Wastewater treatment plants as chemical observatories to forecast ecological and human health risks of manmade chemicals

Prevalence rates of neurodegenerative diseases versus human exposures to heavy metals across the United States

Novel means are needed to identify individuals and subpopulations susceptible to and afflicted by neurodegenerative diseases (NDDs). This study aimed to utilize geographic distribution of heavy metal sources and sinks to investigate a potential human health risk of developing NDDs. Known or hypothesized environmental factors driving disease prevalence of Alzheimer's Disease (AD), Parkinson's Disease (PD), and amyotrophic lateral sclerosis (ALS) are heavy metals, including arsenic (As), cadmium (Cd), manganese (Mn) and mercury (Hg). Lead (Pb) has been associated with AD and ALS. Analyzable mediums of human exposure to heavy metals (i.e., toxic metals and metalloids), or proxies thereof, include infant blood, topsoil, sewage sludge, and well water. U.S. concentrations of heavy metals in topsoil, sewage sludge, well water, and infant blood were mapped and compared to prevalence rates of major NDDs. Data from federal and state agencies (i.e., CDC, EPA, and the US Geological Survey) on heavy metal concentrations, age distribution, and NDD prevalence rates were geographically represented and statistically analyzed to quantify possible correlations. Aside from an expected significant association between NDD prevalence and age (p < 0.0001), we found significant associations between the prevalence of the sum of three major NDDs with: Pb in topsoil (p = 0.0433); Cd (p < 0.0001) and Pb (p < 0.0001) in sewage sludge; Pb in infant blood (p < 0.0001). Concentrations in sewage sludge of Cd and Pb were significantly correlated with NDD prevalence rates with an odds ratio of 2.91 (2.04, 4.225 95%CI) and 4.084 (3.14, 5.312 95%CI), respectively. The presence of toxic metals in the U.S. environment in multiple matrices, including sewage sludge, was found to be significantly associated with NDD prevalence. This is the first use of sewage sludge as an environmental proxy matrix to infer risk of developing NDDs.

Preconceptional and in utero exposure of sheep to a real-life environmental chemical mixture disrupts key markers of energy metabolism in male offspring

Over recent decades, an extensive array of anthropogenic chemicals have entered the environment and have been implicated in the increased incidence of an array of diseases, including metabolic syndrome. The ubiquitous presence of these environmental chemicals (ECs) necessitates the use of real-life exposure models to the assess cumulative risk burden to metabolic health. Sheep that graze on biosolids-treated pastures are exposed to a real-life mixture of ECs such as phthalates, per- and polyfluoroalkyl substances, heavy metals, pharmaceuticals, pesticides, and metabolites thereof, and this EC exposure can result in metabolic disorders in their offspring. Using this model, we evaluated the effects of gestational exposure to a complex EC mixture on plasma triglyceride (TG) concentrations and metabolic and epigenetic regulatory genes in tissues key to energy regulation and storage, including the hypothalamus, liver, and adipose depots of 11-month-old male offspring. Our results demonstrated a binary effect of EC exposure on gene expression particularly in the hypothalamus. Principal component analysis revealed two subsets (B-S1 [n = 6] and B-S2 [n = 4]) within the biosolids group (B, n = 10), relative to the controls (C, n = 11). Changes in body weight, TG levels, and in gene expression in the hypothalamus, and visceral and subcutaneous fat were apparent between biosolid and control and the two subgroups of biosolids animals. These findings demonstrate that gestational exposure to an EC mixture results in differential regulation of metabolic processes in adult male offspring. Binary effects on hypothalamic gene expression and altered expression of lipid metabolism genes in visceral and subcutaneous fat, coupled with phenotypic outcomes, point to differences in individual susceptibility to EC exposure that could predispose vulnerable individuals to later metabolic dysfunction.

Tourmaline guiding the electric field and dechlorination pathway of 2,3-dichlorophenol by Desulfitobacterium hafniense

The dehalogenation of organohalides has been a research hotspot in bioremediation field; however, the influence of tourmaline, a natural ore that can generate spontaneous electric field, on organohalide-respiring bacteria (OHRB) and their dechlorination process is not well known. In this study, the effect and mechanism of tourmaline on the reductive dechlorination of 2,3-dichlorophenol (2,3-DCP) by Desulfitobacterium hafniense DCB-2T were explored. The characterization results confirmed that tourmaline had good stability and the optimal dosage of tourmaline was 2.5 g/L, which shortened the total time required for dechlorination reaction to 72 hr. Besides, tourmaline amendment also increased the proportion of 2-chlorophenol (2-CP) from 18% to 30% of end products, while that of 3-CP decreased correspondingly. The theoretical calculations showed that the bond charge of the ortho-substituted chlorine declined from -0.179 to -0.067, and that of meta-substituted chlorine increased from -0.111 to -0.129, which indicated that the spontaneous electric field of tourmaline affected the charge distribution of 2,3-DCP and was more conducive to the generation of 2-CP. Overall, tourmaline with the spontaneous electric field affected the reductive dechlorination pathway of Desulfitobacterium,and the tourmaline-OHRB combining system might serve as a novel strategy for the bioremediation of environments polluted with chlorinated phenols.

Wastewater sequencing reveals community and variant dynamics of the collective human virome

Wastewater is a discarded human by-product, but its analysis may help us understand the health of populations. Epidemiologists first analyzed wastewater to track outbreaks of poliovirus decades ago, but so-called wastewater-based epidemiology was reinvigorated to monitor SARS-CoV-2 levels while bypassing the difficulties and pit falls of individual testing. Current approaches overlook the activity of most human viruses and preclude a deeper understanding of human virome community dynamics. Here, we conduct a comprehensive sequencing-based analysis of 363 longitudinal wastewater samples from ten distinct sites in two major cities. Critical to detection is the use of a viral probe capture set targeting thousands of viral species or variants. Over 450 distinct pathogenic viruses from 28 viral families are observed, most of which have never been detected in such samples. Sequencing reads of established pathogens and emerging viruses correlate to clinical data sets of SARS-CoV-2, influenza virus, and monkeypox viruses, outlining the public health utility of this approach. Viral communities are tightly organized by space and time. Finally, the most abundant human viruses yield sequence variant information consistent with regional spread and evolution. We reveal the viral landscape of human wastewater and its potential to improve our understanding of outbreaks, transmission, and its effects on overall population health.

Ecopharmacology: Knowledge, Attitude, and Medication Disposal Practice Among Pharmacy Students

Background

Ecopharmacology, as a form of drug management for the environment, focuses on the impact of drugs on the environment. Pharmacists, and by extension pharmacy students, are expected to play an important role in ecopharmacology. Therefore, this study was conducted to determine the knowledge and attitude towards ecopharmacology and the practice of disposal of leftover or expired medicines among pharmacy students.

Methods

This was a descriptive cross-sectional study among pharmacy students in Northwestern Ethiopia. The study took place from May 1 to June 15, 2023. A self-administered questionnaire was used for data collection.

Results

Four hundred and forty-five students were included in the study. Only 91 (20%) of the students were aware of the term ecopharmacology, 27% knew that excretion from the human or animal body is the major route by which pharmaceutical agents enter the environment, and 42% were aware of the risk of increased antimicrobial resistance due to antibiotic residues in the environment. In addition, only 27% of respondents reported receiving information about the disposal of pharmaceuticals. The most common method of disposing of medications was throwing them away in household trash (61.8%).

Conclusion

Our results suggest that while most pharmacy students in Ethiopia have a positive attitude toward ecopharmacology, they do not know enough about ecopharmacology and dispose of their medicines poorly. More uniform education in ecopharmacology and pharmaceutical pollution might be warranted in the pharmacy curriculum.

Wastewater surveillance facilitates climate change-resilient pathogen monitoring

Traditional disease surveillance systems are ill-equipped to handle climate change-driven shifts in pathogen dynamics. If paired with wastewater surveillance, a cost-effective and scalable approach for generating high-resolution health data, such next-generation systems can enable effective resource allocation and delivery of targeted interventions.

Sexually dimorphic impact of preconceptional and gestational exposure to a real-life environmental chemical mixture (biosolids) on offspring growth dynamics and puberty in sheep

Humans are ubiquitously exposed to complex mixtures of environmental chemicals (ECs). This study characterised changes in post-natal and peripubertal growth, and the activation of the reproductive axis, in male and female offspring of sheep exposed to a translationally relevant EC mixture (in biosolids), during pregnancy. Birthweight in both sexes was unaffected by gestational biosolids exposure. In contrast to females (unaffected), bodyweight in biosolids males was significantly lower than controls across the peripubertal period, however, they exhibited catch-up growth eventually surpassing controls. Despite weighing less, testosterone concentrations were elevated earlier, indicative of early puberty in the biosolids males. This contrasted with females in which the mean date of puberty (first progesterone cycle) was delayed. These results demonstrate that developmental EC-mixture exposure has sexually dimorphic effects on growth, puberty and the relationship between body size and puberty. Such programmed metabolic/reproductive effects could have significant impacts on human health and wellbeing.

Developmental exposure to a real-life environmental chemical mixture alters testicular transcription factor expression in neonatal and pre-pubertal rams, with morphological changes persisting into adulthood

Environmental chemical (EC) exposure may be impacting male reproductive health. The translationally relevant biosolids treated pasture (BTP) sheep model was used to investigate gestational low-level EC mixture exposure on the testes of F1 male offspring. Adult rams from ewes exposed to BTP 1 month before and throughout pregnancy had more seminiferous tubules with degeneration and depletion of elongating spermatids, indicating possible "recovery" from previously reported testicular dysgenesis syndrome-like phenotype in neonatal and pre-pubertal BTP lambs. Expression of transcription factors CREB1 (neonatal) and BCL11A and FOXP2 (pre-pubertal) were significantly higher in the BTP exposed testes, with no changes seen in adults. Increased CREB1, which is crucial for testes development and regulation of steroidogenic enzymes, could be an adaptive response to gestational EC exposure to facilitate the phenotypic recovery. Overall, this demonstrates that testicular effects from gestational exposure to low-level mixtures of ECs can last into adulthood, potentially impacting fertility and fecundity.

Systematic scoping review evaluating the potential of wastewater-based epidemiology for monitoring cardiovascular disease and cancer

Cardiovascular disease (CVD) and cancer are collectively responsible for tens of millions of global deaths each year. These rates are projected to intensify as the COVID-19 pandemic has caused delays in individualized diagnostics, or exacerbated prevalence due to Post Acute Coronavirus (COVID-19) Syndrome. Wastewater-based epidemiology (WBE) has successfully been employed as a useful tool for generating population-level health assessments, and was examined here in this systematic scoping literature review to (i) identify endogenous human biomarkers reported to indicate CVD or cancer in clinical practice, (ii) assess specificity to the indicated diseases, (iii) evaluate the utility for estimating population-level disease prevalence in community wastewater, and (iv) contextualize the obtained information for monitoring CVD and cancer presence via WBE. A total of 48 peer-reviewed papers were critically examined identifying five urinary protein biomarkers: cardiac troponin I (cTnI) (heart attack/heart failure), cystatin C (atherosclerosis), normetanephrine (tumor presence), α-fetoprotein (prostate and liver cancer), and microtubule assisted serine/threonine kinase 4 (MAST4) (breast cancer). Next, urinary excretion information was utilized to predict biomarker concentrations extant in community wastewater, resulting in average healthy concentrations ranging from 0.02 to 1159 ng/L, and disease-indicating thresholds from 0.16 to 3041 ng/L. Finally, estimating prevalence-adjusted wastewater measurements was explored in order to assess community-level CVD and cancer presence utilizing U.S. reported prevalence rates. Results obtained suggest that WBE can serve as a viable tool in support of current methods for CVD and cancer assessment to reduce morbidities and mortalities worldwide.

Critical review on phytoremediation of polyfluoroalkyl substances from environmental matrices: Need for global concern

Poly- and perfluoroalkyl substances (PFAS) are a class of emerging organic contaminants that are impervious to standard physicochemical treatments. The widespread use of PFAS poses serious environmental issues. PFAS pollution of soils and water has become a significant issue due to the harmful effects of these chemicals both on the environment and public health. Owing to their complex chemical structures and interaction with soil and water, PFAS are difficult to remove from the environment. Traditional soil remediation procedures have not been successful in reducing or removing them from the environment. Therefore, this review focuses on new phytoremediation techniques for PFAS contamination of soils and water. The bioaccumulation and dispersion of PFAS inside plant compartments has shown great potential for phytoremediation, which is a promising and unique technology that is realistic, cost-effective, and may be employed as a wide scale in situ remediation strategy.

Determining Toxic Potencies of Water-Soluble Contaminants in Wastewater Influents and Effluent Using Gene Expression Profiling in C. elegans as a Bioanalytical Tool

With chemical analysis, it is impossible to qualify and quantify the toxic potency of especially hydrophilic bioactive contaminants. In this study, we applied the nematode C. elegans as a model organism for detecting the toxic potency of whole influent wastewater samples. Gene expression in the nematode was used as bioanalytical tool to reveal the presence, type and potency of molecular pathways induced by 24-h exposure to wastewater from a hospital (H), nursing home (N), community (C), and influent (I) and treated effluent (E) from a local wastewater treatment plant. Exposure to influent water significantly altered expression of 464 genes, while only two genes were differentially expressed in nematodes treated with effluent. This indicates a significant decrease in bioactive pollutant-load after wastewater treatment. Surface water receiving the effluent did not induce any genes in exposed nematodes. A subset of 209 genes was differentially expressed in all untreated wastewaters, including cytochromes P450 and C-type lectins related to the nematode's xenobiotic metabolism and immune response, respectively. Different subsets of genes responded to particular waste streams making them candidates to fingerprint-specific wastewater sources. This study shows that gene expression profiling in C. elegans can be used for mechanism-based identification of hydrophilic bioactive compounds and fingerprinting of specific wastewaters. More comprehensive than with chemical analysis, it can demonstrate the effective overall removal of bioactive compounds through wastewater treatment. This bioanalytical tool can also be applied in the process of identification of the bioactive compounds via a process of toxicity identification evaluation.

Developmental exposure to real-life environmental chemical mixture programs a testicular dysgenesis syndrome-like phenotype in prepubertal lambs

Current declines in male reproductive health may, in part, be driven by anthropogenic environmental chemical (EC) exposure. Using a biosolids treated pasture (BTP) sheep model, this study examined the effects of gestational exposure to a translationally relevant EC mixture. Testes of 8-week-old ram lambs from mothers exposed to BTP during pregnancy contained fewer germ cells and had a greater proportion of Sertoli-cell-only seminiferous tubules. This concurs with previous published data from fetuses and neonatal lambs from mothers exposed to BTP. Comparison between the testicular transcriptome of biosolids lambs and human testicular dysgenesis syndrome (TDS) patients indicated common changes in genes involved in apoptotic and mTOR signalling. Gene expression data and immunohistochemistry indicated increased HIF1α activation and nuclear localisation in Leydig cells of BTP exposed animals. As HIF1α is reported to disrupt testosterone synthesis, these results provide a potential mechanism for the pathogenesis of this testicular phenotype, and TDS in humans.

Comparative meta-analysis of organic contaminants in sewage sludge from the United States and China

Characterizing the occurrence of organic contaminants (OCs) of environmental health concern in municipal sewage sludges is essential for safe handling and disposal of these abundant materials. This meta-analysis aimed to (i) summarize the extent of studies performed on the chemical composition of sewage sludges from China and the U.S., the world's two largest chemical producers, (ii) identify chemical groups of priority concern, (iii) quantitatively compare chemical abundance in sludge between nations, (iv) determine longitudinal contaminant accumulation trends in sludge, and (v) identify data gaps with regard to OC concentrations in sludge. A literature search was conducted on concentrations of OCs in U.S. sludges produced during treatment of domestic and industrial wastewater and compared statistically to contaminant levels in Chinese sludge abstracted from a recently established database. Longitudinal trends of OC occurrence were interpreted in the context of national chemical production, usage statistics, and regulations. A total of 105 studies on OCs in U.S. sewage sludge were found, while a total of 159 had been found in China. Among 1175 OCs monitored for, 23% of all analytes had been monitored in both countries (n = 269), 41% (n = 480) in China only, and the remaining 36% (n = 426) in the U.S. only. On average, concentrations of OCs were 4.0 times higher in U.S. than in Chinese sewage sludge, with the highest detection being observed for alkylphenol ethoxylates. Data from a new binational database on toxic OCs in sewage sludges suggest and reiterates the need for additional chemical monitoring in both countries, risk assessments for emerging OCs contained in sludges destined for application on land, and stronger enforcement of sludge disposal restrictions in China, where as much as 40% of sludge is currently being dumped improperly.

Opportunities and limits of wastewater-based epidemiology for tracking global health and attainment of UN sustainable development goals

Wastewater-based epidemiology (WBE) emerged as a powerful, actionable health management tool during the COVID-19 pandemic. Hypothesizing future uses, we explored its potential for real-time, tracking of progress in attaining United Nations Sustainable Development Goals (SDGs) globally as a non-expensive method using existing infrastructure. We inventoried (i) literature-documented sewerage infrastructure, (ii) demographics of populations served, and (iii) WBE markers informative of 9 SDGs. Among the 17 different sustainable development goals listed by the UN 2030 agenda, more than half of these may be monitored by using WBE monitoring at centralized treatment infrastructure as tabulated in this study. Driven mainly by COVID-19, WBE currently is practiced in at least 55 countries, reaching about 300 million people. Expansion of WBE to 109,000 + treatment plants inventoried in 129 countries would increase global coverage 9-fold to 34.7% or 2.7 billion, leaving out 5 billion people not served by centralized sewerage systems. Associations between population demographics and present-day infrastructure are explored, and geospatial regions particularly vulnerable to infectious disease outbreaks are identified. The results suggest that difference in the differential outcomes in well-being is an outcome of the sanitation infrastructure inequalities and lack of sanitation infrastructure creates doubly disadvantaged populations at risk of poor hygiene and cut off from the early-warning benefits of conventional WBE. This is the first study to explore the feasibility and potential barriers to the use of WBE for tracking the attainment of SDGs globally with at least 9 out of 17 SDGs.

Assessment of leachable and persistent dissolved organic carbon in sludges and biosolids from municipal wastewater treatment plants

Environmental regulation of organic pollutants has not kept pace with the growth in the number and diversity of legacy and emerging organic substances now in use. Simpler and cheaper tools and methodologies are needed to quickly assess the organic pollutant risks in waste materials applied to land such as municipal wastewater treatment sludges and biosolids. This study attempts to provide these, using an approach that consists of chemical leaching and analysis of dissolved organic carbon and determination of its biodegradability by measuring persistent dissolved organic carbon. Primary and secondary sludges, dewatered sludge cake, and anaerobically and thermally treated biosolids obtained from various types of municipal wastewater treatment plants were used in the study. The study found little variability in the levels of dissolved organic carbon leached from primary sludges obtained from different municipal wastewater treatment plants but found significant differences for secondary sludges based on levels of nitrification at the municipal wastewater treatment plants. As predicted treated biosolids leached less dissolved organic carbon than untreated dry sludges but had relatively higher proportions of persistent or poorly biodegradable dissolved organic carbon. Across all tested sludges and biosolids persistent dissolved organic carbon ranged from 14 to 39%, with biosolids that have undergone anaerobic digestion and thermal treatment more likely to contain greater relative proportion of persistent dissolved organic carbon than untreated sludges. The approach presented in this study will be useful in assessing the effectiveness of current and widely employed sludge treatment methods in reducing persistent organic pollutants in biosolids disposed on land.

PFAS fate and destruction mechanisms during thermal treatment: a comprehensive review

Per- and polyfluoroalkyl substances (PFAS) are persistent chemicals and have been detected throughout the environment. Thermal treatment is the most common remediation approach for PFAS-contaminated solid wastes. Although various thermal treatment techniques have demonstrated the potential to destruct PFAS, the fate of PFAS, removal efficacy, potential emissions, and the formation of incomplete combustion products during thermal treatment are little known. This study provides a critical review on the behavior of PFAS based on different types of thermal treatment technologies with various PFAS-impacted environmental medias that include water, soil, sewage sludge, pure PFAS materials, and other PFAS-containing wastes. Different extents of PFAS thermal destruction are observed across various thermal treatment techniques and operating conditions. PFAS removal and destruction efficiencies rely heavily on PFAS structures, the complex combustion chemistry, the presence or absence of oxygen, temperature, and other operational conditions. This review also covers proposed PFAS thermal destruction mechanisms. Different thermal destruction mechanisms for perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS), and other PFAS are reviewed and compared. The majority of studies about PFAS thermal destruction mechanisms were focused on a specific list of PFAS and based mostly on the pyrolysis treatment. The basic pathway for PFAS destruction during pyrolysis is hydrodefluorination, which could be largely influenced by the alkaline condition. Future field-scale research that involves the characterization of PFAS destruction products and incomplete combustion products is needed to address public concerns and better emission control.

The Potential of Sewage Sludge to Predict and Evaluate the Human Chemical Exposome

Chemicals are part of our daily lives, and we are exposed to numerous chemicals through multiple pathways. Relevant scientific evidence contributing to the regulation of hazardous chemicals require a holistic approach to assess simultaneous exposure to multiple compounds. Biomonitoring provides an accurate estimation of exposure to chemicals through very complex and costly sampling campaigns. Finding efficient proxies to predict the risk of chemical exposure in humans is an urgent need to cover large areas and populations at a reasonable cost. We conducted an exploratory study to characterize the human chemical exposome in maternal blood and placenta samples of a population-based birth cohort in Barcelona (2018-2021). Ultimate HRMS-based approaches were applied including wide-scope target, suspect, and nontarget screening. Forty-two chemicals were identified including pesticides, personal care products, or industrial compounds, among others, in the range of ng/mL and ng/g. In parallel, sewage sludge from the wastewater treatment plants serving the residence areas of the studied population were also screened, showing correlations with the type and concentrations of chemicals found in humans. Our findings were suggestive for the potential use of sewage sludge as a proxy of the human exposure and its application in early warning systems to prevent bioaccumulation of hazardous chemicals.

A Simple and Rapid Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry Method for the Quantitation of Pharmaceuticals and Related Compounds in Mussels and Oysters

A simple, rapid ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been developed and optimized for the quantitation of a range of pharmaceuticals, metabolites, and related bioactive compounds in the bivalve mollusc species mussels (Mytilus edulis) and Pacific oysters (Crassostrea gigas). Shellfish tissues were extracted using a simple solvent-based extraction method prior to concentration and purification by pass-through solid-phase extraction and quantified using stable isotope dilution MS/MS. The analytes covered a range of therapeutic classes including antidepressants, anticonvulsants, beta-blockers, and antiplatelets. Of the 34 compounds included in the present study initially, 28 compounds were found to demonstrate acceptable performance. Performance was assessed by examining extraction efficiencies, matrix effects, sensitivity, and within- and between-batch precision. The results show that as indicated by acceptable HorRat and accuracy values, the method is fit for purpose. Application of this method to environmental mussel and oyster samples revealed the presence of 12 compounds at quantifiable concentrations, with the antidepressant sertraline being present at the highest level, reaching a concentration of 6.12 ng/g in mussel tissue. © 2021 Crown copyright. Environmental Toxicology and Chemistry 2021;40:3263-3274. © 2021 SETAC. This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

SARS-CoV-2 RNA detected in urban wastewater from Porto, Portugal: Method optimization and continuous 25-week monitoring

Research on the emerging COVID-19 pandemic is demonstrating that wastewater infrastructures can be used as public health observatories of virus circulation in human communities. Important efforts are being organized worldwide to implement sewage-based surveillance of SARS-CoV-2 that can be used for preventive or early warning purposes, informing preparedness and response measures. However, its successful implementation requires important and iterative methodological improvements, as well as the establishment of standardized methods. The aim of this study was to develop a continuous monitoring protocol for SARS-CoV-2 in wastewater, that could be used to model virus circulation within the communities, complementing the current clinical surveillance. Specific objectives included (1) optimization and validation of a method for virus quantification; (2) monitoring the time-evolution of SARS-CoV-2 in wastewater from two wastewater treatment plants (WWTPs) in the city of Porto, Portugal. Untreated wastewater samples were collected weekly from the two WWTPs between May 2020 and March 2021, encompassing two COVID-19 incidence peaks in the region (mid-November 2020 and mid-January 2021). In the first stage of this study, we compared, optimized and selected a sampling and analysis protocol that included virus concentration through centrifugation, RNA extraction from both liquid and solid fractions and quantification by reverse transcription quantitative PCR (RT-qPCR). In the second stage, we used the selected methodology to track SARS-CoV-2 in the collected wastewater over time. SARS-CoV-2 RNA was detected in 39 and 37 out of 48 liquid and solid fraction samples of untreated wastewater, respectively. The copy numbers varied throughout the study between 0 and 0.15 copies/ng RNA and a good fit was observed between the SARS-CoV-2 RNA concentration in the untreated wastewater and the COVID-19 temporal trends in the study region. We also analyzed eight samples from the treated effluent and found no SARS-CoV-2 RNA detection after tertiary treatment and UV disinfection. In agreement with the recent literature, the results from this study support the use of wastewater-based surveillance to complement clinical testing and evaluate temporal and spatial trends of the current pandemic.

Examination of single-stage anaerobic and anoxic/aerobic and dual-stage anaerobic-anoxic/aerobic digestion to remove pharmaceuticals from municipal biosolids

Many trace contaminants of emerging concern (CECs) including a number of pharmaceutically active compounds are not effectively removed during conventional wastewater treatment processes and instead accumulate in wastewater sludge. Unfortunately, many existing sludge stabilization treatments such as anaerobic digestion (AD) also have limited effectiveness against many of these CECs including the four pharmaceuticals ibuprofen, diclofenac, carbamazepine, and azithromycin which can then enter the environment through the disposal or land application of biosolids. Single-stage AD, single-stage cycling aerobic-anoxic (AERO/ANOX) and sequential digesters (AD followed by an AERO/ANOX digester) at sludge retention times (SRT) of 5 to 20-days were evaluated side-by-side to assess their effectiveness in removing pharmaceuticals and conventional organic matter. Single-stage ADs (35 °C) and AERO/ANOX (22 °C) digesters effectively removed total solids while sequential AD + AERO/ANOX digesters offered further improvements. Ibuprofen was not effectively removed during AD and resulted in up to a 23 ± 8% accumulation. However, ibuprofen was completely removed during AERO/ANOX digestion and in several sequential digestion scenarios. Each type of digestion was less effective against carbamazepine with slight (3 ± 2%) accumulations to low levels (14 ± 1%) of removals in each type of digestion studied. Diclofenac was more effectively removed with up 30 ± 3% to 39 ± 4% reductions in the single-stage digesters (AD and AERO/ANOX, respectively). While sequential digestion scenarios with the longest aerobic SRTs significantly increased diclofenac removals from their first-stage digesters, scenarios with the longest anaerobic SRTs actually decreased removals from first-stage digesters, possibly due to reversible biotransformation of diclofenac conjugates/metabolites. Up to 43 ± 6% of azithromycin was removed in AERO/ANOX digesters, while the best performing sequential-digester scenario removed up to 63 ± 7% of azithromycin. This study shows that different digester configurations can reduce the CEC burden in biosolids while also greatly reducing their volumes for disposal, although none can remove CECs completely.

Carbamazepine Levels Related to the Demographic Indicators in Groundwater of Densely Populated Area

Consumption of pharmaceuticals by people is growing. Carbamazepine (CBZ) is an extensively used anti-epileptic drug that is recalcitrant to degradation. As a result, CBZ has been widely detected in the aquatic ecosystem due to its daily consumption and drainage in sewage systems. Leakages from sewage networks and septic tanks may represent one of the main sources of CBZ in groundwater. In this study, CBZ concentrations in groundwater and their correlations with the demographic structure of the population were investigated in the densely populated Milan urban area. Seventy-six demographic variables were retrieved from the Italian Population and Housing census. Twenty-one groundwater samples were collected from unconfined and semi-confined aquifers of the Milan area and the concentration of CBZ was measured. Groundwater CBZ levels in both aquifers were associated with the demographic data within a circular buffer with a radius of 1.5 km. All data were analyzed using a multivariate statistical approach. The results showed a significant association (p < 0.05) between CBZ concentrations and specific demographic segments of the population. Higher CBZ concentrations were found to be associated with the population aged 70 years and over (aging index), and with families having children aged under 5 years (family index). In addition, the divorce index was correlated with the high concentration of CBZ, whereas the educated and sexagenarian population showed a negative correlation. Our results indicated that the contamination of CBZ follows the same pattern in unconfined and semi-confined aquifers, which are used for drinking water purposes in Milan area. Therefore, changing the CBZ consumption pattern or replacing CBZ with other drugs may strongly influence groundwater contamination of the investigated area.

Challenges and Current Status of the Biological Treatment of PFAS-Contaminated Soils

Per- and polyfluoroalkyl substances (PFAS) are Synthetic Organic Compounds (SOCs) which are of current concern as they are linked to a myriad of adverse health effects in mammals. They can be found in drinking water, rivers, groundwater, wastewater, household dust, and soils. In this review, the current challenge and status of bioremediation of PFAs in soils was examined. While several technologies to remove PFAS from soil have been developed, including adsorption, filtration, thermal treatment, chemical oxidation/reduction and soil washing, these methods are expensive, impractical for in situ treatment, use high pressures and temperatures, with most resulting in toxic waste. Biodegradation has the potential to form the basis of a cost-effective, large scale in situ remediation strategy for PFAS removal from soils. Both fungal and bacterial strains have been isolated that are capable of degrading PFAS; however, to date, information regarding the mechanisms of degradation of PFAS is limited. Through the application of new technologies in microbial ecology, such as stable isotope probing, metagenomics, transcriptomics, and metabolomics there is the potential to examine and identify the biodegradation of PFAS, a process which will underpin the development of any robust PFAS bioremediation technology.

Performance of butyl rubber-based macroporous sorbents as passive samplers

In this study, two macroporous butyl rubber (BR)-based sorbents prepared in benzene (H-BR) and in cyclohexane (L-BR) with different porosities were synthesized by cryogelation technique. Their performances as a passive sampler were studied and then compared with commercially available silicon rubber (polydimethylsiloxane, PDMS) passive sampler. For that aim, polycyclic aromatic hydrocarbon (PAH) absorption rates of the sorbents in the short-term and their accumulation capacities in the long-term periods were investigated. Four PAHs (naphthalene, phenanthrene, fluoranthene, and pyrene) with a different number of aromatic rings were utilized. The concentrations of the PAHs in solutions were quantified by fluorescence spectrophotometer. The results showed that the BR sampler prepared in benzene (H-BR) generally has the highest absorption rates for all PAHs. The rate constants k (h^-1) of the H-BR, L-BR, and PDMS samplers were found as 1.07, 0.55, and 0.55 for naphthalene; 0.73, 0.16, and 0.09 for phenanthrene; 0.24, 0.26, and 0.08 for fluoranthene; and 0.97, 0.38, and 0.17 for pyrene, respectively. The highest PAH absorption capacity was found for the BR sorbents prepared in benzene for all PAHs. Thus, benzene was selected as the organic solvent rather than cyclohexane for further studies in the preparation of butyl rubber-based samplers. The H-BR possessing the highest absorption rate and capacity underlines their usage as a capable passive sampler for both short- and long-term monitoring activities in the aquatic environments.

A Review on the Fate of Legacy and Alternative Antimicrobials and Their Metabolites during Wastewater and Sludge Treatment

Antimicrobial compounds are used in a broad range of personal care, consumer and healthcare products and are frequently encountered in modern life. The use of these compounds is being reexamined as their safety, effectiveness and necessity are increasingly being questioned by regulators and consumers alike. Wastewater often contains significant amounts of these chemicals, much of which ends up being released into the environment as existing wastewater and sludge treatment processes are simply not designed to treat many of these contaminants. Furthermore, many biotic and abiotic processes during wastewater treatment can generate significant quantities of potentially toxic and persistent antimicrobial metabolites and byproducts, many of which may be even more concerning than their parent antimicrobials. This review article explores the occurrence and fate of two of the most common legacy antimicrobials, triclosan and triclocarban, their metabolites/byproducts during wastewater and sludge treatment and their potential impacts on the environment. This article also explores the fate and transformation of emerging alternative antimicrobials and addresses some of the growing concerns regarding these compounds. This is becoming increasingly important as consumers and regulators alike shift away from legacy antimicrobials to alternative chemicals which may have similar environmental and human health concerns.

From bench to bedside: Biosensing strategies to evaluate endocrine disrupting compounds based on epigenetic events and their potential use in medicine

The relationship between endocrine system disorders and health risks due to chemical environmental compounds has become a growing concern in recent years. Involuntary exposure to endocrine disruptors (EDCs) is associated with the worldwide increase of diseases such as cancer, obesity, diabetes, and neurocortical disorders. EDCs are compounds that target the nuclear hormonereceptors (NHR) leading to epigenetic changes. Consequently, the use of biosensing strategies based on epigenetic events have a great potential to provide outstanding information about the exposition of EDCs and their evaluation in human health. This review addresses the novel trends in biosensing EDCs evaluation based on DNA methylation assays associated with different human diseases.

Computational analysis of SARS-CoV-2/COVID-19 surveillance by wastewater-based epidemiology locally and globally: Feasibility, economy, opportunities and challenges

With the economic and practical limits of medical screening for SARS-CoV-2/COVID-19 coming sharply into focus worldwide, scientists are turning now to wastewater-based epidemiology (WBE) as a potential tool for assessing and managing the pandemic. We employed computational analysis and modeling to examine the feasibility, economy, opportunities and challenges of enumerating active coronavirus infections locally and globally using WBE. Depending on local conditions, detection in community wastewater of one symptomatic/asymptomatic infected case per 100 to 2,000,000 non-infected people is theoretically feasible, with some practical successes now being reported from around the world. Computer simulations for past, present and emerging epidemic hotspots (e.g., Wuhan, Milan, Madrid, New York City, Teheran, Seattle, Detroit and New Orleans) identified temperature, average in-sewer travel time and per-capita water use as key variables. WBE surveillance of populations is shown to be orders of magnitude cheaper and faster than clinical screening, yet cannot fully replace it. Cost savings worldwide for one-time national surveillance campaigns are estimated to be in the million to billion US dollar range (US$), depending on a nation's population size and number of testing rounds conducted. For resource poor regions and nations, WBE may represent the only viable means of effective surveillance. Important limitations of WBE rest with its inability to identify individuals and to pinpoint their specific locations. Not compensating for temperature effects renders WBE data vulnerable to severe under-/over-estimation of infected cases. Effective surveillance may be envisioned as a two-step process in which WBE serves to identify and enumerate infected cases, where after clinical testing then serves to identify infected individuals in WBE-revealed hotspots. Data provided here demonstrate this approach to save money, be broadly applicable worldwide, and potentially aid in precision management of the pandemic, thereby helping to accelerate the global economic recovery that billions of people rely upon for their livelihoods.

Computational analysis of SARS-CoV-2/COVID-19 surveillance by wastewater-based epidemiology locally and globally: Feasibility, economy, opportunities and challenges

With the economic and practical limits of medical screening for SARS-CoV-2/COVID-19 coming sharply into focus worldwide, scientists are turning now to wastewater-based epidemiology (WBE) as a potential tool for assessing and managing the pandemic. We employed computational analysis and modeling to examine the feasibility, economy, opportunities and challenges of enumerating active coronavirus infections locally and globally using WBE. Depending on local conditions, detection in community wastewater of one symptomatic/asymptomatic infected case per 100 to 2,000,000 non-infected people is theoretically feasible, with some practical successes now being reported from around the world. Computer simulations for past, present and emerging epidemic hotspots (e.g., Wuhan, Milan, Madrid, New York City, Teheran, Seattle, Detroit and New Orleans) identified temperature, average in-sewer travel time and per-capita water use as key variables. WBE surveillance of populations is shown to be orders of magnitude cheaper and faster than clinical screening, yet cannot fully replace it. Cost savings worldwide for one-time national surveillance campaigns are estimated to be in the million to billion US dollar range (US$), depending on a nation's population size and number of testing rounds conducted. For resource poor regions and nations, WBE may represent the only viable means of effective surveillance. Important limitations of WBE rest with its inability to identify individuals and to pinpoint their specific locations. Not compensating for temperature effects renders WBE data vulnerable to severe under-/over-estimation of infected cases. Effective surveillance may be envisioned as a two-step process in which WBE serves to identify and enumerate infected cases, where after clinical testing then serves to identify infected individuals in WBE-revealed hotspots. Data provided here demonstrate this approach to save money, be broadly applicable worldwide, and potentially aid in precision management of the pandemic, thereby helping to accelerate the global economic recovery that billions of people rely upon for their livelihoods.

Toxicity Reduction of Industrial and Municipal Wastewater by Advanced Oxidation Processes (Photo-Fenton, UVC/H2O2, Electro-Fenton and Galvanic Fenton): A Review

The application of Fenton-based advanced oxidation processes (AOPs), such as photo-Fenton or electro-Fenton for wastewater treatment have been extensively studied in recent decades due to its high efficiency for the decomposition of persistent organic pollutants. Usually Fenton-based AOPs are used for the degradation of targeted pollutant or group of pollutants, which often leads to the formation of toxic by-products possessing a potential environmental risk. In this work, we have collected and reviewed recent findings regarding the feasibility of Fenton-based AOPs (photo-Fenton, UVC/H2O2, electro-Fenton and galvanic Fenton) for the detoxification of real municipal and industrial wastewaters. More specifically, operational conditions, relevance and suitability of different bioassays for the toxicity assessment of various wastewater types, cost estimation, all of which compose current challenges for the application of these AOPs for real wastewater detoxification are discussed.

Occurrence of the Persistent Antimicrobial Triclosan in Microwave Pretreated and Anaerobically Digested Municipal Sludges under Various Process Conditions

Treatment of emerging contaminants, such as antimicrobials, has become a priority topic for environmental protection. As a persistent, toxic, and bioaccumulative antimicrobial, the accumulation of triclosan (TCS) in wastewater sludge is creating a potential risk to human and ecosystem health via the agricultural use of biosolids. The impact of microwave (MW) pretreatment on TCS levels in municipal sludge is unknown. This study, for the first time, evaluated how MW pretreatment (80 and 160 °C) itself and together with anaerobic digestion (AD) under various sludge retention times (SRTs: 20, 12, and 6 days) and temperatures (35 and 55 °C) can affect the levels of TCS in municipal sludge. TCS and its potential transformation products were analyzed with ultra-high-performance liquid chromatography and tandem mass spectrometry. Significantly higher TCS concentrations were detected in sludge sampled from the plant in colder compared to those in warmer temperatures. MW temperature did not have a discernible impact on TCS reduction from undigested sludge. However, AD studies indicated that compared to controls (no pretreatment), MW irradiation could make TCS more amenable to biodegradation (up to 46%), especially at the elevated pretreatment and digester temperatures. At different SRTs studied, TCS levels in the thermophilic digesters were considerably lower than that of in the mesophilic digesters.

Smarter Sediment Screening: Effect-Based Quality Assessment, Chemical Profiling, and Risk Identification

Sediments play an essential role in the functioning of aquatic ecosystems but simultaneously retain harmful compounds. However, sediment quality assessment methods that consider the risks caused by the combined action of all sediment-associated contaminants to benthic biota are still underrepresented in water quality assessment strategies. Significant advancements have been made in the application of effect-based methods, but methodological improvements can still advance sediment risk assessment. The present study aimed to explore such improvements by integrating effect-monitoring and chemical profiling of sediment contamination. To this end, 28 day life cycle bioassays with Chironomus riparius using intact whole sediment cores from contaminated sites were performed in tandem with explorative chemical profiling of bioavailable concentrations of groups of legacy and emerging sediment contaminants to investigate ecotoxicological risks to benthic biota. All contaminated sediments caused effects on the resilient midge C. riparius, stressing that sediment contamination is ubiquitous and potentially harmful to aquatic ecosystems. However, bioassay responses were not in line with any of the calculated toxicity indices, suggesting that toxicity was caused by unmeasured compounds. Hence, this study underlines the relevance of effect-based sediment quality assessment and provides smarter ways to do so.

Solar light active silver/iron oxide/zinc oxide heterostructure for photodegradation of ciprofloxacin, transformation products and antibacterial activity

This paper reports on the multitasking potential of a silver/iron oxide/zinc oxide (Ag/Fe₂O₃/ZnO) heterostructure, which was used for the photocatalytic decomposition of ciprofloxacin (CPX) and bacterial disinfection. The Ag/Fe₂O₃/ZnO heterostructure was successfully prepared using a facile precipitation method, and characterization results showed interesting structural, morphological, compositional and luminescent properties. The morphological results of the prepared heterostructure confirmed the deposition of Ag nanoparticles onto the surface of ZnO nanoplates and Fe₂O₃ nanorods. Treatment studies showed that the Ag/Fe₂O₃/ZnO heterostructure had superior solar light driven photocatalytic activity towards CPX degradation (76.4%) compared to bare Fe₂O₃ nanorods (43.2%) and ZnO nanoplates (63.1%), Ag/Fe₂O₃ (28.2%) and Ag/ZnO (64.5%) under optimized conditions (initial CPX concentration: 10 mg/L; pH 4; catalyst loading: 0.3 g/L). Reactive species study confirmed the roles of e^-, h⁺, OH and O₂^- in the photocatalytic degradation process. This photocatalytic behaviour of the Ag/Fe₂O₃/ZnO heterostructure could be attributed to the improved full solar spectrum harvesting capacity, separation of charge carriers and migration of e^-/h⁺ across the heterostructure interface. In addition, the Ag/Fe₂O₃/ZnO heterostructure also showed good antibacterial activity against Escherichia coli (E. coli) under both dark and visible light conditions. This might be due to generation of reactive oxygen species during the reaction. To the best of our knowledge, this is the first study till date on the utilization of Ag/Fe₂O₃/ZnO heterostructure for the photocatalytic degradation of CPX and E. coli bacteria disinfection. Therefore, this work offers an attractive path to design ZnO-based ternary heterostructures for solar-driven applications in wastewater remediation.

Alcohol and nicotine consumption trends in three U.S. communities determined by wastewater-based epidemiology

Wastewater-based epidemiology (WBE), an emerging tool for monitoring public health in near real-time, is used extensively in Europe but applications to U.S. populations are still scarce. In this longitudinal study, raw wastewater was collected monthly from three U.S. cities as 24-h weekday composites and analyzed for evidence of alcohol and tobacco consumption. Over the 11-month sampling period, biomarkers of stimulant use were detected in wastewater by isotope dilution liquid chromatography tandem mass spectrometry in units of μg/L (ethyl sulfate, 1.6-25.1; nicotine, 0.6-26.7; cotinine, 0.2-3.8; and 3‑hydroxycotinine, 0.3-3.8). Average consumption rates in the three communities were calculated using detected biomarker levels in conjunction with wastewater flow rates, metabolic excretion factors, and population size data. Computed average per-capita consumption rates estimated for the sub-population aged 15 and above for alcohol (13.4 ± 5.6 L/y/person) and daily consumption of nicotine by smokers (14.2 ± 3.6 cigarettes/d/person) were in good agreement with U.S. survey data (9.0 L/y/person; 14.2 cigarettes/d/smoker). The WBE approach also captured impacts of temporal population influx on substance consumption patterns. This first U.S. WBE study to track recreational use of stimulants longitudinally and concurrently in multiple American cities highlights opportunities for collecting robust public health information from wastewater anonymously, economically and in near real-time.

Distribution and fate of synthetic phenolic antioxidants in various wastewater treatment processes in Canada

Synthetic phenolic antioxidants (SPAs) are of emerging concern due to their potential environmental risks. However, the environmental occurrence and fate of SPAs are poorly understood. In this study, 13 SPAs were analyzed in 70 liquid and 21 solid samples from 12 wastewater treatment plants (WWTPs) in 2016 to investigate the distribution and composition of SPAs in different wastewater treatment processes in Canada. Wastewater samples were liquid-liquid extracted and biosolids were treated using ultrasonic assisted solvent extraction. SPAs were analyzed by ultra-performance liquid chromatography-tandem mass spectrometry. The concentrations of total SPAs were in the ranges of 71-3193 ng L^-1 in influent, less than method quantification limits (MQLs)-520 ng L^-1 in effluent, and 479-4794 ng g^-1 in biosolids (dry weight (dw)). SPAs were effectively removed (median >75%) from the liquid stream in most WWTPs. In one aerated lagoon and two primary treatment sites, low removal efficiency (median -26%-43%) was observed for 4-tert-octylphenol (4-tOP). These results indicate that wastewater effluent is a vector for SPAs, including the endocrine disruptor 4-tOP, to aquatic environments. The mass balance approximation found major removal mechanisms are sludge sorption/separation and degradation. A preliminary risk assessment suggested that most SPAs in WWTP effluent were unlikely to pose ecotoxicological risks to aquatic organisms in the receiving waters. Future research should evaluate the environmental risks of SPAs associated with land application of biosolids and investigate the occurrence and fate of the degradation products of these contaminants.

Obesity: A New Adverse Effect of Antibiotics?

Since the introduction of antibiotics, they have been used freely, with their prescription occurring almost always when they were not necessary. The other major form of contact between humans and antibiotics, now unintentionally, is with the large amount of these drugs in the environment and in our food. The relationship between antibiotic use and the development of obesity has become increasingly evident and apparent in humans, with some authors clearly establishing the relationship between the large-scale use of antibiotics in the past 70 years and the “epidemic” of obesity that has occurred in parallel, almost as an adverse epidemiological effect. In the research effort entertained herein, a correlation between the use and abuse of antibiotics and the onset of obesity was investigated.

Municipal Wastewater as a Microbial Surveillance Platform for Enteric Diseases: A Case Study for Salmonella and Salmonellosis

Municipal wastewater (MW) contains a conglomeration of human enteric microbiota from a community and, hence, represents a potential surveillance tool for gastrointestinal infectious disease burden at the community level. To evaluate this, the concentration of Salmonella in MW samples from Honolulu, Hawaii, was monitored over a 54-week period, which showed positive and significant linear and rank correlation with clinical salmonellosis case numbers over the same period. Salmonella isolates were obtained from the MW samples and then compared with clinical isolates obtained by the Hawaii Department of Health State Laboratories over the same period. The MW isolate collection contained 34 serotypes, and the clinical isolate collection contained 47 serotypes, 21 of which were shared between the two isolate collections, including nine of the 12 most commonly detected clinical serotypes. Most notably, nine Salmonella strains, including one outbreak-associated Paratyphi B strain and eight other clinically rare strains, were shared and concurrently detected between the MW and the clinical isolate collections, indicating the feasibility of using enteric pathogens in the MW as a timely indication of community enteric disease activity.

Wastewater-based epidemiology to assess pan-European pesticide exposure

Human biomonitoring, i.e. the determination of chemicals and/or their metabolites in human specimens, is the most common and potent tool for assessing human exposure to pesticides, but it suffers from limitations such as high costs and biases in sampling. Wastewater-based epidemiology (WBE) is an innovative approach based on the chemical analysis of specific human metabolic excretion products (biomarkers) in wastewater, and provides objective and real-time information on xenobiotics directly or indirectly ingested by a population. This study applied the WBE approach for the first time to evaluate human exposure to pesticides in eight cities across Europe. 24 h-composite wastewater samples were collected from the main wastewater treatment plants and analyzed for urinary metabolites of three classes of pesticides, namely triazines, organophosphates and pyrethroids, by liquid chromatography-tandem mass spectrometry. The mass loads (mg/day/1000 inhabitants) were highest for organophosphates and lowest for triazines. Different patterns were observed among the cities and for the various classes of pesticides. Population weighted loads of specific biomarkers indicated higher exposure in Castellon, Milan, Copenhagen and Bristol for pyrethroids, and in Castellon, Bristol and Zurich for organophosphates. The lowest mass loads (mg/day/1000 inhabitants) were found in Utrecht and Oslo. These results were in agreement with several national statistics related to pesticides exposure such as pesticides sales. The daily intake of pyrethroids was estimated in each city and it was found to exceed the acceptable daily intake (ADI) only in one city (Castellon, Spain). This was the first large-scale application of WBE to monitor population exposure to pesticides. The results indicated that WBE can give new information about the "average exposure" of the population to pesticides, and is a useful complementary biomonitoring tool to study population-wide exposure to pesticides.

Occurrence, temporal variation, and estrogenic burden of five parabens in sewage sludge collected across the United States

Five parabens used as preservatives in pharmaceuticals and personal care products (PPCPs) were measured in sewage sludges collected at 14 U.S. wastewater treatment plants (WWTPs) located in nine states. Detected concentration ranges (ng/g, dry weight) and frequencies were as follows: methyl paraben (15.9 to 203.0; 100%), propyl paraben (0.5 to 7.7; 100%), ethyl paraben (<0.6 to 2.6; 63%), butyl paraben (<0.4 to 4.3; 42%) and benzyl paraben (<0.4 to 3.3; 26%). The estrogenicity inherent to the sum of parabens detected in sewage sludge (ranging from 10.1 to 500.1pg/kg 17β-estradiol equivalents) was insignificant when compared to the 10⁶-times higher value calculated for natural estrogens reported in the literature to occur in sewage sludge. Temporal monitoring at one WWTP provided insights into temporal and seasonal variations in paraben concentrations. This is the first report on the occurrence of five parabens in sewage sludges from across the U.S., and internationally, the first on temporal variations of paraben levels in sewage sludge. Study results will help to inform the risk assessment of sewage sludge destined for land application (biosolids).

Low-molecular-weight organic acids correlate with cultivar variation in ciprofloxacin accumulation in Brassica parachinensis L

To understand the mechanism controlling cultivar differences in the accumulation of ciprofloxacin (CIP) in Chinese flowering cabbage (Brassica parachinensis L.), low-molecular-weight organic acids (LMWOAs) secreted from the roots of high- and low-CIP cultivars (Sijiu and Cutai, respectively) and their effects on the bioavailability of CIP in soil were investigated. Significant differences in the content of LMWOAs (especially maleic acid) between the two cultivars played a key role in the variation in CIP accumulation. Based on the Freundlich sorption coefficient (K_f) and distribution coefficient (K_d), the presence of LMWOAs reduced the CIP sorption onto soil particles, and higher concentrations of LMWOAs led to less CIP sorption onto soil. On the other hand, LMWOAs enhanced CIP desorption by lowering the solution pH, which changed the surface charge of soil particles and the degree of CIP ionization. LMWOAs promoted CIP desorption from soil by breaking cation bridges and dissolving metal cations, particularly Cu²⁺. These results implied that the LMWOAs (mainly maleic acid) secreted from Sijiu inhibited CIP sorption onto soil and improved CIP desorption from soil to a greater extent than those secreted from Cutai, resulting in higher bioavailability of CIP and more uptake and accumulation of CIP in the former.

Environmental epigenomics: Current approaches to assess epigenetic effects of endocrine disrupting compounds (EDC's) on human health

Environmental Epigenomics is a developing field to study the epigenetic effect on human health from exposure to environmental factors. Endocrine disrupting chemicals have been detected primarily in pharmaceutical drugs, personal care products, food additives, and food containers. Exposure to endocrine-disrupting chemicals (EDCs) has been associated with a high incidence and prevalence of many endocrine-related disorders in humans. Nevertheless, further evidence is needed to establish a correlation between exposure to EDC and human disorders. Conventional detection of EDCs is based on chemical structure and concentration sample analysis. However, substantial evidence has emerged, suggesting that cell exposure to EDCs leads to epigenetic changes, independently of its chemical structure with non-monotonic low-dose responses. Consequently, a paradigm shift in toxicology assessment of EDCs is proposed based on a comprehensive review of analytical techniques used to evaluate the epigenetic effects. Fundamental insights reported elsewhere are compared in order to establish DNA methylation analysis as a viable method for assessing endocrine disruptors beyond the conventional study approach of chemical structure and concentration analysis.

3D printed self-driven thumb-sized motors for in-situ underwater pollutant remediation

Green fuel-driven thumb sized motors (TSM) were designed and optimized by 3D printing to explore their in-situ remediation applications in rare studied underwater area. Combined with areogel processing and specialized bacteria domestication, each tiny TSM could realize large area pollutant treatment precisely in an impressive half-automatically manner.

Occurrence and fate of PBDEs and novel brominated flame retardants in a wastewater treatment plant in Harbin, China

Wastewater treatment plant (WWTP) is considered to be an important medium for the transport and transformation of organic pollutants. This study attempted to comprehensively investigate polybrominated diphenyl ethers (PBDEs) and novel brominated flame retardants (NBFRs) in a WWTP in Harbin, one of the main "Old Industrial Base" in China. The mean concentrations of the total PBDEs in the influent, effluent, and sludge were 152 ng/L, 16.2 ng/L, and 503 g/g dw, respectively, which were at the low end of the global range. BDE-209 was the most abundant congener, with contributions to the total PBDE ranging from 90.5 to 98.5 %. The level of the total NBFRs ranged from 24.5 to 107 ng/L, 0.95 to 20.3 ng/L, and 305 to 1202 ng/g dw in the influent, effluent, and sludge, respectively. For NBFRs, DBDPE was the most abundant congener (38.8-50.5 %), followed by BEHTBP (11.0-35.0 %). The ratio for DBDPE/BDE-209 (0.62 ± 0.42) was found less than 1 in sludge, which indicated that Deca-BDE is still the major BFR product in this city. Source identification suggested that indoor dust should be an important source of BFRs in the WWTP. Approximately 20.8 and 7.79 kg of PBDEs and NBFRs on annual basis were removed with the sludge. Biodegradation could play an important role on the fate of BFRs in the WWTP, which is required for future research.

Organic Contaminants in Chinese Sewage Sludge: A Meta-Analysis of the Literature of the Past 30 Years

The production of sewage sludge is increasing in China but with unsafe disposal practices, causing potential risk to human health and the environment. Using literature from the past 30 years (N = 159), we conducted a meta-analysis of organic contaminants (OCs) in Chinese sludge. Most data were available from developed and populated regions, and no data were found for Tibet. Since 1987, 35 classes of chemicals consisting of 749 individual compounds and 1 mixture have been analyzed, in which antibiotics and polycyclic aromatic hydrocarbons (PAHs) were the most targeted analytes. For 13 classes of principal OCs (defined as chemicals detected in over five studies) in sludge, the median (expressed in nanograms per gram dry weight) was the highest for phthalate esters (27 900), followed by alkylphenol polyethoxylates (12 000), synthetic musks (5800), antibiotics (4240), PAHs (3490), ultraviolet stabilizers (670), bisphenol analogs (160), organochlorine pesticides (110), polybrominated diphenyl ethers (100), pharmaceuticals (84), hormones (69), perfluorinated compounds (21), and polychlorinated biphenyls (15). Concentrations of PAHs in sludges collected between 1998 and 2012 showed a decreasing trend. Study findings suggest the need for a Chinese national sewage sludge survey to identify and regulate toxic OCs, ideally employing both targeted as well as nontargeted screening approaches.

Modeling the pH-mediated extraction of ionizable organic contaminants to improve the quality of municipal sewage sludge destined for land application

A model was developed to assess the impact of adding acids and bases to processed municipal sewage sludge (MSS) to mobilize contaminants, facilitating their removal from sludge by flushing prior to land application. Among 312 organic contaminants documented to occur in U.S. MSS, 71 or 23% were identified as ionizable organic contaminants (IOCs), contributing a disproportionately large fraction of 82% of the total mass of sludge-borne contaminants. Detected IOCs included 57 pharmaceuticals and personal care products, 12 perfluorinated compounds, one surfactant and one pesticide. Annually, about 2000t of IOCs were estimated to be released to U.S. soils via land-application of MSS. A partitioning model developed to assess the impact of pH on hydrophobic sorption revealed that between 36 and 85% of the mass of individual classes of IOCs potentially could be desorbed from MSS via pH adjustment and flushing. Thus, modeling results suggest that a sequential pH treatment [acidic (~pH2) followed by basic (~pH12) treatment] has the potential to reduce the burden of harmful IOCs in MSS applied on U.S. land by up to 40±16t annually. This approach may serve as a cost-effective treatment process that can be implemented easily in existing sludge treatment infrastructure in the U.S. and worldwide, serving to significantly improve the quality of MSS destined for land application.

Application of self-sustaining smouldering combustion for the destruction of wastewater biosolids

Managing biosolids, the major by-product from wastewater treatment plants (WWTPs), persists as a widespread challenge that often constitutes the majority of WWTP operating costs. Self-sustained smouldering combustion is a new approach for organic waste treatment, in which the waste - the combustion fuel - is destroyed in an energy efficient manner after mixing it with sand. Smouldering has never been applied to biosolids. Column experiments, using biosolids obtained from a WWTP, were employed to identify if, and under what conditions, smouldering could be used for treating biosolids. The parameter space in which smouldering was self-sustaining was mapped as a function of key system metrics: (1) sand/biosolids mass fraction, (2) biosolids moisture content, and (3) forced air flux. It was found that a self-sustaining reaction is achievable using biosolids with water content as high as 80% (with a biosolids lower heating value greater than 1.6 kJ/g). Moreover, results suggest that operator-controlled air flux can assist in keeping the reaction self-sustaining in response to fluctuations in biosolids properties. This proof-of-concept demonstrates the potential for smouldering as a new energy efficient biosolids disposal method for very wet (i.e., minimally processed) biosolids that may offer WWTPs significant operating cost savings. This study emphasizes smouldering's usefulness as a novel waste management technique.

Occurrence and spatial distribution of 158 pharmaceuticals, drugs of abuse and related metabolites in offshore seawater

The occurrence and spatial distribution of 158 pharmaceuticals and drugs of abuse were studied in seawater of the Eastern Mediterranean Sea (Saronikos Gulf and Elefsis Bay in central Aegean Sea). This area is affected by various anthropogenic pressures as it receives the treated wastewater of the greatest Athens area and off-shore input fluxes. This study constitutes the largest one in terms of number of analytes in this environmental compartment. It provides the first evidence on the occurrence of several pharmaceuticals in marine environment including amoxicillin, lidocaine, citalopram or tramadol, among others. 22 samples were collected at three different depths in 9 sampling stations in order to assess the presence and the spatial distribution of the target compounds. A multi-residue method based on solid phase extraction and liquid chromatography coupled to tandem mass spectrometry was developed for the determination of the 158 target substances and validated for seawater sample analysis. 38 out of the 158 target compounds were detected, 15 of them with frequencies of detection equal to or higher than 50%. The highest detected values corresponded to amoxicillin, caffeine and salicylic acid, with concentrations in the range of < 5.0-127.8 ng L(-1); 5.2-78.2 ng L(-1) and < 0.4-53.3 ng L(-1), respectively. Inputs from the wastewater treatment plant (WWTP) of Athens revealed to be the main source of pollution in the Inner Saronikos Gulf, whereas, other anthropogenic pressures such as contamination from shipping activity, industrial effluents, dredging and/or inputs from land proved to be also relevant. Τhe concentrations of some compounds varied significantly with depth suggesting that currents play an important role in the dilution of the target compounds.

Triclocarban Influences Antibiotic Resistance and Alters Anaerobic Digester Microbial Community Structure

Triclocarban (TCC) is one of the most abundant organic micropollutants detected in biosolids. Lab-scale anaerobic digesters were amended with TCC at concentrations ranging from the background concentration of seed biosolids (30 mg/kg) to toxic concentrations of 850 mg/kg to determine the effect on methane production, relative abundance of antibiotic resistance genes, and microbial community structure. Additionally, the TCC addition rate was varied to determine the impacts of acclimation time. At environmentally relevant TCC concentrations (max detect = 440 mg/kg), digesters maintained function. Digesters receiving 450 mg/kg of TCC maintained function under gradual TCC addition, but volatile fatty acid concentrations increased, pH decreased, and methane production ceased when immediately fed this concentration. The concentrations of the mexB gene (encoding for a multidrug efflux pump) were higher with all concentrations of TCC compared to a control, but higher TCC concentrations did not correlate with increased mexB abundance. The relative abundance of the gene tet(L) was greater in the digesters that no longer produced methane, and no effect on the relative abundance of the class 1 integron integrase encoding gene (intI1) was observed. Illumina sequencing revealed substantial community shifts in digesters that functionally failed from increased levels of TCC. More subtle, yet significant, community shifts were observed in digesters amended with TCC levels that did not inhibit function. This research demonstrates that TCC can select for a multidrug resistance encoding gene in mixed community anaerobic environments, and this selection occurs at concentrations (30 mg/kg) that can be found in full-scale anaerobic digesters (U.S. median concentration = 22 mg/kg, mean = 39 mg/kg).

Occurrence and estrogenic potency of eight bisphenol analogs in sewage sludge from the U.S. EPA targeted national sewage sludge survey

As health concerns over bisphenol A (BPA) in consumer products are mounting, this weak estrogen mimicking compound is gradually being replaced with structural analogs, whose environmental occurrence and estrogen risks are not well understood yet. We used high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to determine the concentrations of eight bisphenol analogs in 76 sewage sludge samples collected by the U.S. Environmental Protection Agency (EPA) in 2006/2007 from 74 wastewater treatment plants (WWTPs) in 35 states. Bisphenols were detected at the following concentration ranges (ng/g dry weight) and detection frequencies: BPA (6.5-4700; 100%); bisphenol S (BPS; <1.79-1480; 84%); bisphenol F (BPF; <1.79-242; 68%); bisphenol AF (BPAF; <1.79-72.2; 46%); bisphenol P (BPP; <1.79-6.42; <5%), bisphenol B (BPB; <1.79-5.60; <5%), and bisphenol Z (BPZ; <1.79--66.7; <5%). Bisphenol AP (BPAP) was not detected in any of the samples (<1.79 ng/g dw). Concentrations of BPA in sewage sludge were an order of magnitude higher than those reported in China but similar to those in Germany. The calculated 17β-estradiol equivalents (E2EQ) of bisphenols present in sludge samples were 7.74 (0.26-90.5) pg/g dw, which were three orders of magnitude lower than the estrogenic activity contributed by natural estrogens present in the sludge. The calculated mass loading of bisphenols through the disposal of sludge and wastewater was <0.02% of the total U.S. production. As the usage of BPA is expected to decline further, environmental emissions of BPS, BPF, and BPAF are likely to increase in the future. This study establishes baseline levels and estrogenic activity of diverse bisphenol analogs in sewage sludge.