reduced concentrations of estrone, 17β-estradiol, estriol and 17α-ethinylestradiol by 99.8, 99.7, 99.9 and 99.7%, respectively. All tested advanced oxidation processes (AOPs) achieved high removal rates but they were slightly lower compared to ozonation. The lower removal rates for all tested advanced oxidation processes are caused by the presence of naturally occurring hydroxyl radical scavengers - carbonates and bicarbonates.