Occurrence and removal of bisphenol analogues in wastewater treatment plants and activated sludge bioreactor

Hydrogel immobilized bacteria@metal-organic-frameworks composite augmented bisphenol A removal from activated sludge and its regulation behavior on sludge community

Improving degradation efficiency of activated sludge towards bisphenol A (BPA) is related to water safety. A hydrogel immobilized bacteria@metal-organic-frameworks (im-SQ-2@MOFs) was synthesized previously, which was a composite formed by metal organic frameworks adhering to BPA degrading bacteria. Accordingly, this study added im-SQ-2@MOFs as enhancer to augment the BPA degradation ability of activated sludge. Results indicated that after the addition of im-SQ-2@MOFs, the augmented activated sludge system maintained 90 % BPA degradation rate for 10 mg/L BPA. Meanwhile, the system also presented 80-97 % degradation effect for other phenolic pollutants. Augmentation mechanism was revealed through multi-omics analysis. Firstly, im-SQ-2@MOFs enriched the degradation functional microorganisms in activated sludge, and microbial communication was further prompted. Besides, organic compounds degrading enzymes were upregulated to intensify BPA hydrolysis. Furthermore, electron transfer during BPA degradation was accelerated. Results provide new perspective on the development of bio-augmented materials to improve the efficiency of sewage treatment plants. TAKE HOME MESSAGE.

Simultaneous targeted and non-targeted analysis of contaminants in fertilizers in Quebec, Canada

In this study, an LC-MS based analytical method was developed and validated for the simultaneous targeted analysis (14 bisphenols and 14 plasticizers) and suspect screening of other plastic-related contaminants in various types of fertilizers. The ultrasound-assisted extraction method showed overall satisfactory performances, achieving a median absolute recovery of 85 % for the target compounds in different types of fertilizers. The method was applied to sixteen different types of fertilizers, including fertilizing residual materials (n = 8 types), one cattle manure, and seven mineral fertilizers collected in Quebec, Canada in 2022 and 2023. Relatively higher levels of the targeted bisphenols and plasticizers were detected in some fertilizing residual materials, such as municipal biosolids and deinking residues. 4-Hydroxyphenyl 4-isoprooxyphenylsulfone (D-8) and bis(2-ethylhexyl) phthalate (DEHP) were dominant contaminants in these matrixes, with concentrations up to 35.6 and 64.7 μg g-1 dw, respectively. A non-targeted workflow was successfully applied to municipal biosolids and deinking residues, and >30 contaminants were identified across multiple chemical families at level 1 identification confidence, with most of them previously unreported in various types of fertilizers. For example, new color developers, N-(2-((Phenylcarbamoyl)amino)phenyl)benzenesulfonamide (NKK-1304) and 2,4-bis(phenylsulfonyl)phenol (DBSP), were reported in deinking residues. This work illustrates the complexity of the contaminant mixtures in fertilizers such as municipal biosolids and deinking residues.

Innovative approaches to electrochemical oxidation of Bisphenol B in synthetic and complex water environments

The substitution of Bisphenol A (BPA) with Bisphenol B (BPB) has raised concerns due to BPB's increased environmental presence and its potential hazards. Despite the frequent detection in water environments, effective removal methods for BPB are still limited. This study hypothesizes that electrochemical oxidation (EO) can effectively degrade BPB and its by-products. To test this, EO was applied under various conditions, analyzing the role of anode material, current density, pH, and BPB concentration. The results revealed that BPB degradation followed pseudo-first-order kinetics, with boron-doped diamond (BDD) anode showing a rate constant 27 times higher than iridium oxide electrodes. After 180 min, BDD achieved 81.8 % mineralization of BPB. The remaining organic load was associated to easily biodegradable short-chain carboxylic acids. Additionally, the EO process was evaluated in different matrices, including drinking water, tap water, simulated municipal wastewater, and synthetic urine, to assess the impact of matrix complexity. Electrogenerated oxidants, such as hydroxyl radicals, sulfate radicals, and active chlorine, significantly enhanced BPB degradation rates in real water matrices. Energy consumption varied from 5.32 kWh m-3 in drinking water to 2.28 kWh m-3 in synthetic urine, demonstrating the role of matrix composition in EO efficiency. These findings show that EO is a promising technology for removing BPB and similar chemicals in real-world water matrices.

Unveiling bisphenol A toxicity: human health impacts and sustainable treatment strategies

INTRODUCTION

The widespread presence of bisphenol-A (BPA) in consumer goods like water bottles and eyeglass frames raises serious concerns about the chemical's ability to accumulate in human tissues. Molecular filtration and activated carbon adsorption are two of the many BPA treatment technologies that have emerged in response to these issues; both are essential in the removal or degradation of BPA from water sources and industrial effluents.

CONTENT

To secure the long-term health and environmental advantages of BPA treatment approaches, sustainable development is essential. Both the efficient elimination or destruction of BPA and the reduction of the treatment operations' impact on the environment are important components of a sustainable approach. Different search engines like Pub-Med, MEDLINE, Google Scholar and Scopus are used for these systematic reviews and analyzed accordingly. This can be accomplished by making treatment facilities more energy efficient and using environmentally friendly materials. Greener ways to deal with BPA pollution are on the horizon, thanks to innovative techniques like bioremediation and improved oxidation processes. Reducing dependence on conventional, resource-intensive procedures can be achieved by investigating the use of bio-based materials and natural adsorbents in treatment processes.

SUMMARY AND OUTLOOK

This review article tackling the health and environmental concerns raised by BPA calls for an integrated strategy that incorporates sustainable development principles and technology progress. We can reduce the negative impacts of BPA contamination, improve environmental stewardship in the long run, and ensure human health by combining cutting-edge treatment technologies with sustainable behaviours.

Adverse outcomes of the newly emerging bisphenol A substitutes

BPA and its analogues are facing increasingly stringent regulations restricting their use due to the increasing knowledge of their harmful effects. It is therefore expected that novel BPA analogues and alternatives will replace them in plastic products, cans and thermal paper to circumvent restrictions imposed by legislation. This raises concerns about the safety of "BPA-free" products, as they contain BPA substitutes whose safety has not been sufficiently assessed prior to their market introduction. The regulatory agencies have recognised BPAP, BPBP, BPC2, BPE, BPFL, BPG, BPP, BPPH, BPS-MAE, BPS-MPE, BP-TMC, BPZ and the alternatives BTUM, D-90, UU and PF201 as compound with insufficient data regarding their safety. We demonstrate that the mentioned compounds are present in consumer products, food and the environment, thus exhibiting toxicological risk not only to humans, but also to other species where their toxic effects have already been described. Results of in silico, in vitro and in vivo studies examining the endocrine disruption and other effects of BPA analogues show that they disrupt the endocrine system by targeting various nuclear receptors, impairing reproductive function and causing toxic effects such as hepatotoxicity, altered behaviour and impaired reproductive function. In vitro and in vivo data on BPA alternatives are literally non-existent, although these compounds are already present in commonly used thermal papers. However, in silico studies predicted that they might cause adverse effects as well. The aim of this article is to comprehensively collate the information on selected BPA substitutes to illustrate their potential toxicity and identify safety gaps.

Temperature-dependent microbial mechanism and accumulation of volatile fatty acids in primary sludge pretreated with peroxymonosulfate

For revealing the influence of temperature on volatile fatty acids (VFAs) generation from primary sludge (PS) during the anaerobic fermentation process facilitated by peroxymonosulfate (PMS), five fermentation groups (15, 25, 35, 45, and 55 °C) were designed. The results indicated that the production of VFAs (5148 mg COD/L) and acetic acid (2019 mg COD/L) reached their peaks at 45 °C. High-throughput sequencing technology disclosed that Firmicutes, Proteobacteria, and Actinobacteria was the dominant phyla, carbohydrate metabolism and membrane transport were the most vigorous at 45 °C. Additionally, higher temperature and PMS exhibit synergistic effects in promoting VFAs accumulation. This study unveiled the mechanism of the effect of the pretreatment of PS with PMS on the VFAs production, which established a theoretical foundation for the production of VFAs.

Feasibility of sulfated BPA and BPS as wastewater-based epidemiology biomarkers: Insights from wastewater and reported human urine analysis

In wastewater-based epidemiology (WBE), the selection of appropriate biomarkers presents a significant challenge. Recently, sulfated bisphenols have garnered attention as potential WBE biomarkers due to their increased stability in wastewater compared to glucuronide conjugates. This study aims to comprehensively assess the feasibility of employing sulfated BPA and BPS as WBE biomarkers by analyzing both WBE and human biomonitoring data. To conduct this research, wastewater samples were collected from six domestic wastewater treatment plants in Guangzhou, China, and urinary concentration of BPA and BPS were obtained from peer-reviewed literature. The results revealed that mean urinary concentrations of BPA and BPS, calculated using Monte Carlo simulations, significantly exceeded those reported in human biomonitoring studies. Furthermore, the per capita mass load ratio of sulfated BPA and BPS in human urine to the mass load in wastewater was found to be below 10 %. This outcome suggests that the excretion of BPA-S and BPS-S in urine does not make a substantial contribution to wastewater, hinting at the existence of other notable sources. Consequently, our study concludes that sulfated BPA-S and BPS-S are not suitable candidates as WBE biomarkers. This work provides a referenceable analytical framework for evaluating the feasibility of WBE biomarkers and emphasizes the necessity for caution when utilizing WBE to assess human exposure to chemicals.

Application of calcium peroxide in promoting resource recovery from municipal sludge: A review

The harmless disposal, resource recovery, and synergistic efficiency reduction of municipal sludge have been the research focuses for the last few years. Calcium peroxide (CaO2) is a multifunctional and safe peroxide that produces an alkaline oxidation environment to promote the fermentation of municipal sludge to produce hydrogen (H2) and volatile fatty acids (VFAs), thus realizing sludge resource recovery. This review outlines the research achievements of CaO2 in sludge resource recovery, improvement of sludge dewaterability, and removal of pollutants from sludge in recent years. Meanwhile, the mechanism of CaO2 and its influencing factors have also been comprehensively summarized. Finally, the future development direction of the application of CaO2 in municipal sludge is prospected. This review would provide theoretical reference for the potential engineering applications of CaO2 in improving sludge treatment in the future.

Bisphenol A affects microbial interactions and metabolic responses in sludge anaerobic digestion

The widespread use of bisphenol A (BPA) has resulted in the emergence of new pollutants in various environments, particularly concentrated in sewage sludge. This study investigated the effects of BPA on sludge anaerobic digestion, focusing specifically on the interaction of microbial communities and their metabolic responses. While the influence of BPA on methane accumulation is not significant, BPA still enhanced the conversion of soluble COD, protein, and polysaccharides. BPA also positively influenced the hydrolysis-acidogenesis process, leading to 17% higher concentrations of volatile fatty acids (VFAs). Lower BPA levels (0.2-0.5 mg/kg dw) led to decreased hydrolysis and acidogenesis gene abundance, indicating metabolic inhibition; conversely, higher concentrations (1-5 mg/kg dw) increased gene abundance, signifying metabolic enhancement. Diverse methane metabolism was observed and exhibited alterations under BPA exposure. The presence of BPA impacted both the diversity and composition of microbial populations. Bacteroidetes, Proteobacteria, Firmicutes, and Chloroflexi dominated in BPA-treated groups and varied in abundance among different treatments. Changes of specific genera Sedimentibacter, Fervikobacterium, Blvii28, and Coprothermobacter in response to BPA, affecting hydrolysis and acetogenesis. Archaeal diversity declined while the hydrogenotrophic methanogen Methanospirillum thrived under BPA exposure. BPA exposure enabled microorganisms to form structured community interaction networks and boost their metabolic activities during anaerobic digestion. The study also observed the enrichment of BPA biodegradation pathways at high BPA concentrations, which could interact and overlap to ensure efficient BPA degradation. The study provides insights into the digestion performance and interactions of microbial communities to BPA stress and sheds light on the potential effect of BPA during anaerobic digestion.

The environmental occurrence, fate, and risks of 25 endocrine disruptors in Slovenian waters

Natural hormones, synthetic steroids and bisphenols are among the most active endocrine disruptors (EDs) in the aquatic environment, with great potential for causing adverse effects in aquatic organisms and humans. In this study, a focused group of 25 potent estrogenic and other ED compounds were simultaneously measured in wastewaters (WWs) and receiving surface waters (SWs) before and after wastewater treatment plants (WWTPs), where their removal efficiency was also estimated. Up to 16 of 25 EDs were successfully quantified in SWs and WWs, with bisphenols BPS, BPA, and BPF together with estriol and chlormadinone being the most prevalent with the highest measured concentrations of up to 35 μg/L in WWs and 400 ng/L in SWs. High load and insufficient removal of these substances by WWTPs lead to a significant increase in their concentrations in the receiving SWs downstream, while other sources could be responsible for an important portion of river contamination with EDs. Removal efficiency was very good for most EDs, although only from 0 to 44 % for E2, which shows a need for the improvement of current removal techniques. E2 and EE2 contribute the most to the alarmingly high risks of the total ED estrogenic potential, with the value increased by 36 % in SWs downstream from WWTPs, and the RQ value for the total estrogenic potential in individual SW samples being three orders of magnitude higher than that representing high risk. An additional comprehensive multi-parameter risk assessment determined high risk quotient and priority index values for BPA, E2, BPS and E1 with values of up to 450 in SWs. Our results show a focused insight into the risks associated with an important group of EDs and the role of WWTPs, while further highlighting the importance of regular monitoring of the environmental occurrence and risks of a focused range of EDs.

Maximizing diesel removal from contaminated sand using Scirpus mucronatus and assessment of rhizobacteria addition effect

Phytoremediation is one of the green technologies that is friendly to nature, utilizes fewer chemicals, and exhibits good performance. In this study, phytoremediation was used to treat diesel-contaminated sand using a local aquatic plant species, Scirpus mucronatus, by analyzing the amount of total petroleum hydrocarbons (TPHs). Optimization of diesel removal was performed according to Response Surface Methodology (RSM) using Box-Behnken Design (BBD) under pilot-scale conditions. The quadratic model showed the best fit to describe the obtained data. Actual vs. predicted values from BBD showed a total of 9.1 % error for the concentration of TPH in sand and 0 % error for the concentration of TPH in plants. Maximum TPH removal of 42.3 ± 2.1 % was obtained under optimized conditions at a diesel initial concentration of 50 mg/kg, an aeration rate of 0.48 L/min, and a retention time of 72 days. The addition of two species of rhizobacteria (Bacillus subtilis and Bacillus licheniformis) at optimum conditions increased the TPH removal to 51.9 ± 2.6 %. The obtained model and optimum condition can be adopted to treat diesel-contaminated sand within the same TPH range (50-3000 mg/kg) in sand.

Transport of bisphenol A, bisphenol S, and three bisphenol F isomers in saturated soils

With the limitation of the use of bisphenol A (BPA), the production of its substitutes, bisphenol S (BPS), and bisphenol F (4,4'-BPF) is increasing. Understanding the fate and transport of BPA and its substitutes in porous media can help reduce their risk of contaminating soil and groundwater systems. In this study, column and batch adsorption experiments were performed with 14C-labeled bisphenol analogs and combined with mathematical models to investigate the interaction of BPA, BPS, 4,4'-BPF, 2,2'-BPF, and 2,4'-BPF with four standard soils with different soil organic matter (SOM) contents. The results show that the transport capacity of BPS and 4,4'-BPF in the saturated soils is significantly stronger than that of BPA. Meanwhile, the mobility of the three isomers of bisphenol F exhibits variability in saturated soils with high SOM content. The two-site nonequilibrium sorption model was applied to simulate and interpret column experimental data, and model simulations described the interactions between the bisphenol analogs and soil very well. The fitting results underscore SOM's role in providing dynamic adsorption sites for bisphenol analogs. Hydrophobicity primarily accounts for the disparity in adsorption affinity between BPA, BPS, 4,4'-BPF, and soil, whereas hydrogen bonding forces may predominantly influence the differential adsorption affinity between 4,4'-BPF and its isomers and soil. The results of this study indicate that BPS and three isomers of BPF, as alternatives to BPA, have higher mobility in saturated soils and may pose a substantial risk to groundwater quality. This study enhances our understanding of bisphenol analogs' behavior in natural soils, facilitating an assessment of their environmental implications, particularly regarding groundwater contamination.

Twelve natural estrogens and ten bisphenol analogues in eight drinking water treatment plants: Analytical method, their occurrence and risk evaluation

Bisphenol analogues (BPs) and natural estrogens (NEs) as two important groups of endocrine-disrupting compounds (EDCs) in drinking water treatment plants (DWTPs) have been hardly investigated except bisphenol A (BPA) and three major NEs including estrone (E1), 17β-estradiol (E2) and estriol (E3). In this study, a GC-MS analytical method was firstly established and validated for trace simultaneous determination of ten BPs and twelve NEs in drinking water, which included BPA, bisphenol B (BPB), bisphenol C (BPC), bisphenol E (BPE), bsiphenol F (BPF), bsiphenol P (BPP), bisphenol S (BPS), bisphenol Z (BPZ), bisphenol AF (BPAF), bisphenol AP (BPAP), E1, E2, E3, 17α-estradiol (17α-E2), 2-hydroestrone (2OHE1), 16hydroxyestrone (16α-OHE1), 4-hydroestrone (4OHE1), 2-hydroxyesstradiol (2OHE2), 4-hydroxyestradiol (4OHE2), 17-epiestriol (17epiE3), 16-epiestriol (16epiE3) and 16keto-estraiol (16ketoE2). This investigation showed that eighteen out of twenty-two targeted compounds were detected in drinking source waters of eight DWTPs with concentrations ranging from not detected to 142.8 ng/L. Although the conventional treatment process of DWTP could efficiently remove both BPs and NEs with respective removal efficiencies of 74.1%-90.9% and 74.5%-100%, BPA, BPS, BPE, BPZ, E1, 2OHE1, and 2OHE2 were found in the finished drinking waters. Chlorination could remove part of BPs and NEs, but the efficiency varied greatly with DWTP and the reason was unknown. In the finished drinking waters of eight DWTPs, the highest chemically calculated estrogen equivalence (EEQ) derived from BPs and NEs was up to 6.11 ngE2/L, which was over 22 times that could do harm to zebrafish, indicating a potential risk to human health. Given the fact that many chlorination products of BPs and NEs likely have higher estrogenic activities, the estrogenic effect of BPs and NEs in finished drinking water should be accurately examined urgently with the inclusion of BPs, NEs as well as their main chlorinated by-products. This study shed new light on the occurrence, removal, and potential estrogenic effects of BPs and NEs in DWTPs.

Large-scale comparative analysis reveals different bacterial community structures in full- and lab-scale wastewater treatment bioreactors

The activated sludge process is widely used for biological wastewater treatment due to its low cost and high efficiency. Although numerous lab-scale bioreactor experiments have been conducted to investigate the microorganism performance and mechanisms in activated sludge, understanding the bacterial community differences between full- and lab-scale bioreactors has remained elusive. In this study, we investigated the bacterial communities in 966 activated sludge samples obtained from various bioreactors, including both full- and lab-scale ones, from 95 previous studies. Our findings reveal significant differences in the bacterial communities between full- and lab-scale bioreactors, with thousands of bacterial genera exclusive to each scale. We also identified 12 genera that are frequently abundant in full-scale bioreactors but rarely observed in lab-scale reactors. By using a machine-learning method, organic matter and temperature were determined as the primary factors affecting microbial communities in full- and lab-scale bioreactors. Additionally, transient bacterial species from other environments may also contribute to the observed bacterial community differences. Furthermore, the bacterial community differences between full- and lab-scale bioreactors were verified by comparing the results of lab-scale bioreactor experiments to full-scale bioreactor sampling. Overall, this study sheds light on the bacteria overlooked in lab-scale studies and deepens our understanding of the differences in bacterial communities between full- and lab-scale bioreactors.

Acute exposure to realistic concentrations of Bisphenol-A trigger health damage in fish: Blood parameters, gene expression, oxidative stress

Despite much information regarding BPA toxicity in fish and other aquatic organisms, data is still misleading as most studies have utilized concentrations several orders of magnitude higher than those typically found in the environment. As an illustration, eight of the ten studies investigating the impact of BPA on the biochemical and hematological parameters of fish have employed concentrations on the order of mg/L. Therefore, the results may not accurately represent the effects observed in the natural environment. Considering the information above, our study aimed to 1) determine whether or not realistic concentrations of BPA might alter the biochemical and blood parameters of Danio rerio and trigger an inflammatory response in the fish liver, brain, gills, and gut and 2) determine which organ could be more affected after exposure to this chemical. Findings pinpoint that realistic concentrations of BPA prompted a substantial increase in antioxidant and oxidant biomarkers in fish, triggering an oxidative stress response in all organs. Likewise, the expression of different genes related to inflammation and apoptosis response was significantly augmented in all organs. Our Pearson correlation shows gene expression was closely associated with the oxidative stress response. Regarding blood parameters, acute exposure to BPA generated biochemical and hematological parameters increased concentration-dependent. Thus, it can be concluded that BPA, at environmentally relevant concentrations, threatens aquatic species, as it prompts polychromasia and liver dysfunction in fish after acute exposure.

Direct degradation of Bisphenol A from aqueous solution by active red mud in aerobic environment

As industrial waste from aluminum production, red mud (RM) poses a severe threat to the local environment that needs to be appropriately utilized. The activation of iron oxide, which is abundant in RM, improves its effectiveness as a catalytic material for the degradation of organic pollutants. This study developed a novel activation approach by adding dithionite citrate bicarbonate (DCB) for Bisphenol A (BPA) degradation under aeration conditions. Electrochemical experiments and reactive oxygen species (ROSs) trapping experiments showed that DCB treatment enhanced the redox cycle of Fe(II)/Fe(III), which promoted free radical generation. The optimized condition for the RM activation was achieved at 21 mmol/L dithionites, 84 mmol/L citrates, and 34 mmol/L bicarbonate, and the degradation of BPA by activated RM reached 410 µg BPA per gram of RM. This work provided a feasible way to utilize RM resources as an efficient, low-cost catalyst for organic pollutants treatment.

Bioaccumulation, internal distribution and toxicity of bisphenol S in the earthworm Eisenia fetida

Due to the strict rules and restrictions on the utilization of bisphenol A (BPA) around the world, an emerging endocrine disrupting chemical, bisphenol S (BPS) has been widely utilized as a substitute and frequently detected in the environment, even in the human body. Although it has been widely studied in the aquatic systems, the fate and toxicological effect of BPS in soil invertebrates are poorly known. This study presented a comprehensive exploration into the attenuation, bioaccumulation, and physiological distribution of BPS in an ecologically significant soil invertebrate, as well as its subsequent ecotoxicological effect to earthworm for the first time. The E. fetida could promote the BPS attenuation in soil, with degradation rates of 92.8 ± 1.6 % and 98.6 ± 1.1 % at dosage of 1.0 mg/kg dry weight soil (DWS) and 0.1 mg/kg DWS, respectively. The bioaccumulation of BPS in the earthworm was up to 111.6 ± 6.0 mg/kg lipid and 12.9 ± 2.9 mg/kg lipid with the initial dosage of 1.0 mg/kg DWS and 0.1 mg/kg DWS, respectively. Furthermore, BPS could induce oxidative stress and the process of antioxidant defense in earthworm cells at relatively high dose (1.0 mg/kg DWS and 10.0 mg/kg DWS), suggesting potential risks of BPS to the soil environment. This study could contribute to a more in-depth understanding of the fate of BPS in soil-earthworm system, and indicate a necessity for better understanding the environmental fate and ecological risks of BPA substitutes in the future.

Construction of dual Z-scheme Bi2WO6/g-C3N4/black phosphorus quantum dots composites for effective bisphenol A degradation

In this work, a novel dual Z-scheme Bi₂WO₆/g-C₃N₄/black phosphorus quantum dots (Bi₂WO₆/g-C₃N₄/BPQDs) composites were fabricated and utilized towards photocatalytic degradation of bisphenol A (BPA) under visible-light irradiation. Optimizing the content of g-C₃N₄ and BPQDs in Bi₂WO₆/g-C₃N₄/BPQDs composites to a suitable mass ratio can enhance the visible-light harvesting capacity and increase the charge separation efficiency and the transfer rate of excited-state electrons and holes, resulting in much higher photocatalytic activity for BPA degradation (95.6%, at 20 mg/L in 120 min) than that of Bi₂WO₆ (63.7%), g-C₃N₄ (25.0%), BPQDs (8.5%), and Bi₂WO₆/g-C₃N₄ (79.6%), respectively. Radical trapping experiments indicated that photogenerated holes (h⁺) and superoxide radicals (•O₂^-) played crucial roles in photocatalytic BPA degradation. Further, the possible degradation pathway and photocatalytic mechanism was proposed by analyzing the BPA intermediates. This work also demonstrated that the Bi₂WO₆/g-C₃N₄/BPQDs as effective photocatalysts was stable and have promising potential to remove environmental contaminants from real water samples.

Ten bisphenol analogs were abundantly found in swine and bovine urines collected from two Chinese farms: concentration profiles and risk evaluation

Bisphenol analogs (BPs) in livestock urine are important biomarkers to reflect the potential contaminants in food products derived from these animals. Nevertheless, little research has been done on their occurrence in farm animal urine. This work investigated ten BPs in swine and bovine urines collected from two Chinese farms. Results showed that all of these ten BPs were frequently detected in swine and bovine urines. The total mean concentration of the ten BPs (ΣBPs) in sow urines was 59.7 ng/mL, which was significantly higher than that of the boar urine with a mean concentration of 37.0 ng/mL (p < 0.05). On the other hand, the corresponding mean concentration of ΣBPs in dairy cattle urine was 59.6 ng/mL, which was significantly higher than that of the beef cattle urine with 37.0 ng/mL (p < 0.05). The respective mean concentration contribution ratios of BPA to ΣBPs in boar, sow, dairy, and beef cattle urines were only 14.9%, 21.4%, 9.0%, and 14.6%, which clearly indicated that BPA was no longer the dominant BP. The average daily urinary excretion rates of ΣBPs by boar, sow, dairy, and beef cattle were 37.0, 59.8, 167.0, and 36.8 times that of human, which suggested that swine and bovine likely encountered high dosage exposure of BPs in the two Chinese livestock farms. Our results showed that feeds and nutritional supplements as unintentionally added contaminants were the main sources of BPs to swine and bovine. As swine and bovine are important food sources for human being, part of BPs exposed to livestock eventually would enter human body via meat or milk. Therefore, quality controls of these feeds or nutritional supplements are quite important in order to guarantee welfare of livestock as well as protect health of our human beings.

Bisphenol F induces liver-gut alteration in zebrafish

The unease of consumers with bisphenol A has led to the increased industrial usage of bisphenol F (BPF), which is a new hazard to environmental health. Here, zebrafish were exposed to three BPF concentrations (0.5, 5, and 50 μg/L) from the embryonic stage for 180 days. Results showed that zebrafish body length and weight decreased and hepatosomatic index values increased, even at environmentally relevant concentration. Histological analysis identified the occurrence of hepatic fibrosis and steatosis in 5 and 50 μg/L groups, which indicated the liver injury caused by BPF. Based on the untargeted metabolomics results, a dose-dependent variation in the effects of BPF on liver metabolism was found, and amino acids, purines and one carbon metabolism were the main affected processes in the 0.5, 5, and 50 μg/L treatments, respectively. At the same time, BPF induced a shift in intestinal microbiome composition, including decreased abundance of Erysipelotrichaceae, Rhodobacteraceae and Gemmobacter. In addition, the correlation analysis suggested an association between gut microbiome changes and affected hepatic metabolites after BPF exposure. These findings indicate that a liver-gut alteration is induced by long-term BPF exposure.

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.

Reactions of bisphenol F and bisphenol S with ozone and hydroxyl radical: Kinetics and mechanisms

Bisphenol F (BPF) and bisphenol S (BPS) are the most employed substitutes of bisphenol A (BPA), after being restricted by legislation in different countries because of its endocrine disrupting behaviour. In the present work, a deep study was performed about the reactivity of BPF and BPS with ozone and hydroxyl radical. Firstly, the second order rate constants of ozone with the di-protonated, mono-protonated and deprotonated species of both bisphenols were determined to be 2.38 × 10⁴, 1.31 × 10⁹ and 1.43 × 10⁹ M^-1 s^-1 for BPF and 5.01, 2.82 × 10⁷ and 1.09 × 10⁹ M^-1 s^-1 for BPS. Then, the second order rate constants for the reaction of hydroxyl radical with BPF and BPS were established through UV/H₂O₂ and UV experiments at pH 7, resulting in the values of 8.60 × 10⁹ and 6.60 × 10⁹ M^-1 s^-1, respectively. Finally, a study regarding the transformation products (TPs) from the reaction of both bisphenols with molecular ozone and hydroxyl radical was also performed. Hydroxylation in the ortho position of the phenol rings was observed as main degradation pathway. Additionally, most of the TPs were accumulated over the reactions at relatively high oxidant doses.

Bacterial degradation of bisphenol analogues: an overview

Bisphenol A (BPA) is one of the most produced synthetic monomers in the world and is widespread in the environment. BPA was replaced by bisphenol analogues (BP) because of its adverse effects on life. Bacteria can degrade BPA and other bisphenol analogues (BP), diminishing their environmental concentrations. This study aimed to summarize the knowledge and contribute to future studies. In this review, we surveyed papers on bacterial degradation of twelve different bisphenol analogues published between 1987 and June 2022. A total of 102 original papers from PubMed and Google Scholar were selected for this review. Most of the studies (94.1%, n = 96) on bacterial degradation of bisphenol analogues focused on BPA, and then on bisphenol F (BPF), and bisphenol S (BPS). The number of studies on bacterial degradation of bisphenol analogues increased more than six times from 2000 (n = 2) to 2021 (n = 13). Indigenous microorganisms and the genera Sphingomonas, Sphingobium, and Cupriavidus could degrade several BP. However, few studies focussed on Cupriavidus. The acknowledgement of various aspects of BP bacterial biodegradation is vital for choosing the most suitable microorganisms for the bioremediation of a single BP or a mixture of BP.

Removal of microorganic pollutants in aquatic environment: The utilization of Fe(VI)

Microorganic pollutants (MOPs) in aquatic environment with low levels but high toxicity are harmful to ecosystem and human health. Fe(VI) has a dual-functional role in oxidation and coagulation, and can effectively remove MOPs, heavy metal, phosphate, particulates and colloids. Moreover, Fe(VI) can combine with traditional coagulants, or use as a pretreatment for membrane treatment because of its characters to generate nanoparticles by degradation in water. Based on the relevant toxicity experiments, Fe(VI) had been proved to be safe for the efficient treatment of MOPs. For better utilization of Fe(VI), its oxidation and coagulation mechanisms are summarized, and the knowledge about the control parameters, utilization methods, and toxicity effect for Fe(VI) application are reviewed in this paper. pH, different valences of iron, environmental substances, and other parameters are summarized in this study to clarify the important factors in the treatment of MOPs with Fe(VI). In the future study, aiming at cost reduction in Fe(VI) preparation, transportation and storage, enhancement of oxidation in the intermediate state, and better understanding the mechanism between interface and Fe(VI) oxidation will help promote the application of Fe(VI) in the removal of MOPs. This study offers guidelines for the application and development of Fe(VI) for the treatment of MOPs in aquatic environment.

Strongly enhanced Fenton-like oxidation (Fe/peroxydisulfate) by BiOI under visible light irradiation: A novel and green strategy for Fe(III) reduction

In order to accelerate the photo-Fenton reaction process of Fe(III) under visible light irradiation, BiOI was introduced into the Fe(III)/peroxydisulfate (PDS) system. The catalytic oxidation performance of vis-light/BiOI/Fe(III)/PDS system was evaluated using bisphenol AF (BPAF) as a representative organic contaminant. Within 30 min, nearly 100% of BPAF was degraded, proving that the system had an excellent ability to degrade organic pollutants in water. Free radical quenching experiments, electron spin resonance (ESR), and molecular probing experiments determined that the main reactive species in the system were hydroxyl radicals (^•OH) and sulfate radicals (SO₄^•-). The comparative experiments showed that the degradation rates were closely related to the PDS consumption, while the Fe(II) absorbed on the surface of BiOI was responsible for the PDS consumption. The production pathway of Fe(II) was analyzed by XRD, FTIR and XPS characterization, the Fe(III) on the surface of BiOI was reduced by photogenerated electrons to generate Fe(II). The result confirmed that the reduction of Fe(III) by photogenerated electrons could effectively inhibit the recombination of electron-hole pairs, and accelerate the reduction progress of Fe(III)/Fe(II) cycle that was the rate-limiting step in PDS activation. Afterwards, a reliable mechanism for degradation of BPAF in visible light/BiOI/Fe(III)/PDS system was proposed. Finally, the influence of reactant dosages, visible light intensity, initial pH, humic acid (HA) and anions in the solution on the degradation of BPAF were discussed.

Overlooked environmental risks deriving from aqueous transformation of bisphenol alternatives: Integration of chemical and toxicological insights

Owing to the widespread prevalence and ecotoxicity of bisphenol alternatives such as bisphenol S, bisphenol F, and bisphenol AF, the past decade has witnessed the publication of a remarkable number of studies related to their transformation and remediation in natural waters. However, the reactivity, removal efficiency, transformation products (TPs), and mechanisms of such emerging pollutants by different treatment processes have not been well elucidated. Particularly, the transformation-driven environmental risks have been mostly overlooked. Therefore, we present a review to address these issues from chemical and toxicological viewpoints. Four degradation systems can be largely classified as catalytic persulfate (PS) oxidation, non-catalytic oxidation, photolysis and photocatalysis, and biodegradation. It was found that bisphenol alternatives possess distinct reactivities with different oxidizing species, with the highest performance for hydroxyl radicals. All systems exhibit superior elimination efficiency for these compounds. The inadequate mineralization suggests the formation of recalcitrant TPs, from which the overall reaction pathways are proposed. The combined experimental and in silico analysis indicates that many TPs have developmental toxicity, endocrine-disrupting effects, and genotoxicity. Notably, catalytic PS systems and non-catalytic oxidation result in the formation of coupling products as well as halogenated TPs with higher acute and chronic toxicity and lower biodegradability than the parent compounds. In contrast, photolysis and photocatalysis generate hydroxylated and bond-cleavage TPs with less toxicity. Overall, this review highlights the secondary environmental risks from the transformation of bisphenol alternatives by conventional and emerging treatment processes. Finally, future perspectives are recommended to address the knowledge gaps of these contaminants in aquatic ecosystems.

Removal and fate of 18 bisphenols in lab-scale algal bioreactors

The removal of 18 bisphenols at wastewater relevant concentrations (μg L^-1 range) was investigated and compared between Chlorella vulgaris cultures with pH adjusted to 6.8 and pH non-adjusted cultures where pH raised to above 10. Bisphenols with a high partition coefficient (log P > 6) partitioned to biomass soon after spiking, whereas bisphenols with a low partition coefficient (log P < 4) remained largely in the aqueous phase. Hydrophobic bisphenols and BPF isomers were removed to a large degree in pH adjusted conditions, while BPS and BPAF were the most recalcitrant. The overall average removal after 13 days was similar in both experiments, with 72 ± 2% and 73 ± 5% removed in pH non-adjusted and pH adjusted series, respectively. The removal correlated with chlorophyll a concentration for most bisphenols meaning that algae played a crucial role in their removal, while culture pH also governed the removal of some compounds.

Occurrence, distribution, and risk assessment of bisphenol analogues in Luoma Lake and its inflow rivers in Jiangsu Province, China

Bisphenol analogs (BPs) are widely used in industrial and commercial products and have been detected in surface water, sediment, sewage, and sludge. The presence of BPs in the natural environment poses threats to the aquatic ecosystem and human health. The concentration, distribution, seasonal variation, and risk assessment of BPA and BPA structural analogs including BPB, BPF, BPS, BPZ, BPAF, and BPAP in surface water and sediment during dry season and flood season in Luoma Lake and its inflow rivers in Jiangsu Province, China, were investigated in this study. The detection frequency of BPA and BPF was 100%. Although the use of BPA is restricted, BPA is still the dominant BPs in surface water and sediment. The concentration of BPs in surface water during flood season was higher than that in dry season. The concentrations of BPs in Fangting River, Zhongyun River, and Bulao River were higher than those in Luoma Lake. The average concentrations of BPs in surface water were in the order of BPA > BPF> BPS> BPB > BPZ > BPAF> BPAP. Compared with other studies, the concentration of BPs in Luoma Lake was moderate. There is no significant spatial distribution and difference in seasonal variation of BPs concentration in sediment (p > 0.05). Compared with other studies, the contamination of BPs in sediment of Luoma Lake was relatively low. Risk quotient (RQ) was used to evaluate the ecological risk of BPs in water environment, and the 17β estradiol equivalent (EEQ) method was used to estimate the estrogenic activity of BPs. The risk assessment showed no high ecological risk (RQ < 1.0) and estrogenic risk (EEQ < 1.0 ng/L) in dry season and flood season. The estimated RQ and EEQ_t indicated that the ecological and human health impacts were negligible in the short term.

An overview of the literature on emerging pollutants: Chlorinated derivatives of Bisphenol A (ClxBPA)

CONTEXT

Bisphenol A (BPA) is a ubiquitous contaminant with endocrine-disrupting effects in mammals. During chlorination treatment of drinking water, aqueous BPA can react with chlorine to form chlorinated derivatives of BPA (mono, di, tri and tetra-chlorinated derivatives) or Cl_xBPA.

OBJECTIVE

The aim of this study is to summarize and present the state of knowledge on human toxicological risk assessment of Cl_xBPA.

MATERIALS AND METHODS

A search on Cl_xBPA in the PubMed database was performed based on studies published between 2002 and 2021. Forty-nine studies on chlorinated derivatives of BPA were found. Available information on their sources and levels of exposure, their effects, their possible mechanisms of action and their toxicokinetics data was extracted and presented.

RESULTS

Cl_xBPA have been essentially detected in environmental aqueous media. There is evidence in toxicological and epidemiological studies that Cl_xBPA also have endocrine-disrupting capabilities. These emerging pollutants have been found in human urine, serum, breast milk, adipose and placental tissue and can constitute a risk to human health. However, in vitro and in vivo toxicokinetic data on Cl_xBPA are scarce and do not allow characterization of the disposition kinetics of these compounds.

CONCLUSION

More research to assess their health risks, specifically in vulnerable populations, is needed. Some water chlorination processes are particularly hazardous, and it is important to evaluate their chlorination by-products from a public health perspective.

Occurrence, Profiles and Ecological Risk of Bisphenol Analogues in a Municipal Sewage Treatment Plant

Due to the strict control on bisphenol A (BPA) in many countries, bisphenol analogues (BPs) are being widely used as alternative materials to manufacture epoxy resins and polycarbonate plastics, resulting in their occurrence in sewage treatment plants (STPs). In this study, the occurrence and distribution of 7 BPs in a large-scale STP in Beijing China was investigated. Wastewater samples were collected from the influents and effluents of each processing unit, and extracted by solid-phase extraction. Target compounds were quantified by ultra-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The total concentrations of seven BPs (ΣBPs) were 400.42 ± 48.12 ng/L in the raw sewage, 438.60 ± 46.50 ng/L in the primary effluent, 17.21 ± 13.12 ng/L in the secondary effluent, and 11.33 ± 4.84 ng/L in the tertiary effluent, respectively. Bisphenol S (BPS) and BPA were the predominant congener in raw sewage with an overall contribution of 29.32% and 70.22% to the ΣBPs, indicating that there was a large amount of BPS and BPA consumption in the study area. During a one-week sampling period, ΣBPs changed slightly at the same sampling site. It was found that high removal efficiencies were achieved for BPs in anoxic and oxic secondary clarifier treatment units, suggesting that biodegradation and sorption played major roles in BPs elimination in the STP. After tertiary treatment, all BPs except BPA were completely removed, suggesting the necessity to investigate the fate and toxicity of BPA in the aquatic environment.