Aerobic Soil Biodegradation of Bisphenol (BPA) Alternatives Bisphenol S and Bisphenol AF Compared to BPA

Oxidation-reduction process of Arabidopsis thaliana roots induced by bisphenol compounds based on RNA-seq analysis

Bisphenol compounds (BPs) have various industrial uses and can enter the environment through various sources. To evaluate the ecotoxicity of BPs and identify potential gene candidates involved in the plant toxicity, Arabidopsis thaliana was exposed to bisphenol A (BPA), BPB, BPE, BPF, and BPS at 1, 3, 10 mg/L for a duration of 14 days, and their growth status were monitored. At day 14, roots and leaves were collected for internal BPs exposure concentration detection, RNA-seq (only roots), and morphological observations. As shown in the results, exposure to BPs significantly disturbed root elongation, exhibiting a trend of stimulation at low concentration and inhibition at high concentration. Additionally, BPs exhibited pronounced generation of reactive oxygen species, while none of the pollutants caused significant changes in root morphology. Internal exposure concentration analysis indicated that BPs tended to accumulate in the roots, with BPS exhibiting the highest level of accumulation. The results of RNA-seq indicated that the shared 211 differently expressed genes (DEGs) of these 5 exposure groups were enriched in defense response, generation of precursor metabolites, response to organic substance, response to oxygen-containing, response to hormone, oxidation-reduction process and so on. Regarding unique DEGs in each group, BPS was mainly associated with the redox pathway, BPB primarily influenced seed germination, and BPA, BPE and BPF were primarily involved in metabolic signaling pathways. Our results provide new insights for BPs induced adverse effects on Arabidopsis thaliana and suggest that the ecological risks associated with BPA alternatives cannot be ignored.

National investigation of bisphenols in the surface soil in China

The long-term production and extensive use have resulted in the widespread presence of bisphenols (BPs) in the environment. In order to clarify the pollution characteristics and potential sources of BPs, the national scale surface soil samples were collected in China in 2019. The results demonstrated that 32 target BPs existed widely in soil with the highest concentration for bisphenol A (BPA), and at least 2 BPs were detected in each sample. The total concentration of Σ32BPs (from 0.387 to 713 ng/g) exhibited a stepwise decrease from southeastern coast to inland regions, and due to the presence of more pollution sources concentrations of Σ32BPs in urban areas were slightly higher than rural areas. The different industrial structures (such as plastics, epoxy resins, and thermal paper) may be the important factors for the different pollution levels between southeastern coast and other regions. In addition, the high organic matter content in soil and low temperature may be the reasons for high concentrations of Σ32BPs in Northeast China. The results of source identification using the Positive Matrix Factorization model indicated that BPs in soil were originated from three sources: old sources represented by BPA, relatively new sources characterized by bisphenol S, and sources from specific industries using bisphenol F. The estimated daily intake indicated that BPA exposure through soil accounted for only a small proportion of the total exposure compared to other exposure routes, and the risk by BPA in soil can be negligible to human health. In summary, the study provided basic pollution information of BPs in Chinese surface soil for future related studies.

Bacterial bioremediation as a sustainable strategy for the mitigation of Bisphenol-A

In the era dominated by plastic, the widespread use of plastic in our daily lives has led to a growing accumulation of its degraded byproducts, such as microplastics and plastic additives like Bisphenol A (BPA). BPA is recognized as one of the earliest man-made substances that exhibit endocrine-disrupting properties. It is frequently employed in the manufacturing of epoxy resins, polycarbonates, dental fillings, food storage containers, infant bottles, and water containers. BPA is linked to a range of health issues including obesity, diabetes, chronic respiratory illnesses, cardiovascular diseases, and reproductive abnormalities. This study examines the bacterial bioremediation of the BPA, which is found in many sources and is known for its hazardous effects on the environment. The metabolic pathways for the breakdown of BPA in important bacterial strains were hypothesized based on the observed altered intermediate metabolites during the degradation of BPA. This review discusses the enzymes and genes involved in the bacterial degradation of BPA. The utilization of naturally occurring microorganisms is the most efficient and cost-effective method due to their selectivity of strains, ensuring sustainability.

Biochar supported Pseudomonas putida based globules for effective removal of Bisphenol A with a practical approach

The widespread and inevitable use of plastic has led to prospective ecological problems through Bisphenol A (BPA), a synthetic chemical in plastic manufacturing. The present study addresses a unique methodology for eliminating BPA using the assistance of Pseudomonas putida. In the present work, biomass was torrefied to generate biochar with highly porous networks that could accommodate the bacterial species for effective colonization and multiplication. The designed biochar-bacterial globules demonstrated the ability to effectively remove BPA (96.88%) at a concentration of up to 2 g/L. The biochar-bacterial globules could effectively adsorb BPA at a low concentration of 20 mg/L. The alteration in pH did not impact the globule's performance, providing additional support for the practical utilization of these globules in polluted water bodies. In addition, the biochar-bacterial globules exhibited superior effectiveness in degradation compared to the standard levels, particularly in saline conditions. The simplicity and effectiveness of the approach make it promising for real-world implementation in addressing ecological problems associated with BPA contamination.

In situ construction of Ag/Bi2O3/Bi5O7I heterojunction with Bi-MOF for enhance the photocatalytic efficiency of bisphenol A by facet-coupling and s-scheme structure

In this study, Ag/Bi2O3/Bi5O7I with s-scheme heterostructures were successfully synthesized in situ by nano-silver modification of CUA-17 and halogenated hydrolysis.The growth rate of Bi2O3 crystals was effectively controlled by adjusting the doping amount of Ag, resulting in the formation of a facet-coupling heterojunctions. Through the investigation of the microstructure and compositional of catalysts, it has been confirmed that an intimate facet coupling between the Bi2O3 (120) facet and the Bi5O7I (312) facet, which provides robust support for charge transfer. Under visible light irradiation, the AgBOI.3 heterojunction photocatalyst exhibited an outstanding degradation rate of 98.2% for Bisphenol A (BPA) with excellent stability. Further characterization using optical, electrochemical, impedance spectroscopy, and electron spin resonance techniques revealed significantly enhanced efficiency in photogenerated charge separation and transfer, and confirming the s-scheme structure of the photocatalyst. Density functional theory calculations was employed to elucidate the mechanism of BPA degradation and the degradation pathway of BPA was investigated by LC-MS. Finally, the toxicity of the degradation intermediates was evaluated using T.E.S.T software.

Toxic effects of environmental concentration Bisphenol AF exposure on the survival, growth and reproduction of adult male Oryzias curvinotus

Bisphenol AF (BPAF) is a novel environmental endocrine disruptor, and is widely detected in the aquatic environment, which is a potential threat to the health of fish. In this study, male Oryzias curvinotus were exposed to environmental concentrations (0.93 and 9.33 μg/L) of BPAF for 21 days. The effects of BPAF on survival, growth, reproduction, liver and testis histology, and gene transcriptional profiles of O. curvinotus were investigated. The results showed that the survival rate of male O. curvinotus slight decrease with increasing BPAF concentration, and there was no significant effect on body length, body weight, and K-factor. BPAF (9.33 μg/L) caused significant changes in testicular structure and reduced spermatid count in O. curvinotus. Changes in transcript levels of some antioxidant-related genes in gills and liver following BPAF exposure, imply an effect of BPAF on the immune system. After BPAF exposure, chgs and vtgs were up-regulated, validating the estrogenic effect of BPAF. In the hypothalamic - pituitary - gonadal axis (HPG) results, erα, erγ and cyp19a1b were all up-regulated in the brain, and the 0.93 μg/L BPAF group was more up-regulated than the 9.33 μg/L BPAF group. In testis, BPAF significantly up-regulated the mRNA expression level of cyp17a1 and cyp11b, while significantly down-regulated mRNA expression level of cyp11a, and cyp19a1 was significantly down-regulated only in the 0.93 μg/L BPAF group. In conclusion, environmental levels of BPAF have adverse effects on the survival and reproduction of O. curvinotus, and the potential toxic effects of environmental levels of BPAF cannot be ignored.

The Impact of Bisphenol A on the Anaerobic Sulfur Transformation: Promoting Sulfur Flow and Toxic H2S Production

Bisphenol A (BPA), as a typical leachable additive from microplastics and one of the most productive bulk chemicals, is widely distributed in sediments, sewers, and wastewater treatment plants, where active sulfur cycling takes place. However, the effect of BPA on sulfur transformation, particularly toxic H2S production, has been previously overlooked. This work found that BPA at environmentally relevant levels (i.e., 50-200 mg/kg total suspended solids, TSS) promoted the release of soluble sulfur compounds and increased H2S gas production by 14.3-31.9%. The tryptophan-like proteins of microbe extracellular polymeric substances (EPSs) can spontaneously adsorb BPA, which is an enthalpy-driven reaction (ΔH = -513.5 kJ mol-1, ΔS = -1.60 kJ mol-1K -1, and ΔG = -19.52 kJ mol-1 at 35 °C). This binding changed the composition and structure of EPSs, which improved the direct electron transfer capacity of EPSs, thereby promoting the bioprocesses of organic sulfur hydrolysis and sulfate reduction. In addition, BPA presence enriched the functional microbes (e.g., Desulfovibrio and Desulfuromonas) responsible for organic sulfur mineralization and inorganic sulfate reduction and increased the abundance of related genes involved in ATP-binding cassette transporters and sulfur metabolism (e.g., Sat and AspB), which promoted anaerobic sulfur transformation. This work deepens our understanding of the interaction between BPA and sulfur transformation occurring in anaerobic environments.

Long-term push-pull cropping system shifts soil and maize-root microbiome diversity paving way to resilient farming system

BACKGROUND

The soil biota consists of a complex assembly of microbial communities and other organisms that vary significantly across farming systems, impacting soil health and plant productivity. Despite its importance, there has been limited exploration of how different cropping systems influence soil and plant root microbiomes. In this study, we investigated soil physicochemical properties, along with soil and maize-root microbiomes, in an agroecological cereal-legume companion cropping system known as push-pull technology (PPT). This system has been used in agriculture for over two decades for insect-pest management, soil health improvement, and weed control in sub-Saharan Africa. We compared the results with those obtained from maize-monoculture (Mono) cropping system.

RESULTS

The PPT cropping system changed the composition and diversity of soil and maize-root microbial communities, and led to notable improvements in soil physicochemical characteristics compared to that of the Mono cropping system. Distinct bacterial and fungal genera played a crucial role in influencing the variation in microbial diversity within these cropping systems. The relative abundance of fungal genera Trichoderma, Mortierella, and Bionectria and bacterial genera Streptomyces, RB41, and Nitrospira were more enriched in PPT. These microbial communities are associated with essential ecosystem services such as plant protection, decomposition, carbon utilization, bioinsecticides production, nitrogen fixation, nematode suppression, phytohormone production, and bioremediation. Conversely, pathogenic associated bacterial genus including Bryobacter were more enriched in Mono-root. Additionally, the Mono system exhibited a high relative abundance of fungal genera such as Gibberella, Neocosmospora, and Aspergillus, which are linked to plant diseases and food contamination. Significant differences were observed in the relative abundance of the inferred metabiome functional protein pathways including syringate degradation, L-methionine biosynthesis I, and inosine 5'-phosphate degradation.

CONCLUSION

Push-pull cropping system positively influences soil and maize-root microbiomes and enhances soil physicochemical properties. This highlights its potential for agricultural and environmental sustainability. These findings contribute to our understanding of the diverse ecosystem services offered by this cropping system where it is practiced regarding the system's resilience and functional redundancy. Future research should focus on whether PPT affects the soil and maize-root microbial communities through the release of plant metabolites from the intercrop root exudates or through the alteration of the soil's nutritional status, which affects microbial enzymatic activities.

Fate and transformation of uniformly 14C-ring-labeled bisphenol S in different aerobic soils

Bisphenol S (BPS), being structurally similar to bisphenol A (BPA), has been widely used as an alternative to BPA in industrial applications. However, in-depth studies on the environmental behavior and fate of BPS in various soils have been rarely reported. Here, 14C-labeled BPS was used to investigate its mineralization, bound residues (BRs) formation and extractable residues (ERs) in three soils for 64 days. Significant differences were found in the dissipation rates of BPS in three soils with different pH values. The dissipation of BPS followed pseudo first-order kinetics with half-lives (T1/2) of 15.2 ± 0.1 d, 27.0 ± 0.2 d, 180.4 ± 5.3 d, and 280.5 ± 3.3 d in the alkaline soil (fluvo-aquic soil, FS), the neutral soil (cinnamon soil, CS), the acidic soil (red soil, RS), and sterilized cinnamon soil (CS-S), respectively. The mineralization and BRs formation contributed the most to the dissipation of BPS in soil. BPS was persistent in acidic soil, and may pose a significant threat to plants grown in acidic soils. Additionally, soil microorganisms played a key role in BPS degradation, and the organic matter content might be a major factor that promotes the adsorption and degradation of BPS in soils. Two transformed products, P-hydroxybenzenesulfonic acid and methylated BPS were identified in soils. This study provides new insights into the fate of BPS in various soils, which will be useful for risk assessments of BPS in soil.

Bisphenols-A Threat to the Natural Environment

Negative public sentiment built up around bisphenol A (BPA) follows growing awareness of the frequency of this chemical compound in the environment. The increase in air, water, and soil contamination by BPA has also generated the need to replace it with less toxic analogs, such as Bisphenol F (BPF) and Bisphenol S (BPS). However, due to the structural similarity of BPF and BPS to BPA, questions arise about the safety of their usage. The toxicity of BPA, BPF, and BPS towards humans and animals has been fairly well understood. The biodegradability potential of microorganisms towards each of these bisphenols is also widely recognized. However, the scale of their inhibitory pressure on soil microbiomes and soil enzyme activity has not been estimated. These parameters are extremely important in determining soil health, which in turn also influences plant growth and development. Therefore, in this manuscript, knowledge has been expanded and systematized regarding the differences in toxicity between BPA and its two analogs. In the context of the synthetic characterization of the effects of bisphenol permeation into the environment, the toxic impact of BPA, BPF, and BPS on the microbiological and biochemical parameters of soils was traced. The response of cultivated plants to their influence was also analyzed.

Transcriptomics-based analysis of sex-differentiated mechanisms of hepatotoxicity in zebrafish after long-term exposure to bisphenol AF

Bisphenol AF (BPAF) is an emerging endocrine-disrupting chemical (EDC) prevalent in the environment as one of the main substitutes for bisphenol A. Sex-specific effects of EDCs have been commonly reported and closely linked to sexually dimorphic patterns of hormone metabolism and related gene expression during different exposure windows, but our understanding of these mechanisms is still limited. Here, following 28-day exposure of adult zebrafish to an environmentally relevant concentration of BPAF at 10 μg/L, the global transcriptional networks applying RNA sequencing (RNA-seq) and Ingenuity Pathway Analysis (IPA) were respectively investigated in the male and female fish liver, connecting the sex-dependent toxicity of the long-term exposure of BPAF to molecular responses. As a result, more differentially expressed genes (DEGs) were detected in males (811) than in females (195), and spermatogenesis was the most enriched Gene Ontology (GO) functional classification in males, while circadian regulation of gene expression was the most enriched GO term in females. The expression levels of selected DEGs were routinely verified using qRT-PCR, which showed consistent alterations with the transcriptional changes in RNA-seq data. The causal network analysis by IPA suggested that the adverse outcomes of BPAF in males including liver damage, apoptosis, inflammation of organ, and liver carcinoma, associated with the regulation of several key DEGs detected in RNA-seq, could be linked to the activation of upstream regulatory molecules ifnα, yap1, and ptger2; while, the inhibition of upstream regulators hif1α, ifng, and igf1, leading to the down-regulated expression of several key DEGs, might be involved in BPAF's effects in females. Furthermore, BPAF exposure altered hepatic histological structure and inhibited antioxidant capability in both male and female livers. Overall, this study revealed different regulation networks involved in the sex-dependent effects of BPAF on the fish liver, and these detected DEGs upon BPAF exposure might be used as potential biomarkers for further assessing sex-specific hepatotoxicity following environmental EDC exposure.

Mn(III)-mediated bisphenol a degradation: Mechanisms and products

Bisphenol A (BPA) is a high production volume chemical with potential estrogenic effects susceptible to abiotic degradation by MnO₂. BPA transformation products and reaction mechanisms with MnO₂ have been investigated, but detailed process understanding of Mn(III)-mediated degradation has not been attained. Rapid consumption of BPA occurred in batch reaction vessels with 1 mM Mn(III) and 63.9 ± 0.7% of 1.76 ± 0.02 μmol BPA was degraded in 1 hour at circumneutral pH. BPA was consumed at 1.86 ± 0.09-fold higher rates in vessels with synthetic MnO₂ comprising approximately 13 mol% surface-associated Mn(III) versus surface-Mn(III)-free MnO₂, and 10-35% of BPA transformation could be attributed to Mn(III) during the initial 10-min reaction phase. High-resolution tandem mass spectrometry (HRMS/MS) analysis detected eight transformation intermediates in reactions with Mn(III), and quantum calculations proposed 14 BPA degradation products, nine of which had not been observed during MnO₂-mediated BPA degradation, suggesting mechanistic differences between Mn(III)- versus MnO₂-mediated BPA degradation. The findings demonstrate that both Mn(III) and Mn(IV) can effectively degrade BPA and indicate that surface-associated Mn(III) increases the reactivity of synthetic MnO₂, offering opportunities for engineering more reactive oxidized Mn species for BPA removal.

Bisphenol A monitoring during anaerobic degradation of papers with thermochromic prints in soil

Pseudoestrogene bisphenol A (BPA) can be important ingredient of thermochromic inks, increasingly used materials in thermal printing paper, security printing, advertising, design and as temperature indicators in medicine and food industry. BPA mass fraction in thermochromic inks can be up to several percent. Hence, disposal of items with thermochromic prints pose a risk of environmental pollution. In this work BPA mass fraction was monitored during anaerobic degradation of papers with thermochromic prints in soil in both matrices: papers and soil. The degradation conditions simulated deeper layers of waste at a landfill site. Six types of papers with prints of thermochromic ink containing 2% of BPA were subjected to anaerobic degradation over up to 150 days. Initial mass fractions of BPA in papers decreased form (126-460) μg/g to (<QL - 45) μg/g after 150 days. BPA amounts were reduced 10 to 50 times depending on the paper type: least for synthetic paper and most for wood-free coated. For soil analysis new HPLC-UV method was developed and validated. The method was linear from 0.75 ng/g to 0.6 μg/g of BPA in soil with correlation coefficient of 0.9994. Method precision was 4.4%, accuracy 83% and detection limit 0.9 ng/g. Expectedly, amount of BPA in soil was increasing during the experiment. Mass fractions of BPA in soil were from not detected in earlier stage of degradation to (4.9-23.2) ng/g after 150 days. Final BPA amounts in soil were similar to those found in industrial, urban and agricultural soils worldwide. Hence, BPA from papers with thermochromic prints was notably decomposed, and contaminated soil had the capacity to absorb and decompose BPA even under anaerobic conditions. After 150 days of anaerobic degradation, only up to 1.86% of BPA contained in paper prints was found in soil, whilst, on average, 4% of initial BPA remained in paper.

Sensitive determination of bisphenols in environmental samples by magnetic porous carbon solid-phase extraction combined with capillary electrophoresis

Bisphenol compounds exist widely in the environment and pose potential hazards to the environment and human health, which has aroused widespread concern. Therefore, there is an urgent need for an efficient and sensitive analytical method to enrich and determine trace bisphenols in environmental samples. In this work, magnetic porous carbon (MPC) was synthesized by one-step pyrolysis combined with a solvothermal method for magnetic solid-phase extraction of bisphenols. The structural properties of MPC were characterized by field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and saturation magnetization analysis. Its adsorption properties were evaluated by adsorption kinetics and adsorption isotherm studies. By optimizing the magnetic solid-phase extraction and capillary electrophoresis separation conditions, a capillary electrophoresis separation and detection method for four bisphenols was successfully constructed. The results showed that the detection limits of the proposed method for the four bisphenols were 0.71-1.65 ng/mL, the intra-day and inter-day precisions were 2.27-4.03% and 2.93-4.42%, respectively, and the recoveries were 87.68%-108.0%. In addition, the MPC could be easily recycled and utilized, and even if the magnetic solid-phase extraction was repeated 5 times, the extraction efficiency could still be kept above 75%.

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.

Mechanism of visible light enhances microbial degradation of Bisphenol A

Bisphenol A (BPA) is a toxic endocrine disruptor detected in various environments. Microbial metabolic/enzymatic degradation has been thought to be the main pathway for BPA attenuation in natural environments. In this study, we found that under visible light conditions, superoxide produced by bacteria was the main reason for the rapid removal of BPA, accounting for 57 % of the total removal rate. With visible light, the bacteria degraded BPA at a rate of 0.22 mg/L/d, and the total removal within 8 days reached 85 %, which is 4.7 times compared with that of dark culture. The intermediate product 4-iso-propenylphenol, which was considered as an end-product of microbial degradation of BPA in previous reports, was detected in large quantities at 24 h in culture but gradually decreased in our experiment. Community analysis suggested bacteria with aromatic hydrocarbon degradation ability were more enriched under light incubation. Moreover, the bacteria showed well degradation ability to various pharmaceutically active but nonbiodegradable compounds including diclofenac and fluoxetine, with a removal rate of 88 % and 20 %, respectively. Our study revealed the organic pollutant transformation pathway under the combined action of light and microorganisms, providing new insights into the microbial treatment of aromatic hydrocarbon pollutants.

Congener-Specific Uptake and Metabolism of Bisphenols in Carrot Cells: Dissipation Kinetics, Biotransformation, and Enzyme Responses

Food consumption has been considered a key pathway of bisphenol compound (BP) exposure for humans. However, there is a lack of evidence concerning their congener-specific behavior and metabolism in plants. Herein, we examined the uptake and metabolism of five BPs in plants using carrot cells. Bisphenol S (BPS) and bisphenol AF (BPAF) exhibited substantially lower dissipation rates in the cells than the other BPs, indicating a strong selectivity in the uptake and metabolism among bisphenol congeners. For a total of 23 metabolites of BPs, the predominant biotransformation pathways were found to be glycosylation, methoxylation, and conjugation, while hydroxylation, methylation, and glutathionylation were only observed for some BPs. The changes in the mRNA expression of cytochrome P450 (P450) and the activities of glycosyltransferase and glutathione S-transferase were remarkably higher in cells exposed to bisphenol F, bisphenol A, and bisphenol B than in cells exposed to BPS and BPAF, indicating congener specificity in their effects on enzymes and the associated biotransformation processes. Consequently, the potential congener-specific differences in plant uptake, metabolism, and accumulation must be considered when assessing the environmental risks posed by these commonly used plasticizers.

Perfluoroalkyl acid and bisphenol-A exposure via food sources in four First Nation communities in Quebec, Canada

OBJECTIVE

To document perfluoroalkyl acids (PFAA) and bisphenol-A (BPA) exposure in four First Nation communities in northern Quebec compared with the Canadian Health Measures Survey (CHMS Cycle 5 2016-2017) and examine the associations between dietary consumption and chemical exposure.

DESIGN

We used cross-sectional data from the JES-YEH! project conducted in collaboration with four First Nation communities in 2015. A FFQ collected information on diet, and PFAA and BPA were measured in biological samples. We used generalised linear models to test the associations between food intake and chemical biomarkers.

SETTING

Northern Quebec.

PARTICIPANTS

Youth aged 3-19 years (n 198).

RESULTS

Mean perfluorononanoic acid (PFNA) levels were significantly higher in JES-YEH! than CHMS, and BPA levels were higher among those aged 12-19 years compared with CHMS. Dairy products were associated with PFNA among Anishinabe and Innu participants (geometric mean ratio 95 % CI: 1·53 (95 % CI 1·03, 2·29) and 1·52 (95 % CI 1·05, 2·20), respectively). PFNA was also associated with ultra-processed foods (1·57 (95 % CI 1·07, 2·31)) among Anishinabe, and with wild fish and berries (1·44 (95 % CI 1·07, 1·94); 1·75 (95 % CI 1·30, 2·36)) among Innu. BPA was associated with cheese (1·72 (95 % CI 1·19, 2·50)) and milk (1·53 (95 % CI 1·02, 2·29)) among Anishinabe, and with desserts (1·71 (95 % CI 1·07, 2·74)), processed meats (1·55 (95 % CI 1·00, 2·38)), wild fish (1·64 (95 % CI 1·07, 2·49)) and wild berries (2·06 (95 % CI 1·37, 3·10)) among Innu.

CONCLUSIONS

These results highlight the importance of better documenting food-processing and packaging methods, particularly for dairy products, and their contribution to endocrine disruptors exposures as well as to promote minimally processed and unpackaged foods to provide healthier food environments for youth in Indigenous communities and beyond.

Bisphenol S degradation in soil and the dynamics of microbial community associated with degradation

Bisphenol S (BPS) has been widely applied as a replacement for BPA in industrial application, leading to the frequent detection in the environment. However, its impact on soil microbial communities has not been well reported. Here, effects of BPS exposure on soil microbial communities in the presence of polystyrene (PS) microplastics were revealed. Rapid degradation of BPS occurred with a degradation rate of up to 98.9 ± 0.001 % at 32 d. The presence of BPS reduced the diversity of soil microbial communities, and changed community structures. After BPS treatment, Proteobacteria, and its members Methylobacillus, Rhodobacteraceae and Mesorhizobium became dominant, and were considered as potential biomarkers indicating BPS contamination. Co-occurrence network analysis revealed the increased relationships of certain groups of microbes after BPS treatment. The resultant low stability and resilience towards environment disturbance of microbial community networks implied the biotoxicity of BPS towards soil ecosystems. The degradation and biotoxicity of BPS (p > 0.05) in soil was not affected by the presence of PS. Our findings showed that exposure to BPS could reshape soil microbial communities and impair the robustness of microbial co-occurrence networks.

Phytotoxicity and accumulation of BPS to Pistia stratiotes under the influence of microplastics

Bisphenol S (BPS) is a contaminant of emerging concern, its exposure and phytotoxicity towards plants, however, is scarce. This study aimed at revealing the BPS translocation in plants and phytotoxicity in the presence of Polystyrene (PS) microplastics. Results found that BPS and PS showed no effect on plant growth, indicating the tolerance of plants towards BPS and PS co-contamination. In addition, plants enriched BPS from soil, and a major part of absorbed BPS was accumulated in roots, as supported by the higher BCF value in roots compared with leaves. Besides, the low TF (<1) suggested the capacity of plants to accumulate BPS in roots, and less translocation to leaves. PS negatively affected the translocation of BPS in plants. PS with large size (5 μm) also increased the distribution of BPS in organelles. Exposure risk assessment suggested low concern of BPS carried in plants to human health. This study underlines the bioaccumulation of BPS in plants, and the effects of PS in the translocation process.

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.

The adsorption mechanisms of oriental plane tree biochar toward bisphenol S: A combined thermodynamic evidence, spectroscopic analysis and theoretical calculations

Garden pruning waste is becoming a problem that intensifies the garbage siege. It is of great significance to purify polluted water using biochar prepared from garden pruning waste. Herein, the interaction mechanism between BPS and oriental plane tree biochar (TBC) with different surface functional groups was investigated by adsorption experiments, spectroscopic analysis and theoretical calculations. Adsorption kinetics and isotherm of BPS on TBC can be satisfactorily fitted into pseudo-second-order kinetic and Langmuir models, respectively. A rapid adsorption kinetic toward BPS was achieved by TBC in 15 min. As compared with TBC prepared at low temperature (300 °C) (LTBC), the maximum adsorption capacity of TBC prepared at high temperature (600 °C) (HTBC) can be significantly improved from 46.7 mg g^-1 to 72.9 mg g^-1. Besides, the microstructure and surface functional groups of HTBC were characterized using SEM, BET-N_2, and XPS analysis. According to density functional theory (DFT) theoretical calculations, the higher adsorption energy of HTBC for BPS was mainly attributed to π-π interaction rather than hydrogen bonding, which was further supported by the analysis of FTIR and Raman spectra as well as the adsorption thermodynamic parameters. These findings suggested that by improving π-π interaction through high pyrolysis temperature, BPS could be removed and adsorbed by biochar with high efficacy, cost-efficiency, easy availability, and carbon-negative in nature, contributing to global carbon neutrality.

Applications and influencing factors of the biochar-persulfate based advanced oxidation processes for the remediation of groundwater and soil contaminated with organic compounds

Biochar (BC) is a low-cost material rich in carbon, which is being used increasingly as a catalyst in persulfate-based advanced oxidation processes (PS-AOPs) for the remediation of groundwater and soil contaminated with organic compounds. In this work, a general summary of preparation methods and applications of various BC (i.e., pristine BC, magnetic BC, and chemically modified BC) in PS-AOPs is presented. Different influence factors (e.g., pH, anions, natural organic matter) for the degradation of organic compounds are discussed. Meanwhile, the influence of external energy (e.g., solar irradiation, UV-Vis, ultrasonic) is also mentioned. Furthermore, the advantage of different BC in PS-AOPs are compared. Finally, potential problems, challenges, and prospects in the application of biochar-persulfate based advanced oxidation processes (BCPS-AOPs) are discussed in the conclusion and perspective.

Repeated introduction of micropollutants enhances microbial succession despite stable degradation patterns

The increasing-volume release of micropollutants into natural surface waters has raised great concern due to their environmental accumulation. Persisting micropollutants can impact multiple generations of organisms, but their microbially-mediated degradation and their influence on community assembly remain understudied. Here, freshwater microbes were treated with several common micropollutants, alone or in combination, and then transferred every 5 days to fresh medium containing the same micropollutants to mimic the repeated exposure of microbes. Metabarcoding of 16S rRNA gene makers was chosen to study the succession of bacterial assemblages following micropollutant exposure. The removal rates of micropollutants were then measured to assess degradation capacity of the associated communities. The degradation of micropollutants did not accelerate over time but altered the microbial community composition. Community assembly was dominated by stochastic processes during early exposure, via random community changes and emergence of seedbanks, and deterministic processes later in the exposure, via advanced community succession. Early exposure stages were characterized by the presence of sensitive microorganisms such as Actinobacteria and Planctomycetes, which were then replaced by more tolerant bacteria such as Bacteroidetes and Gammaproteobacteria. Our findings have important implication for ecological feedback between microbe-micropollutants under anthropogenic climate change scenarios.

Intergenerational toxic effects of parental exposure to bisphenol AF on offspring and epigenetic modulations in zebrafish

Bisphenol AF (BPAF), an endocrine-disrupting chemical, has been detected in various environmental media because of its wide industrial applications. Meanwhile, substances that are known to be toxic to the reproductive system have been observed to interfere with the development of the offspring following parental exposure. This study was aimed at determining the gender-dependent intergenerational effects of BPAF on offspring development following either paternal or maternal exposure of adult zebrafish to an environmental concentration of BPAF. Four-month-old zebrafish (F0) were exposed to 10 μg/L of BPAF for 28 days, the developmental endpoints of F1 embryos were then tested without further treatment with BPAF. The results show that paternal BPAF exposure decreased the hatching rate, increased mortality, and shortened the body lengths of F1 larval offspring. In addition, it changed DNA and m⁶A RNA methylation gene expression levels in F0 testes and F1 larvae. Although maternal exposure increased mortality and enhanced antioxidant enzyme activities in F1 larvae, only DNA methylation gene expression was altered in F0 ovaries and F1 larvae. In addition, a short term BPAF exposure of zebrafish embryos from 4 h post-fertilization (hpf) until 120 hpf similarly impaired the early development of the larvae but only at a level relatively higher than 10 μg/L; and DNA and RNA methylation gene expression was regulated to some extent in BPAF exposure groups. Overall, our results indicate the gender-specific effects of BPAF on offspring development and epigenetic modulations, suggesting a relatively high susceptibility within the exposure window during gametogenesis and early embryonic developmental stages to environmental chemicals.

Green Synthesis of ZnO/BC Nanohybrid for Fast and Sensitive Detection of Bisphenol A in Water

A nanohybrid of zinc oxide and biochar (ZnO/BC) with high conductivity was green synthesized using a simple hydrothermal method, and utilized for the sensitive detection of bisphenol A (BPA) by coating the nanohybrid film on an electrode of glassy carbon. The ZnO/BC presented greatly improved electrocatalytic performance and electron transfer ability compared to the zinc oxide and biochar. The ZnO/BC film-coated electrode could detect the BPA in aqueous solution within 3 min while neglected interference from higher concentrations of regularly existing ions and similar concentrations of estradiol (E2), phenol, dichlorophenol (DCP), and ethinylestradiol (EE2). Under optimal conditions, the linear range of BPA detection was 5 × 10−7~1 × 10−4 mol/L, with a detection limit of 1 × 10−7 mol/L, and the detection sensitivity was 92 mA/M. In addition, the ZnO/BC electrode could detect BPA in a real water sample with good signal recovery. This electrode, with the advantages of an easy preparation, low cost, and fast response time, could be potentially applicable for environmental monitoring.

Elucidating the biodegradation pathway and catabolic genes of benzophenone-3 in Rhodococcus sp. S2-17

A new bacterium, Rhodococcus sp. S2-17, which could completely degrade an emerging organic pollutant, benzophenone-3 (BP-3), was isolated from contaminated sediment through an enrichment procedure, and its BP-3 catabolic pathway and genes were identified through metabolic intermediate and transcriptomic analyses and biochemical and genetic studies. Metabolic intermediate analysis suggested that strain S2-17 may degrade BP-3 using a catabolic pathway progressing via the intermediates BP-1, 2,4,5-trihydroxy-benzophenone, 3-hydroxy-4-benzoyl-2,4-hexadienedioic acid, 4-benzoyl-3-oxoadipic acid, 3-oxoadipic acid, and benzoic acid. A putative BP-3 catabolic gene cluster including cytochrome P450, flavin-dependent oxidoreductase, hydroxyquinol 1,2-dioxygenase, maleylacetate reductase, and α/β hydrolase genes was identified through genomic and transcriptomic analyses. Genes encoding the cytochrome P450 complex that demethylates BP-3 to BP-1 were functionally verified through protein expression, and the functions of the other genes were also verified through knockout mutant construction and intermediate analysis. This study suggested that strain S2-17 might have acquired the ability to catabolize BP-3 by recruiting the cytochrome P450 complex and α/β hydrolase, which hydrolyzes 4-benzoyl-3-oxoadipic acid to benzoic acid and 3-oxoadipic acid, genes, providing insights into the recruitment of genes of for the catabolism of emerging organic pollutants.

A critical review of presence, removal and potential impacts of endocrine disruptors bisphenol A

Bisphenol A (BPA) is a synthetic organic compound that is mainly used in the production of polymer materials polycarbonate and epoxy resin. Widespread use and irregular processing methods have led to BPA being detected globally, raising concerns about its environmental and health effects. This review outlines an overview of the presence and removal of BPA in the environment and consumer products. We also summarized the endocrine-disrupting toxicity of BPA, and the relatively less summarized neurotoxicity, cytotoxicity, reproductive toxicity, genotoxicity, and carcinogenicity. Human exposure data show that humans have been exposed to low concentrations of BPA for a long time, future research should focus on the long-term exposure and the migration of BPA from consumer products to humans and the possible health risks associated with human exposure to BPA. Exploring economical and effective methods to reduce and remove BPA from the environment is imperative. The development of safe, functional and reproducible BPA analogs and the study of its degradation products can be the focus of subsequent research.

Environmental occurrence and remediation of emerging organohalides: A review

As replacements for "old" organohalides, such as polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs), "new" organohalides have been developed, including decabromodiphenyl ethane (DBDPE), short-chain chlorinated paraffins (SCCPs), and perfluorobutyrate (PFBA). In the past decade, these emerging organohalides (EOHs) have been extensively produced as industrial and consumer products, resulting in their widespread environmental distribution. This review comprehensively summarizes the environmental occurrence and remediation methods for typical EOHs. Based on the data collected from 2015 to 2021, these EOHs are widespread in both abiotic (e.g., dust, air, soil, sediment, and water) and biotic (e.g., bird, fish, and human serum) matrices. A significant positive correlation was found between the estimated annual production amounts of EOHs and their environmental contamination levels, suggesting the prohibition of both production and usage of EOHs as a critical pollution-source control strategy. The strengths and weaknesses, as well as the future prospects of up-to-date remediation techniques, such as photodegradation, chemical oxidation, and biodegradation, are critically discussed. Of these remediation techniques, microbial reductive dehalogenation represents a promising in situ remediation method for removal of EOHs, such as perfluoroalkyl and polyfluoroalkyl substances (PFASs) and halogenated flame retardants (HFRs).

Bisphenol A-A Dangerous Pollutant Distorting the Biological Properties of Soil

Bisphenol A (BPA), with its wide array of products and applications, is currently one of the most commonly produced chemicals in the world. A narrow pool of data on BPA–microorganism–plant interaction mechanisms has stimulated the following research, the aim of which has been to determine the response of the soil microbiome and crop plants, as well as the activity of soil enzymes exposed to BPA pressure. A range of disturbances was assessed, based on the activity of seven soil enzymes, an abundance of five groups of microorganisms, and the structural diversity of the soil microbiome. The condition of the soil was verified by determining the values of the indices: colony development (CD), ecophysiological diversity (EP), the Shannon–Weaver index, and the Simpson index, tolerance of soil enzymes, microorganisms and plants (TI_BPA), biochemical soil fertility (BA₂₁), the ratio of the mass of aerial parts to the mass of plant roots (PR), and the leaf greenness index: Soil and Plant Analysis Development (SPAD). The data brought into sharp focus the adverse effects of BPA on the abundance and ecophysiological diversity of fungi. A change in the structural composition of bacteria was noted. Bisphenol A had a more beneficial effect on the Proteobacteria than on bacteria from the phyla Actinobacteria or Bacteroidetes. The microbiome of the soil exposed to BPA was numerously represented by bacteria from the genus Sphingomonas. In this object pool, the highest fungal OTU richness was achieved by the genus Penicillium, a representative of the phylum Ascomycota. A dose of 1000 mg BPA kg⁻¹ d.m. of soil depressed the activity of dehydrogenases, urease, acid phosphatase and β-glucosidase, while increasing that of alkaline phosphatase and arylsulfatase. Spring oilseed rape and maize responded significantly negatively to the soil contamination with BPA.

Mass Spectrometry Imaging of Low-Molecular-Weight Phenols Liberated from Plastics

The abundant and heterogeneous distribution of toxic phenol from plastics has drawn worldwide attention. However, the common analysis methods failed to identify the accurate species of these phenolic hazards from plastics in a direct and nondestructive approach. Herein, we demonstrate the layered double hydroxides (LDHs) as a novel matrix in matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) for low-molecular-weight phenols leaked from plastics. LDHs own abundant hydroxyl groups to facilitate chemoselectivity and ionization of phenols through the formation of hydrogen bonds with these phenols. More importantly, the LDH matrix could provide a distinguishable signal for the homolog and isomeride of these phenolic hazards. The developed method could realize nondestructive and in situ mapping of phenolic hazards in plastics. Our success could help to track the low-molecular-weight compounds liberated from plastics and supply spatial information for polluted plastics. We anticipated that the proposed approach could provide sufficient information to evaluate and alarm the safety of food packaging plastics.

Bisphenols exert detrimental effects on neuronal signaling in mature vertebrate brains

Bisphenols are important plasticizers currently in use and are released at rates of hundreds of tons each year into the biosphere^1–3. However, for any bisphenol it is completely unknown if and how it affects the intact adult brain^4–6, whose powerful homeostatic mechanisms could potentially compensate any effects bisphenols might have on isolated neurons. Here we analyzed the effects of one month of exposition to BPA or BPS on an identified neuron in the vertebrate brain, using intracellular in vivo recordings in the uniquely suited Mauthner neuron in goldfish. Our findings demonstrate an alarming and uncompensated in vivo impact of both BPA and BPS—at environmentally relevant concentrations—on essential communication functions of neurons in mature vertebrate brains and call for the rapid development of alternative plasticizers. The speed and resolution of the assay we present here could thereby be instrumental to accelerate the early testing phase of next-generation plasticizers.

Elisabeth Schirmer, Stefan Schuster and Peter Machnik investigated the effects of bisphenols A and S on neuronal functioning. Using in vivo recordings in goldfish they demonstrate that basic neuronal properties such as action potentials and synaptic transmission are perturbed after chronic exposure to bisphenols.

Persistence of three bisphenols and other trace organics of concern in anaerobic sludge under methanogenic conditions

The degradation and distribution of bisphenol A (BPA), bisphenol S (BPS) and bisphenol AF (BPAF) were evaluated in dilute anaerobic sludge slurries amended with a single bisphenol or a mixture of all three and maintained under methanogenic conditions over a 28-d period. No significant degradation of the bisphenols was observed in methane-generating microcosms. Rapid sorption to sludge particles was the primary removal process with sorption observed: BPAF > BPA > BPS. Several other trace organic chemicals of concern in the sludge were detected using quadrupole time of flight mass spectrometry. Of those detected, triclosan and triclocarban had sufficiently high intensities to quantify changes over the 28-d period in the bisphenol-amended microcosms. Similar to the bisphenols, triclosan and triclocarban concentrations also did not significantly change over the 28-d period with concentrations quantified at 2021 ± 627 and 1864 ± 769 μg/kg dry weight, respectively. Findings exemplify that methane-generating microcosms do not appear conducive to significant degradation of trace organics of concern in anaerobic sludge digesters.

Aerobic degradation of nonhalogenated organophosphate flame esters (OPEs) by enriched cultures from sludge: Kinetics, pathways, bacterial community evolution, and toxicity evaluation

The degradation by bacteria has been considered the main process for eliminating nonhalogenated organophosphate esters (OPEs) from wastewater treatment plants (WWTPs), but limited research has reported the biodegradation processes and clarified the microbial-mediated mechanisms for nonhalogenated OPE degradation in WWTPs. The aim of this study was to monitor the biodegradation of the most common nonhalogenated OPEs, namely, tris(2-butoxyethyl) phosphate (TBOEP), tris (n-butyl) phosphate (TNBP) and trisphenyl phosphate (TPHP), under aerobic conditions by sludge cultures from a conventional sewage plant. The microbial cultures were enriched separately with each OPE from activated sludge cultures, and the presence of glucose significantly enhanced degradation of the OPEs during the enrichment. The removal ratios for the three OPEs reached 29.3-89.9% after 5 cycles (25 days) of cultivation, and the first-order degradation kinetics followed the order of TPHP > TBOEP > TNBP, with their half-lives ranging between 12.8 and 99.0 h. Pathways of hydrolysis, hydroxylation, methoxylation, and substitution were confirmed for the aerobic biodegradation of these nonhalogenated OPEs, but only di-alkyl phosphates (DAPs) largely accumulated in culture medium as the most predominant transformation products. Phylotypes in Klebsiella were significantly more abundant during OPE biodegradation than in the initial sludge, which indicated that these microorganisms are associated with the biodegradation of nonhalogenated OPEs in sludge culture. Biodegradation of all investigated nonhalogenated OPEs was associated with a significant reduction in the residual toxicity to Vibrio fischeri, indicating a rather positive ecotoxicological outcome of the aerobic biotransformation processes achieved by the enriched sludge culture.

Kinetics and biotransformation products of bisphenol F and S during aerobic degradation with activated sludge

Bisphenol F (BPF) and bisphenol S (BPS) are becoming widespread in the environment despite the lack of information regarding their fate during wastewater treatment and in the environment. This study assessed the biodegradation kinetics of BPF and BPS during biological wastewater treatment with activated sludge using GC-MS/MS, and the identification of biotransformation products (BTPs) using LC-QTOF-MS. The results showed that BPF and BPS degrade readily and unlikely accumulate in biosolids or wastewater effluent (c_i = 0.1 mg L^-1, half-lives <4.3 days). The first-order kinetic model revealed that BPF (k_t = 0.20-0.38) degraded faster than BPS (k_t = 0.04-0.16) and that degradation rate decreases with an increasing initial concentration of BPS (half-lives 17.3 days). The absence of any additional organic carbon source significantly slowed down degradation, in particular, that of BPS (lag phase on day 18 instead of day 7). The machine-learning algorithm adopted as part of the non-targeted workflow identified three known BTPs and one novel BTP of BPF, and one known and ten new BTPs of BPS. The data from this study support possible new biodegradation pathways, namely sulphation, methylation, cleavage and the coupling of smaller bisphenol moieties.

Bioelectrochemically enhanced degradation of bisphenol S: mechanistic insights from stable isotope-assisted investigations

Electroactive microbes is the driving force for the bioelectrochemical degradation of organic pollutants, but the underlying microbial interactions between electrogenesis and pollutant degradation have not been clearly identified. Here, we combined stable isotope-assisted metabolomics (SIAM) and 13C-DNA stable isotope probing (DNA-SIP) to investigate bisphenol S (BPS) enhanced degradation by electroactive mixed-culture biofilms (EABs). Using SIAM, six 13C fully labeled transformation products were detected originating via hydrolysis, oxidation, alkylation, or aromatic ring-cleavage reactions from 13C-BPS, suggesting hydrolysis and oxidation as the initial and key degradation pathways for the electrochemical degradation process. The DNA-SIP results further displayed high 13C-DNA accumulation in the genera Bacteroides and Cetobacterium from the EABs and indicated their ability in the assimilation of BPS or its metabolites. Collectively, network analysis showed that the collaboration between electroactive microbes and BPS assimilators played pivotal roles the improvement in bioelectrochemically enhanced BPS degradation.

Efficient degradation of bisphenol A in water by heterogeneous activation of peroxymonosulfate using highly active cobalt ferrite nanoparticles

Cobalt ferrite CoFe₂O₄ catalyst was fabricated and systematically investigated as an efficient peroxymonosulfate (PMS, HSO₅^-) activator for the degradation of recalcitrant organic contaminants (ROCs) in water treatment. Both SO₄^- and OH on the surface of catalyst were unveiled to be primarily responsible for bisphenol A (BPA) degradation by a comprehensive study using electron paramagnetic resonance (EPR), radical scavengers and quantification of SO₄^-, and the negligible contribution of singlet oxygen (¹O₂) was also observed. BPA degradation was accelerated in the presence of humic acid, and it increased first but then decreased with the further addition of fulvic acid. Moreover, the presence of chloride and bicarbonate ions can enhance both BPA and TOC removal. The toxicity of the target aqueous solution ascended slowly at the early stage but then declined dramatically and almost vanished as the reaction proceeded. The removal efficiencies of other typical ROCs (clofibric acid, 2,4-dichlorophenol, etc.) and the decontamination of natural surface water spiked with BPA were also evaluated. This CoFe₂O₄/PMS process could be well applied as a safe, efficient, and sustainable approach for ROCs remediation in complex wastewater matrix.

Cobalt-based ZIF coordinated hybrids with defective TiO2-x for boosting visible light-driven photo-Fenton-like degradation of bisphenol A

Designing heterostructure of photocatalyst as an efficient approach to boost visible light-driven photocatalytic degradation, we prepared a series of cobalt-based ZIF coordinated with defective TiO_2-x, denoted as B-TiO_2-x@ZIF-67 composites, through wrapping defective B-TiO_2-x on ZIF-67 for promoting photocatalytic degradation efficiency of biphenyl A. The B-TiO_2-x@ZIF-67 composites displayed superior photocatalytic performance to pure TiO_2-x or ZIF-67 because of faster separation of photogenerated charge carriers and more suitable redox potentials. Such a novel photo-Fenton-like system composed of B-TiO_2-x@ZIF-67/H₂O₂/visible light accelerated the peroxidative degradation of biphenyl An up to a removal efficiency of 95.30%, which is also higher than that of photocatalysis or Fenton-like reaction alone. In addition, the degradation efficiency of biphenyl A is unchanged after catalyst reuse of four cycles. Integrating the trapping experiments and electrochemical analysis, we found the oxygen vacancy on B-TiO_2-x capturing the electrons to promote the separation of photogenerated charges, meanwhile the Co(II) in the composite decomposed hydrogen peroxide (H₂O₂) to produce more •OH radical. Both of them mutually boosted the removal efficiency. Finally, feasible degradation pathways of biphenyl A were proposed based on the assay of LC-MS spectrometry. This strategy offers a novel insight into fabrication of Co-ZIF-based TiO_2-x materials and application to visible light-driven photocatalytic and Fenton-like degradation reaction.

Fate of bisphenol S (BPS) and characterization of non-extractable residues in soil: Insights into persistence of BPS

The environmental fate and persistence of bisphenol S (BPS), a substitute for bisphenol A (BPA), are unclear. This study used ¹⁴C-labeled BPS to examine the fate, biodegradation, and residue properties of BPS incubated in an oxic soil for 28 days. BPS dissipated quickly, with a half-life of 2.8 days. Most of the BPS was mineralized (53.6 ± 0.2% of initial amount by day 28) or transformed into non-extractable residues (NERs) (45.1 ± 0.3%), with generation of minor extractable residues (3.7 ± 0.2%) containing two metabolites. NERs were formed mainly via physico-chemical entrapment (51.1 ± 2.4% of the total NERs, consisting almost exclusively of BPS) and ester-linkages (31.5 ± 3.0% of the total NERs, consisting of both BPS and polar metabolites). When mixed with fresh soil, BPS-derived NERs became unstable and bioavailable. Subsequent mineralization was determined for 19.5 ± 1.1% of the total NERs and 35.5 ± 2.6% of the physico-chemically entrapped BPS. A fate model was used to describe the kinetics of NER formation, which indicated that microbial activity in soil could have strongly reduced the kinetic rate of the release of physico-chemically entrapped NERs into free form and therefore increased the stability of this type of NERs in soil. Our results provide unique insights into the fate of BPS in soil and suggest that while BPS is biodegradable, it includes the formation of large amounts of reversibly physico-chemically entrapped and covalently bound ester-linked NERs. The instability of these NERs should be considered in assessments on environmental persistence and risks of BPS. Our study also points out the environmental importance of NERs of agrochemicals.

UV365 induced elimination of contaminants of emerging concern in the presence of residual nitrite: Roles of reactive nitrogen species

The presence of nitrite (NO₂^-) is inevitable with concentrations of several mg L^-1 in some typical water bodies. In this study, UV at wavelength of 365 nm was investigated to degrade contaminants of emerging concern (CECs) in the presence of NO₂^- at environmentally relevant concentrations (0.1-5.0 mg L^-1). Six selected CECs with different structures were efficiently removed because of the generation of reactive nitrogen species (RNS) and hydroxyl radical (HO^•) from photolysis of NO₂^-. Contributions of UV₃₆₅ photolysis, RNS, and HO^• to CEC degradation in UV₃₆₅/NO₂^- system were calculated, and RNS were found to be the predominant species that are responsible for CEC degradation. The second major contributor is HO^• for the degradation of selected CECs except for the case of sulfadiazine. Impacts of water matrix components (including dissolved oxygen, solution pH, and natural organic matter) on CEC degradation in UV₃₆₅/NO₂^- system were evaluated. Furthermore, evolution profiles of CECs and NO₂^- in UV₃₆₅/NO₂^- system were tracked when actual water samples were used as background, and a simultaneous removal of CECs and NO₂^- was observed. Transformation products of bisphenol A and carbamazepine were proposed according to the results of HPLC/MS and quantum chemistry calculations. Nitration induced by RNS and hydroxylation induced by HO^• are main reactions occurred during CEC degradation in UV₃₆₅/NO₂^- system. Overall, UV₃₆₅ is a potential technology to remove CECs and NO₂^- in aquatic environment when residual NO₂^- is present. Our present study also provides possibility for the application of sunlight to remediate water co-polluted by CECs and NO₂^-.

Assessment of solar-assisted electrooxidation of bisphenol AF and bisphenol A on boron-doped diamond electrodes

Bisphenol (BP) analogues in wastewater effluent and groundwater pose a potential threat to human health due to their ability to disrupt steroidogenesis. A new solar-assisted electrochemical process (SECP) was developed and evaluated for the degradation of BP analogues. The effects of quenchers, current density, initial pH, supporting electrolyte, and aqueous matrix on the removal kinetics of bisphenol AF (BPAF) and bisphenol A (BPA) were investigated. The kinetic constants of BPAF, BPA, and bisphenol S (BPS) in the SECP with irradiation intensity of 500 mW cm^-2 were 0.017 ± 0.002 min^-1, 0.022 ± 0.002 min^-1, and 0.012 ± 0.001 min^-1, respectively. The changes in the degradation rates of BPAF, BPA, and BPS in the presence of quenchers indicated the relative contribution of hydroxyl radical (^●OH) oxidation, anodic electrolysis, and singlet (¹O₂) oxygenation in the degradation of BPs in the SECP. The enhanced rate of generation of ^●OH and ¹O₂ was observed in the SECP compared with those in the conventional electrochemical system. The identification of the transformation products (TPs) of BPAF demonstrated that hydroxylation, ring cleavage, β-scission, and defluorination were the major processes during the oxidation in the SECP. The conversion to fluoride ions (76%) and mineralization of total organic carbon (72%) in the SECP indicated further degradation of TPs. The results from this study improved our understanding of the degradation of BP analogues in the electrooxidation irradiated by solar light and help to establish the application potential of the SECP for the effective degradation of emerging contaminants in wastewater.

Biodegradation of bisphenol compounds in the surface water of Taihu Lake and the effect of humic acids

Bisphenol analogues (BPs) pollution in the aquatic environment is increasingly a worldwide concern. There is an urgent need to understand the fate of BPs in the aquatic environment. In this study, we studied the biodegradation of eight BPs in Taihu Lake and discussed the effect of humic acid (HA), which was extracted from Taihu Lake sediment, on the disappearance of BPs. Under aerobic conditions, bisphenol AF (BPAF) and bisphenol S (BPS) were recalcitrant to biodegradation in the lake water. The half-lives for bisphenol F (BPF), bisphenol A (BPA), bisphenol B (BPB), bisphenol E (BPE), bisphenol Z (BPZ), and bisphenol M (BPM) ranged from 34 to 75 days in the Taihu Lake water collected in October 2018 and 12-72 days in that collected in May 2019. The biodegradation of BPs in summer was significantly higher than that in autumn. The presence of HA promoted the disappearance of BPs from Taihu Lake water by adsorbing and binding BPs. The disappearance rate of BPs accelerated with increasing concentrations of HA. However, the presence of HA decreased the biodegradation of BPs. When the concentration of HA was 10 mg/L, the single-adsorption capacities for BPS, BPA, BPB, BPM and BPAF were 3.18-10.33 mg/g in the Taihu Lake water with little desorption. BP adsorption and desorption in the BP mixtures were different from that in the single BPs. Competitive desorption occurred among the mixtures. The results of this study are the first to indicate the biodegradation of eight BPs in natural lake water and the possible effect of HA on the fate of BPs in the environment.

Strong impact of micropollutants on prokaryotic communities at the horizontal but not vertical scales in a subtropical reservoir, China

Micropollutants have become of great concern, because of their disrupting effects on the structure and function of microbial communities. However, little is known about the relative importance of trace micropollutants on the aquatic prokaryotic communities as compared to the traditional physico-chemical characteristics, especially at different spatial dimensions. Here, we investigated free-living (FL) and particle-associated (PA) prokaryotic communities in a subtropical water reservoir, China, across seasons at horizontal (surface water) and vertical (depth-profile) scales by using 16S rRNA gene amplicon sequencing. Our results showed that the shared variances of physico-chemicals and micropollutants explained majority of the spatial variations in prokaryotic communities, suggesting a strong joint effect of the two abiotic categories on reservoir prokaryotic communities. Micropollutants appeared to exert strong independent influence on the core sub-communities (i.e., abundant and wide-spread taxa) than on the satellite (i.e., less abundant and narrow-range taxa) counterparts. The pure effect of micropollutants on both core and satellite sub-communities from FL and PA fractions was ~1.5 folds greater than that of physico-chemical factors at the horizontal scale, whereas an opposite effect was observed at the vertical scale. Moreover, eight micropollutants including anti-fungal agents, antibiotics, bisphenol analogues, stimulant and UV-filter were identified as the major disrupting compounds with strong associations with core taxa of typical freshwater prokaryotes. Altogether, we concluded that the ecological disrupting effects of micropollutants on prokaryotic communities may vary along horizontal and vertical dimensions in freshwater ecosystems.

Crucial roles of oxygen and superoxide radical in bisulfite-activated persulfate oxidation of bisphenol AF: Mechanisms, kinetics and DFT studies

Though natural reducing agents have been demonstrated as desirable catalysts for environmental remediation, the mechanism of catalytic activation of persulfate (PS) by bisulfite (S(IV)) remains unclear. In this study, an emerging contaminant bisphenol AF (BPAF) was employed as the target compound to examine the activation and degradation mechanism in PS/S(IV) system. Sulfate radical (SO₄•-) was evidenced as the dominant radical accounting for BPAF degradation via quantitative analysis, while hydroxyl radical (•OH) and singlet oxygen (¹O₂) were minor contributors. Superoxide radical (O₂•-) was identified as an intermediate radical in promoting BPAF removal through quenching experiments and electron paramagnetic resonance analysis. Tests in oxygen-rich and oxygen-deficient systems were conducted and the results were contrasted to elucidate the important role of oxygen in BPAF degradation and SO₄•--formation. In addition, the effect of Dissolved Oxygen (DO) was simulated using two separate kinetic models. Decomposition mechanism of BPAF was afterwards clarified via the density-functional theory calculations using Fukui index to predict the vulnerable sites and the intermediate products. This study provides a mechanistic understanding of the activation of PS/S(IV) system on the BPAF removal, especially the critical role of DO and O₂•- in SO₄•- generation.

Prenatal exposure to bisphenol A and its alternatives and child neurodevelopment at 2 years

While increasing evidence has shown that prenatal bisphenol A (BPA) exposure is adversely associated with child neurodevelopment, little is known about the neurodevelopmental effects of BPA alternatives, such as bisphenol S (BPS) and bisphenol F (BPF). We aimed to evaluate the relationships of repeated measurements of bisphenol exposure during pregnancy with child neurodevelopment. From 2014-2015, 456 mother-child pairs were included in the present study. Each had a spot urine sample in the first, second, and third trimester, respectively, during pregnancy for BPA, BPS, and BPF measurements. Children's neurodevelopment was assessed using the Bayley Scales of Infant Development at 2 years. In adjusted models, children's psychomotor development index scores decreased across quartiles of BPS concentrations [-5.52 (95 % CI: -10.06, -0.99) in the 4th quartile vs. 1 st quartile, P-trend = 0.01]. Each 10-fold increase in BPA concentrations was related to lower mental development index scores only in the second trimester [-2.87 (95 % CI: -4.98, -0.75), P_{trimester-int} = 0.04]. However, prenatal BPF exposure was not significantly associated with child neurodevelopment. We provide evidence that prenatal exposure to BPA and BPS may affect child neurodevelopment.