Graph neural networks-enhanced relation prediction for ecotoxicology (GRAPE).

Exposure to toxic chemicals threatens species and ecosystems. This study introduces a novel approach using Graph Neural Networks (GNNs) to integrate aquatic toxicity data, providing an alternative to complement traditional in vivo ecotoxicity testing. This study pioneers the application of GNN in ecotoxicology by formulating the problem as a relation prediction task. GRAPE's key innovation lies in simultaneously modelling 444 aquatic species and 2826 chemicals within a graph, leveraging relations from existing datasets where informative species and chemical features are augmented to make informed predictions. Extensive evaluations demonstrate the superiority of GRAPE over Logistic Regression (LR) and Multi-Layer Perceptron (MLP) models, achieving remarkable improvements of up to a 30% increase in recall values. GRAPE consistently outperforms LR and MLP in predicting novel chemicals and new species. In particular, GRAPE showcases substantial enhancements in recall values, with improvements of ≥ 100% for novel chemicals and up to 13% for new species. Specifically, GRAPE correctly predicts the effects of novel chemicals (104 out of 126) and effects on new species (7 out of 8). Moreover, the study highlights the effectiveness of the proposed chemical features and induced network topology through GNN for accurately predicting metallic (74 out of 86) and organic (612 out of 674) chemicals, showcasing the broad applicability and robustness of the GRAPE model in ecotoxicological investigations. The code/data are provided at https://github.com/csiro-robotics/GRAPE.

Proteogenomic characterization of difficult-to-treat breast cancer with tumor cells enriched through laser microdissection.

BACKGROUND: Breast cancer (BC) is the most commonly diagnosed cancer and the leading cause of cancer death among women globally. Despite advances, there is considerable variation in clinical outcomes for patients with non-luminal A tumors, classified as difficult-to-treat breast cancers (DTBC). This study aims to delineate the proteogenomic landscape of DTBC tumors compared to luminal A (LumA) tumors. METHODS: We retrospectively collected a total of 117 untreated primary breast tumor specimens, focusing on DTBC subtypes. Breast tumors were processed by laser microdissection (LMD) to enrich tumor cells. DNA, RNA, and protein were simultaneously extracted from each tumor preparation, followed by whole genome sequencing, paired-end RNA sequencing, global proteomics and phosphoproteomics. Differential feature analysis, pathway analysis and survival analysis were performed to better understand DTBC and investigate biomarkers. RESULTS: We observed distinct variations in gene mutations, structural variations, and chromosomal alterations between DTBC and LumA breast tumors. DTBC tumors predominantly had more mutations in TP53, PLXNB3, Zinc finger genes, and fewer mutations in SDC2, CDH1, PIK3CA, SVIL, and PTEN. Notably, Cytoband 1q21, which contains numerous cell proliferation-related genes, was significantly amplified in the DTBC tumors. LMD successfully minimized stromal components and increased RNA-protein concordance, as evidenced by stromal score comparisons and proteomic analysis. Distinct DTBC and LumA-enriched clusters were observed by proteomic and phosphoproteomic clustering analysis, some with survival differences. Phosphoproteomics identified two distinct phosphoproteomic profiles for high relapse-risk and low relapse-risk basal-like tumors, involving several genes known to be associated with breast cancer oncogenesis and progression, including KIAA1522, DCK, FOXO3, MYO9B, ARID1A, EPRS, ZC3HAV1, and RBM14. Lastly, an integrated pathway analysis of multi-omics data highlighted a robust enrichment of proliferation pathways in DTBC tumors. CONCLUSIONS: This study provides an integrated proteogenomic characterization of DTBC vs LumA with tumor cells enriched through laser microdissection. We identified many common features of DTBC tumors and the phosphopeptides that could serve as potential biomarkers for high/low relapse-risk basal-like BC and possibly guide treatment selections.

Polyethylene microplastics induced lipidomic responses in Chironomus tepperi: A two-generational exploration.

Microplastics (MPs) accumulating in freshwater sediment have raised concerns about potential risks to benthic dwelling organisms, yet few studies have examined the long-term impacts caused by MP exposure. This study investigated alterations to lipid profiles in an Australian freshwater invertebrate, Chironomus tepperi, induced by polyethylene MP fragments (1-45 µm) at environmentally relevant concentrations (125, 250, 500 and 1000 MPs/kg sediment), using a two-generational experimental design. In the parental generation, the relative abundance of triacylglycerols, total fatty acids and unsaturated fatty acids exhibited apparent hormetic patterns, with low-concentration stimulation and high-concentration inhibition observed. The overall trend in these lipid classes is consistent with previously observed changes to polar metabolite profiles, indicating that ingestion of MPs could inhibit nutrient assimilation from food leading to disruption of energy availability. In the first filial generation continuously exposed to MPs, however, abundance of cholesterol and total fatty acids increased with increasing exposure concentrations, suggesting different effects on energy metabolism between the parental generation and offspring. No differences in the lipidome were observed in first filial larvae that were not exposed, implying that MPs pose negligible carry-over effects. Overall, the combined results of this study together with a preceding metabolomics study provide evidence of a physical effect of MPs with subsequent impacts to bioenergetics. Nevertheless, future research is required to explore the potential long-term impacts caused by MPs, and to unravel the impacts of the surfactant control as a potential contributor to the observed hormetic response, particularly for studies exploring sub-lethal effects of MP exposure using sensitive omics techniques.

Role of Consolidation and Maintenance.

Consolidation therapy consists of short-term therapy after stem cell transplant in multiple myeloma. Key consolidation trials have shown mixed results on whether consolidation should be included after transplant, leading to varied clinical practice. Maintenance therapy consists of long-term, typically fixed-duration or indefinite, therapy. Standard-risk patients typically receive single-agent therapy, whereas high-risk may benefit from doublet therapy and beyond. Adverse events and quality of life concerns should be considered, as optimal duration of maintenance therapy continues to be studied.

Association of clinicopathologic and molecular factors with the occurrence of positive margins in breast cancer.

PURPOSE: To explore the association of clinicopathologic and molecular factors with the occurrence of positive margins after first surgery in breast cancer. METHODS: The clinical and RNA-Seq data for 951 (75 positive and 876 negative margins) primary breast cancer patients from The Cancer Genome Atlas (TCGA) were used. The role of each clinicopathologic factor for margin prediction and also their impact on survival were evaluated using logistic regression, Fisher's exact test, and Cox proportional hazards regression models. In addition, differential expression analysis on a matched dataset (71 positive and 71 negative margins) was performed using Deseq2 and LASSO regression. RESULTS: Association studies showed that higher stage, larger tumor size (T), positive lymph nodes (N), and presence of distant metastasis (M) significantly contributed (p ≤ 0.05) to positive surgical margins. In case of surgery, lumpectomy was significantly associated with positive margin compared to mastectomy. Moreover, PAM50 Luminal A subtype had higher chance of positive margin resection compared to Basal-like subtype. Survival models demonstrated that positive margin status along with higher stage, higher TNM, and negative hormone receptor status was significant for disease progression. We also found that margin status might be a surrogate of tumor stage. In addition, 29 genes that could be potential positive margin predictors and 8 pathways were identified from molecular data analysis. CONCLUSION: The occurrence of positive margins after surgery was associated with various clinical factors, similar to the findings reported in earlier studies. In addition, we found that the PAM50 intrinsic subtype Luminal A has more chance of obtaining positive margins compared to Basal type. As the first effort to pursue molecular understanding of the margin status, a gene panel of 29 genes including 17 protein-coding genes was also identified for potential prediction of the margin status which needs to be validated using a larger sample set.

Environmentally relevant concentrations of chemically complex shale gas wastewater led to reduced fitness of water fleas (Daphnia carinata): Multiple lines of evidence approach.

Shale gas hydraulic fracturing generates flowback waters that pose a threat to aquatic organisms if released into the environment. In order to prevent adverse effects on aquatic ecosystems, multiple lines of evidence are needed to guide better decisions and management actions. This study employed a multi-disciplinary approach, combining direct toxicity assessment (DTA) on the water flea Daphnia carinata and LC-MS metabolomics analysis to determine the impact of a major ion salinity control (SC) and a cumulative flowback shale gas wastewater (SGW) from a well in the Beetaloo Sub-basin, Northern Territory, Australia. The exposures included a culture water control, simply further referred to as 'control', SC at 1% and 2% (v/v) and SGW at 0.125, 0.25, 0.5, 1% and 2% (v/v). The results showed that reproduction was significantly increased at SGW 0.5%, and significantly decreased when exposed to SC 2%. SGW 2% was found to be acutely toxic for the D. carinata (< 48-h). Second generation (F1) of D. carinata exposed to 0.125-1% SGW generally saw reduced activity in four oxidative biomarkers: glutathione S-transferase, lipid peroxidation, reactive oxygen species, and superoxide dismutase. At the metabolomics level, we observed significant changes in 103 metabolites in Daphnia exposed to both SGW and elevated salinity, in comparison to the control group. These changes indicate a range of metabolic disturbances induced by SGW and salinity, such as lipid metabolism, amino acid metabolism, nucleotide synthesis, energy production, and the biosynthesis of crucial molecules like hormones and pigments. These multiple lines of evidence approach not only highlights the complexities of SGW's impact on aquatic ecosystems but also underscores the importance of informed decision-making and management practices to safeguard the environment and its inhabitants.

A review on versatile applications of biomaterial/polycationic chitosan: An insight into the structure-property relationship.

Chitosan is a versatile and generous biopolymer obtained by alkaline deacetylation of naturally occurring chitin, the second most abundant biopolymer after cellulose. The excellent physicochemical properties of polycationic chitosan are attributed to the presence of varied functional groups such as amino, hydroxyl, and acetamido groups enabling researchers to tailor the structure and properties of chitosan by different methods such as crosslinking, grafting, copolymerization, composites, and molecular imprinting techniques. The prepared derivatives have diverse applications in the food industry, water treatment, cosmetics, pharmaceuticals, agriculture, textiles, and biomedical applications. In this review, numerous applications of chitosan and its derivatives in various fields have been discussed in detail with an insight into their structure-property relationship. This review article concludes and explains the chitosan's biocompatibility and efficiency that has been done so far with future usage and applications as well. Moreover, the possible mechanism of chitosan's activity towards several emerging fields such as energy storage, biodegradable packaging, photocatalysis, biorefinery, and environmental bioremediation are also discussed. Overall, this comprehensive review discusses the science and complete information behind chitosan's wonder function to improve our understanding which is much needful as well as will pave the way towards a sustainable future.

Changes in lipids and inflammation in adults with super-refractory status epilepticus on a ketogenic diet.

Introduction: This study aims to test the hypothesis that increased ketone body production resulting from a ketogenic diet (KD) will correlate with reductions in pro-inflammatory cytokines and lipid subspecies and improved clinical outcomes in adults treated with an adjunctive ketogenic diet for super-refractory status epilepticus (SRSE). Methods: Adults (18 years or older) were treated with a 4:1 (fat: carbohydrate and protein) ratio of enteral KD as adjunctive therapy to pharmacologic seizure suppression in SRSE. Blood and urine samples and clinical measurements were collected at baseline (n = 10), after 1 week (n = 8), and after 2 weeks of KD (n = 5). In addition, urine acetoacetate, serum ß-hydroxybutyrate, lipidomics, pro-inflammatory cytokines (IL-1ß and IL-6), chemokines (CCL3, CCL4, and CXCL13), and clinical measurements were obtained at these three time points. Univariate and multivariate data analyses were performed to determine the correlation between ketone body production and circulating lipids, inflammatory biomarkers, and clinical outcomes. Results: Changes in lipids included an increase in ceramides, mono-hexosylceramide, sphingomyelin, phosphocholine, and phosphoserines, and there was a significant reduction in pro-inflammatory mediators, IL-6 and CXCL13, seen at 1 and 2 weeks of KD. Higher blood ß-hydroxybutyrate levels at baseline correlated with better clinical outcomes; however, ketone body production did not correlate with other variables during treatment. Higher chemokine CCL3 levels following treatment correlated with a longer stay in the intensive care unit and a higher modified Rankin Scale score (worse neurologic disability) at discharge and 6-month follow up. Discussion: Adults receiving an adjunctive enteral ketogenic diet for super-refractory status epilepticus exhibit alterations in select pro-inflammatory cytokines and lipid species that may predict their response to treatment.

Metabolomic responses in freshwater benthic invertebrate, Chironomus tepperi, exposed to polyethylene microplastics: A two-generational investigation.

The accumulation of microplastics (MPs) in sediments could pose risks to benthic organisms and their progeny. Here, we examined effects on traditional apical endpoints along with changes to whole body metabolite profiles induced by irregular shaped polyethylene MPs (1-45 µm) at environmentally relevant concentrations (125, 250, 500 and 1000 MPs/kg sediment) in Chironomus tepperi using a two-generation exposure regime. Survival and emergence of C. tepperi were negatively affected in the parental generation at the two highest concentrations, whereas endpoints associated with growth were only impacted at 1000 MPs/kg sediment. Metabolites associated with several amino acid and energy metabolism pathways were present at lower abundances at the highest exposure concentration suggesting an overall impact on bioenergetics which relates to the inhibition of food acquisition or nutrient assimilation caused by ingestion of MPs, rather than a traditional receptor-mediated toxicity response. In contrast, no significant effects on apical endpoints were observed in the continuous exposure of first filial generation, and lactic acid was the only metabolite that differed significantly between groups. Larvae in unexposed conditions showed no differences in survival or metabolite profiles suggesting that effects in the parental generation do not carry over to the next filial generation. The findings provide evidence on the underlying impacts of MP ingestion and potential adaption to MP exposure of C. tepperi.

Predictors of lenalidomide maintenance duration after autologous stem cell transplant in patients with multiple myeloma.

BACKGROUND: For patients with multiple myeloma (MM) who have undergone autologous stem cell transplant (auto-SCT), the immunomodulatory agent lenalidomide is a first-line option for maintenance therapy. Because longer durations of lenalidomide maintenance are associated with improved survival, identifying strategies to avoid premature cessation of maintenance is an important priority in the post-transplant setting. OBJECTIVES: The primary objective of this analysis was to identify specific clinical predictors of lenalidomide treatment duration that could guide optimal medication management. Key secondary objectives included predictors of intolerable toxicity, rationale for lenalidomide dose reduction/discontinuation, and characterization of dose adjustments. STUDY DESIGN: This retrospective, multi-center cohort study included adults with MM who underwent auto-SCT and initiated maintenance lenalidomide between 01/01/2012 and 02/28/2021. Variables assessed as potential predictors of maintenance duration or intolerable toxicity included age, body mass index (BMI), Eastern Cooperative Oncology Group (ECOG) performance status at time of auto-SCT, renal function, initial lenalidomide dose, use of combination maintenance therapy, and cytogenetic risk category. RESULTS: Among 299 patients included, the median age at time of auto-SCT was 62 years (range 30-77). The majority of patients had standard-risk cytogenetics (64%) and an ECOG performance status of 0 or 1 (72%). In the overall population, the median duration of maintenance was 1.3 years (range 0.3-8.6 years). The median initial dose of lenalidomide was 10 mg daily (range 2.5-25 mg). During the study period, 35% of patients had a dose reduction due to toxicity, 21% stopped lenalidomide due to disease progression, and 19% stopped due to toxicity. Multivariate linear regression analyses did not identify any significant predictors of lenalidomide duration or discontinuation due to intolerable toxicity. The most frequently reported toxicities leading to discontinuation were cytopenias, rash, and fatigue. CONCLUSION: This analysis did not identify any significant risk factors to predict the duration of lenalidomide maintenance or discontinuation for toxicity following auto-SCT in patients with MM. While limited by the retrospective design and relatively small sample size, our findings suggest that a priori lenalidomide dose reductions based on patient co-morbidities or performance status may not substantially affect the duration of lenalidomide maintenance.

Mixture Toxicity of Three Unconventional Gas Fracking Chemicals, Barium, O-Cresol, and Sodium Chloride, to the Freshwater Shrimp Paratya australiensis.

The 96-h acute toxicity of barium (Ba2+ ), o-cresol, and sodium chloride (NaCl) to Paratya australiensis was assessed in single, binary, and ternary combinations in addition to three biochemical assays: glutathione S-transferase, acetylcholinesterase, and sodium-potassium adenosine triphosphatase. The 96-h lethal concentrations that expressed 50% mortality (LC50) in the single-toxicant exposures were Ba2+ = 23.4 mg/L, o-cresol = 12.2 mg/L, and NaCl = 4198 mg/L. Mortality from o-cresol exposure occurred between 11 and 22 mg/L, whereas Ba2+ was more gradual across 10-105 mg/L, and most of the NaCl mortality occurred between 2050 and 4100 mg/L. Toxic units were used to assess the binary and ternary interactions of the toxicants. A more than additive effect was observed for most combinations in the binary chemical exposures, with the ternary combinations yielding highly synergistic interactions. Greater synergism was observed with the 96-h LC50 of o-cresol in combination with the three concentrations of NaCl (1025, 2050, and 3075 mg/L) compared with Ba2+ , with toxic units of 0.38, 0.48, and 0.10 (o-cresol) and 0.71, 0.67, and 0.50 (Ba2+ ). No notable enzyme activity trends were observed in the enzyme biomarker responses from both individual and mixture exposures. Although acute single-species toxicity tests tend to underestimate the effects of Ba2+ , o-cresol, and NaCl on populations, communities, and ecosystems in seminatural (e.g., mesocosms) and natural systems, there are currently no published acute toxicity data available for P. australiensis and the three toxicants used in the present study. The present study shows that chemicals with different toxicity mechanisms can potentially lead to more synergistic responses. Environ Toxicol Chem 2023;42:481-494. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Valorization of potato peel waste: Recovery of p-hydroxy benzoic acid (antioxidant) through molecularly imprinted solid-phase extraction.

Solid waste management of the potato peels, generated during the processing of potatoes, can be done sustainably by adding value to the peel waste. Peels contains polyphenols, which serve as a defense mechanism against foreign pathogens in plants and have a variety of pharmacological properties such as antioxidant and anti-carcinogenic properties. However, specific segregation of any one polyphenol from waste can be challenging due to its complex matrix and low concentration of the targeted polyphenol. This work presents a way to combat this challenge through molecularly imprinted solid-phase extraction (MISPE) using customized graphene oxide-based molecularly imprinted composite (GOMIP) as sorbent for the selective recovery of p-hydroxy benzoic acid (P-HA) (antioxidant used in food industries), from potato peels for the effective valorization of peels. Various parameters such as flow rate, vacuum manifold pressure, conditioning solvent, washing solvent, and elution solvent were optimized for effective segregation of targeted P-HA. The imprinting factor of 2.14, obtained using breakthrough curves for GOMIP and control (graphene oxide based non-imprinted composite-GONIP) sorbent under optimized condition, indicated the ability of the sorbent GOMIP to recover P-HA from the extract of potato peels. Reusability and selectivity studies were performed for GOMIP sorbent using the real sample [potato peels extract (PPE)]. 77.44% recovery for P-HA was exhibited by the GOMIP sorbent in the MISPE cartridge as determined using HPLC. MISPE with customized GOMIP sorbent can be a sustainable approach to valorize the potato peel solid waste.

Use of Human Lung Tissue Models for Screening of Drugs against SARS-CoV-2 Infection.

The repurposing of licenced drugs for use against COVID-19 is one of the most rapid ways to develop new and alternative therapeutic options to manage the ongoing pandemic. Given circa 7817 licenced compounds available from Compounds Australia that can be screened, this paper demonstrates the utility of commercially available ex vivo/3D airway and alveolar tissue models. These models are a closer representation of in vivo studies than in vitro models, but retain the benefits of rapid in vitro screening for drug efficacy. We demonstrate that several existing drugs appear to show anti-SARS-CoV-2 activity against both SARS-CoV-2 Delta and Omicron Variants of Concern in the airway model. In particular, fluvoxamine, as well as aprepitant, everolimus, and sirolimus, has virus reduction efficacy comparable to the current standard of care (remdesivir, molnupiravir, nirmatrelvir). Whilst these results are encouraging, further testing and efficacy studies are required before clinical use can be considered.

Systematic Down-Selection of Repurposed Drug Candidates for COVID-19.

SARS-CoV-2 is the cause of the COVID-19 pandemic which has claimed more than 6.5 million lives worldwide, devastating the economy and overwhelming healthcare systems globally. The development of new drug molecules and vaccines has played a critical role in managing the pandemic; however, new variants of concern still pose a significant threat as the current vaccines cannot prevent all infections. This situation calls for the collaboration of biomedical scientists and healthcare workers across the world. Repurposing approved drugs is an effective way of fast-tracking new treatments for recently emerged diseases. To this end, we have assembled and curated a database consisting of 7817 compounds from the Compounds Australia Open Drug collection. We developed a set of eight filters based on indicators of efficacy and safety that were applied sequentially to down-select drugs that showed promise for drug repurposing efforts against SARS-CoV-2. Considerable effort was made to evaluate approximately 14,000 assay data points for SARS-CoV-2 FDA/TGA-approved drugs and provide an average activity score for 3539 compounds. The filtering process identified 12 FDA-approved molecules with established safety profiles that have plausible mechanisms for treating COVID-19 disease. The methodology developed in our study provides a template for prioritising drug candidates that can be repurposed for the safe, efficacious, and cost-effective treatment of COVID-19, long COVID, or any other future disease. We present our database in an easy-to-use interactive interface (CoviRx that was also developed to enable the scientific community to access to the data of over 7000 potential drugs and to implement alternative prioritisation and down-selection strategies.

The Acute Toxicity of Salinity in Onshore Unconventional Gas Waters to Freshwater Invertebrates in Receiving Environments: A Systematic Review.

Industries such as unconventional natural gas have seen increased global expansion to meet the increasing energy needs of our increasing global population. Unconventional gas uses hydraulic fracturing that produces significant volumes of produced waters, which can be highly saline and pose a toxic threat to freshwater invertebrates if exposure via discharges, spills, leaks, or runoff were to occur. The primary aim of the present review was to determine the sodium (Na+ ) and chloride (Cl- ) content of these waters as an approximate measure of salinity and how these values compare to the NaCl or synthetic marine salt acute toxicity values of freshwater invertebrate taxa. Shale gas produced waters are much more saline with 78 900 ± 10 200 NaCl mg/L and total dissolved solids (TDS) of 83 200 ± 12 200 mg/L compared to coal bed methane (CBM) produced waters with 4300 ± 1100 NaCl mg/L and TDS of 5900 ± 1300 mg/L and pose a far greater toxicity risk from NaCl to freshwater invertebrates. In addition, the toxicity of other major ions (Ca2+ , K+ , Mg2+ , CO 3 2 - , HCO3 - , and SO 4 2 - ) and their influence on the toxicity of Na+ and Cl- were evaluated. Exposure of untreated and undiluted shale gas produced waters to freshwater invertebrates is likely to result in significant or complete mortality. Shale gas produced waters have higher concentrations of various metals compared with CBM produced waters and are more acidic. We recommend future research to increase the reporting and consistency of water quality parameters, metals, and particularly organics of produced waters to provide a better baseline and help in further investigations. Environ Toxicol Chem 2022;41:2928-2949. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

A review of omics-based PFAS exposure studies reveals common biochemical response pathways.

Per and Polyfluoroalkyl Substances (PFAS) are a diverse group of man-made chemicals with a range of industrial applications and which are widespread in the environment. They are structurally diverse but comprise a common chemical feature of at least one (though usually more) perfluorocarbon moiety (-CnF2n-) attached to a functional group such as a carboxylic or sulphonic acid. The strength of the Carbon-Fluorine bond means the compounds do not break down easily and can thus bioaccumulate. PFAS are of high concern to regulators and the public due to their potential toxicity and high persistence. At high exposure levels, PFAS have been implicated in a range of harmful effects on human and environmental health, particularly problems in/with development, cholesterol and endocrine disruption, immune system function, and oncogenesis. However, most environmental toxicology studies use far higher levels of PFAS than are generally found in the environment. Additionally, since the type of exposure, the PFAS used, and the organisms tested all vary between studies, so do the results. Traditional ecotoxicology studies may thus not identify PFAS effects at environmentally relevant exposures. Here we conduct a review of omics-based PFAS exposure studies using laboratory ecotoxicological methodologies and environmentally relevant exposure levels and show that common biochemical response pathways are identified in multiple studies. A major pathway identified was the pentose phosphate shunt pathway. Such molecular markers of sublethal PFAS exposure will greatly benefit accurate and effective risk assessments to ensure that new PFAS regulations can consider the full effects of PFAS exposure on environmental and human health receptors.

The influence of salinity on the chronic toxicity of shale gas flowback wastewater to freshwater organisms.

The potential environmental risk associated with flowback waters generated during hydraulic fracturing of target shale gas formations needs to be assessed to enable management decisions and actions that prevent adverse impacts on aquatic ecosystems. Using direct toxicity assessment (DTA), we determined that the shale gas flowback wastewater (FWW) from two exploration wells (Tanumbirini-1 and Kyalla 117 N2) in the Beetaloo Sub-basin, Northern Territory, Australia were chronically toxic to eight freshwater biota. Salinity in the respective FWWs contributed 16% and 55% of the chronic toxicity at the 50% effect level. The remaining toxicity was attributed to unidentified chemicals and interactive effects from the mixture of identified organics, inorganics and radionuclides. The most sensitive chronic endpoints were the snail (Physa acuta) embryo development (0.08-1.1% EC10), microalga (Chlorella sp. 12) growth rate inhibition (0.23-3.7% EC10) and water flea (Ceriodaphnia cf. dubia) reproduction (0.38-4.9% EC10). No effect and 10% effect concentrations from the DTA were used in a species sensitivity distribution to derive "safe" dilutions of 1 in 300 and 1 in 1140 for the two FWWs. These dilutions would provide site-specific long-term protection to 95% of aquatic biota in the unlikely event of an accidental spill or seepage.

ZrO2@chitosan composite for simultaneous photodegradation of three emerging contaminants and antibacterial application.

Emerging contaminants (ECs) are often detected in water bodies due to their prevalent use combined with inefficiency of the conventional wastewater treatment plants for their complete removal. Elimination of ECs using photocatalysis as a tertiary treatment can be a sustainable option for the reuse wastewater. Reported herewith is a photocatalyst, chitosan-based zirconia hybrid composite (ZrO2CTS-HC) for the individual/ simultaneous degradation of multiple ECs like Congo red (CR), Methyl orange (MO) and 4-hydroxybenzoic acid (4-HA) under visible light irradiation. Successfully synthesized ZrO2CTS-HC as confirmed by theoretical and various characterization techniques depicted photodegradation efficiency of 91.11, 69.11 and 78.40% for CR, MO and 4-HA respectively (SD 0.5-0.95; HPLC) aided by the reactive hydroxyl radical. Probable degradation mechanism supported by LC-MS/MS, COD and TOC along with reusability and antibacterial ability towards E.Coli & S.aureus is also reported. ZrO2CTS-HC can be a good option for elimination of residual ECs during tertiary treatment.

Antioxidant analysis of ultra-fast selectively recovered 4-hydroxy benzoic acid from fruits and vegetable peel waste using graphene oxide based molecularly imprinted composite.

Food processing industries generate 25-30% of fruit and vegetable peel (F&VP) waste of the total produce, which are rich in polyphenolic antioxidants (PA). Sustainable solution for the above waste can be its valorization for the recovery of PA, often used as natural preservative. Present work reports rationally designed graphene oxide-based molecularly imprinted composites (GOMIPs) using ionic liquid 1-allyl-3-octylimidazolium chloride (A) as a green functional monomer for selective recovery of PA 4-Hydroxy benzoic acid (4HA) from F&VP/pomegranate peel (PGP) waste. GOMIP-A and GOMIP-V were characterized using various techniques for its successful synthesis. GOMIP-A attained equilibrium within 10 min with adsorption capacity of 190.56 µmol g-1 for 4HA. Developed HPLC method depicted selective recovery of 77.23% and 62.83% 4HA from F&VP and PGP waste respectively by GOMIP-A. Subsequently, desorbed 4HA from GOMIP-A matrices exhibited the antioxidant potential of 33.53% (F&VP extract) and 47.97% (PGP extract) for DPPH radical.