DEHP Research Articles

Suspect and non-targeted screening of chemical pollutants in Botswana's aquatic environments

Chemical pollution in the aquatic systems of Botswana has been sparsely studied despite its potential ecological importance. Here, we perform a study of water samples collected from 13 locations distributed across Botswana to obtain the first overview of the nature and distribution of chemical contaminants across the country's aquatic environment. High resolution mass spectrometry was applied using non-targeted and suspect screening methods to qualitatively analyse samples. A total of 114 contaminants of emerging concern (CECs) were identified including 68 (59.6 %) pharmaceuticals and pharmaceutical metabolites; 16 (14.2 %) pesticides; 13 (11.4 %) psychoactive compounds and metabolites; 11 (9.7 %) industrial chemicals and intermediates and lastly, 5 (4.4 %) personal care products. Allopurinol, 3,4-dimethylmethcathinone, and diazolidinyl urea represented the most commonly detected pharmaceutical, psychoactive drug and personal care product, respectively. The pesticide dodemorph and three industrial chemicals (stearamide, pthalic acid and bis(2-ethylhexyl) phthalate) were detected in all samples obtained. 90 CECs were detected in receiving water (from 7 sample locations), 75 in wastewater (from 3 sample locations) and 60 in surface water (from 9 sample locations). Of the compounds detected, only 8 had been identified in environmental samples acquired in Botswana previously. We discuss the variations in the nature and frequency of chemical pollutants detected in this work in a geographical context. The results indicate that Botswana's aquatic systems are subject to pollution, despite wastewater treatment and that in order to mitigate potentially harmful effects on both human and aquatic ecosystems, more investigations are required to correctly identify, track and tackle the sources of pollution.

High concentrations of phthalates affect the early development of the sea urchin Paracentrotus lividus

The toxicity of three phthalates (PAEs) - butylbenzyl phthalate (BBP), diethyl phthalate (DEP), and di-(2-ethylhexyl) phthalate (DEHP) - was tested on the Mediterranean sea urchin Paracentrotus lividus. Fertilized eggs were exposed to environmental and high PAE concentrations for 72 h. The potential toxic effects on larval development and any morphological anomalies were then assessed to estimate PAEs impact. Environmental concentrations never affected development, while high concentrations induced toxic effects in larvae exposed to BBP (EC50: 2.9 ×103 µg/L) and DEHP (EC50: 3.72 ×103 µg/L). High concentrations caused skeletal anomalies, with a slight to moderate impact for DEP/DEHP and BBP, respectively. PAE toxicity was: BBP>DEHP>DEP. In conclusion, the three PAEs at environmental concentrations do not pose a risk to sea urchins. However, PAE concentrations should be further monitored in order not to constitute a concern to marine species, especially at their early developmental stages.

Current Phthalate Exposure Risks of Rural Population in the Northwest China: Evidence from an Internal Exposure Study.

Phthalates (PAEs) are synthetic chemicals widely used in industrial and personal consumer products as adhesives or plasticizers. PAEs have been demonstrated to have toxic effects on the human body. However, biological monitoring data for the internal PAE exposure levels of Chinese rural residents are still limited. The present study investigated the exposure levels of ten phthalate metabolites (mPAEs) of rural residents in Northwest China. The results showed that mPAEs were wildly prevalent in urine and the geometric mean concentration of Σ10mPAEs was 957.02 ng mL-1 (adjusted by specific gravity). Mono-n-butyl phthalate (MBP) and metabolites of di(2-ethylhexyl)-phthalate (DEHP) were the most dominant mPAEs in urine, with specific gravity adjusted median concentrations of 174.67 and 156.30 ng mL-1, respectively. Urinary concentrations of mPAEs were significantly associated with age, body mass index and economic level (p < 0.05). By calculating the percentage and relative conversion rate of DEHP metabolites, it was found that the degree of oxidative metabolism of DEHP in children was significantly higher than that in adults (p < 0.05), indicating that the pathway and degree of DEHP oxidation were age-related. The risk assessment showed that 59.12% of rural residents may have a noncancer risk from PAE exposure. This study provides important basis for assessing the occurrence and exposure of urinary phthalate metabolites among rural residents in China.

SnO2/Au Microelectromechanical Systems Modified by Oxygen Vacancies for Enhanced Sensing of Dioctyl Phthalate.

Dioctyl phthalate (DOP) serves as a characteristic gas utilized in early electrical fire detection, its detection offers promising prospects for the prevention of electrical fires. In this study, we employed a modified photodeposition method to prepare Tin dioxide (SnO2) materials co-modified with Au and oxygen vacancies. Subsequently, microelectromechanical systems (MEMS) gas sensor for DOP detection were fabricated, utilizing 0.5 %Au/SnO2-I as the sensing material. Characterization results reveal the presence of abundant oxygen vacancies in 0.5 %Au/SnO2-I. The synergistic interplay of Au and oxygen vacancies resulted in a remarkable response of 9.98 to 20 ppm of DOP at operational temperature of 250 °C. This represents a significant 96 % enhancement in comparison to the response value of 4.50 exhibited by pure SnO2 at 300 °C. Notably, this gas sensor boasts low power consumption and demonstrates a quick response in the detection of overheating polyvinyl chloride (PVC) cables under simulated conditions.

Anthropogenic organic matter influence on epicuticular Tillandsia stricta Sol. ex Sims and Tillandsia usneoides (L.) L. (Bromeliaceae) wax leaf from Rio de Janeiro sandbank

Epicuticular wax from the leaves of Tillandsia stricta Sol. Sims and Tillandsia usneoides (L.) from Grumari, Marica and Jurubatiba, Rio de Janeiro sandbanks was extracted into chloroform and n-hexane for analyses. The extracts were subjected to gas chromatography (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS) analyses. In the investigated species, the major n-alkane was found to be C-27. This study has shown that the relation of n-alkanes and fatty acids is a function of the species and the triterpenoids were only observed in the wax of T. usneoides. Phthalates: di-n-octyl phthalate (DNOP), di isobutyl phthalate (DIBP); Di (2-ethylhexyl) phthalate (DEHP), benzoic acid, adipic acid derivatives were also detected beyond of DDT in T. stricta from the Conservation Unit of Jurubatiba. The exposure of T. usneoides to vehicular emission resulted in the reversal of the relationship fatty acid: n-alkanes and the triterpenoids suppression. These results reflect the importance of plants in monitoring environmental purposes and their potential for DDT and phthalates indicator.

Degradation of Di (2-ethylhexyl) phthalic acid plasticizer in baijiu by a foam titanium flow reactor attached with hairpin-like structured peptide enzyme mimics

Because of the significant environmental and health hazards imposed by di(2-ethylhexyl) phthalate (DEHP), a common plasticizer, developing safe and green techniques to degrade DEHP plasticizer is of huge scientific significance. It has been observed that environmental contamination of DEHP may also induce serious food safety problems because crops raised in plasticizers contaminated soils would transfer the plasticizer into foods, such as Baijiu. Additionally, when plastic packaging or vessels are used during Baijiu fermentation and processing, plasticizer compounds frequently migrate and contaminate the product. In this study, hairpin-like structured peptides with catalytically active sites containing serine, histidine and aspartic acid were found to degrade DEHP. Furthermore, after incorporating caffeic acid molecules at the N-terminus, the peptides could be attached onto foam titanium (Ti) surfaces via enediol-metal interactions to create an enzyme-mimicking flow reactor for the degradation of DEHP in Baijiu. The structure and catalytic activity of peptides, their interaction with DEHP substrate and the hydrolysis mechanism of DEHP were discussed in this work. The stability and reusability of the peptide-modified foam Ti flow reactor were also investigated. This approach provides an effective technique for the degradation of plasticizer compounds.

Synthesis, characterization and performance evaluation of different alkyl chain lengths flame-retardant plasticizers for poly(vinyl chloride) derived from sustainable vanillic acid

The current market for poly(vinyl chloride) (PVC) plasticizers is dominated by flammable petroleum-based compounds, accounting for over 80 % of the total share. Due to their high flammability, the search for novel approaches to enhance the fire resistance of flexible PVC has gained urgency. However, traditional flame-retardant schemes suffer from shortcomings such as poor compatibility, inferior long-term performance, and weak mechanical properties. Herein, we synthesized a novel biobased flame-retardant plasticizer (VAn-P) using vanillic acid as a skeleton. This plasticizer exhibits remarkable properties, including a substantially lower glass transition temperature compared to unplasticized PVC. The binding energy between VAn-P and PVC is calculated to be –33.30 kcal/mole, indicating a strong interaction. Furthermore, the maximum elongation at break of VAn-P plasticized PVC is 16 times higher than that of unmodified PVC. All PVC samples plasticized with VAn-P achieved a UL-94 VTM-0 rating. TGA-FTIR analysis revealed that the flame-retarding mechanism of VAn-P involves solid-phase action, significantly delaying the dehydrochlorination process of PVC. Moreover, VAn-P exhibits superior migration resistance compared to dioctyl phthalate (DOP). We also investigated the effects of alkyl chain lengths in VAn-P on various properties of PVC blends, including thermal stability, flame retardancy, mechanical properties, and optical performance. The toxicity of vanillic acid-based flame-retardant plasticizer has undergone an initial assessment. Overall, this green plasticizer is expected to endow polymers with high plasticizing performance and flame retardancy, providing a novel and sustainable approach for the synthesis of functional plasticizers.

Subacute exposure to DEHP leads to impaired decidual reaction and exacerbates the risk of early miscarriage in mice.

To investigate the effect of subacute exposure of Di (2-ethylhexyl) phthalate (DEHP) on endometrial decidualization and early pregnancy miscarriage in mice. CD1 mice were orally administrated with 300 (low-dose group), 1000 (medium-dose group), or 3000 mg·kg－1·d－1 DEHP (1/10 LD50, high-dose group) for 28 days, respectively. An early natural pregnancy model and an artificially induced decidualization model were established. The uterine tissues were collected on D7 of natural pregnancy and D8 of artificially induced decidualization, respectively. The effects of a subacute exposure to DEHP on the decidualization of mice were detected by HE staining, Masson staining, TUNEL assay, and Western blotting. A model of spontaneous abortion was constructed in mice after subacute exposure to 300 mg·kg－1·d－1 DEHP, and the effect of impaired decidualization on pregnancy was investigated by observing the pregnancy outcome on the 10th day of gestation. Compared with the control group, the conception rate was significantly decreased in the high-dose DEHP subacute exposure group (P<0.05). HE staining showed that, compared with the control group, the decidual stromal cells in the low- and medium-dose exposure groups were disorganized, the nuclei of the cells were irregular, the cytoplasmic staining was uneven, and the number of polymorphonuclear cells was significantly reduced. Masson staining showed that compared with the control group, the collagen fibers in the decidua region of the DEHP low-dose group and the medium-dose group were more distributed, more abundant and more disorderly. TUNEL assay showed increased apoptosis in the decidua area compared to the control group. Western blotting showed that the expression of BMP2, a marker molecule for endometrial decidualization, was significantly reduced (P<0.05 or P<0.01). The abortion rate and embryo resorption rate were increased, and the number of embryos, uterine wet weight, uterine area and placenta wet weight were decreased in DEHP low-dose group compared to the control group stimulated by mifepristone, an abortifacient drug (P<0.05 or P<0.01). Subacute exposure to DEHP leads to impaired endometrial decidualization during early pregnancy and exacerbates the risk of adverse pregnancy outcomes in mice.

The potential of chitosan intercalated nickel/iron layered double hydroxide composites as extraction adsorbent for phthalates

In this research, the potential utility of chitosan-nickel/iron LDHs (CS-Ni/Fe LDHs) has been examined for the separation and pre-concentration of five phthalates (PAEs: diethylphthalate (DEP), dipropylphthalate (DPP), dibutylphthalate (DBP), benzylbutylphthalate (BBP), and dioctylphthalate (DOP)). The extraction efficiency of CS-Ni/Fe LDH composites against the target phthalates is studied through the control of the key variables (e.g., eluent type, elution volume, flow rate, adsorbent amount, solution pH, and salt addition effect). Under the optimal conditions, the method detection limit towards target PAEs is estimated as 0.023–0.033 ng/mL over a 0.1–100 ng/mL range (R2>0.999). The CS-Ni/Fe LDH composites are utilized successfully to extract PAEs in real samples such as perfume, cream, bottled water, and bottled milk (recovery: 97.3–136.8%). The spent CS-Ni/Fe LDH composites can be regenerated at least over 30 cycles. The good agreement in adsorption isotherms with the non-linear Langmuir model indicates the formation of monolayered PAE molecules over CS-Ni/Fe LDH composites. The computed partition coefficients (mg g−1μM−1) for CS-Ni/Fe LDH are found as follows: DOP (802) > DBP (491) > DPP (355) > DEP (248) > BBP (247). The thermodynamic analysis reveals the exothermic and spontaneous behavior of the adsorption process. The CS-Ni/Fe LDHs are thus identified as efficient sorbent media for PAEs through hydrogen bonding and hydrophobic interactions. Accordingly, CS-Ni/Fe LDH composites are recommended as a useful option for capturing PAEs under real-world conditions.

Root-zone regulation and longitudinal translocation cause intervarietal differences for phthalates accumulation in vegetables

Selecting and cultivating low-accumulating crop varieties (LACVs) is the most effective strategy for the safe utilization of di-(2-ethylhexyl) phthalate (DEHP)-contaminated soils, promoting cleaner agricultural production. However, the adsorption-absorption-translocation mechanisms of DEHP along the root-shoot axis remains a formidable challenge to be solved, especially for the research and application of LACV, which are rarely reported. Here, systematic analyses of the root surface ad/desorption, root apexes longitudinal allocation, uptake and translocation pathway of DEHP in LACV were investigated compared with those in a high-accumulating crop variety (HACV) in terms of the root-shoot axis. Results indicated that DEHP adsorption was enhanced in HACV by root properties, elemental composition and functional groups, but the desorption of DEHP was greater in LACV than HACV. The migration of DEHP across the root surface was controlled by the longitudinal partitioning process mediated by root tips, where more DEHP accumulated in the root cap and meristem of LACV due to greater cell proliferation. Furthermore, the longitudinal translocation of DEHP in LACV was reduced, as evidenced by an increased proportion of DEHP in the root apoplast. The symplastic uptake and xylem translocation of DEHP were suppressed more effectively in LACV than HACV, because DEHP translocation in LACV required more energy, binding sites and transpiration. These results revealed the multifaceted regulation of DEHP accumulation in different choysum (Brassica parachinensis L.) varieties and quantified the pivotal regulatory processes integral to LACV formation.

Influence of Ascorbic Acid on Di-(2-Ethylhexyl) Phthalate-induced Ovarian Gene Alterations in Pubertal Female Wistar Rats

Background Di-(2-ethylhexyl) phthalate (DEHP), a plasticizer compound affecting female reproduction, leads to scenarios, such as polycystic ovarian syndrome (PCOS) and infertility through oxidative stress (OS) mechanisms. Ascorbic acid (AA) is one of the antioxidants in infertility issues. Objectives The present study investigates the ameliorative effect of AA on DEHP-induced ovarian toxicity in pubertal female Wistar rats. Materials and Methods Thirty female Wistar rats of four weeks of age were stratified into five groups. Group I was treated with corn oil (Vehicle), groups II and III with low and high dose DEHP, and groups IV and V with low and high dose DEHP+AA were administered for 30 days. Results Increased body weight gain was noted in DEHP groups. Estradiol hormone was considerably reduced, whereas progesterone levels were increased in both low- and high-dose DEHP-treated groups. DEHP+AA groups have shown significant ( p &lt; 0.005) protection of these hormone levels as equal to the control group. The high-dose DEHP group shows an increased, ovarian estrogen receptor (ER) alpha, ER-beta, and progesterone receptor gene expression, and DEHP+AA groups have significantly ( p &lt; 0.005) showed expression similar to the control. OS was noted with decreased superoxide dismutase and increased malondialdehyde expression in Group III (GR III) compared to control, whereas the DEHP+AA treated group significantly protected OS by restoring the expression levels. DEHP-treated groups show elevated levels of both Bcl-2 and BAX which is specific to apoptotic expression and restored by AA treatment ( p &lt; 0.005). Conclusion Evidence suggests that AA may protect against DEHP-induced ovarian toxicity by decreasing OS levels, improving folliculogenesis, and restoring the hormonal with receptor level alterations.

Influence of compatibilization methods on the compatibility between asphalt and DCLR components with molecular dynamics (MD) method

This study aims to investigate the effect of compatibilization methods on the compatibility between asphalt and direct coal liquefaction residue (DCLR) components to identify the key components in DCLR and asphalt that affect their compatibility. In this article, three types of compatibilizers, including benzyl alcohol (BA), dioctyl phthalate (DOP), and BA/DOP, were selected and acted on asphalt's components and DCLR's components, respectively. The molecular models of asphalt components, asphalt components with compatibilizers, DCLR components, and DCLR components with compatibilizers were established. The compatibility between DCLR and asphalt's four components, as well as between asphalt and DCLR's three components, were evaluated by solubility parameter difference (SPD) and interaction energy (IE). The compatibility between DCLR and asphalt was analyzed by Segregation test and Scanning Electron Microscope. Results indicate that the SPD and IE values between DCLR and asphalt components declined after adding compatibilizers, which implies that the repulsion decreased and the attraction increased between asphalt components and DCLR and the compatibility between asphalt components and DCLR improved. The IE values between DCLR components and asphalt increased after adding compatibilizers, which indicates that the compatibility was reduced between DCLR components and asphalt. The SPD values between DCLR components and asphalt increased after adding the BA/DOP. The SPD values between pre-asphaltene and asphalt decreased after adding the BA and DOP. The SPD value between asphaltene in DCLR and asphalt increased after adding the BA and decreased after adding the DOP. Moreover, the storage stability and homogeneity of DCLR-modified asphalt improved after adding compatibilizers, indicating that the compatibilizers enhanced compatibility between DCLR and asphalt. Finally, comparing the results of the tests, it could be found that compatibilizers preferentially acted on the asphalt components and mainly affected the aromatics in asphalt, thereby improving the compatibility between asphalt and DCLR. The effect of BA/DOP on improving the compatibility between asphalt and DCLR was better than that of BA and DOP.

Phthalic acid esters: Are they a big concern for rivers flowing into reservoir with ecological facilities?

The city-river-reservoir system is an important system for safeguarding drinking water. Phthalic acid esters (PAEs) are emerging contaminants in drinking water sources that are gaining attention, and they could pose risks to human health and aquatic organisms. In this study, field studies that lasted four years were conducted to analyze the concentrations, spatial-temporal distribution, and removal effects of six PAEs. The total concentrations of the Σ6PAEs in the water and sediment samples were 0.2–7.4 μg L−1 (mean: 1.3 μg L−1) and 9.2–9594.1 ng g−1 (mean: 847.5 ng g−1), respectively. Di-n-butyl phthalate (DBP) and, bis(2-ethylhexyl) phthalate (DEHP) were the predominant congeners, accounting for 57.2 % in the water samples and 94.1 % in the sediment samples. The urban area contributed 72 % of the PAEs in the system. A significant removal effect of PAEs was observed in the wetland, with a removal rate of 40.2 %. The partitioning of PAEs between the water and sediment was attributed to the removal of dimethyl phthalate and diethyl phthalate that occurred during the water phase, while the removal of DBP and DEHP primarily occurred during the sediment phase. The ecological risk calculation based on the sensitivity distribution model indicated that DBP (HQwater = 0.19, HQsediment = 0.46) and DEHP (HQwater = 0.20, HQsediment = 0.13) possessed moderate risks according to some water and sediment samples. The ecological projects were verified to be effective engineering strategies to reduce ecological risk in the drinking water source.

Near-infrared light-driven lab-on-paper cathodic photoelectrochemical aptasensing for di(2-ethylhexyl)phthalate based on AgInS2/Cu2O/FeOOH photocathode

Di(2-ethylhexyl)phthalate (DEHP) is commonly released from plastics in aqueous environment, which can disrupt endocrine system and cause adverse effects on public health. There is a pressing need to highly sensitive detect DEHP. Herein, a near-infrared (NIR) light-driven lab-on-paper cathodic photoelectrochemical aptasensing platform integrated with AgInS2/Cu2O/FeOOH photocathode and “Y”-like ternary conjugated DNA nanostructure-mediated “ON-OFF” catalytic switching of hemin monomer-to-dimer was established for ultrasensitive DEHP detection. Profiting from the collaborative roles of the effective photosensitization of NIR-response AgInS2 and the fast hole extraction of FeOOH, the NIR light-activated AgInS2/Cu2O/FeOOH photocathode generated a markedly enhanced photocathodic signal. The dual hemin-labelled “Y”-like ternary conjugated DNA nanostructures made the hemin monomers separated in space and they maintained highly active to catalyze in situ generation of electron acceptors (O2). The hemin monomers were relocated in close proximity with the help of target-induced allosteric change of DNA nanostructures, which could spontaneously dimerize into catalytically inactive hemin dimers and fail to mediate electron acceptors generation, resulting in a decreased photocathodic signal. Therefore, the ultrasensitive DEHP detection was realized with a linear response range of 1 pM–500 nM and a detection limit of 0.39 pM. This work rendered a promising prototype to construct powerful paper-based photocathodic aptasensing system for sensitive and accurate screening of DEHP in aqueous environment.

Single-cell insights into mouse testicular toxicity under peripubertal exposure to di(2-ethylhexyl) phthalate.

Male fertility depends on normal pubertal development. Di-(2-ethylhexyl) phthalate (DEHP) is a potent antiandrogen chemical, and exposure to DEHP during peripuberty can damage the developing male reproductive system, especially the testis. However, the specific cellular targets and differentiation processes affected by DEHP, which lead to testicular toxicity, remain poorly defined. Herein, we presented the first single-cell transcriptomic profile of the pubertal mouse testis following DEHP exposure. To carry out the experiment, 2 groups (n = 8 each) of 3-week-old male mice were orally administered 0.5% carboxymethylcellulose sodium salt or 100 mg/kg body weight DEHP daily from postnatal day 21-48, respectively. Using single-cell RNA sequencing, a total of 31 distinct cell populations were identified, notably, Sertoli and Leydig cells emerged as important targets of DEHP. DEHP exposure significantly decreased the proportions of Sertoli cell clusters expressing mature Sertoli markers (Sox9 and Ar), and selectively reduced the expression of testosterone synthesis genes in fetal Leydig cells. Through cell-cell interaction analyses, we observed changed numbers of interactions in Sertoli cells 1 (SCs1), Leydig cells 1 (LCs1), and interstitial macrophages, and we also identified cell-specific ligand gene expressions in these clusters, such as Inha, Fyn, Vcam1, and Apoe. Complementary in vitro assays confirmed that DEHP directly reduced the expression of genes related to Sertoli cell adhesion and intercellular communication. In conclusion, peripubertal DEHP exposure reduced the number of mature Sertoli cells and may disrupt testicular steroidogenesis by affecting the testosterone synthesis genes in fetal Leydig cells rather than adult Leydig cells.

Protective Effects of Polysaccharide of Atractylodes Macrocephala Koidz against Porcine Aortic Valve Endothelial Cells Damage Induced by di (2-ethylhexyl) Phthalate.

The activation, injury, and dysfunction of endothelial cells are considered to be the initial key events in the development of atherosclerosis. Di (2-ethylhexyl) phthalate (DEHP), a prevalent organic pollutant, can cause damage to multiple organs. Polysaccharide of Atractylodes macrocephala Koidz (PAMK) is a bioactive compound extracted from A. macrocephala Koidz with various biological activities. This study investigates the protective effects of PAMK on porcine aortic valve endothelial cells (PAVEC) damaged by DEHP. PAVECs treated with DEHP alone or with PAMK showed reduced cell apoptosis and death in PAMK-pretreated cells. PAMK up-regulated Bcl-2 expression and down-regulated Bax protein, suppressing apoptosis. Flow cytometry analysis demonstrated that PAMK protected PAVECs from DEHP-induced damage. These findings suggest that PAMK inhibits cell apoptosis and protects against DEHP damage in endothelial cells.

Exploring di (2-ethylhexyl) phthalate degradation by a synthetic marine bacterial consortium: Genomic insights, pathway and interaction prediction, and application in sediment microcosms

Di (2-ethylhexyl) phthalate (DEHP), a toxic phthalate ester (PAE) plasticizer, is often detected in marine sediment and biota. Our understanding of DEHP-degrading marine bacteria and the associated genetic mechanisms is limited. This study established a synthetic bacterial consortium (A02) consisting of three marine bacteria (OR05, OR16, and OR21). Consortium A02 outperformed the individual strains in DEHP degradation. Investigations into the degradation of DEHP intermediates revealed that OR05 and OR16 likely contributed to enhanced DEHP degradation by Consortium A02 via the utilization of DEHP intermediates, such as protocatechuic acid and mono (ethylhexyl) phthalate, with OR21 as the key DEHP degrader. A pathway of DEHP degradation by Consortium A02 was predicted based on genome analysis and experimental degradation. Bioaugmentation with Consortium A02 led to 80% DEHP degradation in 26 days in saline sediment (100 mg/kg), surpassing the 53% degradation by indigenous microbes, indicating the potential of A02 for treating DEHP-contaminated sediments. Meanwhile, bioaugmentation notably changed the bacterial community, with the exclusive presence of certain bacterial genera in the A02 bioaugmented microcosms, and was predicted to result in a more dynamic and active sediment bacterial community. This study contributes to the limited literature on DEHP degradation by marine bacteria and their associated genes.

Plasticizers inhibit food waste anaerobic digestion performance by affecting microbial succession and metabolism

The widely existed plastic additives plasticizers in organic wastes possibly pose negative influences on anaerobic digestion (AD) performance, the direct evidence about the effects of plasticizers on AD performance is still lacking. This study evaluated the influencing mechanism of two typical plasticizers bisphenol A (BPA) and dioctyl phthalate on the whole AD process. Results indicated that plasticizers addition inhibited methane production, and the inhibiting effects were reinforced with the increase of concentration. By contrast, 50 mg/L BPA exhibited the strongest inhibition on methane production. Physicochemical analysis showed plasticizers inhibited the metabolism efficiency of soluble polysaccharide and volatile fatty acids. Microbial communities analyses suggested that plasticizers inhibited the direct interspecies electron transfer participators of methanogenic archaea (especially Methanosarcina) and syntrophic bacteria. Furthermore, plasticizers inhibited the methane metabolisms, key coenzymes (CoB, CoM, CoF420 and methanofuran) biosynthesis and the metabolisms of major organic matters. This study shed light on the effects of plasticizers on AD performance and provided new insights for assessing the influences of plasticizers or plastic additives on the disposal of organic wastes.

Polypropylene membranes prepared via non-solvent/thermally induced phase separation: Effect of non-solvent nature

The goal of this work was to investigate the effect of non-solvent nature on the formation of porous membranes via non-solvent/thermally induced phase separation (N-TIPS). The hot solution of polypropylene (PP) in a mixture of dioctyl phthalate (DOP) and dibutyl phthalate (DBP) at 210 °C was placed as a thin film on a polyethylene terephthalate (PET) substrate, and then precipitated by immersion in the non-solvent (water, iso-propanol, 1-hexanol, or 1-decanol) at room temperature. It was found that the non-solvent nature greatly affected the morphology of the thin skin layer of the membrane facing the precipitation bath, which can be attributed to non-solvent induced phase separation (NIPS). The affinity between the polymeric solution and corresponding non-solvent was evaluated by using Hansen solubility parameters of components taken at room temperature and extrapolated to the temperature of 210 °C. An increase in the affinity between the non-solvent and the polymer transformed the surface layer structure from almost monolithic to cellular (with different pore sizes and porosity) and to spherulitic types. The non-solvent nature played a less pronounced role in the formation of the porous structure of the membrane bulk and the back side of the membrane (facing the PET substrate). Since the morphology of the rest of the membrane was correlated with thermophysical properties of non-solvents, it was concluded that the membrane formation took place due to temperature induced phase separation (TIPS). In the case of water, which has the highest cooling rate, the polypropylene crystallized by forming a “smectic” structure, while the standard α-lamellar structure was observed for other non-solvents. To gain insight into the TIPS process, a model of unsteady one-dimensional heat transfer was applied to simulate the change in the temperature profile of the hot, thin film of polymeric solution placed in the corresponding non-solvent. The resulting membranes were mainly in the microfiltration range with a mean through pore size of 0.05–0.61 μm, and iso-propanol permeance of 2.1–8.4 m3 m−2∙h−1∙bar−1. The rejection of 500 nm polystyrene microspheres was in the range of 45–98 %. The tensile strength was in the range of 2.9–3.2 MPa, and elongation at break was 30–190 % with respect to the non-solvent used.

Risk assessment of China’s Eastern Route of the South-to-north Water Diversion Project from the perspective of Phthalate Esters occurrence in the impounded lakes

Phthalate esters (PAEs) are widely utilized and can accumulate in lacustrine ecosystems, posing significant ecological and human health hazards. Most studies on PAEs focus on individual lakes, lacking a comprehensive and systematic perspective. In response, we have focused our investigation on characteristic lakes situated along the Eastern Route of the South-to-north Water Diversion Project (SNWDP-ER) in China. We have detected 16 PAE compounds in the impounded lakes of the SNWDP-ER by collecting surface water samples using solid-phase extraction followed by gas chromatography analysis. The concentration of PAEs were found to between 0.80 to 12.92 μg L−1. Among them, Bis (2-ethylhexyl) phthalate (DEHP) was the most prevalent, with mean concentration of 1.56 ± 0.62 μg L−1 (48.44%), followed by Diisobutyl phthalate (DIBP), 0.64 ± 1.40 μg L−1 (19.87%). Spatial distribution showed an increasing trend in the direction of water flow. Retention of DEHP and DIBP has led to increased environmental risks. DEHP, Dimethyl phthalate (DMP) etc. determined by agriculture and human activities. Additionally, Dibutyl phthalate (DBP) and DIBP mainly related to the use of agricultural products. To mitigate the PAEs risk, focusing on integrated management of the lakes, along with the implementation of stringent regulations to control the use of plasticizes in products.