Drugs In Wastewater Treatment Plants Research Articles

Adsorption Technologies for the Removal of Cytostatics in Water: A Review

One of the most common treatments for cancer disease requires the administration of cytostatics, which are very effective drugs in the elimination of cancerous cells, but are toxic for healthy tissues. After being administered to patients, they are excreted and frequently reach natural water bodies, due to their poor degradation in wastewater treatment plants (WWTPs), posing a global threat to the environment and human health. The study of proper treatment approaches for the effective removal of these hazardous drugs in WWTPs is thus a topic of concern and of utmost importance to ensure environmental integrity, resilience and sustainability. The aim of this work is to perform a comprehensive review of the application of adsorption-based processes for the treatment of aqueous matrices contaminated with cytostatics, which has never been addressed before. A detailed discussion on the operating conditions, type and concentrations of sorbents used, toxicity of the effluents and other relevant parameters is presented. This paper aims to help identify the most promising sorbents and conditions, the current knowledge gaps, and future challenges/perspectives on adsorption technologies (isolated or coupled with other processes) to tackle the problem of cytostatic fingerprints in water courses. Additionally, information concerning the implementation of these technologies from an environmental and economic (life cycle assessment) perspective is given.

Distribution, fate and removal efficiency of anthelmintic drugs in wastewater treatment plants

The distribution and fate of 19 anthelmintic drugs (ADs) were investigated in two wastewater treatment plants (WWTPs) using different wastewater treatment technologies, including anaerobic-anoxic-aerobic (A2/O) biological process and cyclic activated sludge system (CASS) process. All the 19 ADs were found in the two WWTPs, with concentrations ranging from N.D. to 324.6 ng/L in the influent and from N.D. to 1579.2 ng/L in the effluent. Benzimidazoles were the primary pollutants in the wastewater and suspended particulate matter, accounting for more than half of the total concentration. The concentrations of macrocyclic lactones in the sludge were significantly higher than that of other two media. The ADs removal efficiency of A2/O ranged from −330 % (albendazole sulfoxide) to 100 % (fenbendazole, mebendazole and pyrantel). While the ADs removal efficiency of CASS process ranged from −425 % (albendazole sulfoxide) to 100 % (abamectin, moxidectin and ivermectin). There was no significant difference in the average removal efficiency of the ADs between the two processes (64 % and 63 %, except albendazole sulfoxide). The removal efficiencies of the ADs in the biodegradation stage were better than them in the sedimentation stage. The load per capita of the 19 ADs in two WWTPs ranged from 0 (moxidectin) to 36 μg.d−1.p−1 (albendazole), and the emission in the effluent ranged from 0 (moxidectin) to 163 μg.d−1.p−1 (albendazole sulfoxide). This study provided the first comprehensive data on the occurrence and fate of the 19 ADs and evaluated the removal efficiencies of the 19 ADs in two WWTPs using A2O process and CASS process in the city.

In five wastewater treatment plants in Xinjiang, China: Removal processes for illicit drugs, their occurrence in receiving river waters, and ecological risk assessment

Residues of illicit drugs are frequently detected in wastewater, but data on their removal efficiency by wastewater treatment plants (WWTPs) and the ecological risks to the aquatic environment are lacking in this study. The research evaluates the residues, mass load, drug removal efficiency, and risk assessment of illicit drugs in WWTPs and aquatic environments (lakes) in Xinjiang, China. Initially, the concentration (incidence) and mass load of 10 selected illicit drugs were analyzed through wastewater analysis. The detected substances included methamphetamine (METH), morphine (MOR), 3,4-methylenedioxy methamphetamine (MDMA), methadone (MTD), cocaine (COC), benzoylecgonine (BE), ketamine (KET), and codeine (COD), with concentrations ranging from 0.11 ± 0.01 ng/L (methadone) to 48.26 ± 25.05 ng/L (morphine). Notably, morphine (59.74 ± 5.82 g/day) and methamphetamine (41.81 ± 4.91 g/day) contributed significantly to the WWTPs. Next, the drug removal efficiency by different sewage treatment processes was ranked as follows: Anaerobic-Oxic (A/O) combined Membrane Bio-Reactor (MBR) treatment process > Oxidation ditch treatment process > Anaerobic-Anoxic-Oxic (A2/O) treatment process > Anaerobic-Anoxic-Oxic combined Membrane Bio-Reactor treatment process. Finally, the research reviewed the concentration and toxicity assessments of these substances in the aquatic environment (lakes). The results indicated that Lake1 presented a medium risk level concerning the impact of illicit drugs on the aquatic environment, whereas the other lakes exhibited a low risk level. As a result, it is recommended to conduct long-term monitoring and source analysis of illicit drugs, specifically in Lake1, for further investigation. In conclusion, to enhance the understanding of the effects of illicit drugs on the environment, future research should expand the list of target analytes.

Antineoplastic drugs in urban wastewater: Occurrence, nanofiltration treatment and toxicity screening

Antineoplastic drugs are pharmaceuticals that have been raising concerns among the scientific community due to: (i) their increasing prescription in the fight against the disease of the twentieth century (cancer); (ii) their recalcitrance to conventional wastewater treatments; (iii) their poor environmental biodegradability; and (iv) their potential risk to any eukaryotic organism. This emerges the urgency in finding solutions to mitigate the entrance and accumulation of these hazardous chemicals in the environment. Advanced oxidation processes (AOPs) have been taken into consideration to improve the degradation of antineoplastic drugs in wastewater treatment plants (WWTPs), but the formation of by-products that are more toxic or exhibit a different toxicity profile than the parent drug is frequently reported. This work evaluates the performance of a nanofiltration pilot unit, equipped with a Desal 5DK membrane, in the treatment of real WWTP effluents contaminated (without spiking) with eleven pharmaceuticals, five of which were never studied before. Average removals of 68 ± 23% were achieved for the eleven compounds, with decreasing risks from feed to permeate for aquatic organisms from receiving waterbodies (with the exception of cyclophosphamide, for which a high risk was estimated in the permeate). Aditionally, no significative impact on the growth and germination of three different seeds (Lepidium sativum, Sinapis alba, and Sorghum saccharatum) were determined for permeate matrix in comparison to the control.

Wastewater surveillance for different classes of pharmaceutical drugs: Focus on psychotropic drugs and their metabolites

Wastewater screening analysis for the determination of pharmaceutical drugs belonging to different classes, with particular focus on psychotropic drugs and their metabolites. Wastewater based epidemiology (WBE) recently emerged as an essential and complementary methodology for the evaluation of pharmaceutical and illicit drugs prevalence, by means of quantification of either the parent drugs or their human-specific metabolites in wastewater. Furthermore, water pollution by pharmaceutical drugs is becoming an unavoidable environmental issue of emerging concern, making the water quality monitoring crucial to safeguard its healthy supply to citizens. The most commonly used pharmaceuticals include non-steroidal anti-inflammatory drugs, cardiovascular drugs, anti-depressant and antipsychotic drugs; their Active Pharmaceutical Ingredients (APIs) and some of their metabolites are known to partially survive the conventional process of wastewater treatment. Our study involves a wide screening analysis on wastewater samples entering and leaving various purification plants in the Piedmont region (Italy) to identify the prevalent pharmaceutical drugs and metabolites present in it and so to provide important information about the diffusion of compounds of toxicological interest. A total of 140 target compounds (pharmaceuticals of various therapeutic classes, benzodiazepines and some of their metabolites) were investigated in wastewater samples using only 30 mL aliquots instead of the typical 500 mL reported in the literature. The filtered samples (0.22 μm filters) were extracted and purified by SPE and subsequently 5 μL of the concentrated samples was analyzed with UHPLC-QTOF-HRMS and UHPLC-MS/MS protocols. Thanks to the combined use of the two instruments, a full scan on the exact mass and MS/MS fragmentation data were collected for parent drugs and their main metabolites. 61 out of 119 targeted pharmaceutical drugs and 6 out of 21 targeted metabolites of psychotropic pharmaceutical drugs were detected over a wide concentration interval, ranging from ng/L to μg/L. The highest concentration was 62 μg/L detected for paracetamol. The classes of antidepressants, benzodiazepines, antiepileptics, and antipsychotic required particular attention as they are known to be harmful to aquatic flora and fauna. Among these, citalopram (mean concentration 25.8 ng/mL), lorazepam (mean concentration 32.2 ng/mL), trazodone (mean concentration 17.0 ng/mL) and carbamazepine (mean concentration 134 ng/mL) were detected in both the purifier's affluent and effluent waters. Since some environmental studies have shown that carbamazepine is one of the most frequently detected drugs in wastewater treatment plants, the presence of its main metabolites was explored. In particular, the presence of 10,11-dihydro-10-hydroxycarbamazepine, 10,11-dihydro-10,11-dihydroxycarbamazepine, oxarbamazepine and 10,11-dihydro-10,11-epoxycarbamazepine was revealed. The latter compound (approximately three times more concentrated than carbamazepine) proved to possess antiepileptic properties similar to carbamazepine, possibly producing neurotoxic effects. A reliable wastewater method of analysis involving a low sample volume, its SPE purification, and UHPLC-QTOF-HRMS and UHPLC-MS/MS targeted detection was developed for the simultaneous determination of 119 pharmaceutical drugs and 21 metabolites. The collected data are consistent with those available in the literature and confirm that many pharmaceutical drugs are present in wastewater at a level that pose some risk to flora and fauna, taking into account also the health issues associated with long-term simultaneous exposure to a large number of pharmaceutical products. In conclusion, wastewater surveillance is essential not only to identify the pharmaceutical drugs used in the area but also to monitor the purity of waters. In the future, analyses will be carried out to study the variation in the substances (including NPS) found over time and in the different territories at both intra- and inter-regional levels.

Investigating the biological degradation of the drug β-blocker atenolol from wastewater using the SBR.

Drug compounds are one of the main contributors to the entry of micro-pollutants into the environment, known as a constant threat to environmental stability. Atenolol is a type of beta-blocker extensively used to cure cardiovascular disorders. The residues of this compound have been continuously detected in aquatic environments because it is a polar and poorly biodegradable compound. Thus, removing atenolol from wastewater is essential before discharging into the environment. Biological processes are considered the most important removal process for polar drugs in wastewater treatment plants. Accordingly, for the first time in this study, the SBR performance was investigated in the biodegradation and mineralization of atenolol under different concentrations (50-600mg/L) and hydraulic retention times (48-32h). Based on the results, the time required for the acclimation of biomass to atenolol (C: 50mg/L and the HRT: 48h) was 80 days. The SBR efficiencies under optimum conditions (C: 400mg/L and HRT: 40h) in removing the atenolol and COD were 91% and 87%, respectively. For the first time in this study, one of the main pathways of the atenolol biodegradation was identified. Based on the review and comparison of the results of this study with existing literature showing that the SBR used in this study was able to remove higher concentrations with better efficiencies than other processes. Therefore, it can be concluded that the SBR used in this study could be considered an efficient and promising technique for treating wastewaters containing atenolol and other beta-blocker group drugs.

Detoxifying SARS-CoV-2 antiviral drugs from model and real wastewaters by industrial waste-derived multiphase photocatalysts

The use of antiviral drugs has surged as a result of the COVID-19 pandemic, resulting in higher concentrations of these pharmaceuticals in wastewater. The degradation efficiency of antiviral drugs in wastewater treatment plants has been reported to be too low due to their hydrophilic nature, and an additional procedure is usually necessary to degrade them completely. Photocatalysis is regarded as one of the most effective processes to degrade antiviral drugs. The present study aims at synthesizing multiphase photocatalysts by a simple calcination of industrial waste from ammonium molybdate production (WU photocatalysts) and its combination with WO3 (WW photocatalysts). The X-ray diffraction (XRD) results confirm that the presence of multiple crystalline phases in the synthesized photocatalysts. UV–Vis diffuse reflectance spectra reveal that the synthesized multiphase photocatalysts absorb visible light up to 620 nm. Effects of calcination temperature of industrial waste (550–950 °C) and WO3 content (0–100%) on photocatalytic activity of multiphase photocatalysts (WU and WW) for efficient removal of SARS-CoV-2 antiviral drugs (lopinavir and ritonavir) in model and real wastewaters are studied. The highest k1 value is observed for the photocatalytic removal of ritonavir from model wastewater using WW4 (35.64 ×10–2 min–1). The multiphase photocatalysts exhibit 95% efficiency in the photocatalytic removal of ritonavir within 15 of visible light irradiation. In contrast, 60 min of visible light irradiation is necessary to achieve 95% efficiency in the photocatalytic removal of lopinavir. The ecotoxicity test using zebrafish (Danio rerio) embryos shows no toxicity for photocatalytically treated ritonavir-containing wastewater, and the contrary trend is observed for photocatalytically treated lopinavir-containing wastewater. The synthesized multiphase photocatalysts can be tested and applied for efficient degradation of other SARS-CoV-2 antiviral drugs in wastewater in the future.

Pharmaceutical Pollution: Azole Antifungal Drugs and Resistance of Opportunistic Pathogenic Yeasts in Wastewater and Environmental Water

The occurrence of residual antifungal agents through indiscriminate prophylactic use and inappropriate disposal has been reported in wastewater treatment plants (WWTPs), surface water, and groundwater environments. Opportunistic pathogenic aquatic yeasts develop resistance to commonly used antifungal agents through continued exposure to residual antifungal agents in environmental waters. This poses a major public health concern. The present review attempts to provide a brief description of antifungal drugs, with a focus on the most widely used class of antifungal drugs, the azoles, as emerging contaminants in environmental water. Routes of exposure of azole antifungal drugs in wastewater treatment plants, surface water, and groundwater are discussed. The presence of pathogenic yeasts in environmental water, the associated azole resistance, and the risk of exposure to humans and microbiota are highlighted. Management actions needed to curtail the spread and minimise the risks are also indicated. Further research on the occurrence of antifungal agents in wastewater and environmental water is vital to better understand and mitigate the associated health-related risks.

Removal of antiretroviral drugs stavudine and zidovudine in water under UV254 and UV254/H2O2 processes: Quantum yields, kinetics and ecotoxicology assessment

The concentration of antiretroviral drugs in wastewater treatment plants (WWTP) effluents and surface waters of many countries has increased significantly due to their widespread use for HIV treatment. In this study, the removal of stavudine and zidovudine under UV254 photolysis or UV254/H2O2 was investigated in a microcapillary film (MCF) photoreactor, using minimal water samples quantities. The UV254 quantum yield of zidovudine, (2.357 ± 0.0589)·10−2 mol ein−1 (pH 4.0–8.0), was 28-fold higher that the yield of stavudine (8.34 ± 0.334)·10−4 mol ein−1 (pH 6.0–8.0). The second-order rate constant kOH,iof reaction of hydroxyl radical with the antiretrovirals (UV254/H2O2 process) were determined by kinetics modeling: (9.98 ± 0.68)·108 M−1 s−1 (pH 4.0–8.0) for zidovudine and (2.03 ± 0.18)·109 M−1 s−1 (pH 6.0–8.0) for stavudine. A battery of ecotoxicological tests (i.e. inhibition growth, bioluminescence, mutagenic and genotoxic activity) using bacteria (Aliivibrio fischeri, Salmonella typhimurium), crustacean (Daphnia magna) and algae (Raphidocelis subcapitata) revealed a marked influence of the UV dose on the ecotoxicological activity. The UV254/H2O2 treatment process reduced the ecotoxicological risk associated to direct photolysis of the antiretrovirals aqueous solutions, but required significantly higher UV254 doses (≥2000 mJ cm−2) in comparison to common water UV disinfection processes.

Neuropsychiatric pharmaceuticals and illicit drugs in wastewater treatment plants: a review

Environmental contextNeuropsychiatric pharmaceuticals and illicit drugs in wastewaters are of increasing environmental concern. We compile the recent literature and evaluate the concentrations and profiles of various drugs and their removal efficiencies in wastewater treatment plants. The sewage epidemiology approach, used in the estimation of drug usage in communities, is discussed, and we make recommendations for future research in this area. AbstractNeuropsychiatric pharmaceuticals and illicit drugs encompass a broad range of compounds including opioids, amphetamine-type stimulants, cannabinoids, benzodiazepines, barbiturates, antipsychotics, anaesthetics, anti-epileptics and mood stabilisers, lysergic compounds, sympathomimetic amines and cocaine derivatives. In this article, we review studies on the occurrence and fate of these drugs in wastewater treatment plants. In general, among various drugs studied, the concentrations and detection frequencies of opioids and cocaine derivatives were the highest in wastewaters. The forensic analysis of wastewaters suggests that cocaine and opioids usage has increased. Given the fact that data on drug usage can be used for making regulatory decisions and policies, this review focuses on understanding the sources and environmental dynamics of neuropsychiatric and illicit drugs. There is a pressing need for more research on the magnitude and extent of illicit drug consumption. The ‘sewage epidemiology’ approach, currently applied in the estimation of illicit drug consumption in communities, is reviewed. The field of wastewater research has been advancing in multipronged paths, incorporating concepts in analytical chemistry, organic chemistry, environmental chemistry, biochemistry, sewage engineering, drug epidemiology and statistics. Future prospects with regard to the occurrence and environmental fate of illicit and psychoactive drugs are recommended.

Predicting concentrations of cytostatic drugs in sewage effluents and surface waters of Catalonia (NE Spain)

Cytostatic drugs, used in chemotherapy, are excreted unchanged by urine and feces or modified as metabolites. Elimination of these drugs in wastewater treatment plants (WWTPs) is often incomplete and residues reach surface water. Their presence in the natural environment depends on consumption patterns, excretion fraction and the effectiveness of the wastewater treatment. This study compiled the total consumption of cytostatic drugs in Catalonia (NE Spain) and provides data on the occurrence and risk of anticancer drugs in the aquatic environment by calculating predicted environmental concentrations (PECs). PECs were estimated using publicly available consumption data in the period of 2010–2012, published or calculated excretion values and wastewater elimination rates for a suite of 132 compounds. This allows predicting the range of concentrations in effluent wastewaters and receiving waters. Out of the 132 cytostatics, mycophenolic acid and hydroxycarbamide had a PEC value higher than 10ngL−1. PECs were compared with MECs (measured environmental concentrations) to evaluate the reliability of the estimation. A risk assessment was conducted to determine the potential adverse effects of cytostatics in the environment. All the risk quotients calculated using EC50 in Daphnia magna were below 1, showing no significant risk.

Loadings, trends, comparisons, and fate of achiral and chiral pharmaceuticals in wastewaters from urban tertiary and rural aerated lagoon treatments

A comparison of time-weighted average pharmaceutical concentrations, loadings and enantiomer fractions (EFs) was made among treated wastewater from one rural aerated lagoon and from two urban tertiary wastewater treatment plants (WWTPs) in Alberta, Canada. Passive samplers were deployed directly in treated effluent for nearly continuous monitoring of temporal trends between July 2007 and April 2008. In aerated lagoon effluent, concentrations of some drugs changed over time, with some higher concentrations in winter likely due to reduced attenuation from lower temperatures (e.g., less microbially mediated biotransformation) and reduced photolysis from ice cover over lagoons; however, concentrations of some drugs (e.g. antibiotics) may also be influenced by changing use patterns over the year. Winter loadings to receiving waters for the sum of all drugs were 700 and 400 g/day from the two urban plants, compared with 4 g/day from the rural plant. Per capita loadings were similar amongst all plants. This result indicates that measured loadings, weighted by population served by WWTPs, are a good predictor of other effluent concentrations, even among different treatment types. Temporal changes in chiral drug EFs were observed in the effluent of aerated lagoons, and some differences in EF were found among WWTPs. This result suggests that there may be some variation of microbial biotransformation of drugs in WWTPs among plants and treatment types, and that the latter may be a good predictor of EF for some, but not all drugs.