Estimation of community-wide exposure to bisphenol A via water fingerprinting.

Molecular epidemiology in human biomonitoring allows for verification of public exposure to chemical substances. Unfortunately, due to logistical difficulties and high cost, it evaluates only small study groups and as a result does not provide comprehensive large scale community-wide exposure data. Wastewater fingerprinting utilizing metabolic biomarkers of exposure that are excreted collectively by studied populations into urine and ultimately into the community's wastewater, provides a timely alternative to traditional approaches. This study aimed to provide comprehensive spatiotemporal community-wide exposure to bisphenol A (BPA, including BPA intake) using wastewater fingerprinting. Wastewater fingerprinting was undertaken using high resolution mass spectrometry retrospective data mining of characteristic BPA human metabolism marker (bisphenol A sulphate), applied to a large geographical area of 2000 km2 and a population of ~1.5 million served by 5 WWTPs (wastewater treatment plants) accounting for >75% of the overall population in the studied catchment. Community-wide BPA intake was found to be below temporary tolerable daily intake (t-TDI) level of 4 μg kg−1 day−1 set by the European Food Safety Agency (EFSA) suggesting overall low exposure at 3 WWTPs serving residential areas with low industrial/commercial presence. However, at two WWTPs serving communities with higher industrial/commercial presence, higher BPA sulphate loads corresponding to higher (up to 14 times) BPA intakes (exceeding 10 μg kg−1 day−1 at one WWTP and reaching 50 μg kg−1 day−1 at the second WWTP) were observed and they are likely linked with occupational exposure. Characteristic temporal variations of BPA intake were noted in most studied WWTPs with the lowest intake occurring during weekends and the highest during weekdays

New Analytical Framework for Verification of Biomarkers of Exposure to Chemicals Combining Human Biomonitoring and Water Fingerprinting

Molecular epidemiology approaches in human biomonitoring are powerful tools that allow for verification of public exposure to chemical substances. Unfortunately, due to logistical difficulties and high cost, they tend to evaluate small study groups and as a result might not provide comprehensive large scale community-wide exposure data. Urban water fingerprinting provides a timely alternative to traditional approaches. It can revolutionize the human exposure studies as urban water represents collective community-wide exposure. Knowledge of characteristic biomarkers of exposure to specific chemicals is key to the successful application of water fingerprinting. This study aims to introduce a novel conceptual analytical framework for identification of biomarkers of public exposure to chemicals via combined human metabolism and urban water fingerprinting assay. This framework consists of the following steps: (1) in vitro HLM/S9 assay, (2) in vivo pooled urine assay, (3) in vivo wastewater fingerprinting assay, (4) analysis with HR-MSMS, (5) data processing, and (6) selection of biomarkers. The framework was applied and validated for PCMC (4-chloro-<i>m</i>-cresol), household derived antimicrobial agent with no known exposure and human metabolism data. Four new metabolites of PCMC (hydroxylated, sulfated/hydroxylated, sulfated PCMC, and glucuronidated PCMC) were identified using the in vitro HLM/S9 assay. But only one metabolite, sulfated PCMC, was confirmed in wastewater and in urine. Therefore, our study confirms that water fingerprinting is a promising tool for biomarker selection and that in vitro HLM/S9 studies alone, although informative, do not provide high accuracy results. Our work also confirms, for the first time, human internal exposure to PCMC

Assessment of bisphenol-A in the urban water cycle.

The plasticizer bisphenol-A (BPA) is common to municipal wastewaters and can exert toxicity to exposed organisms in the environment. Here BPA concentration at 5 sewage treatment works (STW) and distribution throughout a river catchment in South West UK were investigated. Sampling sites included influent and effluent wastewater (n = 5), river water (n = 7) and digested sludge (n = 2) which were monitored for 7 consecutive days. Findings revealed average BPA loads in influent wastewater at two STWs were 10-37 times greater than the other wastewaters monitored. Concentrations up to ~100 ug L-1 were measured considerably higher than previously reported for municipal wastewaters. Temporal variability throughout the week (i.e., highest concentrations during weekdays) suggests these high concentrations are linked with industrial activity. Despite >90% removal during wastewater treatment, notable concentrations remained in tested effluent (62-892 ng L-1). However, minimal impact on BPA concentrations in river water was observed for any of the effluents. The maximum BPA concentration found in river water was 117 ng L-1 which is considerably lower than the current predicted no effect concentration of 1.6 ug L-1. Nevertheless, analysis of digested sludge from sites which received these elevated BPA levels revealed average concentrations of 4.6 {plusmn} 0.3 and 38.7 {plusmn} 5.4 ug g-1. These sludge BPA concentrations are considerably greater than previously reported and are attributed to the high BPA loading in influent wastewater. A typical sludge application regime to agricultural land would result in a predicted BPA concentration of 297 ng g-1 in soil. Further studies are needed on the toxicological thresholds of exposed terrestrial organisms in amended soils to better assess the environmental risk here

Stereoisomeric profiling of chiral pharmaceutically active compounds in wastewaters and the receiving environment: a catchment-scale and a laboratory study.

Chiral pharmaceutically active compounds (cPACs) are not currently governed by environmental regulation yet are expected to be in the future. As cPACs can exert stereospecific toxicity in the aquatic environment, it is essential to better understand their stereoselective behaviour here. Therefore, this study aims to provide a new perspective towards comprehensive evaluation of cPACs at a river catchment level, including their stereochemistry as a chemical phenomenon driving fate of chiral molecules in the environment. A large spatial and temporal monitoring program was performed in Southwest England. It included 5 sewage treatment works and the receiving waters of the largest river catchment in Southwest England. Simultaneously, lab-scale microcosm studies in simulated activated sludge bioreactors and river water microcosm were performed to evaluate stereoselective degradation of cPACs. A multi-residue enantioselective method allowed the analysis of a total of 18 pairs of enantiomers and 3 single enantiomers in wastewater and river water samples. Our monitoring program revealed: (1) spatial and temporal variations of cPACs in influent wastewaters resulting from different patterns of usage as well as an (2) enantiomeric enrichment of cPACs, likely due to human metabolism, despite their commercialization as racemic mixtures. A similar chiral signature was observed in effluent and receiving waters. Stereoselective degradation was observed in trickling filters (TF) for naproxen, ketoprofen, cetirizine and 10,11-dihydroxy-10-hydroxycarbamazepine, in sequencing batch reactors (SBR) for ifosfamide and in activated sludge (AS) for cetirizine. The extent of enantiomer-specific fate was wastewater treatment dependent in the case of naproxen (TF showed higher stereoselectivity than AS and SBR) and cetirizine (TF and AS showed higher stereoselectivity than SBR) due to differing microbial population. Furthermore, stereoselective degradation of naproxen was highly variable among STWs using similar treatments (TF) and operating in the same region. Microbial stereoselective degradation was also confirmed by both activated and river water simulated microcosm for chloramphenicol, ketoprofen, indoprofen, naproxen and 10,11-dihydroxy-10-hydroxycarbamazepine. Results from our large scale river catchment monitoring study and lab simulated microcosm show wide-ranging implications of enantiomerism of cPACs on environmental risk assessment (ERA). As two enantiomers of the same compound show different biological effects (e.g. toxicity), their non-racemic presence in the environment might lead to inaccurate ERA. This is because current ERA approaches do not require analysis at enantiomeric level

(Fluoro)quinolones and quinolone resistance genes in the aquatic environment: a river catchment perspective.

This study provides an insight into the prevalence of (fluoro)quinolones (FQs) and their specific quinolone qnrS resistance gene in the Avon river catchment area receiving treated wastewater from 5 wastewater treatment plants (WWTPs), serving 1.5 million people and accounting for 75% of inhabitants living in the catchment area in the South West of England. Ofloxacin, ciprofloxacin, nalidixic acid and norfloxacin were found to be ubiquitous with daily loads reaching a few hundred g/day in wastewater influent and tens of g/day in receiving waters. This was in contrast to other FQs analysed: flumequine, nadifloxacin, lomefloxacin, ulifloxacin, prulifloxacin, besifloxacin and moxifloxacin, which were hardly quantified. Enantiomeric profiling revealed that ofloxacin was enriched with the S-(−)-enantiomer, likely deriving from its prescription as the more potent enantiomerically pure levofloxacin, alongside racemic ofloxacin. While ofloxacin's enantiomeric fraction (EF) remained constant, high stereoselectivity was observed in the case of its metabolite ofloxacin-N-oxide. The removal efficiency of quinolones during wastewater treatment at 5 WWTPs utilising either trickling filters (TF) or activated sludge (AS), was compound and wastewater treatment process dependent, with AS providing better efficiency than TF. The qnrS resistance gene was ubiquitous in wastewater. Its removal was WWTP treatment process dependent with TF performing best and resulting in significant removal of the gene (from 28 to 75%). AS underperformed with only 9% removal in the case of activated sludge and actual increase in the gene copy number within sequencing batch reactors (SBRs). Interestingly, the data suggests that higher removal of antibiotics could be linked with high prevalence of the gene (SBR and WWTP E) and vice versa, low removal of antibiotic is correlated with lower prevalence of the gene in wastewater effluent (TF, WWTP B and D). This is especially prominent in the case of ofloxacin and could indicate that AS might be facilitating antimicrobial resistance (AMR) prevalence to higher extent than TF. Wastewater-based epidemiology (WBE) was also applied to monitor any potential misuse (e.g. direct disposal) of FQs in the catchment. In most cases higher use of antibiotics with respect to official statistics (i.e. ciprofloxacin, ofloxacin) was observed, which suggests that FQs management practice require further attention

Measuring biomarkers in wastewater as a new source of epidemiological information:Current state and future perspectives

The information obtained from the chemical analysis of specific human excretion products (biomarkers) in urban wastewater can be used to estimate the exposure or consumption of the population under investigation to a defined substance. A proper biomarker can provide relevant information about lifestyle habits, health and wellbeing, but its selection is not an easy task as it should fulfil several specific requirements in order to be successfully employed. This paper aims to summarize the current knowledge related to the most relevant biomarkers used so far. In addition, some potential wastewater biomarkers that could be used for future applications were evaluated. For this purpose, representative chemical classes have been chosen and grouped in four main categories: (i) those that provide estimates of lifestyle factors and substance use, (ii) those used to estimate the exposure to toxicants present in the environment and food, (iii) those that have the potential to provide information about public health and illness and (iv) those used to estimate the population size. To facilitate the evaluation of the eligibility of a compound as a biomarker, information, when available, on stability in urine and wastewater and pharmacokinetic data (i.e. metabolism and urinary excretion profile) has been reviewed. Finally, several needs and recommendations for future research are proposed.</p

Measuring biomarkers in wastewater as a new source of epidemiological information:Current state and future perspectives

The information obtained from the chemical analysis of specific human excretion products (biomarkers) in urban wastewater can be used to estimate the exposure or consumption of the population under investigation to a defined substance. A proper biomarker can provide relevant information about lifestyle habits, health and wellbeing, but its selection is not an easy task as it should fulfil several specific requirements in order to be successfully employed. This paper aims to summarize the current knowledge related to the most relevant biomarkers used so far. In addition, some potential wastewater biomarkers that could be used for future applications were evaluated. For this purpose, representative chemical classes have been chosen and grouped in four main categories: (i) those that provide estimates of lifestyle factors and substance use, (ii) those used to estimate the exposure to toxicants present in the environment and food, (iii) those that have the potential to provide information about public health and illness and (iv) those used to estimate the population size. To facilitate the evaluation of the eligibility of a compound as a biomarker, information, when available, on stability in urine and wastewater and pharmacokinetic data (i.e. metabolism and urinary excretion profile) has been reviewed. Finally, several needs and recommendations for future research are proposed.This work was supported by the COST Action ES1307 “SCORE – Sewage biomarker analysis for community health assessment”. Emma Gracia-Lor is very grateful to Generalitat Valenciana, Conselleria d'Educació, Investigació, Cultura i Esport (APOSTD/2015, Programa VALi + d) for her post-doctoral contract. Lubertus Bijlsma acknowledges NPS-Euronet (HOME/2014/JDRUG/AG/DRUG/7086), co-funded by the European Union, for his post-doctoral fellowship. Erika Castrignanò, Richard Bade, Juliet Kinyua, Pedram Ramin, Nikolaos I. Rousis, Yeonsuk Ryu would like to thank the SEWPROF MC ITN project, ‘A new paradigm in drug use and human health risk assessment: Sewage profiling at the community level’ [grant agreement 317205] supported by the European Union's Seventh Framework Programme for research, technological development and demonstration for the financial support. Iria González-Mariño extends her gratitude to the Galician Council of Culture, Education and Universities for her postdoctoral contract (Plan Galego de Investigación, Innovación e Crecemento 2011–2015). Foon Yin Lai acknowledges her postdoctoral fellowship from the University of Antwerp. Luigi Lopardo, Axel Rydevik and Barbara Kasprzyk-Hordern would like to acknowledge Leverhulme Trust for funding ‘TOX-EDC, Wastewater profiling for community-wide human exposure assessment from environmental endocrine disrupting chemicals in personal care and consumer products’ (Project No: RPG-2013-297). Frederic Been would like to thank the Swiss National Science Foundation (SNF, P2LAP2_164892) for his post-doctoral grant. This publication reflects the views only of the authors, and the European Commission cannot be held responsible for any use which may be made of the information contained therein