Comprehensive study of endocrine disrupting compounds using grab and passive sampling at selected wastewater treatment plants in South East Queensland, Australia

Phthalates contamination in sediments: A review of sources, influencing factors, benthic toxicity, and removal strategies

Sediments provide habitat and food for benthos, and phthalates (PAEs) have been detected in numerous river and marine sediments as a widely used plastic additive. PAEs in sediments is not only toxic to benthos, but also poses a threat to pelagic fish and human health through the food chain, so it is essential to comprehensively assess the contamination of sediments with PAEs. This paper presents a critical evaluation of PAEs in sediments, which is embodied in the analysis of the sources of PAEs in sediments from multiple perspectives. Biological production is indispensable, while artificial synthesis is the most dominant, thus the focus was on analyzing the industrial and commercial sources of synthetic PAEs. In addition, since the content of PAEs in sediments varies, some factors affecting the content of PAEs in sediments are summarized, such as the properties of PAEs, the properties of plastics, and environmental factors (sediments properties and hydrodynamic conditions). As endocrine disruptors, PAEs can produce toxicity to its direct contacts. Therefore, the effects of PAEs on benthos immunity, endocrinology, reproduction, development, and metabolism were comprehensively analyzed. In addition, we found that reciprocal inhibition and activation of the systems lead to genotoxicity and apoptosis. Finally, the paper discusses the feasible measures to control PAEs in wastewater and leachate from the perspective of source control, and summarizes the in-situ treatment measures for PAEs contamination in sediments. This paper provides a comprehensive review of PAEs contamination in sediments, toxic effects and removal strategies, and provides an important reference for reducing the contamination and toxicity of PAEs to benthos.

Prevalence of Endocrine Disrupting Chemicals in the urban wastewater treatment systems of Dehradun, India: Daunting presence of Estrone

We quantified the occurrences and seasonal variations of the target endocrine disrupting chemicals (EDCs) at four (two major municipals, and two academic institutions) WWTPs in Dehradun city, Uttarakhand, India. The results showed estrone in higher concentrations at μgL-1 levels in influent among the WWTPs, compared to triclosan (TCS) at ngL-1 levels. An astounding concentration of 123.95 μgL-1 was recorded for the estrone in the influent, which is to date the highest ever recorded, globally. Statistical data treatment was performed to test the distribution of the data (Shapiro-Wilk, Anderson-Darling, Lilliefors, and Jarque-Bera tests), and the significant difference between the mean of the wastewater sample population (ANOVA: F statistics, p values, Mann-Whitney test, Tukey's and Dunn's post hoc analysis). Statistical data treatment indicated EDCs concentration with a bi-modal distribution. The Shapiro-Wilk, Anderson-Darling, Lilliefors, and Jarque-Bera tests elucidate a non-normal distribution for the EDCs sample data. A statistically significant difference (F = 8.46; p < 0.0001) in the seasonal data for the abundance of the target EDCs at the WWTPs have been observed. Highest and significantly different mean EDCs concentrations were recorded during the monsoon, compared to the spring (p = 0.025) and summer (p = 0.0004) seasons in the influent waters. The mean influent concentrations of TCS and estrone in monsoon were 66.45 ngL-1 and 78.02 μgL-1, respectively. Maximum removals were recorded for TCS, while maximum negative removal of ∼293% was observed for estrone in the WWTPs. Particularly, the high levels of estrone in the wastewater pose a significant threat as estrone presence could be led to feminization, dysregulation of reproduction in organisms, and carcinogenesis processes in the environment. This study critically highlights the limitation of the WWTPs in the treatment, degradation, and assimilation of EDCs leading to their hyperaccumulation at WWTP effluents, thereby posing a substantial threat to nearby aquatic ecosystems, human health, and the ecological balance of the region.

Bioanalytical and chemical characterization of organic micropollutant mixtures in long-term exposed passive samplers from the Joint Danube Survey 4: Setting a baseline for water quality monitoring

Monitoring methodologies reflecting the long-term quality and contamination of surface waters are needed to obtain a representative picture of pollution and identify risk drivers. This study sets a baseline for characterizing chemical pollution in the Danube River using an innovative approach, combining continuous three-months use of passive sampling technology with comprehensive chemical (747 chemicals) and bioanalytical (seven in vitro bioassays) assessment during the Joint Danube Survey (JDS4). This is one of the world's largest investigative surface-water monitoring efforts in the longest river in the European Union, which water after riverbank filtration is broadly used for drinking water production. Two types of passive samplers, silicone rubber (SR) sheets for hydrophobic compounds and AttractSPETM HLB disks for hydrophilic compounds, were deployed at nine sites for approximately 100 days. The Danube River pollution was dominated by industrial compounds in SR samplers and by industrial compounds together with pharmaceuticals and personal care products in HLB samplers. Comparison of the Estimated Environmental Concentrations with Predicted No-Effect Concentrations revealed that at the studied sites, at least one (SR) and 4-7 (HLB) compound(s) exceeded the risk quotient of 1. We also detected AhR-mediated activity, oxidative stress response, peroxisome proliferator-activated receptor gamma-mediated activity, estrogenic, androgenic, and anti-androgenic activities using in vitro bioassays. A significant portion of the AhR-mediated and estrogenic activities could be explained by detected analytes at several sites, while for the other bioassays and other sites, much of the activity remained unexplained. The effect-based trigger values for estrogenic and anti-androgenic activities were exceeded at some sites. The identified drivers of mixture in vitro effects deserve further attention in ecotoxicological and environmental pollution research. This novel approach using long-term passive sampling provides a representative benchmark of pollution and effect potentials of chemical mixtures for future water quality monitoring of the Danube River and other large water bodies.

Groundwater contamination pathways of phthalates and bisphenol A: origin, characteristics, transport, and fate - A review

Phthalic acid esters (PAEs) or phthalates and bisphenol A (BPA) are emerging organic contaminants (EOCs) that may harm biota and human health. Humans can be exposed to these contaminants by drinking water consumption from water sources such as groundwater. Before their presence in aquifer systems, phthalates and BPA can be found in many matrices due to anthropogenic activities, which result in long-term transport to groundwater reservoirs by different mechanisms and reaction processes. The worldwide occurrence of phthalates and BPA concentrations in groundwater have ranged from 0.1 × 10^-3 to 3 203.33 µg L^-1 and from 0.09 × 10^-3 to 228.04 µg L^-1, respectively. Therefore, the aim of this review is to describe the groundwater contamination pathways of phthalates and BPA from the main environmental sources to groundwater. Overall, this article provides an overview that integrates phthalate and BPA environmental cycling, from their origin to human reception via groundwater consumption. Additionally, in this review, the readers can use the information provided as a principal basis for existing policy ratification and for governments to develop legislation that may incorporate these endocrine disrupting compounds (EDCs) as priority contaminants. Indeed, this may trigger the enactment of regulatory guidelines and public policies that help to reduce the exposure of these EDCs in humans by drinking water consumption.

Novel miniaturized passive sampling devices based on liquid phase microextraction equipped with cellulose-grafted membranes for the environmental monitoring of phthalic acid esters in natural waters

Phthalic acid esters (PAEs) are considered endocrine disruptors and potential carcinogens. Consequently, efficient and accurate environmental monitoring of trace levels of these organic pollutants is necessary to protect the population against their hazardous effects. Passive sampling techniques have gained notoriety for environmental monitoring and have been proven highly sensitive to temporal variations. This study developed a miniaturized passive sampling device (MPSD) based on hollow fiber liquid-phase microextraction (HF-LPME). The devices were calibrated in the laboratory using an automated calibration system. The results demonstrated the first-order uptake ranges for Diethyl phthalate (DEP), Diisobutyl phthalate (DiBP), Dibutyl phthalate (DBP), Benzyl butyl phthalate (BBP) and Bis(2-ethylhexyl phthalate) (DEHP) between 30 min and 24 h with sampling rates equivalent to 0.009; 0.021; 0.033; 0.085 and 0.003 mL h^-1 respectively (R² between 0.88 and 0.99). The calibrated devices were deployed in 12 marginal lagoons, stretching approximately 330 km along the main river. The extracts recovered from the devices were analyzed by gas chromatography (GC), resulting in the identification and quantification of DEP (0.697-13.7 ng L^-1), DiBP (0.100-4.43 ng L^-1), DBP (0.014-1.21 ng L^-1), BBP (0.218-5.67 ng L^-1), and DEHP (0.002-2.24 ng L^-1). Despite being frequently identified, DEHP concentrations were well below the maximum established limits, revealing a good water quality in terms of the target PAEs. In contrast, screening the extracts using GCxGC was possible to detect other hazardous pollutants such as pesticides, drugs, and their metabolites. The described device was effective and reliable, providing accurate PAE measurements following short exposure periods. In this sense, its deployment during emergency operations, such as accidental discharges of industrial effluents into natural waters, could continuously and cost-effectively monitor water quality.

Evaluation of occurrence, fate and removal of priority phthalate esters (PAEs) in wastewater and sewage sludge by advanced biological treatment, waste stabilization pond and constructed wetland

Phthalate Esters (PAEs), detected in high concentrations generally in treated wastewater discharged from wastewater treatment plants (WWTPs), are important pollutants that restrict the reuse of wastewater. Investigating the fate of these endocrine-disrupting chemicals in WWTPs is crucial in order to protect both receiving environments and ecosystems. For this purpose, di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DNOP) and benzyl butyl phthalate (BBP) in the group of PAEs were monitored in simultaneously both in wastewater and sludge lines of selected two nature-based WWTPs and one advanced biological WWTP. Although it was frequently stated that phthalates were significantly removed in WWTPs in many studies found in literature, negative removal efficiencies of selected phthalates in investigated WWTPs during the sampling period were observed generally in this study. One of the reasons for this concentration increase could be releasing of phthalates from microplastics in wastewater during the treatment process or the desorption of PAEs from treatment sludge. DNOP was the compound with the highest concentration increase at almost each treatment unit of the three WWTPs. On the other hand, total PAEs load was 1997 g d^-1 in advanced biological WWTP and adsorption onto sludge of PAEs were determined as 90%. The side-stream total load returned from the decanter supernatant was 0.02% of the total PAEs load coming to advanced biological WWTP from the sewer system. As a result of detailed statistical analysis, the correlation between raw wastewater and primary clarifier (PC) effluent was determined as an increasing linear relation for DEHP and DNOP. On the other hand, moderate and strong correlations were observed both between septic tank and constructed wetland (CW) processes with raw wastewater. In the waste stabilization pond (WSP), while a significant correlation was not found between the sludge line data, homogeneous variance, strong and moderate correlations were obtained in the wastewater line data. However, while mean differences for all investigated PAEs were not significant (p > 0.05) in the wastewater line, mean differences of DEHP (p < 0.05) were significant in the sludge line according to ANOVA analysis.

Sea Anemones Responding to Sex Hormones, Oxybenzone, and Benzyl Butyl Phthalate: Transcriptional Profiling and in Silico Modelling Provide Clues to Decipher Endocrine Disruption in Cnidarians

Endocrine disruption is suspected in cnidarians, but questions remain how occurs. Steroid sex hormones are detected in corals and sea anemones even though these animals do not have estrogen receptors and their repertoire of steroidogenic enzymes appears to be incomplete. Pathways associated with sex hormone biosynthesis and sterol signaling are an understudied area in cnidarian biology. The objective of this study was to identify a suite of genes that can be linked to exposure of endocrine disruptors. Exaiptasia diaphana were exposed to nominal 20ppb concentrations of estradiol (E2), testosterone (T), cholesterol, oxybenzone (BP-3), or benzyl butyl phthalate (BBP) for 4 h. Eleven genes of interest (GOIs) were chosen from a previously generated EST library. The GOIs are 17β-hydroxysteroid dehydrogenases type 14 (17β HSD14) and type 12 (17β HSD12), Niemann-Pick C type 2 (NPC2), Equistatin (EI), Complement component C3 (C3), Cathepsin L (CTSL), Patched domain-containing protein 3 (PTCH3), Smoothened (SMO), Desert Hedgehog (DHH), Zinc finger protein GLI2 (GLI2), and Vitellogenin (VTG). These GOIs were selected because of functional associations with steroid hormone biosynthesis; cholesterol binding/transport; immunity; phagocytosis; or Hedgehog signaling. Quantitative Real-Time PCR quantified expression of GOIs. In silico modelling utilized protein structures from Protein Data Bank as well as creating protein structures with SWISS-MODEL. Results show transcription of steroidogenic enzymes, and cholesterol binding/transport proteins have similar transcription profiles for E2, T, and cholesterol treatments, but different profiles when BP-3 or BBP is present. C3 expression can differentiate between exposures to BP-3 versus BBP as well as exposure to cholesterol versus sex hormones. In silico modelling revealed all ligands (E2, T, cholesterol, BBP, and BP-3) have favorable binding affinities with 17β HSD14, 17β HSD12, NPC2, SMO, and PTCH proteins. VTG expression was down-regulated in the sterol treatments but up-regulated in BP-3 and BBP treatments. In summary, these eleven GOIs collectively generate unique transcriptional profiles capable of discriminating between the five chemical exposures used in this investigation. This suite of GOIs are candidate biomarkers for detecting transcriptional changes in steroidogenesis, gametogenesis, sterol transport, and Hedgehog signaling. Detection of disruptions in these pathways offers new insight into endocrine disruption in cnidarians.

Diversity of Plant Sterols Metabolism: The Impact on Human Health, Sport, and Accumulation of Contaminating Sterols

The way of plant sterols transformation and their benefits for humans is still a question under the massive continuing revision. In fact, there are no receptors for binding with sterols in mammalians. However, possible biotransformation to steroids that can be catalyzed by gastro-intestinal microflora, microbial cells in prebiotics or cytochromes system were repeatedly reported. Some products of sterols metabolization are capable to imitate resident human steroids and compete with them for the binding with corresponding receptors, thus affecting endocrine balance and entire physiology condition. There are also tremendous reports about the natural origination of mammalian steroid hormones in plants and corresponding receptors for their binding. Some investigations and reports warn about anabolic effect of sterols, however, there are many researchers who are reluctant to believe in and have strong opposing arguments. We encounter plant sterols everywhere: in food, in pharmacy, in cosmetics, but still know little about their diverse properties and, hence, their exact impact on our life. Most of our knowledge is limited to their cholesterol-lowering influence and protective effect against cardiovascular disease. However, the world of plant sterols is significantly wider if we consider the thousands of publications released over the past 10 years.

Possible overestimation of bisphenol analogues in municipal wastewater analyzed with GC-MS

This work for the first time showed that sulfated BPA could be directly analyzed as BPA with GC-MS after the derivatization with N,O-bis-(trimethylsilyl) trifluoroacetamide (BSTFA)+1% trimethylchlorosilane (TMCS), i.e. the deconjugation step was not necessary. This was because sulfated BPA indeed could be simultaneously deconjugated and derivatized to BPA derivative during derivatization, suggesting that any co-elution of BPA and sulfated BPA during sample extraction led to BPA overestimation in the GC-MS method with BSTFA +1% TMCS as the derivative reagent. Using BPA 4,4'-disulfates (BPA diS) as the pure standard, the co-elution phenomena of sulfated BPA was confirmed with two widely used elution solvents (i.e. methanol and ethyl acetate) or their mixed solutions with different ratios, which further suggested if only sulfated BPA existed in any wastewater sample, BPA was likely over-determined. To further confirm this finding, both influent and effluent samples collected from a local municipal wastewater treatment plant were analyzed, which clearly showed the overestimation of BPA in the two wastewaters due to co-existence of sulfated BPA in the wastewater samples. In addition to BPA, the results also showed the overestimation of other nine bisphenol analogues. As sulfated micropollutants including estrogens, androgens, phytoestrogens, etc., have been widely found in municipal wastewater, the overestimating phenomenon observed in this study may also be extended to determination of other micropollutants, which should be addressed in future.

Bisphenols emerging in Norwegian and Czech aquatic environments show transthyretin binding potency and other less-studied endocrine-disrupting activities

Bisphenols are increasingly recognized as environmental pollutants with endocrine-disrupting potential. Nonetheless, the study of environmental occurrence and some endocrine-disrupting activities of some bisphenols came widely into focus of research only recently. The aims of the present study were to: 1) determine the predominant bisphenols in Norwegian sewage sludge and sediment and in Czech surface waters, and 2) characterize the binding of bisphenols to a transport protein transthyretin (TTR) and their (anti-)thyroid, (anti-)progestagenic, and (anti-)androgenic activities. High-performance liquid chromatography with atmospheric pressure chemical ionization or photoionization coupled with high resolution mass spectrometry (HPLC-APCI/APPI-HRMS) and Chemically Activated LUciferase gene eXpression (CALUX) in vitro reporter gene bioassays were used to detect the target compounds and to determine endocrine-disrupting activities, respectively. Bisphenol A (BPA), 4,4'-bisphenol F (BPF), bisphenol S (BPS), and bisphenol E (BPE) were the most frequently found compounds in municipal sewage sludge. Furthermore, bisphenol TMC (BPTMC) and bisphenol AF (BPAF) frequently occurred in sediment and surface waters, respectively. BPA was the major contributor to Ʃ of bisphenols in Norwegian sewage sludge with exception of one sample where BPF predominated. We also monitored a few bisphenols in sediment but only BPTMC was found. BPA, BPAF and BPF were the dominant bisphenols in Czech surface waters. Some bisphenols have shown TTR binding potency (BPAF = BPF > BPA = BPE) and some have displayed the following endocrine-disrupting activities: anti-thyroid (BPAF), anti-progestagenic (BPTMC > BPA = BPAF), and anti-androgenic (BPAF > BPE > BPA > BPTMC > BPF > BPS). It is noteworthy that BPAF exhibited stronger or similarly potent endocrine-disrupting activities compared to BPA. Our results provide new insights into these less-studied endocrine-disrupting activities of environmentally relevant bisphenols and may be useful in prioritizing those compounds that deserve further attention in environmental monitoring and eco-toxicological research.

Environment-Friendly Removal Methods for Endocrine Disrupting Chemicals

In the past few decades, many emerging pollutants have been detected and monitored in different water sources because of their universal consumption and improper disposal. Among these, endocrine-disrupting chemicals (EDCs), a group of organic chemicals, have received global attention due to their estrogen effect, toxicity, persistence and bioaccumulation. For the removal of EDCs, conventional wastewater treatment methods include flocculation, precipitation, adsorption, etc. However, there are some limitations on these common methods. Herein, in order to enhance the public’s understanding of environmental EDCs, the definition of EDCs and the characteristics of several typical EDCs (physical and chemical properties, sources, usage, concentrations in the environment) are reviewed and summarized in this paper. In particular, the methods of EDC removal are reviewed, including the traditional methods of EDC removal, photocatalysis, biodegradation of EDCs and the latest research results of EDC removal. It is proposed that photocatalysis and biodegradation could be used as an environmentally friendly and efficient EDC removal technology. Photocatalytic technology could be one of the water treatment methods with the most potential, with great development prospects due to its high catalytic efficiency and low energy consumption. Biodegradation is expected to replace traditional water treatment methods and is also considered to be a highly promising method for efficient removal of EDCs. Besides, we summarize several photocatalysts with high catalytic activity and some fungi, bacteria and algae with strong biodegradability.

Assessment of the potential ecological risk of residual endocrine-disrupting chemicals from wastewater treatment plants

Residual chemicals discharged from wastewater treatment plants (WWTPs) and subsequent ecological risk are important in production safety when reuse of the effluent water occurs. Thus, this work provides an investigation of the occurrence and removal of dissolved Endocrine-disrupting chemicals (EDCs) in 38 WWTPs in Guangdong Province, China. The results indicate that EDCs are widely distributed in the investigated WWTPs, while nonylphenols (NPs) are the predominant chemical among the target EDCs, accounting for >98% of the concentration in the influent and >97% of the concentration in the effluent. Moreover, 4 main types of wastewater treatment processes (oxidation ditch, A2/O, conventional activated sludge and microaeration oxidation ditch followed by A2/O) were found to be inefficient for removing dissolved EDCs, with a mean removal rate of approximately 25%. The potential environmental risk was predicted for residual EDCs. Specifically, 17α-ethynylestradiol (EE2) was considered to be the most hazardous chemical among the target EDCs, with a median risk quotient (RQ) of 8.94. In addition, β-estradiol (E2) and estrone (E1) have median RQs of 1.14 and 0.27, and NPs have median RQs of 0.61 (algae), 0.37 (inverberate) and 0.25 (fish), respectively.

Pollutants delivered every day: Phthalates in plastic express packaging bags and their leaching potential

The rapid development of the express industry brings not only convenience but also environmental problems such as plastic wastes. In this study, we collected plastic express packaging bags from major express companies in China to investigate phthalates in them. Infrared spectra indicated that all these samples were made from polyethylene but with different carbonyl index (CI) values. Total phthalates (∑Phthalates) concentrations in these samples ranged from 11.16 to 309.70 μg g^-1. Di(2-ethylhexyl) phthalate, di-n-butyl phthalate, and di-isobutyl phthalate were predominant phthalates. The leaching amounts of ∑Phthalates after 48 h ranged from 181.44 to 5320.64 ng g^-1. The leaching amounts of ∑Phthalates significantly positively related to ∑Phthalates concentrations of samples, while the leaching ratios presented opposite trends. Concentrations and leaching amounts of ∑Phthalates and major phthalates were significantly higher in samples from high CI value company group than those from low CI value company group. The results of our study indicate that plastic express packaging bags could be a critical source of phthalates. The involving of recycled plastics during the manufacture of plastic express packaging bags may influence the content and composition of phthalates in them and also increase the releasing risk of phthalates.

Ecofriendly laccases treatment to challenge micropollutants issue in municipal wastewaters

In this study, a multidisciplinary approach investigated the enzymatic degradation of micropollutants in real, not modified, municipal wastewaters of a plant located in Italy. Stir Bar Sorptive Extraction combined to Gas Chromatography-Mass Spectrometric detection (SBSE-GC-MS) was applied to profile targeted pollutants in wastewaters collected after the primary sedimentation (W1) and the final effluent (W2). Fifteen compounds were detected at ng/L - μg/L, including pesticides, personal care products (PCPs) and drugs. The most abundant micropollutants were bis(2-ethylhexyl) phthalate, diethyl phthalate and ketoprofen. Laccases of Trametes pubescens MUT 2400 were very active against all the target micropollutants: except few cases, their concentration was reduced more than 60%. Chemical analysis and environmental risk do not always come together. To verify whether the treated wastewaters can represent a stressor for the aquatic ecosystem, toxicity was also evaluated. Raphidocelis subcapitata and Lepidium sativum tests showed a clear ecotoxicity reduction, even though they did not evenly respond. Two in vitro tests (E-screen test and MELN assay) were used to evaluate the estrogenic activity. Treatments already operating in the plant (e.g. activated sludge) partially reduced the estradiol equivalent concentration, and it was almost negligible after the laccases treatment. The results of this study suggest that laccases of T. pubescens are promising biocatalysts for the micropollutants transformation in wastewaters and surface waters.

Free and conjugated estrogens detections in drainage tiles and wells beneath fields receiving swine manure slurry

Although livestock manure, such as from swine (Sus scrofa domestica), have high capacity to introduce endocrine-disrupting free estrogens into the environment, the frequency of estrogen detections from reconnaissance studies suggest that these compounds are ubiquitous in the environment, perhaps resulting from historic manure inputs (e.g. cattle grazing residues, undocumented historic manure applications) or uncontrolled natural sources. Compared to free estrogens, conjugates of estrogens are innocuous but have greater mobility in the environment. Estrogen conjugates can also hydrolyze to re-form the potent free estrogens. The objective of this study was to identify the transport of free and conjugated estrogens to subsurface tile drains and groundwater beneath fields treated with swine manure slurry. Three field treatments were established, two receiving swine lagoon manure slurry and one with none. Manure slurry was injected into soils at a shallow depth (∼8 cm) and water samples from tile drains and shallow wells were sampled periodically for three years. Glucuronide and sulfate conjugates of 17β-estradiol (E2) and estrone (E1) were the only estrogen compounds detected in the tile drains (total detects = 31; 5% detection frequency; conc. range = 3.9-23.1 ng L^-1), indicating the important role conjugates played in the mobility of estrogens. Free estrogens and estrogen conjugates were more frequently detected in the wells compared to the tile drains (total detects = 70; 11% detection frequency; conc. range = 4.0-1.6 × 10³ ng L^-1). No correlations were found between estrogen compound detections and dissolved or colloidal organic carbon (OC) fractions or other water quality parameters. Estrogenic compounds were detected beneath both manure treated and non-treated plots; furthermore, the total potential estrogenic equivalents (i.e. estrogenicity of hydrolyzed conjugates + free estrogens) were similar between treated and non-treated plots.

Human exposure of bisphenol A and its analogues: understandings from human urinary excretion data and wastewater-based epidemiology

This work evaluated human exposure to bisphenol A (BPA) and its analogues based on human urinary excretion data and wastewater-based epidemiology (WBE). The results showed that the world's average human daily intake ranked from high to low is in order of bisphenol A (BPA), bisphenol F (BPF), bisphenol S (BPS), bisphenol P (BPP), bisphenol AP (BPAP), bisphenol B (BPB), bisphenol Z (BPZ), and bisphenol AF (BPAF), and their corresponding human daily intakes are 2.53, 0.68, 0.60, 0.41, 0.36, 0.29, 0.24, and 0.06 μg/p/day, respectively. BPA is clearly the dominant bisphenol for human exposure. However, the results also showed that humans have been widely exposed to BPA analogues as well. Many BPA analogues showed similar estrogenic activities to those of BPA; therefore, the adverse effects of BPA and its analogues on humans should be comprehensively evaluated. The nominal exposure levels obtained based on wastewater-based epidemiology ranked high to low are in order of BPA (513.73 μg/p/day), BPF (10.20 μg/p/day), BPS (5.21 μg/p/day), BPP (1.15 μg/p/day), BPZ (0.66 μg/p/day), BPB (0.61 μg/p/day), BPAF (0.58 μg/p/day), and BPAP (0.35 μg/p/day). The world's human average daily intakes of BPA and its analogues are only 0.5-47.9% of the intakes of their corresponding human nominal exposures. This study suggests that other sources rather human excretions are important origins in municipal wastewater, which indicates that the WBE method based on parent compounds is inappropriate for evaluations of human daily intakes of BPA and its analogues, neither for other industrial compounds that have multiple important sources. Three main important sources of BPA and its analogues in municipal wastewater are likely effluents of industrial wastewater, discharges of hospital wastewater, and landfill leachates. To decrease discharges of BPA and its analogues to the natural environment, any mixing of industrial and hospital wastewater as well as landfill leachates in municipal wastewater is not favorable.

Occurrence and fate of androgens in municipal wastewater treatment plants in China

Public concerns about potential ecological risks of androgens discharged to the environment through wastewater treatment plants (WWTPs) has resulted in an increased interest regarding the occurrence and fate of androgens in WWTPs. In this study, the occurrence and removal of eight androgens from 12 municipal WWTPs distributed in eleven cities in China were investigated. The composition profiles of eight androgens in influent, effluent, and excess sludge were studied. Multiple factor analyses were performed to reveal the factors affecting the distribution of androgens in WWTP influent. Results showed similar composition profiles of androgens in the studied WWTPs, with androsterone and dehydroepiandrosterone confirmed as the dominant androgens. The distributions of androgens in WWTP influent were related to the chemical oxygen demand in influent and the gross domestic product (GDP) of WWTP-associated cities. The target androgens have high aqueous removal rates, with a mean removal rate of >90%. Additionally, the behaviors of androgens were evaluated by mass balance along anaerobic-anoxic-oxic (AAO) processes in a WWTP, in which many of the androgens were eliminated mainly in the anaerobic tank. Further, 15 biotransformation products of testosterone were identified under anaerobic, anoxic, and aerobic sludge, respectively. Based on these metabolites, a general biotransformation pathway of testosterone under anaerobic, anoxic, and aerobic sludge is presented.

Assessing the risk of utilizing tidal coastal wetlands for wastewater management

Coastal tidal wetlands are well recognized for the key ecosystem services they provide such as flood protection, water quality improvement, and carbon sequestration. In the southeastern United States, some communities rely on coastal wetlands for the management of secondarily treated effluents in forested and emergent wetlands. Advocates for this practice have argued that wetlands can assimilate nitrogen from wastewater, which can improve cypress-tupelo swamp productivity, and enhance marsh accretion rates to mitigate the effects of sea level rise. In contrast, evolving research on coastal wetlands and the environmental impacts of wastewater treatment pose new questions about the potential risks introduced by this practice. This review seeks to: (1) assess current research on plant productivity in fertilized coastal wetlands; (2) highlight the occurrence and fate of pharmaceuticals and personal care products (PPCPs) in municipal wastewater operations; and (3) identify knowledge gaps. Nutrient additions via wastewater augmented aboveground productivity, but decreased belowground productivity and root-to-shoot ratios. Removal efficiencies of some PPCPs by coastal wetlands have been substantial (75% - 99%), but most remain unevaluated. Furthermore, their fate and effect on local ecosystem function and biogeochemical processes remain in question. This review demonstrates that there is more research needed at both local and watershed scales to evaluate how these risk factors impact ecosystem integrity and to better understand the tradeoffs with this wastewater management practice.

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 μg 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 μg L^-1. Nevertheless, analysis of digested sludge from sites which received these elevated BPA levels revealed average concentrations of 4.6 ± 0.3 and 38.7 ± 5.4 μg 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.

Cyanobacterial blooms act as sink and source of endocrine disruptors in the third largest freshwater lake in China

Cyanobacterial blooms are of global concern due to the multiple harmful risks they pose towards aquatic ecosystem and human health. However, information on the fate of organic pollutants mediated by cyanobacterial blooms in eutrophic water remains elusive. In the present study, endocrine disruptive potentials of phytoplankton samples were evaluated throughout a year-long surveillance in a large and eutrophic freshwater lake. Severe cyanobacterial blooms persisted during our sampling campaigns. Estrogenic agonistic, anti-estrogenic, anti-androgenic, and anti-glucocorticogenic effects were observed in the phytoplankton samples using in vitro reporter gene bioassays. 27 endocrine disrupting chemicals (EDCs) of different modes of action were detected in the samples via UPLC-MS/MS system. Results from mass balance analysis indicated that the measured estrogenic activities were greater than the predicted estrogenic potencies from chemical analysis, demonstrating that chemical analysis of targeted EDCs is unable to fully explain the compounds responsible for the observed estrogenicities. Results from Spearman's correlation analysis concluded that the concentrations of ten EDCs in phytoplankton samples were negatively correlated with cyanobacterial biomass, suggesting the potential occurrence of biomass bio-dilution effects of EDCs due to the huge biomass of cyanobacteria during bloom seasons. The present study provided complementary information about the potential endocrine disruptive risks of cyanobacterial blooms, which is important for understanding and regulating EDCs in eutrophic lakes.

Endocrine-disrupting compounds in the Xiangjiang River of China: Spatio-temporal distribution, source apportionment, and risk assessment

Endocrine-disrupting compounds (EDCs) were seasonally investigated in the surface water of the Xiangjiang River (south China) in order to understand their spatio-temporal distribution, source apportionment, and ecological risks. The occurrence of 21 EDCs were determined with liquid chromatography-tandem mass spectrometry in the water samples collected along the river over four seasons, and the results were statistically analyzed. The concentrations of progestagens, androgens, estrogens ranged from not detected (ND) to 98.3 ng L^-1; while the concentrations of alkylphenols ranged from 0.8 to 3.1 × 10³ ng L^-1; and that of caffeine ranged from 0.1 to 49.8 ng L^-1. The detection frequencies of bisphenol A, 4-tert-octylphenol, 4-n-nonylphenol, estrone, and 17β-estradiol were 95-100% during the four sampling campaigns. The seasonal and spatial variation trend of EDCs in the Xiangjiang River was noticeable. The concentration of EDCs in Yueyang section (downstream) was the highest in winter, while the concentration in Yongzhou (upstream) section was the lowest in spring. The concentration of EDCs in the Xiangjiang River was significantly correlated with the levels of the total organic carbon, water temperature, and dissolved oxygen. Source analysis indicated that untreated sewage was the major source of EDCs. Furthermore, the potential risks of EDCs in the surface water to aquatic organisms were assessed with the risk quotient method (European Commission, 2003), and the results indicated the highest ecological risk of 17β-estradiol in the Xiangjiang River.

Quantification of selected steroid hormones (17β-Estradiol and 17α-Ethynylestradiol) in wastewater treatment plants in Klang Valley (Malaysia)

Steroid estrogens, such as 17β-estradiol (E₂) and 17α-ethynylestradiol (EE₂) are potent and were categorized as "Watch List" in Directive 2013/39/EU because of their potential risks to aquatic environment. Commercialized enzyme-linked immunosorbent assay (ELISA) kits have been used to quantify steroid estrogens in wastewater samples due to their simplicity, rapid, cost-effectiveness, and validated assays. Hence, this study aims to determine the occurrence and removal of steroid hormones in Malaysian wastewater treatment plants (WWTPs) by ELISA, to identify the association of removal efficiency (E₂ and EE₂) with respect to WWTPs operating conditions, and to assess the potential risks of steroid estrogens to aquatic environment and human. Results showed E₂ concentration ranged from 88.2 ± 7.0 ng/L to 93.9 ± 6.9 ng/L in influent and 35.1 ± 17.3 ng/L to 85.2 ± 7.6 ng/L in effluent, with removal of 6.4%-63.0%. The EE₂ concentration ranged from 0.2 ± 0.2 ng/L to 4.9 ± 6.3 ng/L in influent and 0.02 ± 0.03 ng/L to 1.0 ± 0.8 ng/L in effluent, with removal of 28.3-99.3%. There is a correlation between EE₂ removal with total suspended solid (TSS) and oxidation reduction potential (ORP), and was statistically significant. Despite the calculated estrogenic activity for E₂ and EE₂ was relatively high, dilution effects could lower estrogenic response to aquatic environment. Besides, these six selected WWTPs have cumulative RQ values below the allowable limit, except WWTP 1. Relatively high precipitation (129-218 mm) could further dilute estrogens concentration in the receiving river. These outputs can be used as quantitative information for evaluating the occurrence and removal of steroid estrogens in Malaysian WWTPs.

A National Wastewater Monitoring Program for a better understanding of public health: A case study using the Australian Census

Wastewater contains a large range of biological and chemical markers of human activity and exposures. Through systematic collection and analysis of these markers within wastewater samples it is possible to measure the public health of whole populations. The analysis of effluent and biosolids can also be used to understand the release of chemicals from wastewater treatment plants into the environment. Wastewater analysis and comparison with catchment specific data (e.g. demographics) however remains largely unexplored. This manuscript describes a national wastewater monitoring study that combines influent, effluent and biosolids sampling with the Australian Census. An archiving program allows estimation of per capita exposure to and consumption of chemicals, public health information, as well as per capita release of chemicals into the environment. The paper discusses the study concept, critical steps in setting up a coordinated national approach and key logistical and other considerations with a focus on lessons learnt and future applications. The unique combination of archived samples, analytical data and associated census-derived population data will provide a baseline dataset that has wide and potentially increasing applications across many disciplines that include public health, epidemiology, criminology, toxicology and sociology.

An overview of phthalate acid ester pollution in China over the last decade: Environmental occurrence and human exposure

The toxicity and bioaccumulation potential of phthalate acid esters (PAEs) make their impact on the environment a matter of considerable concern. Due to China's recent economic development and population growth, it has become one of the largest manufacturers and consumers of PAEs, with an associated contamination threat to several environmental compartments. The aim of this overview is to present a systematic account of PAE occurrence in various environmental media in China in the last decade, including the air, surface water, sediments, soil, sewage, and sludge; human exposure to PAEs is also evaluated. This reveals a location-dependence that can be attributed to regional differences in economic and industrial development as well as specific geographic location. A need for further study into the transportation and transformation behavior of PAEs in different environmental media and into PAE control technologies is identified, as a means of effectively assessing potential ecological and health risks.

Wastewater recycling in Antarctica: Performance assessment of an advanced water treatment plant in removing trace organic chemicals

The Australian Antarctic Division (AAD) operates Australia's Davis Station in the Antarctic. In 2005, Davis Station's wastewater treatment plant failed and since then untreated, macerated effluent has been discharged to the ocean. The objectives of this study were to determine whether an advanced water treatment plant (AWTP) commissioned by the AAD and featuring a multi-barrier process involving ozonation, ceramic microfiltration, biologically activated carbon filtration, reverse osmosis, ultraviolet disinfection and chlorination was capable of producing potable water and a non-toxic brine concentrate that can be discharged with minimal environmental impact. The AWTP was tested using water from a municipal wastewater treatment plant in Tasmania, Australia. We used spot water and passive sampling combined with two multi-residue chromatographic-mass spectrometric methods and a range of recombinant receptor-reporter gene bioassays to screen trace organic chemicals (TrOCs), toxicity and receptor activity in the Feed water, in the environmental discharge (reject water), and product water from the AWTP for six months during 2014-15, and then again for three months in 2016. Across the two surveys we unambiguously detected 109 different TrOCs in the feed water, 39 chemicals in the reject water, and 34 chemicals in the product water. Sample toxicity and receptor activity in the feed water samples was almost totally removed in both testing periods, confirming that the vast majority of the receptor active TrOCs were removed by the treatment process. All the NDMA entering the AWTP in the feed and/or produced in the plant (typically < 50 ng/L), was retained into the reject water with no NDMA observed in the product water. In conclusion, the AWTP was working to design, and releases of TrOCs at the concentrations observed in this study would be unlikely cause adverse effects on populations of aquatic organisms in the receiving environment or users of the potable product water.

Occurrence and fate of emerging contaminants in municipal wastewater treatment plants from different geographical regions-a review

Emerging contaminants, such as antibiotics, pharmaceuticals, personal care products, hormones, and artificial sweeteners, are recognized as new classes of water contaminants due to their proven or potential adverse effects on aquatic ecosystems and human health. This review provides comprehensive data on the occurrence of 60 emerging contaminants (ECs) in influent, treated effluent, sludge, and biosolids in wastewater treatment plants (WWTPs). In particular, data on the occurrence of ECs in the influents and effluents of WWTPs are systematically summarized and categorized according to geographical regions (Asia, Europe, and North America). The occurrence patterns of ECs in raw influent and treated effluents of WWTPs between geographical regions were compared and evaluated. Concentrations of most ECs in raw influent in Asian region tend to be higher than those in European and North American countries. Many antibiotics were detected in the influents and effluents of WWTPs at concentrations close to or exceeding the predicted no-effect concentrations (PNECs) for resistance selection. The efficacy of EC removal by sorption and biodegradation during wastewater treatment processes are discussed in light of kinetics and parameters, such as sorption coefficients (K_d) and biodegradation constants (k_biol), and physicochemical properties (i.e. log K_ow and pK_a). Commonly used sampling and monitoring strategies are critically reviewed. Analytical research needs are identified, and novel investigative approaches for future monitoring studies are proposed.

Changes in estrogenicity and micropollutant concentrations across unit processes in a biological wastewater treatment system

The behavior of 10 micropollutants, i.e. four estrogens (estrone, 17β-estradiol, estriol, 17α-ethynylestradiol), carbamazepine (CBZ), sulfamethoxazole (SMX), triclosan, oxybenzone, 4-nonylphenol, and bisphenol A, was investigated in a typical domestic wastewater treatment plant. LC-MS and yeast estrogen screen bioassay were used to study the changes in micropollutants and estrogenicity across unit processes in the treatment system. Primary treatment via sedimentation showed that only 4-nonylphenol was removed, but led to no significant change in estrogenicity. Secondary treatment by the biological nitrification-dentrification process showed complete removal of oxybenzone and partial removal of the estrogens, which led to a decrease in estrogenic activity from 80 to 48 ng/L as estradiol equivalent (EEq). Ultraviolet treatment completely degraded the estrogens and triclosan, but failed to lower the concentrations of bisphenol A, SMX, and CBZ; a decrease in estrogenic activity from 48 to 5 ng/L EEq across the unit, a value that was only slightly larger than the observed EEq of 1 ng/L for the deionized control. Similarly, the anaerobic digestion of sludge completely degraded estrogens, oxybenzone, and SMX, but had no impact on bisphenol A, triclosan, and CBZ. The study emphasises the need to complement chemical analyses with estrogenic bioassays to evaluate the efficacy of waste water treatment plants.

4-Phenoxyphenol-Functionalized Reduced Graphene Oxide Nanosheets: A Metal-Free Fenton-Like Catalyst for Pollutant Destruction

Metal-containing Fenton catalysts have been widely investigated. Here, we report for the first time a highly effective stable metal-free Fenton-like catalyst with dual reaction centers consisting of 4-phenoxyphenol-functionalized reduced graphene oxide nanosheets (POP-rGO NSs) prepared through surface complexation and copolymerization. Experimental and theoretical studies verified that dual reaction centers are formed on the C-O-C bridge of POP-rGO NSs. The electron-rich center around O is responsible for the efficient reduction of H₂O₂ to ^•OH, while the electron-poor center around C captures electrons from the adsorbed pollutants and diverts them to the electron-rich area via the C-O-C bridge. By these processes, pollutants are degraded and mineralized quickly in a wide pH range, and a higher H₂O₂ utilization efficiency is achieved. Our findings address the problems of the classical Fenton reaction and are useful for the development of efficient Fenton-like catalysts using organic polymers for different fields.

Removal of organic micropollutants in waste stabilisation ponds: A review

As climate change and water scarcity continue to be of concern, reuse of treated wastewater is an important water management strategy in many parts of the world, particularly in developing countries and remote communities. Many countries, especially in remote regional areas, use waste stabilisation ponds (WSPs) to treat domestic wastewater for a variety of end uses, including using the treated wastewater for irrigation of public spaces (e.g. parks and ovals) or for crop irrigation. Thus, it is vital that the resulting effluent meets the required quality for beneficial reuse. In this paper, both the performance of WSPs in the removal of organic micropollutants, and the mechanisms of removal, are reviewed. The performance of WSPs in the removal of organic micropollutants was found to be highly variable and influenced by many factors, such as the type and configuration of the ponds, the operational parameters of the treatment plant, the wastewater quality, environmental factors (e.g. sunlight, temperature, redox conditions and pH) and the characteristics of the pollutant. The removal of organic micropollutants from WSPs has been attributed to biodegradation, photodegradation and sorption processes, the majority of which occur in the initial treatment stages (e.g. in the anaerobic or facultative ponds). Out of the many hundreds of organic micropollutants identified in wastewater, only a limited number (40) have been studied in WSPs, with the majority of these pollutants being pharmaceuticals, personal care products and endocrine disrupting compounds. Thus, future research on the fate of organic micropollutants in WSPs should encompass a broader range of micropollutants and include emerging organic pollutants, such as illicit drugs and perfluorinated compounds. Further research is also needed on the formation and toxicity of transformation products from organic micropollutants in WSPs, since the transformation products of some organic micropollutants can be more toxic than the parent compound. Combining other wastewater treatment processes with WSPs for removal of recalcitrant organic micropollutants should also be considered.

Identification of Unknown Antiandrogenic Compounds in Surface Waters by Effect-Directed Analysis (EDA) Using a Parallel Fractionation Approach

Among all the nuclear-receptor mediated endocrine disruptive effects, antiandrogenicity is frequently observed in aquatic environments and may pose a risk to aquatic organisms. Linking these effects to responsible chemicals is challenging and a great share of antiandrogenic activity detected in the environment has not been explained yet. To identify drivers of this effect at a hot spot of antiandrogenicity in the German river Holtemme, we applied effect-directed analysis (EDA) including a parallel fractionation approach, a downscaled luciferase reporter gene cell-based anti-AR-CALUX assay and LC-HRMS/MS nontarget screening. We identified and confirmed the highly potent antiandrogen 4-methyl-7-diethylaminocoumarin (C47) and two derivatives in the active fractions. The relative potency of C47 to the reference compound flutamide was over 5.2, whereas the derivatives were less potent. C47 was detected at a concentration of 13.7 μg/L, equal to 71.4 μg flutamide equivalents per liter (FEq/L) in the nonconcentrated water extract that was posing an antiandrogenic activity equal to 45.5 (±13.7 SD) FEq/L. Thus, C47 was quantitatively confirmed as the major cause of the measured effect in vitro. Finally, the antiandrogenic activity of C47 and one derivate was confirmed in vivo in spiggin-gfp Medaka. An endocrine disrupting effect of C47 was observed already at the concentration equal to the concentration in the nonconcentrated water extract, underlining the high risk posed by this compound to the aquatic ecosystem. This is of some concern since C47 is used in a number of consumer products indicating environmental as well as human exposure.

Environmental pollution affects molecular and biochemical responses during gonadal maturation of Astyanax fasciatus (Teleostei: Characiformes: Characidae)

Endocrine disrupting compounds (EDCs) have the potential to alter fish reproduction at various levels of organization. The aim of this study was to assess the impact of a natural environment with heavily anthropogenic influence on the physiological processes involved in reproduction in the freshwater fish lambari (Astyanax fasciatus) using different biomarkers. Adult males and females were collected in different seasons from two distinct sites in the same watershed: Ponte Nova Reservoir (PN) considered a pristine or small anthropogenic influence reference point; and Billings Reservoir (Bil), subjected to a large anthropogenic impact. Biological indices, such as hepatosomatic index and gonadosomatic index (GSI), gonadal histomorphology, fecundity, and biomarkers such as plasma levels of estradiol (E2) as well as hepatic gene expression of its alfa nuclear receptor (ERα), were analyzed. Hepatic vitellogenin (VTG) gene expression was evaluated in both sexes, as an indicator of xenoestrogen exposure. Females collected at PN presented a typical annual variation reflected in GSI, whereas for those sampled at Bil the index did not change through the seasons. The higher concentration of E2 in males collected at Bil during spring/2013, together with the detection of VTG gene expression, suggest the presence of EDCs in the water. These EDCs may have also influenced fecundity of females from Bil, which was higher during winter and spring/2013. Gene expression of ERα and ovarian morphology did not differ between fish from both sites. Water conditions from Bil reservoir impacted by anthropic activity clearly interfered mainly with biomarkers of biological effect such as plasma E2 levels and absolute and relative fecundity, but also altered biomarkers of exposure as VTG gene expression. These facts support the notion that waterborne EDCs are capable of causing estrogenic activity in A. fasciatus.

Mathematical modeling for estrogenic activity prediction of 17β-estradiol and 17α-ethynylestradiol mixtures in wastewater treatment plants effluent

Steroid estrogens such as 17β-Estradiol (E₂) and 17α-Ethynylestradiol (EE₂) are highly potent estrogens that widely detected in environmental samples. Mathematical modelling such as concentration addition (CA) and estradiol equivalent concentration (EEQ) models are usually associated with measuring techniques to assess risk, predict the mixture response and evaluate the estrogenic activity of mixture. Wastewater has played a crucial role because wastewater treatment plant (WWTP) is the major sources of estrogenic activity in aquatic environment. The aims of this is to determine E₂ and EE₂ concentrations in six WWTPs effluent, to predict the estrogenic activity of the WWTPs effluent using CA and EEQ models where lastly the effectiveness of two models is evaluated. Results showed that all the six WWTPs effluent had relative high E₂ concentration (35.1-85.2 ng/L) compared to EE₂ (0.02-1.0 ng/L). The estrogenic activity predicted by CA model was similar among the six WWTPs (105.4 ng/L), due to the similarity of individual dose potency ratio calculated by respective WWTPs. The predicted total EEQ was ranged from 35.1 EEQ-ng/L to 85.3 EEQ-ng/L, explained by high E₂ concentration in WWTPs effluent and E₂ EEF value that standardized to 1.0 μg/L. The CA model is more effective than EEQ model in estrogenic activity prediction because EEQ model used less data and causes disassociation from the predicted behavior. Although both models predicted relative high estrogenic activity in WWTPs effluent, dilution effects in receiving river may lower the estrogenic response to aquatic inhabitants.

Occurrence of phthalates in aquatic environment and their removal during wastewater treatment processes: a review

Phthalates are plasticizers and are concerned environmental endocrine-disrupting compounds. Due to their extensive usage in plastic manufacturing and personal care products as well as the potential to leach out from these products, phthalates have been detected in various aquatic environments including drinking water, groundwater, surface water, and wastewater. The primary source of their environmental occurrence is the discharge of phthalate-laden wastewater and sludge. This review focuses on recent knowledge on the occurrence of phthalate in different aquatic environments and their fate in conventional and advanced wastewater treatment processes. This review also summarizes recent advances in biological removal and degradation mechanisms of phthalates, identifies knowledge gaps, and suggests future research directions.

Sources and levels of endocrine disrupting compounds (EDCs) in Kuwait's coastal areas

The sources and levels of endocrine disrupting compounds in Kuwait's coastal areas were investigated. Phthalates, alkylphenols and estrogens were measured in the inflows and outflows of three sewage treatment plants as well as in the seawater and sediments from the sewage impacted coastal areas. Phthalate levels in the inflow of the treatment plants ranged from 8.9 to 78.3μg/l; alkylphenols from 0.7 to 279ng/l and estrogens from 30 to 368ng/l. On average, the treatment plants removed about 80% of these compounds. The outflows, however, contained significant levels of all three classes of compounds. The seawater from the sewage impacted area also contained detectable levels of these compounds. Sediment samples from these locations contained elevated levels of phthalates (ranging from 2145 to 15,722μg/kg) and lower levels of alkylphenols (ranging from 2.49 to 15.14μg/kg) and estrogens (ranging from 4.1 to 214μg/kg, dry wt.).

Sources, mechanisms, and fate of steroid estrogens in wastewater treatment plants: a mini review

Steroid estrogens, such as estrone (E₁), 17β-estradiol (E₂), estriol (E₃), and 17α-ethinylestradiol (EE₂), are natural and synthetic hormones released into the environment through incomplete sewage discharge. This review focuses on the sources of steroid estrogens in wastewater treatment plants (WWTPs). The mechanisms and fate of steroid estrogens throughout the entire wastewater treatment system are also discussed, and relevant information on regulatory aspects is given. Municipal, pharmaceutical industry, and hospitals are the main sources of steroid estrogens that enter WWTPs. A typical WWTP comprises primary, secondary, and tertiary treatment units. Sorption and biodegradation are the main mechanisms for removal of steroid estrogens from WWTPs. The fate of steroid estrogens in WWTPs depends on the types of wastewater treatment systems. Steroid estrogens in the primary treatment unit are removed by sorption onto primary sludge, followed by sorption onto micro-flocs and biodegradation by microbes in the secondary treatment unit. Tertiary treatment employs nitrification, chlorination, or UV disinfection to improve the quality of the secondary effluent. Activated sludge treatment systems for steroid estrogens exhibit a removal efficiency of up to 100%, which is higher than that of the trickling filter treatment system (up to 75%). Moreover, the removal efficiency of advance treatment systems exceeds 90%. Regulatory aspects related to steroid estrogens are established, especially in the European Union. Japan is the only Asian country that implements a screening program and is actively involved in endocrine disruptor testing and assessment. This review improves our understanding of steroid estrogens in WWTPs, proposes main areas to be improved, and provides current knowledge on steroid estrogens in WWTPs for sustainable development.

Comparative assessment of phthalate removal and risk in biological wastewater treatment systems of developing countries and small communities

Phthalates are widely used in plastic and personnel care products. Being non-steroid endocrine disrupting compounds, their exposure have toxic effects on aquatic life and human health. The aim of this study was a comparative assessment of their fate and risk in full scale wastewater treatment along with influence of seasonal variations. Four priority phthalates, Diethylphthalate (DEP), Dibutylphthalate (DBP), Benzylbutyl phthalate (BBP) and Diethylhexyl phthalate (DEHP) were chosen for this study and wastewater treatment plants investigated were designed as nutrient removal based sequencing batch reactor (SBR), conventional activated sludge process (ASP) and up flow anaerobic sludge blanket (UASB) with polishing pond. Results showed that the main removal mechanism of phthalates was biotransformation with removal contribution of 74% in SBR, 65% in conventional ASP and 37% in UASB. Overall removal of phthalates was maximum in the treatment combination of UASB and pond (83%) followed by SBR (80%) and conventional ASP (74%). Seasonal influences on occurrence, removal and risk of these phthalates were also studied. The concentration of DEP, DBP and DEHP in untreated wastewater increased by 2, 7 and 2μg/L, respectively in summer. However in sludge, only large molecular weight phthalates BBP and DEHP increased in winter by 3mg/kg and 12mg/kg, respectively. Seasonal variations in removal of phthalates were discrepant in each process with better removal during summer. Risk assessment of phthalates to aquatic life showed that there is no potential risk of DEP, DBP and BBP from effluents of treatment plants however risk quotient of DEHP was in the range of 27-73 in both seasons which indicate probable risk to aquatic organisms. Phthalate risk to human beings estimated by daily intake of phthalates was in the range of 0.3±0.1 to 20±0.7ng/kg/d and far below their respective reference dosages, demonstrating the potential of these treatment plants to reduce the risk of phthalates.

Probabilistic ecological risk assessment of effluent toxicity of a wastewater reclamation plant based on process modeling

The growing use of reclaimed wastewater for environmental purposes such as stream flow augmentation requires comprehensive ecological risk assessment and management. This study applied a system analysis approach, regarding a wastewater reclamation plant (WRP) and its recipient water body as a whole system, and assessed the ecological risk of the recipient water body caused by the WRP effluent. Instead of specific contaminants, two toxicity indicators, i.e. genotoxicity and estrogenicity, were selected to directly measure the biological effects of all bio-available contaminants in the reclaimed wastewater, as well as characterize the ecological risk of the recipient water. A series of physically based models were developed to simulate the toxicity indicators in a WRP through a typical reclamation process, including ultrafiltration, ozonation, and chlorination. After being validated against the field monitoring data from a full-scale WRP in Beijing, the models were applied to simulate the probability distribution of effluent toxicity of the WRP through Latin Hypercube Sampling to account for the variability of influent toxicity and operation conditions. The simulated effluent toxicity was then used to derive the predicted environmental concentration (PEC) in the recipient stream, considering the variations of the toxicity and flow of the upstream inflow as well. The ratio of the PEC of each toxicity indicator to its corresponding predicted no-effect concentration was finally used for the probabilistic ecological risk assessment. Regional sensitivity analysis was also performed with the developed models to identify the critical control variables and strategies for ecological risk management.

No evidence of exposure to environmental estrogens in two feral fish species sampled from the Yarra River, Australia: A comparison with Northern Hemisphere studies

Environmental estrogens originate from a variety of sources including sewage treatment plant (STP) effluents and adverse physiological effects (endocrine disruption) have been observed in several fish species sampled downstream of STP discharges. In this study we examined common carp (Cyprinus carpio) and roach (Rutilis rutilis) for signs of exposure to environmental estrogens in the iconic Yarra River, Melbourne, Australia. The Yarra River flows through the city of Melbourne and more than 2 million people live within the catchment. Two STPs discharge water into the Yarra River within the middle reaches, and the areas immediately downstream of these discharge locations were the focus of this study. Carp and roach were chosen as test species since both have been utilised extensively for endocrine disruption research throughout Europe, North America and Asia, and data from various international studies was used for comparison with the results of the present study. Neither species showed evidence of exposure to environmental estrogens, with no elevation of plasma vitellogenin levels in males and no incidence of intersex gonads. Most physiological endpoints in both species from this study were within ranges reported in carp and roach from reference sites in other studies, however some degenerative histological changes in both male and female gonads were observed. Surface water samples showed no estrogenic activity (measured by the yeast-estrogen screen, YES), but did display strong anti-estrogenic and weak androgenic activity (measured by the yeast-androgen screen, YAS). Whilst the results show no evidence of impacts from environmental estrogens in the Yarra River, the presence of both anti-estrogenic and androgenic activity in water samples, as well as some gonadal changes in carp is concerning and indicates that our focus needs to broaden, in order to look for biological impacts in resident fauna that might be due to environmental pollutants other than environmental estrogens.

The impact of variations of influent loading on the efficacy of an advanced tertiary sewage treatment plant to remove endocrine disrupting chemicals

The impact of changes in influent load on the removal of endocrine disrupting chemicals (EDCs) by sewage treatment has not been fully characterised. This study assessed the efficacy of an advanced tertiary sewage treatment plant (STP) to remove EDCs during normal and peak flow events of sewage influent using trace chemical analysis of selected EDCs and four estrogenic in vitro bioassays. During the summer holiday season, influent volume increased by 68%, nutrient concentrations by at least 26% and hydraulic retention time was reduced by 40% compared with base flow conditions. Despite these pressures on the treatment system the concentrations and mass loading of estrone, 17β-estradiol, estriol, Bisphenol A, 4-t-octylphenol and technical nonylphenol were not significantly higher (p>0.05) during the peak flow conditions compared with base flow conditions. Chemical analysis and in vitro bioassays showed that the efficacy of the STP in removing EDCs was not affected by the different loadings between baseline and peak flow regimes. This study demonstrates that large flow variations within the design capacity of advanced multi-stage STPs should not reduce the removal efficacy of EDCs.

Altered bioenergetics and developmental effects in striped marsh frog (Limnodynastes peronii) tadpoles exposed to UV treated sewage

Effectively treating domestic wastewater so that it can be safely discharged or reused is critical for maintaining the integrity of freshwater resources, and for protecting the health of animals that rely on these systems. Amphibians are currently facing widespread population declines, so there is a particularly urgent need to investigate exposure scenarios that might result in weakened amphibian populations. Domestic sewage has received little attention as a possible factor that could influence the survival, growth and development, or general health of amphibians. However, wastewater reuse for crop irrigation and other purposes is increasing and holding ponds and constructed wetlands exist at many wastewater treatment facilities, introducing conceivable pathways that could result in the exposure of amphibians to treated wastewater. We exposed developing striped marsh frog (Limnodynastes peronii) tadpoles, to control water and 12.5, 25, 50 and 100% UV treated domestic sewage, and quantified effects on growth and development, hepatic energy reserves, and enzymatic pathways associated with detoxification and oxidative stress. Growth and development were accelerated and relative liver size was increased in exposed animals. The exposure resulted in an apparently hormetic increase in hepatic triglycerides and dose-dependent reduction in glycogen stores, as well as increased lipase and NADPH activity, indicating a general disruption to energy metabolism and/or mobilization. Contrary to expectations based on published studies with fish, we found no evidence of lipid peroxidation or induction of the detoxification enzyme Superoxide Dismutase (SOD), however, this may reflect the use of UV treatment as opposed to chlorination for disinfection. Chemical analysis and risk-based prioritization consistently identified fluoxetine, triclosan and diazinon as high-risk contaminants in the wastewater, with nonylphenol and mestranol flagged as risks during one early collection. Research is needed to explore the potential for these specific contaminants to elicit the responses identified in the present study, and to perform similar assessments using wastewater from other locations with different treatment options.

Occurrence and removal of phenolic endocrine disrupting chemicals in the water treatment processes

This paper evaluated the occurrence and removal efficiency of four selected phenolic endocrine disrupting chemicals (bisphenol A (BPA), octylphenol (OP), nonylphenol (NP) and diethylstilbestrol (DES)) in two drinking waterworks in Jiangsu province which take source water from Taihu Lake. The recombined yeast estrogen screen (YES) and liquid chromatography tandem mass spectrometry (LC-MS/MS) were applied to assess the estrogenicity and detect the estrogens in the samples. The estrogen equivalents (EEQs) ranged from nd (not detected) to 2.96 ng/L, and the estrogenic activities decreased along the processes. Among the 32 samples, DES prevailed in all samples, with concentrations ranging 1.46-12.0 ng/L, BPA, OP and NP were partially detected, with concentrations ranging from nd to 17.73 ng/L, nd to 0.49 ng/L and nd to 3.27 ng/L, respectively. DES was found to be the main contributor to the estrogenicity (99.06%), followed by NP (0.62%), OP (0.23%) and BPA (0.09%). From the observation of treatment efficiency, the advanced treatment processes presented much higher removal ratio in reducing DES, the biodegradation played an important role in removing BPA, ozonation and pre-oxidation showed an effective removal on all the four estrogens; while the conventional ones can also reduce all the four estrogens.

Estrogenic activity in Finnish municipal wastewater effluents

Effluents from wastewater treatment plants (WWTPs) are a major source of estrogenic compounds to the aquatic environment. In the present work, estrogenic activities of effluents from eight municipal WWTPs in Finland were studied. The main objectives of the study were to quantify the concentrations of selected estrogenic compounds, to evaluate their contribution to estrogenic potency and to test the feasibility of the commercial bioassays for wastewater analysis. The effluent samples were analyzed by two in vitro tests, i.e. ERα-CALUX(®) and ELISA-E2, and by liquid chromatography mass spectrometry for six estrogenic compounds: estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2), 17α-estradiol and bisphenol A (BPA). Estrogenic effects were found in all of the effluent samples with both of the bioassays. The concentrations measured with ELISA-E2 (8.6-61.6 ng/L) were clearly higher but exhibited a similar pattern than those with chemical analysis (E2 <limit of quantification - 6.8 ng/L) and ERα-CALUX(®) (0.8-29.7 ng E2 EEQ/L). Due to the concentrations under limit of quantification, the evaluation of the chemical contribution to estrogenic potency was possible only for E1 and BPA, which contributed less than 10% to the observed effects, except in one sample with a high BPA contribution (17%). The contribution of E2 was significant in two samples where it was detected (28% and 67%). The results demonstrated that more comprehensive information on potential estrogenic activity of wastewater effluents can be achieved by using in vitro biotests in addition to chemical analysis and their use would be beneficial in monitoring and screening purposes.

Does anti-androgen, flutamide cancel out the in vivo effects of the androgen, dihydrotestosterone on sexual development in juvenile Murray rainbowfish (Melanotaenia fluviatilis)?

The aim of the present study was to investigate if the effects of the androgen, dihydrotestosterone (DHT) on the sexual development in juvenile Murray rainbowfish (Melanotaenia fluviatilis) are canceled out by the anti-androgen, flutamide. Fish (60 days post hatch) were exposed to 250ng/L of DHT, 25μg/L of flutamide (Flu-low), 250μg/L of flutamide (Flu-high), DHT+Flu low and DHT+Flu high. After 35 days of exposure, lengths and weights of the fish were measured and the condition factor (CF) calculated; vitellogenin (VTG) concentrations were measured in tail tissue; sex steroid hormones (17β-estradiol [E2] and 11-keto testosterone [11-KT]) were measured in the head tissue and abdominal regions were used in histological investigation of the gonads. Treatment with DHT reduced the body-length of both male and female fish, an effect which was canceled out by low and high concentrations of flutamide. However, flutamide (low or high) could not nullify the DHT-induced reduction in the CF in either sex. The E2 levels were reduced only in female fish after exposure to DHT but returned to normal after treatment with Flu-high. DHT increased the levels of 11-KT and decreased the E2/11-KT ratio in both sexes. Flu-high, but not Flu-low, could nullify these effects. Both DHT and flutamide (low or high) induced VTG production and this effect persisted when both chemicals were co-administered. Treatment with DHT did not affect gonadal cell development in the testes. However, the female fish treated with DHT contained ovaries in early-vitellogenic stage in comparison to the pre-vitellogenic ovaries in control fish. Co-treatment with flutamide (low or high) resulted in oocyte atresia. The results from the present study suggest that treatment with Flu-high could cancel out DHT-induced effects only on the hormonal profile and body-length in both male and female fish. Juvenile fish co-treated with DHT and flutamide (low or high) had high VTG levels and low CF. In addition, the ovaries in female fish were atretic. These data represent potential adverse effects on the ability of the fish to reproduce successfully.

Removal of micropollutants through a biological wastewater treatment plant in a subtropical climate, Queensland-Australia

BACKGROUND

Municipal wastewaters contain a multitude of organic compounds derived from domestic and industrial sources including active components of pharmaceutical and personal care products and compounds used in agriculture, such as pesticides, or food processing such as artificial sweeteners often referred to as micropollutants. Some of these compounds or their degradation products may have detrimental effects on the environment, wildlife and humans. Acesuflame is one of the most popular artificial sweeteners to date used in foodstuffs. The main objectives of this descriptive study were to evaluate the presence of micropollutants in both the influent and effluent of a large-scale conventional biological wastewater treatment plant (WWTP) in South-East Queensland receiving wastewater from households, hospitals and various industries.

METHODS

Based on USEPA Method 1694: Filtered samples were spiked with mass-labelled chemical standards and then analysed for the micropollutants using liquid chromatography coupled with tandem mass spectrometry.

RESULTS

The presence of thirty-eight compounds were detected in the wastewater influent to the treatment plant while nine of the compounds in the categories of analgesic, anti-inflammatory, alkaloid and lipid/cholesterol lowering drugs were undetectable (100 % removed) in the effluent. They were: Analgesic: Paracetamol, Salicylic acid, Oxycodone; Anti-inflammatory: Naproxen + ve, Atorvastatin, Indomethacin, Naproxen; Alkaloid: Caffeine; Lipid/cholesterol lowering: Gemfibrozol.

CONCLUSIONS

The study results revealed that the micropollutants removal through this biological treatment process was similar to previous research reported from other countries including Europe the Americas and Asia, except for acesulfame, a highly persistent artificial sweetener. Surprisingly, acesulfame was diminished to a much greater extent (>90 %) than previously reported research for this type of WWTPs (45-65 %) that only include physical removal of objects and solids and a biodegradation step.