Dibutyl Phthalate Research Articles

Rapid quantitative analysis of semi-volatile organic compounds in indoor surface film using direct analysis in real time mass spectrometry: a case study on phthalates

Abstract. Direct analysis in real time mass spectrometry (DART-MS) has recently emerged as a promising approach for measuring semi-volatile organic compounds (SVOCs) on indoor surface films. However, its broader application in indoor environments is limited by low measurement repeatability and no separation of isomers. Herein we developed a sampling suite of indoor surface films for DART-MS analysis, optimized settings of DART to obtain higher analytical performance, and demonstrated the possibility of separating isomeric compounds using tandem mass spectrometry (MS/MS). Two pairs of isomeric phthalate esters, including di(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) and diisobutyl phthalate (DiBP) and di-n-butyl phthalate (DnBP), were used as examples for method optimization and validation. Under optimized conditions, the instrument responses for all four compounds exhibited good linearity (r>0.992) and acceptable repeatability (intraday relative standard deviation (RSD) < 11.0 %). The limits of quantification for the four phthalate esters ranged from 0.042 to 0.24 ng cm−2. The uncertainty in the separation of isomeric components using MS/MS was < 11.4 %, which is acceptable for real sample analysis. To further assess the developed method, we analyzed 10 film samples collected side by side in an occupied office. DnOP was not detected. The RSD among samples was 6.1 % for DEHP, 4.6 % for DnBP, and 10.4 % for DiBP, indicating the overall good repeatability of the collection and measurement method developed. With improved performance, the developed method increases the feasibility of the DART-MS technique for monitoring the dynamics of chemical composition of indoor surface films.

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.

Simulation study on heavy metals, phthalate esters, and organic halogens: Content and distribution characteristics during waste paper recycling.

Imported waste paper and recycled pulp may contain pollutants, posing potential environmental risks to the ecosystem of China. This study examined the presence and distribution patterns of heavy metals, phthalate esters (PAEs), and adsorbable organic halogens (AOX) in recycled pulp and production wastewater after various recycling processes of three typical restricted types of imported waste paper. The results indicated that the concentration ranges of heavy metals, PAEs, and AOX in the three types of imported recycled waste paper were 21.61-40.38mg/kg, 15.35-27.88mg/kg, and 19.21-57.72mg/kg, respectively. The comparative analysis with the initial waste paper demonstrated a reduction in heavy metal content in the recycled pulp by 17.80-49.75%, PAEs by 65.42-90.55%, and AOX by 32.80-42.34%. The average concentrations of these pollutants in wastewater were 0.85-1.66mg/L, 27.28-59.86mg/L, and 1.15-3.34mg/L, respectively. Chromium and lead were identified as the primary heavy metals present in the waste paper. Following pulping, No. 1 and No. 2 met the arsenic and lead levels specified in the "Reuse Fiber Pulp" standard (GB/T24320-2021), whereas No. 3 met these criteria after de-inking only. The main PAEs detected in the waste paper were dibutyl phthalate and di(2-ethylhexyl) phthalate, most of which were removed during the pulping stage. Significantly higher levels of AOX were observed in No. 2 and No. 3 than in No. 1, with a minimal impact on AOX removal from the pulp during the recycling process.

Enhanced biochemical treatment of pulping wastewater by Fenton process: Water quality optimization and detoxification efficiency

Pulping wastewater, characterized by enormous quantities, high pollution load and significant biotoxicity, making its effective treatment crucial for environmental protection. This study evaluated the performance of typical (anaerobic/aerobic) and advanced oxidation (Fenton) processes in pulping wastewater treatment, in relation to physicochemical parameters, acute toxicity and organic indexes. Raw wastewater contains numerous aromatic pollutants with benzene rings and unsaturated bonds, resulted in high pollution load and acute toxicity. Typical treatment process effectively reduced various pollution parameters, with toxicity was significantly decreased or completely removed (83.57–100.00 %). The residual toxicity unit (TU) of aerobic effluent for luminousbacteria and chlorella was only 2.76 and 1.23, respectively. Specifically, acute toxicity showed significantly positively correlated with total nitrogen (TN) and total organic carbon (TOC), positively associated with UV254, while negatively related to humification index (HIX). Although Fenton process optimized wastewater quality, it generated toxic intermediates that increased luminousbacteria toxicity to 5.12 TU, and Daphnia magna toxicity from 0.33 to 0.84 TU. Notably, newly organic pollutants such as Tricosane and Dibutyl phthalate may contributed to increased toxicity. In summary, these results concluded that advanced treatment processes may introduce unexpected toxicity and emphasized the importance of evaluate biotoxicity for environment protection.

Characterization of a novel salt- and solvent-tolerant esterase Dhs82 from soil metagenome capable of hydrolyzing estrogenic phthalate esters

Esterases that can function under extreme conditions are important for industrial processing and environmental remediation. Here, we report the identification of a salt- and solvent-tolerant esterase, Dhs82, from a soil metagenomic library. Dhs82 prefers short-chain p-nitrophenyl (p-NP) esters and exhibits enzymatic activity up to 1460 ± 61 U/mg towards p-NP butyrate. Meanwhile, Dhs82 can catalyze the hydrolysis of dialkyl phthalate esters, especially the widely-used diethyl phthalate (DEP), dipropyl phthalate (DPP) and di-n-butyl phthalate (DBP). Importantly, as an acidic protein with negative charges dominating its surface, Dhs82 is highly active and extraordinarily stable at high salinity. This property is quite rare among previously reported esterases/hydrolases capable of degrading phthalate esters (PAEs). In addition, Dhs82 activity can be significantly enhanced in the presence of solvents over a concentration range of 10–30 % (v/v). Notably, Dhs82 also showed high stability towards these solvents and solvent concentrations as high as 50–60 % (v/v) are required to inactivate Dhs82. Furthermore, molecular docking revealed the key residues, including the catalytic triad (Ser156, His281, and Asp251) and the surrounding Gly84 and Gly85, involved in the interaction of Dhs82 with DBP, depicting how Dhs82 degrades PAEs as a family IV esterase. Together, these diverse properties make Dhs82 a valuable candidate for both basic research and biotechnological applications.

Detection of Organic Explosive Residues from Outdoor Detonations using Confocal Raman Microscopy

The detection of post-blast residues in the aftermath of an explosion involving organic explosives with spectroscopic techniques is challenging as, typically, no microscopically visible unreacted particles remain after the explosion. However, some low-order explosions may leave visible particles behind, as well as the presence of significant amounts of unreacted material. In this study, four authentic open-air detonations using two simulated improvised explosive devices (IEDs) containing a mixture of military explosives (TNT and RDX), and two IEDs containing smokeless powder were conducted. The various materials they contained, including plastic, wood, and metal, were swabbed and extracted with acetone to create post-blast liquid extracts. The extracts were then dried and examined using confocal Raman microscopy, alongside a 50 ppm reference mixture of smokeless powder constituents, which was created to evaluate the effects of Raman scattering within the full smokeless powder mixture. Smokeless powder constituents, such as ethyl centralite, diphenylamine, nitroglycerin, and dibutyl phthalate, were successfully identified by comparison to the reference mixture on most substrates, with the exception of the paint stick (wood) substrate. TNT/RDX was also able to be identified in the extracts, with RDX crystals being observed in some dried extracts after solvent evaporation. However, the detection of TNT/RDX in the second detonation was unsuccessful, possibly due to an explosive chain reaction that was highly efficient. No trends were seen in substrate affinity for TNT/RDX. The challenges and benefits with the developed methodology for the detection of organic explosive residues from a variety of substrates are discussed in detail.

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.

β-Cyclodextrin/Zn-Fe layered double hydroxides/graphitic carbon nitride nanomaterials based potentiometric sensor for paroxetine determination in environmental water samples.

Developing targeted and sensitive analytical techniques for drug monitoring in different specimens are of utmost importance. Herein, a first attempt was made for the determination of paroxetine (Prx+) in environmental water samples using a novel, sensitive, selective, stable, accurate and eco-friendly potentiometric sensor based on Zn-Fe layered double hydroxides/graphitic carbon nitride (Zn-Fe LDH/g-C3N4) nanomaterials with β-cyclodextrin (β-CD) as the sensing ionophore and dibutyl phthalate (DBP) as the plasticizer. The prepared nanomaterial was characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The surface properties of the proposed sensor were characterized by electrochemical impedance spectroscopy (EIS). The sensor exhibited an excellent Nernstian slope of 59.3 ± 0.7 mV decade-1 covering a wide linear working range of 1.0 × 10-6 to 1.0 × 10-2 mol L-1, low detection limit of 3.0 × 10-7 mol L-1, low quantification limit of 9.9 × 10-7 mol L-1, long life time, sufficient selectivity, high chemical and thermal stability within a wide pH range of 2.0-9.0. This analytical method was successfully implemented for Prx+ determination in a pure form, pharmaceutical formulation and different water samples.

Individual Inhalation Exposure to Phthalates and Their Associations with Anthropometric and Physiological Indices in Primary School Children in Jinan, China

Phthalates are commonly found in indoor environments. Consequently, children may be exposed to phthalates through the air, potentially causing health issues. We collected 72 air samples from 60 households and 12 classrooms in Jinan, surveyed and health-examined children, assessed their phthalate inhalation exposure, and analyzed the associations between inhalation exposure levels and children’s anthropometric and physiological indicators. Eight phthalates were detected in children’s households and classrooms, with detection frequencies ranging from 91.6% to 100%. Di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and di (2-ethylhexyl) phthalate (DEHP) were the predominant phthalates. Children’s indoor inhalation exposure to phthalates ranged from 8.90 to 147 ng/(kg·day), with DEHP being the main inhaled phthalate. The non-carcinogenic risks of indoor environments where children live are within acceptable limits. DEHP has a low carcinogenic risk. Di-n-octyl phthalate (DnOP) exposure was associated with a decrease in body mass index z-score, waist circumference, and hip circumference. Additionally, DEHP exposure was negatively associated with the waist-to-hip ratio. DiBP exposure was negatively associated with the systolic blood pressure z-score, while DnOP exposure was negatively associated with the diastolic blood pressure z-score. Furthermore, DEHP exposure was positively associated with fractional exhaled nitric oxide z-score. The findings of this study suggest that phthalate inhalation exposure may substantially affect various health metrics in children, including body mass index, waist and hip circumference, and blood pressure, and increase the risk of respiratory tract inflammation.

Environmental Stress-Induced Alterations in Embryo Developmental Morphokinetics.

The association between embryo morphokinetics and its developmental competence is well documented. For instance, early cleaved embryos are more competent in developing to blastocysts, whereas the proportion of abnormally cleaved embryos that further developed to blastocysts is low. Numerous factors, such as the parental age, lifestyle, health, and smoking habits have been reported to affect the embryo morphokinetics and, consequently, its development. However, less is known about the effect of environmental stressors on embryo morphokinetics. The current review discusses the effect of the most concerning environmental stressors on embryo morphokinetics. These stresses include heat stress and human-made chemicals such as phthalates (e.g., bis-(2-ethylhexyl phthalate, dibutyl phthalate, dimethyl phthalate, and their primary metabolites), herbicides (e.g., diaminochlorotriazine, the primary metabolite of atrazine), pharmaceutical compounds (e.g., carbamazepine, nocodazole) and pro-oxidant agents (cumene hydroperoxide, Triton X-100), as well as naturally occurring toxins such as mycotoxin (e.g., aflatoxin B1 and its metabolite, and ochratoxin A). In addition, this review discusses the effect of ionizing or non-ionizing radiation and viral infections (e.g., SARS-CoV-2, papillomavirus). Finally, it points out some potential mechanisms that underlie the impairment of embryo morphokinetics, and it suggests protective compounds, mainly the supplementation of antioxidants to improve the morphokinetics, and consequently, the embryo developmental competence.

Integrative models for environmental forecasting of phthalate migration from microplastics in aquaculture environments

The pervasive utilization of plastic tools in aquaculture introduces significant volumes of microplastic fibers, presenting a consequential risk through the leaching of additives such as phthalates. This study scrutinizes the leaching dynamics of six prevalent phthalate esters (PAEs) from thirteen plastic aquaculture tools comprising polyethylene terephthalate (PET), polypropylene (PP), and polyethylene (PE), with ΣPAEs ranging from 0.24 to 4.26 mg g−1. Di(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP) emerged as predominant, marking significant environmental concern. Over a 30-day period, leaching quantities of Σ6PAEs from PET, PP, and PE fibers reached 36.65 μg g−1, 21.87 μg g−1 and 19.11 μg g−1, respectively, influenced by factors such as time, temperature, turbulence, and salinity. Notably, turbulence exerted the most pronounced effect, followed by temperature, with negligible influence from salinity. The kinetic models aligning with interface diffusion control was developed, predicting PAEs' leaching behavior with activation energies (Ea) indicative of the process's thermodynamic nature. The application of this model to real-world aquaculture waters forecasted significant risks, corroborating with empirical data and underscoring the pressing need for regulatory and mitigation strategies against PAEs contamination from aquaculture practices.

Unravelling biochemical and molecular mechanism of a carboxylesterase from Dietzia kunjamensis IITR165 reveal novel activities against polyethylene terephthalate

Plastics and plasticizers accumulate in the ecological niches affecting biodiversity, and human and environmental health. Bacteria degrading polyethylene terephthalate (PET) were screened and PETases involved in PET degradation were characterized. Here, we identified a carboxylesterase Dkca1 of 48.44 kDa molecular mass from Dietzia kunjamensis IITR165 shown to degrade amorphous PET film into bis(2-hydroxyethyl) terephthalate (BHET) and terephthalic acid (TPA) formed 64.35 μM and 35.26 μM, respectively within 96 h at 37 °C as revealed by LC-MS analysis showed significant PET hydrolase activity similar to reported PETases. SEM analysis confirms the surface erosion as cavities and holes. Dkca1 also hydrolysed BHET and dibutyl phthalate (DBP) at a concentration of 1 mM within 3 h indicating its versatility. Fluorescence quenching shows Dkca1 protein has a maximum affinity (Kd) towards BHET (86.55 μM) than DBP (134.2 μM). The protein demonstrated high stability under temperatures above 40 °C and at the pH range of 6.0–9.0. Moreover, Amino acid composition showed that the Dkca1 enzyme belongs to family VII carboxylesterase containing conserved catalytic triad of Ser183-Glu289-His378 with pentapeptide motif GXSAG and an oxyanion hole H103GGG106, sharing 37.47 % and 32.44 % similarity with a PET hydrolase TfCa from Thermobifida fusca and PAE hydrolase CarEW from Bacillus sp. K91, respectively. A docking study revealed that ligand PET, BHET, and DBP showed favourable binding in the catalytic pocket of the Dkca1 protein.

Phthalate Esters in Water and Surface Sediments of Anambra River in Dry Season: Distribution and Human Health Risks Assessment

This study investigated phthalate ester (PAE) contamination in water and sediment samples due to their persistence and potential health risks as endocrine disruptors. Sediment analysis revealed pH ranged from 5.35 to 6.72, with total organic carbon (TOC) levels varying between 0.74% and 2.56%. Water pH values were within WHO guidelines (5.5–8.5), and turbidity levels ranged from 0.60 to 1.40 NTU. Phthalate concentrations in sediment revealed Monobutyl phthalate (MBP), Diethyl phthalate (DEP), Dipentyl phthalate (DPP), Butyl benzyl phthalate (BBP), Dibutyl phthalate (DBP), and Di(2-ethylhexyl) phthalate (DEHP). Sample SA exhibited the highest levels of MBP (0.40 mg/kg) and DEP (0.93 mg/kg). In water samples, MBP peaked at 0.01 mg/kg, while DEP reached 0.03 mg/kg, with DBP (0.07 mg/kg) and DEHP (0.08 mg/kg) also detected. Phthalate contamination in water remained below harmful thresholds. A health risk assessment calculated Chronic Daily Intake (CDI) and Hazard Quotients (HQ) for both children and adults. CDI results indicated higher risks for children, with DBP (2.20E-06 mg/kg/day) and DEHP (2.46E-06 mg/kg/day) showing the greatest concern. The HQ for children was highest for DBP (0.22), though still below the risk threshold. Adults exhibited lower CDI and HQ values, with minimal non-carcinogenic risk. These findings highlight the need for continued monitoring of phthalate pollution, especially given children’s heightened vulnerability.

Content and Health Risks of Microplastics and Phthalate Esters in Bottled Water

To study the content and health risks of microplastics （MPs） and phthalate esters （PAEs） in bottled water, a quantitative analysis of MPs was conducted by using Rose Bengal staining and stereomicroscopy. Seven PAEs were quantified by using gas chromatography-triple quadrupole tandem mass spectrometry （GC-MS/MS）. The daily intake of MPs was estimated and the carcinogenic and non-carcinogenic risks of PAEs were evaluated through a health risk assessment model. The results showed that the abundance of MPs in 21 bottled waters ranged from 48 n·L-1 to 216 n·L-1 （with the median abundance of 88 n·L-1）. The majority （72.1%） of MPs were fibrous in shape, and fragments accounted for only 27.9%. The average proportion of small-sized （10-50 μm） MPs was 33.9%, and that of large-sized MPs （>500 μm） was 4.3%. Most MPs were blue. The ∑(PAEs) in bottled water was 1.15-2.47 μg·L-1 （average 1.62 μg·L-1）. PAEs detected with high frequencies （100%） included dimethyl phthalate （DMP）, diethyl phthalate （DEP）, diisobutyl phthalate （DIBP）, di-n-butyl phthalate （DBP）, and di（2-ethylhexyl） phthalate （DEHP）, while the detection frequencies of butylbenzyl phthalate （BBP） and di-n-octyl phthalate （DNOP） were relatively low. The concentrations of DBP, DEHP, and DEP were all below the standard limits for drinking water in China. The ∑(PAEs) in the migration experiments was 0.61-2.04 μg·L-1 （average 1.33 μg·L-1）. The migration amounts of DBP and DEHP were also within the allowable range under the condition of 60℃ for 10 days. Seven PAEs were detected in both the bottles and caps, and the average content of DEHP in bottles was the highest, while DBP had the highest content in caps. The estimated intake of MPs （EDI） by drinking bottled water in different age groups of humans was 2.87 n·（kg·d）-1 for adults, 3.87 n·（kg·d）-1 for children, and 5.85 n·（kg·d）-1 for infants. The carcinogenic risks of DEHP in 21 bottled water samples and the migration test were less than the maximum acceptable risk level （1×10-6）, and the non-carcinogenic risk indices （HIs） of PAEs were all less than 1, indicating no non-carcinogenic risk to humans； however, the risk value of infants and children was higher than that of adults and should not be ignored.

Construction of Phenytoin Selective Electrodes and Its Application to Pharmaceutical Preparation

Phenytoin selective electrodes were constructed based on penytoin-phosphotungstate (Ph-PT) complex with different plasticizers; di-butyl phosphate (DBP), tri-butyl phosphate (TBP), di-butyl phthalate (DBPH),and o-nitro phenyl octyl ether (NPOE) phthalate. The electrodes based on DBPH, ONPOE plasticizers gave Narnistain slope which are, 56.4 and 55.3mV/decade with detection limit of 1.9x10-5 M , 1.8x10-5 and concentration range 10-1 to 10-4 M and pH range 3.0 – 8.0. The electrodes based on TBP and DBP showed non-Nernistain slopes, 40.2,40.5 mV/decade for both plasticizers. Interfering of some cations was investigated and shows no interfering with electrodes response. Potentiometric methods were used for measuring phenytion in pharmaceutical drugs (tablets) and the electrode based on DBPH was used for determination. The recovery obtained from measuring was in good agreements with that given in British Pharmacopeias.

Defect inhibition mechanism of 3D‐printed ceramics via synergetic resin composition and debinding processing regulation

AbstractProducing ceramic parts by Vat Photopolymerization (VPP) additive manufacture with desired mechanical properties typically requires time‐consuming debinding steps. This study aims at optimizing composition and processing parameters with the use of dibutyl phthalate (DBP) in the resin formulation and debinding in an argon atmosphere for dental zirconia‐toughed alumina (ZTA). The method produces parts with fewer defects, and 67.7% higher flexural strength while increasing the debinding heating rate over 400% compared to standard formulations debinded in air. These improvements are attributed to pore formation at low temperatures and reduced heat release and gas evolution rates arising from use of the DBP and the inert atmosphere, respectively. While ZTA ceramics were studied, this method should be applicable to many ceramic systems with exciting possibilities for promoting the rapid development of VPP 3D‐printed high‐performance ceramics for various engineering applications.

Persistent effects of di-n-butyl phthalate on liver transcriptome: impaired energy and lipid metabolic pathways

The environmental contaminant dibutyl phthalate (DBP) is reported to be hepatotoxic, but the underlying molecular pathways and pathological processes remain unclear. Here we used RNA-sequencing to characterize persistent hepatic transcriptional effects one week after the conclusion of five weeks oral exposure to 10 mg/kg/day or 100 mg/kg/day DBP in male mice. The exploratory transcriptome analysis demonstrated five differentially expressed genes (DEGs) in the 10 mg/kg/day group and thirteen in the 100 mg/kg/day group. Gene Set Enrichment Analysis (GSEA), which identifies affected biological pathways rather than focusing solely on individual genes, revealed nine significantly enriched Reactome pathways shared by both DBP treatment groups. Additionally, we found 54 upregulated and one downregulated Reactome pathways in the 10 mg/kg/day DBP group, and 29 upregulated and 13 downregulated pathways in the 100 mg/kg/day DBP group. According to the DEGs and the GSEA findings DBP exposure disrupts several key biological processes, including protein translation, protein folding, apoptosis, hedgehog signaling, degradation of extracellular matrix and alterations in the energy/lipid metabolism. Subsequent liver tissue analysis corroborated these findings, showing that DBP exposure induced tissue disorganization, oxidative stress, lipid accumulation, increased TNF-α, ATP and glucokinase levels. In addition, several proteins central for the metabolic system were affected, mostly in a dose-response pattern. Taken together the results show that DBP can cause hepatic stress and damage and suggest a potential role for DBP in the development of non-alcoholic fat liver disease, the most prevalent liver disease worldwide.

Prenatal exposure to di-n-butyl phthalate promotes RIPK1-regulated necroptosis of uroepithelial cells and induces hypospadias through the epithelial-mesenchymal transition process in newborn male rats

Maternal exposure to di-n-butyl phthalate (DBP) has been linked to the induction of hypospadias; however, the underlying mechanism remains unclear. Necroptosis is reported to be implicated in developmental malformations. This study aimed to investigate the underlying mechanism of necroptosis in the development of hypospadias. DBP was dissolved in corn oil, and pregnant rats were administered a precisely measured dose of DBP (750mg/kg/day) via gastric intubation from gestation day 14 to 18. Control rats received only corn oil. The day of birth was considered postnatal day (PND) 1. Male hypospadias rats were identified on PND 7. Genital tubercle tissues were collected and stored at −80°C for subsequent PCR analysis, cryopreserved in liquid nitrogen for western blot, or fixed in formalin for immunohistochemistry (IHC) staining. IHC staining and western blot analysis revealed increased expression of RIPK1 and necroptosis markers in genital tubercle (GT) tissue compared to the control group. Additionally, higher levels of EMT and impaired androgen receptor expression were observed in GT tissue. Exposure to increased DBP concentrations in rat primary uroepithelial cells (PUCs) led to elevated ROS production. Necroptosis markers and EMT expression levels were upregulated in PUCs following DBP incubation. Notably, treatment with DBP combined with necrostatin-1, a necroptosis inhibitor, reduced the expression of EMT markers and ROS production compared to DBP treatment alone. In vitro studies further revealed that DBP-induced necroptosis promoted the degradation of E-cadherin through the ubiquitin-proteasome pathway in PUCs. Our findings suggest that maternal exposure to DBP promotes necroptosis in uroepithelial cells by elevating ROS level and EMT status. Thus, necroptosis may play an essential role in the development of hypospadias.

Exploring the use of gull eggs as bioindicators of phthalate esters exposure

Plastic pollution and associated plasticizers are a global threat affecting aquatic environments. Phthalates are among the most used plasticizers that can impact on fauna due to their endocrine-disrupting properties. The aim of this study was to investigate the use of eggs of Audouin’s gull (Larus audouinii) and yellow-legged gull (Larus michahellis) as biomonitors of phthalate exposure. Sixteen phthalates were studied and the extraction and purification steps were optimized using various sorbents and clean-up processes to efficiently recover these contaminants in gull eggs. Analysis was performed using ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) using multiple reaction monitoring to obtain high selectivity and sensitivity. Quality control parameters and a comprehensive analysis of blank contribution are provided. The best performance was obtained with Oasis PRiME HLB cartridges with recoveries from 61 to 138% for most of the compounds. Pooled gull-egg samples from seven breeding colonies collected over the period 2016 – 2021 within the Iberian Peninsula revealed the presence of dibutoxyethyl phthalate (DBEP), hexyl 2-ethylhexyl phthalate (HEHP), dimethyl phthalate (DMP), diethyl phthalate (DEP), and dibutyl phthalate (DBP) at mean concentrations ranging from 2.27 to 1330 ng/g ww in Audouin's gull and from 2.74 to 487 ng/g ww in yellow-legged gull (DBP not detected). The absence of other phthalates is likely attributable to their metabolism and excretion by female adults. Overall, this study provides an accurate method to analyse phthalates in gull eggs and supports their use as bioindicators of phthalate contamination.

Highly efficient adsorption and removal of phthalate esters by polymers of intrinsic microporosity

In recent years, phthalate esters (PAEs) have been found to be endocrine disruptors that pose a serious safety threat to human health. Currently, adsorption is one of the most efficient technologies to remove PAEs, and the development of adsorbent materials that combine high adsorption capacity and short equilibrium time is a challenging problem. In this study, PIM-1, a typical representative of polymers of intrinsic microporosity (PIMs), was prepared through three methods and first used as adsorbents for PAEs removal. PIM-1 prepared under high temperature (HT-PIM-1) exhibited a high capacity of 787mg/g for dibutyl phthalate (DBP), a prevalent PAE in water, which is significantly higher than most reported adsorbents. Furthermore, more than 90.0% of the equilibrium adsorption capacity can be reached within 30mins. In addition, the adsorption of DBP could be inhibited by ethanol due to the enhanced interaction between DBP and ethanol, which could be revealed by molecular simulation. The adsorption mechanism of PAEs on PIM-1 mainly included hydrophobic interactions, π-π interactions, together with the size matching between PAEs and hierarchical pores of PIM-1. This study provides an idea for the application of PIMs for PAEs removal with high adsorption capacity and high efficiency. Environmental ImplicationPhthalate esters (PAEs) are emerging pollutants that pose a significant threat to public health and safety. They have been detected not only in environmental water but also in alcoholic beverages. Adsorption is widely preferred for removing PAEs, and the adsorption of PAEs in alcoholic solutions is a more challenging process compared to pure water. In this study, PIM-1 with o-phenyl groups similar to PAEs were first used as adsorbents for PAEs and demonstrated a remarkable adsorption capacity in both water (787mg/g) and alcoholic solutions (398mg/g) within a short period, surpassing the performance of commercial adsorbents.