Phthalic Acid Esters Research Articles

Association of joint exposure to organophosphorus flame retardants and phthalate acid esters with gestational diabetes mellitus: a nested case-control study

BackgroundOrganic phosphate flame retardants (OPFRs) and phthalate acid esters (PAEs) are common endocrine-disrupting chemicals that cause metabolic disorders. This study aimed to assess the association between joint exposure to OPFRs and PAEs during early pregnancy in women with gestational diabetes mellitus (GDM).MethodsSeven OPFRs and five PAEs were detected in the urine of 65 GDM patients and 100 controls using gas chromatography-tandem triple quadrupole mass spectrometry (GC-MS). The association of OPFRs and PAEs with GDM was assessed using logistic regression, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) models.ResultsLevels of dibutyl phthalate (DBP), di-2-ethylhexyl phthalate (DEHP), diethyl phthalate (DEP), dimethyl phthalate (DMP), tris (2-butoxyethyl) phosphate (TBEP), tributyl phosphate (TBP), tris (2-chloroethyl) phosphate (TCEP), tris (1,3-dichloro-2-propyl) phosphate (TDCPP), tri-ortho-cresyl phosphate (TOCP), and triphenyl phosphate (TPHP) increased in the GDM group, and the OPFRs and PAEs, except for BBP and TMCP, were associated with GDM in the logistic regression analysis. In the WQS model, the mixture of OPFRs and PAEs was significantly positively associated with GDM (OR = 3.29, 95%CI = 1.27–8.51, P = 0.014), with TDCPP having the highest WQS index weight. BKMR analysis reinforced these results, showing that the overall association of joint exposure to the OPFRs and PAEs with GDM increased at exposure levels of the 55th to 75th percentiles. Independent exposure to TDCPP (OR = 1.42, 95%CI = 1.09–1.86, P = 0.011) and TBEP (OR = 1.29, 95%CI = 1.04–1.60, P = 0.023) were associated with an increased risk of GDM.ConclusionsEnvironmental exposure to OPFRs and PAEs is significantly associated with GDM. These findings provide evidence for the adverse effects of exposure to OPFRs and PAEs on the health of pregnant women.

Recent advances of optical sensors for point-of-care detection of phthalic acid esters

Phthalic acid esters (PAEs) are often added to plastics to enhance elasticity, transparency, durability and prolong service life as a kind of plasticizer. However, they are not chemically bonded to polymers and are difficult to degrade, which makes it easy for them to release into the environment and enter the human body from various potential sources. This results in environmental pollution and poses health risks. In order to protect ecosystem, ensure food safety and prevent disease, there is an urgent need for sensors that can achieve point-of-care detection of PAEs. Optical sensors have advantages of simplicity, portability and low cost, and have been widely applied to the detection of PAEs. In this review, we focus on introducing the recent advancements and trends in optical sensors for detection of PAEs represented by colorimetric (CL) sensors, fluorescence (FL) sensors and surface-enhanced Raman scattering (SERS) platform. Based on recognition strategies (e.g., label-free, aptamer, molecularly imprinted polymer, antibody and enzyme), the significant achievements of these optical sensors in the past 5 years are systematically classified and described in detail. Researchers can quickly know the development status of optical sensors for detection of PAEs in the past 5 years. This review highlights the strengths of each sensor type while also identifying their application limitations, providing researchers with valuable insights into future directions for optical sensor research.

Environmental monitoring of phthalic acid esters in northwest Persian Gulf estuary: Concentrations, distribution, and risk assessment

The present study investigates the concentration level, distribution, and risk assessment of six high-priority phthalic acid esters (PAEs) in seawaters and sediments of the Musa estuary, northwest of the Persian Gulf, Iran. Additionally, the industrial and urban effluents terminating in this estuary were also analyzed. The overall variations of Σ6PAEs were 10.65–164.80 µg/L in seawaters, 0.53–26.18 µg/g in sediments, and 181.09–764.57 µg/L in effluent samples. Di–n–butyl phthalate (DnBP) and di(2–ethylhexyl) phthalate (DEHP), together accounted for 57.2 %–99.5 % and 59 %–100 % of the Σ6PAEs concentrations in seawaters and sediments, respectively. A relatively similar trend was also detected in the effluent waters. While industrial runoffs exhibited greater shares and concentrations compared to urban areas, the levels of PAEs were higher in waters and sediments near urban regions due to restricted water circulation. A significant correlation was found (r = 0.8385) between Σ6PAEs in seawater and sediment. Given its consistent detection frequency of 100 % across all stations, DEHP can be served as a reliable indicator for PAE contamination. In nearly all stations, the pollution levels of DnBP and DEHP exceeded the environmental risk level (ERL). The ecological risk quotient (RQ) for at least two PAEs appeared at medium to high levels in both seawaters and sediments. Establishing baseline data on PAEs in the Musa estuary will guide future strategies for pollutant control across the Persian Gulf network.

Levels, distribution, and health risk assessment of phthalic acid esters in urban surface soils of Nagpur city, India.

Surface soil samples from residential, commercial, and industrial areas of Nagpur city, India, were collected to study the levels, distribution, and impact of land use patterns on phthalic acid ester (PAEs) contamination. The Σ6PAEs concentrations in soils from residential, commercial, and industrial areas ranged between 6,493 to 13,195µg/kg, 707 to 18,446µg/kg, and 1,882 to 5,004µg/kg with medians of 10,399, 6,199, and 3,401µg/kg, respectively. Bis-2-ethylhexyl phthalate (DEHP) and dimethyl phthalate (DMP) were the dominant PAEs in the urban soils. The concentrations of DEHP and DMP were significantly greater than those in Ontario's soil quality guidelines. Among the PAEs, benzyl-butyl phthalate (BzBP) was found at relatively high concentrations (1,238 and 9,171µg/kg) at two locations (i.e., S1 and S15). The chronic toxic risk (CTR) of PAEs was below the threshold, although the risk to children through ingestion and dermal exposure routes was greater than that to adults. The CR due to BzBP and DEHP were below the threshold level; however, the CR due to DMP was > 1 × 10-6 in residential areas. The cumulative CR of the six PAEs for adults (1.33-1.41 × 10-5) and children (8.08-8.89 × 10-6) surpassed the threshold level. This study revealed that PAEs in urban soils pose a risk to public health and require immediate risk reduction strategies.

Machine Learning Models for Predicting Bioavailability of Traditional and Emerging Aromatic Contaminants in Plant Roots.

To predict the behavior of aromatic contaminants (ACs) in complex soil-plant systems, this study developed machine learning (ML) models to estimate the root concentration factor (RCF) of both traditional (e.g., polycyclic aromatic hydrocarbons, polychlorinated biphenyls) and emerging ACs (e.g., phthalate acid esters, aryl organophosphate esters). Four ML algorithms were employed, trained on a unified RCF dataset comprising 878 data points, covering 6 features of soil-plant cultivation systems and 98 molecular descriptors of 55 chemicals, including 29 emerging ACs. The gradient-boosted regression tree (GBRT) model demonstrated strong predictive performance, with a coefficient of determination (R2) of 0.75, a mean absolute error (MAE) of 0.11, and a root mean square error (RMSE) of 0.22, as validated by five-fold cross-validation. Multiple explanatory analyses highlighted the significance of soil organic matter (SOM), plant protein and lipid content, exposure time, and molecular descriptors related to electronegativity distribution pattern (GATS8e) and double-ring structure (fr_bicyclic). An increase in SOM was found to decrease the overall RCF, while other variables showed strong correlations within specific ranges. This GBRT model provides an important tool for assessing the environmental behaviors of ACs in soil-plant systems, thereby supporting further investigations into their ecological and human exposure risks.

Engineering bacterial biocatalysts for the degradation of phthalic acid esters.

Phthalic acid esters (PAEs) are synthetic diesters derived from o-phthalic acid, commonly used as plasticizers. These compounds pose significant environmental and health risks due to their ability to leach into the environment and act as endocrine disruptors, carcinogens, and mutagens. Consequently, PAEs are now considered major emerging contaminants and priority pollutants. Microbial degradation, primarily by bacteria and fungi, offers a promising method for PAEs bioremediation. This article highlights the current state of microbial PAEs degradation, focusing on the major bottlenecks and associated challenges. These include the identification of novel and more efficient PAE hydrolases to address the complexity of PAE mixtures in the environment, understanding PAEs uptake mechanisms, characterizing novel o-phthalate degradation pathways, and studying the regulatory network that controls the expression of PAE degradation genes. Future research directions include mitigating the impact of PAEs on health and ecosystems, developing biosensors for monitoring and measuring bioavailable PAEs concentrations, and valorizing these residues into other products of industrial interest, among others.

Migration patterns of phthalic acid esters from mulch plastic film in the soil-plant-atmosphere continuum system.

Plastic film mulching is an important agricultural practice, but its release of phthalic acid esters (PAEs) poses threats to soil and human health. However, the migration patterns of PAEs during the lifecycle of mulch plastic film (MPF) remain unclear. This study aims to explore the temporal patterns of release of PAEs during the MPF's lifecycle and evaluate the migration patterns of PAEs from MPF in the soil-plant-atmosphere continuum (SPAC) system through pot experiments and model simulations. The results reveal that during the mulching period, 44.90-56.71% of the PAEs released went into the atmosphere and 14.97-18.90% into the soil, while during the residual film period, 24.39-40.13% were slowly released into the soil. Elevated soil water content increased maize transpiration rates, leading to higher concentrations of PAEs in roots, stems, and fruits, but lower concentrations in leaves. In 2020, the estimated total release of PAEs from MPF in northwest China amounted to 35.42 tons. Notably, PAEs predominantly accumulated in the soil, with minimal accumulation in plant tissues. Moreover, PAEs were primarily removed through degradation. Our results elucidate the migration patterns of PAEs from MPF in the SPAC system, facilitating the evaluation of PAE pathways into the human food chain.

Biodegradation of phthalic acid esters by a novel marine bacterial strain RL-BY03: Characterization, metabolic pathway, bioaugmentation and genome analysis

Biodegradation is recognized as the main route for the decomposition of phthalic acid esters (PAEs) in nature, but the fate of PAEs in marine ecosystems is not well understood. Herein, a novel marine bacterium, Gordonia sihwaniensis RL-BY03, was identified and analyzed for its ability to degrade PAEs. Furthermore, the metabolic mechanism of di-(2-ethylhexyl) phthalate (DEHP) was examined through UPLC-MS/MS and genomic analysis. RL-BY03 could rely solely on several types of PAEs as its sole carbon source. Initial pH and temperature for DEHP degradation were optimized as 8.0 and 30°C, respectively. Surprisingly, RL-BY03 could simultaneously degrade ethyl acetate and DEHP and they could increase the cell surface hydrophobicity. DEHP degradation kinetics fitted well with the first-order decay model. The metabolic pathway of DEHP was deduced following the detection of five metabolic intermediates. Further, genes that are related to DEHP degradation were identified through genomic analysis and their expression levels were validated through RT-qPCR. A co-related metabolic pathway at biochemical and molecular level indicated that DEHP was turned into DBP and DEP by β-oxidation, which was further hydrolyzed into phthalic acid. Phthalic acid was utilized through catechol branch of β-ketoadipate pathway. Additionally, RL-BY03 exhibited excellent bioremediation potential for DEHP-contaminated marine samples. In general, these findings have the potential to enhance our understanding of the fate of PAEs in marine ecosystems.

Investigation of interaction mechanism between polyvinyl chloride microplastics and phthalate acid esters using APGC-MS/MS

Phthalate acid esters (PAEs) are a kind of typical endocrine disruptors chemicals (EDCs). PAEs can be enriched, migrated and released into organisms through microplastics (MPs), causing high toxicological risks. This study presented an atmospheric pressure gas chromatography-tandem mass spectrometry (APGC-MS/MS) method for 10 PAEs trace analysis. Based on this method, the interaction mechanism between polyvinyl chloride microplastics (PVC MPs) and PAEs was explored. The established APGC-MS/MS method achieved 10 PAEs analysis in 14 min with the satisfied detection limit as low as 0.0025 μg/L and excellent linearity (R2 = 0.99868–0.99996). The interaction mechanism investigation showed that PVC MPs had high adsorption and desorption capacities for PAEs. The adsorption mechanism involves adsorption distribution, surface adsorption, hydrophobic interaction and intermolecular van der Waals force. Temperature, diffusion channels, pore filling, hydrophobicity and solubilization may be potential desorption mechanisms. Moreover, the intestinal environment of warm-blood organisms has the highest bioavailability of PAEs. Overall, this APGC-MS/MS method of PAEs had the virtue of simplicity, efficiency, reliability and sensitivity, and could serve as a potential tool for risk analysis of MPs and PAEs exposure.

Dissolved and particulate phase phthalic acid esters in urban, suburban, and rural riverine catchments along the southeast coast of India after the COVID-19 pandemic

Dumped waste plastics have been evidenced as a potential source for harmful chemicals along the riverine regions of India. Furthermore, Corona Virus Disease – 19 (COVID-19) pandemic resulted in a subsequent surge in the use of personal protective equipment (PPE) related single-use plastics and Tamil Nadu was India's second major waste generator. Given the newer challenges from dumped waste plastics along the four major rivers of Tamil Nadu emptying into the Bay of Bengal, we investigated thirteen phthalic acid esters (PAEs), in both dissolved and particulate phases of river water and drinking water samples. Ʃ13PAEs in both phases followed the urban > suburban > rural catchment trend. Di (2-ethyl hexyl) phthalate (DEHP) was ubiquitous in both phases and the sites having a prevalence of open burning activities in the urban catchment showed elevated levels. The suburban and rural catchments of the Kaveri River (KR) and Thamirabharani River (TR) were predominated by DEP and DEHP. It is noteworthy that in the urban catchment, Ln (DiBP) and dissolved organic carbon (Ln DOC), were strongly correlated (R2 = 0.894, p < 0.05). Furthermore, a significant increase of DiBP (p < 0.05) in the urban catchment after the second phase of the pandemic most likely resulted from the wide use of DiBP in PPE plastics. Community-stored water from urban catchment was found to have a maximum of ∑13PAEs up to 3769.38 ng/L in the dissolved phase with elevated DMP concentrations leading to higher estrogenic equivalent. The average daily intake for dissolved phase PAEs was below the USEPA-recommended limit for drinking water. However, prolonged exposure to heavier PAEs in particulate matter cannot be ignored. Estimated ecotoxicological risk assessment showed the highest risk for fish species due to DEHP.

Single-step template-free synthesis of fluoro-functionalized covalent organic frameworks with a tunable hollow structure for extraction of phthalate acid esters from human urine

Phthalate acid esters (PAEs) are recognized as endocrine disruptors, exhibit carcinogenic characteristics, and have the potential to impair fertility, thereby posing significant risks to both the environment and human health. Consequently, biomonitoring and exposure assessment of PAEs are of paramount importance. Presently, the majority of detection methods for PAEs are centered on aqueous matrices, and the development of techniques for the identification of PAEs in complex matrices remains an area of active research. This paper designed and synthesized a novel fluoro-functionalized hollow covalent organic framework (F-HCOF), characterized by a tunable hollow spherical structure and enriched with fluorine functional groups, through a one-step self-template approach, which effectively regulated the formation of the hollow structure. The synthesized F-HCOF with tunable hollow structures and abundant F functional groups provided efficient diffusion pathways and adsorption sites, facilitating robust and selective adsorption of the target PAEs. Using F-HCOF as a coating, a solid-phase microextraction method was developed to extract PAEs from complex matrices. The method exhibited limits of detection ranging from 0.0108 to 0.0581 ng L−1, with enrichment factors spanning from 2535.3 to 8985.3. The self-made F-HCOF fibers demonstrated the capability to effectively enrich PAEs under various interference conditions, further verifying their feasibility for practical sample analysis. This work provided a strategic approach for the synthesis of F-functionalized hollow COF adsorbents and explored the formation process of hollow spheres. It enables matrix interference-resistant analysis of PAEs, and offers a practical method for studying PAEs exposure and metabolism within the human body.

Characterization and mechanism of phthalic acid esters bioaccumulation in dominant mangrove fish at different habitats in the mangrove ecosystem of Dongzhai Harbor, China

With the wide application of phthalic acid esters (PAEs) in the manufacturing of plastic products, a large number of PAEs were discharged into marine ecosystem and accumulated in fish, which has posed a serious threat to marine ecological environment and fishery resources. However, the bioaccumulation of PAEs in fish in mangrove ecosystem, the most productive marine ecosystem, has not been well characterized. In this study, dominant fish and their potential food sources (including particulate organic matter (POM), sedimentary organic matter (SOM), Metapenaeus ensis (Shrimp) and Oreochromis (Ore) were collected from Dongzhai Harbor, a typical mangrove ecosystem. The concentrations of nine PAEs in fish and their potential food sources were determined. Then stable nitrogen and carbon isotope analysis, combined with a new Bayesian mixing model (MixSIMMR) was used to quantify the diet compositions of fish and elucidate the effect of dietary habit on PAEs bioaccumulation in fish. The results indicated that the median concentration of ∑9PAEs in fish was 1119 μg/kg ww, positioning it at a moderate to low level in comparison to other regions. di-n-butyl phthalate (DBP) and diisononyl ortho-phthalate (DINP) were the dominant PAEs in fish. The PAEs concentration in demersal fish was significantly higher than that of pelagic fish, which may be attributed to the substantial contributions of shrimp (28.5 %) and POM (25.3 %) to the diet of demersal fish. This study provided new insights on the bioaccumulation of PAEs in dominant mangrove fish and confirmed that habitat preferences and food sources could significantly influence the bioaccumulation of PAEs in fish.

Analytical Investigation of Phthalates and Heavy Metals in Edible Ice from Vending Machines Connected to the Italian Water Supply.

Edible ice is often produced by special machines that can represent a source of significant chemical and microbiological contamination. In this work, the presence of phthalic acid esters (phthalates, PAEs) and heavy metals in ice cubes distributed by 77 vending machines installed in two different zones in southern Italy and fed by water from the public water supply was investigated. Solid-phase microextraction coupled to gas chromatography-mass spectrometry (SPME-GC/MS) was used to evaluate contamination with four PAEs, which were selected because they are commonly used in the production of food-contact plastics, while inductively coupled plasma mass spectrometry (ICP/MS) was used to quantify the heavy metals. It was found that ice samples, especially those from one of the two considered zones (zone 2), exceeded the dibutyl phthalate (DBP) threshold limit value; some ice cubes from the other zone (zone 1) instead showed levels of both lead (Pb) and nickel (Ni) up to one order of magnitude higher than those observed in samples collected in zone 2 and higher than the maximum permitted values (European Directive n. 2184/2020). Since the water source connected to the ice vending machines was found to be free from significant levels of all considered target compounds and metals, the high levels of DBP, Ni, and Pb in ice cubes could be attributed to the components and/or to the state of repair of the ice vending machines themselves.

Microbial dynamics, chemical profile, and bioactive potential of diverse Egyptian marine environments from archaeological wood to soda lake

Halophilic archaea are a unique group of microorganisms that thrive in high–salt environments, exhibiting remarkable adaptations to survive extreme conditions. Archaeological wood and El–Hamra Lake serve as a substrate for a diverse range of microorganisms, including archaea, although the exact role of archaea in archaeological wood biodeterioration remains unclear. The morphological and chemical characterizations of archaeological wood were evaluated using FTIR, SEM, and EDX. The degradation of polysaccharides was identified in Fourier transform infrared analysis (FTIR). The degradation of wood was observed through scanning electron microscopy (SEM). The energy dispersive X–ray spectroscopy (EDX) revealed the inclusion of minerals, such as calcium, silicon, iron, and sulfur, into archaeological wood structure during burial and subsequent interaction with the surrounding environment. Archaea may also be associated with detected silica in archaeological wood since several organosilicon compounds have been found in the crude extracts of archaeal cells. Archaeal species were isolated from water and sediment samples from various sites in El–Hamra Lake and identified as Natronococcus sp. strain WNHS2, Natrialba hulunbeirensisstrain WNHS14, Natrialba chahannaoensis strain WNHS9, and Natronococcus occultus strain WNHS5. Additionally, three archaeal isolates were obtained from archaeological wood samples and identified as Natrialba chahannaoensisstrain W15, Natrialba chahannaoensisstrain W22, and Natrialba chahannaoensisstrain W24. These archaeal isolates exhibited haloalkaliphilic characteristics since they could thrive in environments with high salinity and alkalinity. Crude extracts of archaeal cells were analyzed for the organic compounds using gas chromatography–mass spectrometry (GC–MS). A total of 59 compounds were identified, including free saturated and unsaturated fatty acids, saturated fatty acid esters, ethyl and methyl esters of unsaturated fatty acids, glycerides, phthalic acid esters, organosiloxane, terpene, alkane, alcohol, ketone, aldehyde, ester, ether, and aromatic compounds. Several organic compounds exhibited promising biological activities. FTIR spectroscopy revealed the presence of various functional groups, such as hydroxyl, carboxylate, siloxane, trimethylsilyl, and long acyl chains in the archaeal extracts. Furthermore, the archaeal extracts exhibited antioxidant effects. This study demonstrates the potential of archaeal extracts as a valuable source of bioactive compounds with pharmaceutical and biomedical applications.

Biodegradation of PAEs in contaminated soil by immobilized bacterial agent and the response of indigenous bacterial community

Phthalic acid esters (PAEs) are common hazardous organic contaminants in agricultural soil. Microbial remediation is an effective and eco-friendly method for eliminating PAEs. Nevertheless, the operational mode and potential application of immobilized microorganisms in PAEs-contaminated soil are poorly understood. In this study, we prepared an immobilized bacterial agent (IBA) using a cedar biochar carrier to investigate the removal efficiency of PAEs by IBA in the soil. We found that IBA degraded 88.35% of six optimal-control PAEs, with 99.62% biodegradation of low-molecular-weight PAEs (DMP, DEP, and DBP). The findings demonstrated that the IBA achieved high efficiency and a broad-spectrum in degrading PAEs. High-throughput sequencing revealed that IBA application altered the composition of the soil bacterial community, leading to an increase in the relative abundance of PAEs-degrading bacteria (Rhodococcus). Furthermore, co-occurrence network analysis indicated that IBA promoted microbial interactions within the soil community. This study introduces an efficient method for the sustainable remediation of PAEs-contaminated soil.

Detection and health implications of phthalates in tea beverages in market: Application of novel solid-phase microextraction fibers

Assessment and control of emerging organic pollutants in food have become critical for global food safety and health. The European Union has set standards for certain emerging organic pollutants, such as phthalic acid esters (PAEs) in food. Because of being endocrine disruptors, PAEs are toxic and carcinogenic to humans. Release of PAEs from packaging materials poses a potential risk to human health and causes environmental pollution. In this study, a highly sensitive analytical method for the detection of PAE contents in tea beverages was established using hydroxyl-functionalized covalent organic frameworks (COFs) as solid-phase microextraction (SPME) coating. Results indicate that functionalization with hydroxyl groups enhances the adsorption of PAEs. The proposed method exhibits a wide linear range (1–20,000 ng L−1), low limits of detection (> 0.048 ng L−1), and satisfactory recovery (72.8 %–127.3 %). To investigate the PAE contamination in beverages, contamination levels of six typical PAEs and their health impacts were surveyed across various brands/types/packaging materials of tea beverages sold in China. Results of the hazard quotient and hazard index approaches suggest no or extremely low health concerns regarding PAE levels. We observe that hydroxyl groups functionalized on COFs enhance the adsorption of PAEs. Moreover, an important outcome of this study is development of an efficient and sensitive direct detection method for PAEs in complex tea matrices, providing a reliable approach for the assessment of PAEs in other complex matrices.

Effect of mixed metal oxide‐based catalysts for the removal of hydrophobic phthalates from water

AbstractContaminants of emerging concern (CECs) such as phthalic acid esters (PAEs) are ubiquitous, toxic and persistent in aquatic environments. Current study explored mixed metal oxide catalysts derived from magnesium aluminium (MAH), magnesium aluminium ruthenium (MAR‐H), magnesium aluminium nickel (MANH) hydroxides and copper aluminium hydroxides of ammonium (CAM‐Am) and sodium molybdate (CAM‐Na) to remove dibutyl phthalate (DBP) and di‐2‐ethyl hexyl phthalate (DEHP) from water. Powder X‐ray diffraction (XRD) studies of the catalysts before and after the treatment showed that their structures were stable and robust. During Fourier Transform Infrared (FTIR) studies, vibrational bands or peaks of ester and alkane functional groups of DBP and DEHP were observed at all the catalysts after treatment. Thermogravimetric analysis (TGA) confirmed phthalate adsorption at the five catalysts. Hydrolysis of DBP and DEHP was observed during treatment using CAM‐Am and CAM‐Na that was analysed and quantified using total organic carbon (TOC), high performance liquid chromatography (HPLC) and high‐resolution mass spectrometry (HRMS). From TOC analyses, optimal conditions of 500 mg L−1 catalyst dosage and 30 h treatment time were deduced for catalytic hydrolysis of DBP and DEHP. Present study illustrated that the catalysts MAH and MANH can adsorb PAEs while CAM‐Na can adsorb and hydrolyse them.

Whole-cell biocatalysis for phthalate esters biodegradation in wastewater by a saline soil bacteria SSB-consortium

Phthalic acid esters (PAE) are widely used as plasticizers and have been classified as ubiquitous environmental contaminants of primary concern. PAE have accumulated intensively in surface water, groundwater, and wastewaters; thus, PAE degradation is essential. In the present study, the ability of a saline soil bacteria (SSB)-consortium to degrade synthetic wastewater-phthalates with alkyl chains of different lengths, such as diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), and di (2-ethylhexyl) phthalate (DEHP) was characterized. A central composite design-response surface methodology was applied to optimize the degradation of each phthalate, where the independent variables were temperature (21–41 °C), pH (5.3–8.6) and PAE concentration (79.5–920.4 mg L−1), and Gas Chromatography-Mass Spectrometry was used to identify the metabolites generated during phthalate degradation. Optimal conditions were 31 °C, pH 7.0, and an initial PAE concentration of 500 mg L−1, where the SSB-consortium removed 84.9%, 98.47%, 99.09% and 98.25% of initial DEP, DBP, BBP, and DEHP, respectively, in 168h. A first-order kinetic model explained - the biodegradation progression, while the half-life of PAE degradation ranged from 12.8 to 29.8 h. Genera distribution of the SSB-consortium was determined by bacterial meta-taxonomic analysis. Serratia, Methylobacillus, Acrhomobacter, and Pseudomonas were the predominant genera; however, the type of phthalate directly affected their distribution. Scanning electron microscopy analysis showed that high concentrations (1000 mg L−1) of phthalates induced morphological alterations in the bacterial SSB-consortium. The metabolite profiling showed that DEP, DBP, BBP, and DEHP could be fully metabolized through the de-esterification and β-oxidation pathways. Therefore, the SSB-consortium can be considered a potential candidate for bioremediation of complex phthalate-contaminated water resources.

Fabrication of macroporous POMs/biochar materials for fast degradation of phthalic acid esters through adsorption coupled with aerobic oxidation

Fabrication of macroporous POMs/biochar materials for fast degradation of phthalic acid esters through adsorption coupled with aerobic oxidation

Contamination of Phthalic Acid Esters (PAEs) in Surface Sediment Samples Collected from Rao Cai River in Ha Tinh, Vietnam

In this report, the solid phase extraction technique combined with the gas chromatography-mass spectrometry method (GC-MS) was optimized to determine the contamination of nine phthalic acid esters (PAEs) in the surface sediment samples collected from Rao Cai River in Ha Tinh, Vietnam. The method detection limits (MDLs) were from 2.0 to 6.0 ng/g-dry weight (ng/g-dw). The recoveries of surrogate standards (PAE-d4) in both blank and real samples ranged from 79.6 to 94.3% (RSD &lt; 8.7%). The total concentration of PAEs in the surface sediment samples was in the range of 72.4-1390 ng/g-dw (mean/median: 561/552 ng/g-dw). Among PAEs, di-(2-ethyl)hexyl phthalate (DEHP) was detected at the highest level in all samples. In contrast, dimethyl phthalate (DMP), diethyl phthalate (DEP), and dipropyl phthalate (DPP) were found at low frequency and concentration. Moreover, the risk quotient of PAEs in sediments was estimated based on the measured concentrations. Diisobutyl phthalate (DiBP) posed a medium risk for fish.