Removal Of Endocrine Disrupting Compounds Research Articles

Trade-off between Endocrine-Disrupting Compound Removal and Water Permeance of the Polyamide Nanofiltration Membrane: Phenomenon and Molecular Insights.

The polyamide (PA) nanofiltration (NF) membrane has the potential to remove endocrine-disrupting compounds (EDCs) from water and wastewater to prevent risks to both the aquatic ecosystem and human health. However, our understanding of the EDC removal-water permeance trade-off by the PA NF membrane is still limited, although the salt selectivity-water permeance trade-off has been well illustrated. This constrains the precise design of a high-performance membrane for removing EDCs. In this study, we manipulated the PA nanostructures of NF membranes by altering piperazine (PIP) monomer concentrations during the interfacial polymerization (IP) process. The upper bound coefficient for EDC selectivity-water permeance was demonstrated to be more than two magnitudes lower than that for salt selectivity-water permeance. Such variations were derived from the different membrane-solute interactions, in which the water/EDC selectivity was determined by the combined effects of steric exclusion and the hydrophobic interaction, while the electrostatic interaction and steric exclusion played crucial roles in water/salt selectivity. We further highlighted the role of the pore number and residual groups during the transport of EDC molecules across the PA membrane via molecular dynamics (MD) simulations. Fewer pores decreased the transport channels, and the existence of residual groups might cause steric hindrance and dynamic disturbance to EDC transport inside the membrane. This study elucidated the trade-off phenomenon and mechanisms between EDC selectivity and water permeance, providing a theoretical reference for the precise design of PA NF membranes for effective removal of EDCs in water reuse.

Efficient Wastewater Treatment and Removal of Bisphenol A and Diclofenac in Mesocosm Flow Constructed Wetlands Using Granulated Cork as Emerged Substrate

Constructed wetlands (CWs) are considered as low-cost and energy-efficient wastewater treatment systems. Media selection is one of the essential technical keys for their implementation. The purpose of this work was essentially to evaluate the removal efficiency of organic pollution and nitrogen from municipal wastewater (MWW) using different selected media (gravel/gravel amended with granulated cork) in mesocosm horizontal flow constructed wetlands (HFCWs). The results showed that the highest chemical oxygen demand (COD) and ammonium nitrogen removal of 80.53% and 42%, respectively, were recorded in the units filled with gravel amended with cork. The influence of macrophytes (Phragmites australis and Typha angustifolia) was studied and both species showed steeper efficiencies. The system was operated under different hydraulic retention times (HRTs) i.e., 6 h, 24 h, 30 h, and 48 h. The obtained results revealed that the COD removal efficiency was significantly enhanced by up to 38% counter to the ammonium rates when HRT was increased from 6 h to 48 h. Moreover, the removal efficiency of two endocrine-disrupting compounds (EDCs) namely, bisphenol A (BPA) and diclofenac (DCF) was investigated in two selected HFCWs, at 48 h HRT. The achieved results proved the high capacity of cork for BPA and DCF removal with the removal rates of 90.95% and 89.66%, respectively. The results confirmed the role of these engineered systems, especially for EDC removal, which should be further explored.

Enhanced water permeance and EDCs rejection using a UiO-66-NH2-predeposited polyamide membrane

Endocrine disrupting compounds (EDCs) have been increasingly detected in drinking water sources, and pose severe threat to human health. Polyamide (PA) based nanofiltration (NF) membrane has great potential for EDCs removal from water, but the removal of hydrophobic EDCs is not satisfying due to strong hydrophobic affinity. In this study, UiO-66-NH2/PA membranes were prepared by predepositing hydrophilic UiO-66-NH2 onto the substrate prior to interfacial polymerization. The UiO-66-NH2 aggregates increased the permeable area and strengthened the “gutter effect”. Therefore, the pure water flux of UiO-66-NH2/PA increased by 115% compared with that of the thin-film composite (TFC) membrane, and its rejection of Na2SO4 was 96%. The hydrophilicity-enhanced PA film reduced its adsorption of EDCs and decreased the driving force for EDCs diffusion. Moreover, the UiO-66-NH2-induced hydrophilic nanochannels, including the interfacial gaps between PA film and UiO-66-NH2 aggregates, the gaps in UiO-66-NH2 aggregates, and the inherent pores in UiO-66-NH2 crystals, alleviated the hydrophobic affinity and effectively restricted EDCs diffusion. The rejection rates of methylparaben, propylparaben, bisphenol A, and benzylparaben by the optimal UiO-66-NH2/PA were 50%, 67%, 75%, and 85%, respectively, and the water/benzylparaben selectivity was 4.4 times as high as that of TFC. The results demonstrate that incorporating hydrophilic metal-organic frameworks (MOFs) can improve the membrane hydrophilicity and create hydrophilic nanochannels, and is an effective strategy to enhance EDCs removal by nanofiltration.

A comprehensive review on current technologies for removal of endocrine disrupting chemicals from wastewaters

In the recent years, endocrine disrupting compounds (EDCs) has received increasing attention due to their significant toxic effects on human beings and wildlife by affecting their endocrine systems. As an important group of emerging pollutant, EDCs have been detected in various aquatic environments, including surface waters, groundwater, wastewater, runoff, and landfill leachates. Their removal from water resources has also been an emerging concern considering growing population as well as reducing access to fresh water resources. EDC removal from wastewaters is highly dependent on physicochemical properties of the given EDCs present in each wastewater types as well as various aquatic environments. Due to chemical, physical and physicochemical diversities in these parameters, variety of technologies consisting of physical, biological, electrochemical, and chemical processes have been developed for their removal. This review highlights that the effectiveness of EDC removal is highly dependent of selecting the appropriate technology; which decision is made upon a full wastewater chemical characterization. This review aims to provide a comprehensive perspective about all the current technologies used for EDCs removal from various aquatic matrices along with rising challenges such as the antimicrobial resistance gene transfer during EDC treatment.

Removal of pharmaceuticals by advanced treatment methods

The removal of endocrine disrupting compounds (EDCs) remains a big challenge in water treatment in terms of public health. The aim of the study was evaluating the performance of nano TiO2, ozone, and UV system for removal of EDCs. In this study, the efficiency of the nano TiO2 to degrade target EDCs under catalytic and photocatalytic ozonation was examined at different operational conditions. The maximum removal of target pollutant was obtained with pH 6.8; ozone concentration 10 mg/L; catalyst dosage 0.050 g/L and the duration time of the photocatalytic performances was 10 min showing the most treatment conditions respectively. In addition, the surface reaction mechanism of endocrine disrupting compound removal by catalytic and photocatalytic ozonation was investigated. The results showed that the catalyst can significantly enhance the removal of target compound. The 99.0%, 88.3% and 51.8% removal rates were obtained at photocatalytic ozonation, catalytic ozonation and sole ozonation, respectively. These results indicated that the Ozone/TiO2/UV process was favorable for engineering applications for removal of endocrine disrupting compounds such as steroid hormone and likely similar micro pollutants.

Contemporary Techniques for Remediating Endocrine-Disrupting Compounds in Various Water Sources: Advances in Treatment Methods and Their Limitations.

Over the years, the persistent occurrence of superfluous endocrine-disrupting compounds (EDCs) (sub µg L−1) in water has led to serious health disorders in human and aquatic lives, as well as undermined the water quality. At present, there are no generally accepted regulatory discharge limits for the EDCs to avert their possible negative impacts. Moreover, the conventional treatment processes have reportedly failed to remove the persistent EDC pollutants, and this has led researchers to develop alternative treatment methods. Comprehensive information on the recent advances in the existing novel treatment processes and their peculiar limitations is still lacking. In this regard, the various treatment methods for the removal of EDCs are critically studied and reported in this paper. Initially, the occurrences of the EDCs and their attributed effects on humans, aquatic life, and wildlife are systematically reviewed, as well as the applied treatments. The most noticeable advances in the treatment methods include adsorption, catalytic degradation, ozonation, membrane separation, and advanced oxidation processes (AOP), as well as hybrid processes. The recent advances in the treatment technologies available for the elimination of EDCs from various water resources alongside with their associated drawbacks are discussed critically. Besides, the application of hybrid adsorption–membrane treatment using several novel nano-precursors is carefully reviewed. The operating factors influencing the EDCs’ remediations via adsorption is also briefly examined. Interestingly, research findings have indicated that some of the contemporary techniques could achieve more than 99% EDCs removal.

Current advances in treatment technologies for removal of emerging contaminants from water – A critical review

• Brief summary of the existing knowledge regarding ECs. • Application and operational perspectives of classical and advanced treatment technologies. • The appropriateness of advanced integrated technologies for ECs removal. • Mechanisms involved in ECs removal processes. • Identification of the gap areas for future research and developments. The presence and persistence of emerging contaminants (ECs) such as endocrine disrupting compounds (EDCs), personal care products (PCPs), pharmaceuticals and their transformed products are the matter of serious environmental and health concerns. This review details the sources, classification, fate and transport of ECs, and the classical, advanced, and integrated treatment technologies for their removal. Up to 100% of β-blockers, pharmaceuticals, EDCs, and pesticides can be removed via advanced oxidation process. The microalgae/fungal strains and the anaerobic membrane bioreactors are also promising processes for PPCPs and EDCs removal. RO and NF membranes exhibited excellent removal efficiencies for range of ECs, however, these processes are conditioned with fouling issues. The combination of membrane separation and electrochemical oxidation is appeared efficacious to lessen the major confines of both technologies such as fouling in membrane process and the mass transfer constraint in the electrochemical oxidation process. The effect of operational parameters on the process efficiency, and the mechanisms involved in different processes were discussed. This review will help in selecting the best available technology (BAT) for specific contaminant under particular conditions. Capsule. This review details the sources, classification, fate and transport of emerging contaminants and the recent researches and advancements for their treatment/elimination.

Enhanced removal of hydrophobic endocrine disrupting compounds from wastewater by nanofiltration membranes intercalated with hydrophilic MoS2 nanosheets: Role of surface properties and internal nanochannels

The presence of endocrine disrupting compounds (EDCs) in water and wastewater poses potential risks on aquatic environment and human health. Conventional polyamide (PA) nanofiltration (NF) membrane showed poor rejection against EDCs due to unfavorable hydrophobic interaction. In this study, we introduced MoS2 nanosheets (NS) to PA NF membrane by pre-deposition before the interfacial polymerization process, creating hydrophilic surface and nanochannels in the PA rejection layer to enhance removal of hydrophobic EDCs from wastewater. Results showed that the MoS2 NS intercalated membrane simultaneously enhanced water permeance and EDCs rejection, with water/EDC selectivity nearly 6 times larger compared to the control. The enhanced EDC rejection was primarily attributed to the suppressed hydrophobic interaction between membrane surface and hydrophobic EDCs, as well as the selective effect by the MoS2 NS-induced nanochannels. Further calculation based on the solution-diffusion theory indicated that for MoS2 NS intercalated membranes the selective nanochannels played a more important role than the hydrophilic surface in impeding the transport of EDCs across the PA layer. The feasibility of the MoS2 NS intercalated PA membrane for EDC removal was also verified using EDC-contaminated real wastewater. The results of this work highlight the potential of using the designed NF membranes for efficient removal of targeted organic micropollutants from water and wastewater.

Endocrine Disrupting Compounds Removal Methods from Wastewater in the United Kingdom: A Review

Endocrine disrupting compounds (EDCs) are contaminants with estrogenic or androgenic activity that negatively impact human and animal communities. These compounds have become one of the most significant concerns for wastewater treatment in recent decades. Several studies have evaluated EDC removal methods from wastewater across the globe, including the United Kingdom (UK). Accordingly, the current study reviews EDC removal methods from municipal/domestic wastewater in the United Kingdom (UK) for the period of 2010–2017. The current study analysed original research articles (250), review articles (52), short communication (43), and other associated documents via the ScienceDirect.com database. A total of 25 published articles, which covered EDC removal methods from UK wastewaters, were reviewed rigorously. The research highlights that despite the relative efficacy of existing chemical and physical methods for removing certain EDCs from wastewater, there is emerging evidence supporting the need for more widespread application of nature-based and biological approaches, particularly the use of biofilms. The analysis reveals that there have been relatively few research studies on EDC removal methods carried out in the UK in the 2010–2017 period. Only four papers addressed the removal of specific endocrine disrupting compounds from UK municipal wastewater, and none of the studies addressed EDC removal by using direct biofilms. Finally, this review suggests that more research is needed to remove EDCs, particularly through the application of biofilms, from municipal wastewater in current scenarios.

Enhanced removal of phenolic endocrine disrupting chemicals from coastal waters by intertidal macroalgae

The phytoremediation of phenolic endocrine disrupting compounds (EDCs) in coastal waters by intertidal macroalgae was firstly investigated. The results showed that intertidal macroalgae could remove bisphenol A (BPA) and nonylphenol (NP) at environmental relevant concentration, and Ulva pertusa was the most efficient one. In most cases, the order of EDCs removal efficiency could be expressed as: green algae > brown algae > red algae. The in-situ monitoring using a charge‐coupled device imaging system confirmed the accumulation of EDCs in the intertidal macroalgae. The removal mechanisms included the initial rapid biosorption process, followed by the slow accumulation and biodegradation. The removal efficiency of BPA and NP was slightly dependent on temperature and nutrient concentration. A linear relationship was observed between the initial concentration and the average removal rate (R2 > 0.99). The BPA and NP at the environmental relevant concentration (100 μg L−1) could be removed efficiently using Ulva pertusa even after three cycles in pilot-scale experiments. The high removal efficiency of NP and BPA was also confirmed by the field investigation from the intertidal zone with abundant Ulva pertusa. These findings demonstrated that intertidal macroalgae could play essential role for the phytoremediation of phenolic EDCs in coastal waters.

Theoretical Study of Ozonation of Methylparaben and Ethylparaben in Aqueous Solution.

Parabens are widely employed in toothpaste, cosmetics, textiles, beverages, and preservatives, causing a serious environmental concern because they are endocrine-disrupting compounds (EDCs). As one of the highly reactive oxidants, ozone has a great effect on EDC removal. To understand the degradation and transformation of parabens in the aquatic environment and their toxicity to aquatic organisms, the degradation reaction of parabens initiated by O3 was studied meticulously using quantum chemical calculations. The degradation process includes multiple initial reaction channels and consequent degradation pathways of the Criegee intermediates. Through thermodynamic data, the rate constants were computed using the transition state theory (TST). At a temperature of 298 K and a pressure of 1 atm, the calculated rate constants were 3.92 and 3.94 M-1 s-1 for methylparaben (MPB) and ethylparaben (EPB), respectively. The rate constants increased as the temperature increased or as the length of the alkyl chain on the benzene ring increased. Through the ecotoxicity assessment procedure, the ecotoxicity of parabens and the products in the degradation process can be assessed. Most degradation byproducts are either less toxic or nontoxic. Some byproducts are still harmful, such as oxalaldehyde (P2) and ethyl 2,3-dioxopropanoate (P10). Furthermore, the ecological toxicity of parabens increased with augmentation of the alkyl chain on the benzene ring. The effect of the alkyl chain length on the benzene ring in the compound cannot be ignored.

Adsorption of endocrine disrupting compounds from aqueous solution in poly(butyleneadipate-co-terephthalate) electrospun microfibers

Endocrine disrupting compounds (EDC) have the potential to seriously impact ecosystems and humans. To date, numerous techniques have been investigated for removing such contaminants from water, including biodegradation, photocatalysis, ozonation, and the Fenton process. However, these methods are expensive from the perspectives of equipment and operating costs. Herein, we investigated the use of electrospun poly(butyleneadipate-co-terephthalate) (PBAT) fibers as an adsorbent material for the removal of EDC for the first time. The morphological characteristics of the electrospun microfibers were assessed by scanning electron microcopy, atomic force microscopy, specific surface area analysis, and dynamic mechanical analysis. In addition, their physicochemical characteristics were evaluated using thermal gravimetry, attenuated total reflection–Fourier-transform infrared spectroscopy, and hydrophobicity testing. Adsorption experiments were carried out using various concentrations of estrone (E1), 17β-estradiol (E2), and 17α-ethynylestradiol (EE2). The adsorption kinetics and isotherms revealed that the maximum adsorption capacities of PBAT microfibers towards the three contaminants follow the order: EE2 (2.23 mg g−1) > E1 (1.41 mg g-1) > E2 (0.796 mg g−1). We assume that hydrophobic and π–π interactions play important roles in the adsorption mechanism. In addition, we demonstrated that PBAT microfibers are potentially very reusable and can be recycled at least five times without the loss of adsorption capacity. We conclude that electrospun PBAT microfibers exhibit excellent properties and have the potential to be used as an adsorbent material for the removal of EDC from aqueous solutions.

Studies on the Removal of Endocrine-Disrupting Compounds From Aqueous Streams by Emulsion Liquid Membrane and Hollow Fiber Supported Liquid Membrane

Endocrine disrupting compounds (EDC) possess xenobiotic and exogenous roots which limits the natural functioning of the endocrine system like synthesis, secretion, transference and binding in animals and human being. Humans, animals and industries discharges EDC to soil, surface/ground water and sediments mostly through sewage treatment system. Studies have shown the impact of EDC on nervous system, lungs, liver, thyroid, prostate, reproductive system, metabolism, obesity etc. So removal of these compounds by suitable processes is necessary. Conventional techniques like coagulation, precipitation, flocculation, microfiltration, ultrafiltration etc. are not are not that much effective for the removal of EDC having low molecular weight and are also limited by the pore sizes. The current study emphases on the use of techniques like Emulsion liquid membrane and Hollow fiber supported liquid membrane which are the promising techniques for the removal of EDC from aqueous streams. The working and implementation of these two techniques in the removal of several EDC from aqueous streams are also discussed.

The use of peracetic acid for estrogen removal from urban wastewaters: E2 as a case study.

17β-Estradiol (E2) is a natural estrogen produced by the feminine endocrine system. It is excreted mainly through urine and feces. Exposure to E2 may affect the reproductive system of both animals and humans, especially since the removal of E2 in conventional processes and technologies present in the wastewater treatment plants is not sufficient. Chlorine is one of the most studied and used oxidant worldwide. Although there are studies that demonstrate the endocrine disrupting compounds removal like E2, its reaction with organic matter can originate by-products, namely, trihalomethanes, which are known to have high toxic potential. The main aim of the present study was to evaluate the removal of E2 (50μgE2L-1-maximum concentration) using peracetic acid (PAA), a seeming cleaner and innocuous alternative to chlorine. To this end, a series of jar tests were performed, using different peracetic acid concentrations (1, 5, 10, and 15mgL-1) and contact times (10, 15, and 20min). The results obtained showed that a peracetic acid concentration of 15mgL-1 with a contact time of 20min had a removal efficacy of approximately 100%. The second main goal of this study was to evaluate the ecotoxicological potential of the tested treatments on the zebrafish Danio rerio. Several oxidative stress biomarkers were evaluated, namely glutathione S-transferase, lipid peroxidation, and catalase, besides vitellogenin. Both peracetic acid and E2 caused significant increases in the oxidative stress biomarkers, although this did not lead to increased lipid peroxidation levels. In addition, peracetic acid significantly decreased the estrogenic activity of E2, as indicated by decreased vitellogenin levels. Peracetic acid demonstrated to have great potential as an alternative disinfectant for chlorine treatments, and indications for future research are discussed.

Hydrophilic Selective Nanochannels Created by Metal Organic Frameworks in Nanofiltration Membranes Enhance Rejection of Hydrophobic Endocrine-Disrupting Compounds.

Rejection of endocrine-disrupting compounds (EDCs) by thin-film composite (TFC) polyamide membranes remains a challenging issue in wastewater reclamation applications because of the unfavorable hydrophobic interaction between EDCs and membranes. Herein, we investigated the incorporation of hydrophilic metal organic frameworks (MOFs) into the polyamide layer to create water/EDC selective nanochannels for enhancing EDC rejection. Using MIL-101(Cr) MOF as a nanofiller, the water flux of the MOF0.20 TFC membrane (0.20 wt/v % MOF in n-hexane) was 2.3 times that of the control. The rejection rates against EDCs involving methylparaben, propylparaben, benzylparaben, and bisphenol A (BPA) by MOF0.20 were also significantly higher than the respective values of the control membrane, with the water/EDC selectivity (e.g., A/BBPA) of MOF0.20 approximately doubled compared to that of the control. Further single salt rejection and gold nanoparticle filtration tests confirmed that the hydrophilic nanochannels created by MOFs played a critical role in membrane transport, accounting for the significant enhancement of EDC rejection of the modified TFC membrane. This study demonstrates a promising membrane modification protocol using hydrophilic MOFs for achieving selective removal of EDCs and high-efficient wastewater reclamation using TFC membranes.

Removal of selected endocrine-disrupting compounds using Al-based metal organic framework: Performance and mechanism of competitive adsorption

Endocrine disrupting compounds (EDCs) present serious environmental problems due to their negative impacts on lifeforms. To solve these issues, a metal–organic frameworks (MOF) was used as an efficient adsorbent for the removal of EDCs. This work was mainly conducted to (i) characterize the adsorbent, (ii) establish the feasibility of MOF for removal of the selected EDCs (bisphenol A (BPA), 17α-ethynylestradiol (EE2), and perfluorooctanoic acid (PFOA)), and (iii) study the competitive adsorption mechanism. Physicochemical properties of MOF were characterized by microscopy, porosimetry, and zeta potential analyses. Feasibility testing of MOF was conducted under various solution conditions to determine the effect of solution temperature, pH, background ions, and humic acid on the adsorption capacity. The adsorption process in this study was spontaneous reaction, considering the negative value of ΔG0 derived from experiments of solution temperature. According to experimental results related to the adsorbent dose, the maximum equilibrium adsorption capacity (qe) for BPA, EE2, and PFOA by MOF was 138.4, 200.4, and 169.2mgg−1, respectively. The adsorption mechanism of the EDCs was clearly explained by numerous solution factors (i.e., pH, background ions, and the existence of humic acid), and synergetic effects of hydrophobic and electrostatic interactions were important to explain the adsorption mechanism.

Application of carbon nanotubes for removal of emerging contaminants of concern in engineered water and wastewater treatment systems

Pharmaceuticals and personal care products (PPCPs) and endocrine disrupting compounds (EDCs) have been detected in wastewater effluents and surface water bodies at concentrations ranging from parts per trillion levels (ng L−1) to parts per billion (µg L−1) levels. Currently, engineered wastewater treatment plants are unable to remove PPCPs and EDCs completely, resulting in the treatment plants becoming a source of secondary pollution. Research on carbon nanotubes (CNTs) has shown that the tubular cylinders of carbon atoms due to their large specific surface area and developed pore structure are capable of adsorbing and remediating PPCPs and EDCs. They also possess excellent photocatalytic activity and high mechanical strength. When combined with membrane filtration, CNTs demonstrate excellent removal of PPCPs and EDCs with removal up to ~ 95% in optimum experimental conditions. Nanocomposite membranes containing CNTs have shown promising results in the removal of triclosan, acetaminophen, and ibuprofen. In addition to its proven potential in adsorption and membrane filtration, CNTs can also be used in photocatalytic degradation of a variety of organic compounds including PPCPs and EDCs. When CNT is used as a photocatalyst, it generates reactive oxygen species that can oxidize contaminants to CO2, and H2O. This study provides a comprehensive literature review of the application of CNTs for removal of the emerging contaminant of concern from water and wastewater. Their application, particularly in the areas of adsorption, filtration and photocatalytic degradation of PPCPs and EDCs, is discussed in detail. Also, the feasibility of a full-scale implementation of CNTs in existing water and wastewater treatment plants is discussed.

Endocrine Disrupting Compounds Removal Methods from Wastewater in the United Kingdom: A Review

Endocrine disrupting compounds (EDCs) are contaminants with estrogenic or androgenic activity that negatively impact human and animal communities. These compounds have become one of the significant concerns for wastewater treatment in recent decades. Several studies have evaluated EDC removal methods from wastewater across the globe including the United Kingdom (UK). Accordingly, the current study reviews EDC removal methods from municipal/domestic wastewater in the United Kingdom (UK) for the period of 2010–2017. The research highlights that despite the relative efficacy of existing chemical and physical methods for removing certain EDCs from wastewater there is emerging evidence supporting the need for more widespread application of nature-based and biological approaches, particularly the use of biofilms. The analysis reveals that there have been relatively few research studies on EDC removal methods have been carried out in the UK in the 2010–2017 period and none of the research focused on EDC removal using biofilms. Finally, this review suggests that more research is needed to remove EDCs, particularly through the application of biofilms, from municipal wastewater in current scenarios.

Comparative assessment of endocrine disrupting compounds removal in heterotrophic and enriched nitrifying biomass

Despite the number of studies that have investigated the fate of endocrine disrupting compounds (EDCs), to date results are still contradictory and more research is required to evaluate the contribution of the microbial communities present in different engineered treatment systems. Thus, autotrophic and heterotrophic types of biomass were here compared in terms of efficiency in the removal of estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethynilestradiol (EE2) and bisphenol A (BPA). Experiments were performed with enriched nitrifying activated sludge (NAS) and enriched ammonia oxidizing bacteria (AOB) sludge cultivated at lab-scale, as well as with conventional activated sludge (CAS) from a full-scale wastewater treatment plant. Both enriched NAS and AOB demonstrated a negligible degrading capacity. In both cases, the studied EDCs exhibited low removals (<14%) and showed no correlation with the increasing nitrification rates contradicting some of the hypothesis present in literature. Contrariwise, the biodegradation capabilities of the heterotrophic fraction of CAS were highlighted. E2 and E3 were removed by up to 100% and 78%, respectively. E1 was found to be the main transformation product of E2 (almost quantitative oxidation) and it was also highly eliminated. Finally, EE2 and BPA were more persistent biologically with removals ranging from 10% to 39%. For these two compounds similar removals were obtained during experiments with heat-inactivated biomass suggesting that sorption could be a relevant route of elimination.

Endocrine disrupting compounds in streams in Israel and the Palestinian West Bank: Implications for transboundary basin management

Endocrine disrupting compounds (EDCs) frequently enter surface waters via discharges from wastewater treatment plants (WWTPs), as well as from industrial and agricultural activities, creating environmental and health concerns. In this study, selected EDCs were measured in water and sediments along two transboundary streams flowing from the Palestinian Authority (PA) into Israel (the Zomar-Alexander and Hebron-Beer Sheva Streams). We assessed how the complicated conflict situation between Israel and the PA and the absence of a coordinated strategy and joint stream management commission influence effective EDC control. Both streams receive raw Palestinian wastewater in their headwaters, which flows through rural areas and is treated via sediment settling facilities after crossing the 1949 Armistice Agreement Line. Four sampling campaigns were conducted over two years, with concentrations of selected EDCs measured in both the water and the sediments. Results show asymmetrical pollution profiles due to socio-economic differences and contrasting treatment capacities. No in-stream attenuation was observed along the stream and in the sediments within the Palestinian region. After sediment settling in treatment facilities at the Israeli border, however, significant reductions in the EDC concentrations were measured both in the sediments and in the water. Differences in sedimentation technologies had a substantial effect on EDC removal at the treatment location, positively affecting the streams' ability to further remove EDCs downstream. The prevailing approach to addressing the Israeli-Palestinian transboundary wastewater contamination reveals a narrow perspective among water managers who on occasion only take local interests into consideration, with interventions focused solely on improving stream water quality in isolated segments. Application of the “proximity principle” through the establishment of WWTPs at contamination sources constitutes a preferable strategy for reducing contamination by EDCs and other pollutants to ensure minimization of public health risks due to the pollution of streams and underlying potable groundwater.