Search Results (153)

Ziegler-Natta (Z-N) catalysts for propylene polymerization were prepared in situ using dibutyl phthalate (DNBP) or 9,9-bis(methoxymethyl)fluorene (BMMF) as internal electron donors (IDs) by treating the support precursors (Mg(OEt)₂ or MgCl₂·2.5EtOH) or MgCl₂ complex solutions with TiCl₄ respectively. In this study, eight Z-N catalysts containing two types of IDs were prepared via different preparation routes and systematically characterized with modern analytical techniques. The results indicated that, even with the same IDs, the catalysts prepared by different methods exhibited significant differences in chemical composition, particle size distribution, catalytic activity and stereoselectivity. The properties of polypropylene (PP) were largely influenced by the preparation route of the catalysts. Particularly, the catalysts obtained by the reprecipitation method showed the highest catalytic activity and the smallest MgCl₂ particle size. The distribution of stereoselective active centers in the catalysts was simultaneously affected by the preparation method and the type of IDs. In addition, the melting point (T_m) of PP could be used as an effective indicator to evaluate the relative content of the highly isotactic active centers in the catalysts. This study provides valuable insights into the rational design of Z-N catalysts for propylene polymerization, highlighting the critical role of the preparation methodology in tailoring the catalyst properties and active center distribution. Full article

Despite its advantages, 3D printing may expose users to volatile organic compounds (VOCs) and particle emissions. Emissions from commercially available acrylonitrile-butadiene-styrene (ABS)- and polyethylene terephthalate glycol (PET-G)-based filaments were analyzed to evaluate differences among material formulations from multiple manufacturers. Chamber-based measurements and complementary thermal decomposition experiments were used to characterize particle number concentrations and chemical emissions. The highest particle emissions occurred during the initial warm-up and the final stages of the printing process. The ABS-based filaments tested in this study exhibited higher VOC emissions, dominated by styrene (up to 264.75 μg/m³), and particle number concentrations approximately one order of magnitude greater than those measured for the tested PET-G-based filaments. The dominant particle sizes ranged from 55 to 90 nm. PET-G-based filaments showed higher thermal stability but emitted notable concentrations of acetaldehyde (up to 70.93 μg/m³) and phthalic acid esters. Both filament types released compounds of potential health concern, including formaldehyde and reprotoxic substances such as dibutyl phthalate and bis(2-ethylhexyl) phthalate. Differences were observed among fibers made from the same polymer type, indicating the influence of formulation-specific factors. These results underscore the importance of material selection and adequate ventilation to minimize exposure during 3D printing. Full article

This study investigated the characteristics and interrelationships of polycyclic aromatic hydrocarbons (PAHs), phthalate esters (PAEs), and microbial communities in coastal river sediments and benthic mollusks collected from an e-waste recycling area in Taizhou, Zhejiang Province. In sediments, 16 PAHs and six PAEs were detected, with concentrations ranging from 2.66 to 379.99 μg/kg and 76.5 to 3426.57 μg/kg, respectively. Four-ring PAHs (particularly fluoranthene and pyrene) and Bis(2-ethylhexyl) phthalate (DEHP) were dominant, with DEHP posing a potential risk, especially at site 10, warranting further attention. In contrast, only eight PAHs and four PAEs were detected in mollusks, with concentrations of 60.14–523.10 μg/kg and 144.55–3005.71 μg/kg, respectively. Two-ring PAHs (particularly naphthalene) and Dibutyl phthalate (DBP) were dominant, likely derived directly from the overlying water. The PAHs in sediments primarily originated from fossil fuel combustion, biomass burning, and coal combustion, while PAEs were likely derived from the release of plastic waste from solid waste recycling. Lower concentrations and fewer PAH and PAE species were observed in the sediments near the ocean and at greater distances from the e-waste recycling sites. Significant differences were observed in microbial communities between sediment and mollusk samples. Dominant phyla shared by both sample types include proteobacteria, bacteroidetes, firmicutes, and acidobacteria. The concentration of low-ring PAHs was correlated with the microbial communities, particularly in mollusk samples. Relationships were also identified between microbial communities and DEHP concentrations in sediments or DBP concentrations in mollusks. Full article

Background: Bacopa procumbens is a plant species with medicinal properties. Although several of these properties have already been validated, its use for treating pain remains untested. Objective: the objective was therefore to test the antinociceptive effect of two extracts (n-hexane and hydroalcoholic) and two fractions (aqueous and organic) from the most active extract, as well as to determine the chemical profile of Bacopa procumbens. Methods: analgesic activity was determined by antinociceptive activity using the formalin model in mice. Compounds were identified by high-performance liquid chromatography and gas chromatography coupled with mass spectrometry. Compared to the vehicle treatment (3% Tween 20), licking time was 22.8 s and 141.6 s lower when treated with the hexane extract (200 mg/kg); 43.4 s and 152.5 s with the hydroalcoholic extract (200 mg/kg); 27.2 s and 169 s with the organic fraction; and 5.4 s and 32 s difference with the positive control, in phases 1 and 2, respectively. Phytochemical analysis of the hexane extract allowed us to identify 2-pentadecanone, 6,10,14-trimetil- (11.70%), 6,10,14-trimethyl-, dibutyl phthalate (34.71%), and hexane-dioic acid bis(2-ethylhexyl) ester (45.15%). Conclusions: We identified arbutin (1), 5-(p-hydroxybenzoyl) shikimic acid (2), and procumgastrodin A (3) in the BpFo fraction. In conclusion, we demonstrated that the BpH extract and the BpFo fraction have anti-nociceptive properties that may be associated with compounds 2 and 3. Full article

Phthalates (PAEs), non-phthalate plasticizers (NPPs) and bisphenols (BPs) were monitored by fully validated GC-MS and HPLC-MS/MS protocols in honeys from diverse Algerian coastal and non-coastal areas. Experimental results showed that no honey was free of these compounds. A higher PAE contamination was evident in coastal honeys, while NPPs were more abundant in non-coastal samples. The revealed PAEs were: dimethyl phthalate (DMP, 28.12–277.14 µg/kg), diethyl phthalate (DEP, 18.20–404.70 µg/kg), dibutyl phthalate (DBP, 29.58–889.71 µg/kg) and bis(2-ethylhexyl) phthalate (DEHP, 20.66–523.16 µg/kg), while bis(2-ethylhexyl) terephthalate (DEHT, 8.95–206.12 µg/kg) and diethyl adipate (DEA, 10.36–97.51 µg/kg) were the NPPs determined. The EU—not Algeria—classifies DBP and DEHP as very high concern substances. Nonetheless, these PAEs were the most abundant and frequently detected contaminants. Even certain honeys showed DEHP outliers compared to the range provided above (1256.53 µg/kg). Coastal and non-coastal honeys were contaminated by bisphenol A (BPA, 2.64–12.73 µg/kg), thus, raising compliance concerns for export in the EU. In fact, the assessment of dietary exposure and toxicological risk derived from the consumption of these honeys highlighted that, while the exposure to plasticizers was within the safety limits, the exposure to BPA raised toxicological concern. Hopefully, these findings will support the constant monitoring of beekeeping activities and products and encourage the adoption of good practices with a view to guide the advancement of the sector and better safeguard consumers. Full article

Plastic pollutants, including phthalates, bisphenol A (BPA), per- and polyfluoroalkyl substances (PFAS), and microplastics (MPs), are increasingly recognized as emerging environmental cofactors that intersect with infectious disease dynamics. These compounds, once considered inert, can alter immune function, reshape host–pathogen interactions, and directly influence viral survival and transmission. In this review, we compile current evidence on the chemistry, environmental occurrence, and biological activity of major plastic-associated pollutants with emphasis on their role in viral infections. Phthalates such as di(2-ethylhexyl) phthalate (DEHP) and its metabolite MEHP modulate innate immune signaling and have been shown to exacerbate infections, including Dengue and Coxsackievirus B3. Other DEHP-like phthalates, such as dibutyl phthalate (DBP), exhibit consistent infection-enhancing effects, while high molecular weight or cyclical phthalates such as polyvinyl acetate phthalate (PVAP) display conflicting results in their modulation of viral infections. BPA, widely detected in human tissues, acts through endocrine and immune disruption, worsening viral myocarditis, and altering influenza outcomes. PFAS, persistent “forever chemicals,” reshape adaptive immune responses and are associated with increased susceptibility, viral persistence, or severity of infection of herpesvirus (HCMV, EBV, HSV-1), hepatitis virus, and influenza infection. Microplastics represent a distinct risk by acting as physical carriers for viruses and bacteria, stabilizing viral RNA, enhancing host cell uptake, and skewing immune responses. Together, these pollutants extend beyond toxicology into virology, providing novel insights into how environmental exposures converge with viral pathogenesis. We highlight mechanistic advances and critical knowledge gaps and propose future directions for integrating environmental health and infectious disease research. Full article

Solar energy, as a clean and renewable resource, plays a pivotal role in advancing sustainable energy technologies. The efficiency of front-side silver paste is critical for the photovoltaic performance of Tunnel Oxide Passivated Contact (TOPCon) solar cells. In this study, we comprehensively investigated how the composition of organic vehicles in conductive pastes influences both printing rheological properties and electrical performance. Through rheological characterization, contact angle measurements, and Three-Interval Thixotropy Tests (3ITT), we examined the effects of varying solvent, binder, and thixotropic agent ratios on paste properties. The optimized formulation—a solvent mixture of lauryl alcohol ester (TE), butyl carbitol (DGME), butyl carbitol acetate (BCA), and dibutyl phthalate (DBP) in a 3:4:2:1 ratio, with ethyl cellulose (EC) STD10 as the binder and a polyamide wax (PAW)–hydrogenated castor oil (HCO) thixotropic agent at a 3:1 mass ratio—demonstrated superior viscosity control and rapid structural recovery. Printed grid lines achieved a height-to-width ratio (H/W) of 0.35 and a sheet resistance (Rs) of 1.43 Ω/□. These findings reveal direct relationships between organic vehicle composition, paste rheology, and functional performance, providing practical guidance for the design and optimization of high-performance conductive pastes for c-Si solar cells. This work establishes a foundation for improving both the efficiency and reliability of next-generation silver paste formulations in photovoltaic applications. Full article

Environmental pollutants are persistent chemicals that pose substantial risks to human health, contributing to global mortality and economic burden. In real-world situations, exposure rarely occurs to single compounds; instead, people are chronically exposed to complex mixtures at low concentrations. However, most regulatory frameworks still rely on single-substance risk assessments, potentially underestimating the hazards associated with combined exposures. This study investigated the cytotoxic interactions of binary mixtures of five environmentally relevant pollutants: bisphenol A (BPA), bisphenol A diglycidyl ether (BADGE), dibutyl phthalate (DBP), di(2-ethylhexyl) phthalate (DEHP), and perfluorooctanoic acid (PFOA), using the human lymphoblast cell line NALM-6. Cells were exposed for 72 h to each compound individually and to all possible binary combinations, reflecting concentrations reported in human plasma or serum. Cell viability was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and interactions were analyzed using the Bliss model of independence and two-way analysis of variance (ANOVA). Intracellular reactive oxygen species were measured using the 2′,7′-dichlorodihydrofluorescein diacetate (DCFH-DA) probe to explore the involvement of oxidative stress. Synergistic interactions were observed under specific conditions, although not all statistically identified interactions corresponded to biologically significant effects. The BPA-DBP combination produced the highest cytotoxicity when both pollutants were present at 100 nM (31%), consistent with a strong synergistic effect. A similar pattern was observed for BADGE-BPA. ROS production was partially associated with cytotoxicity in these selected mixtures. Overall, these findings highlight the importance of distinguishing statistical synergy from toxicological relevance. Full article

(1) Background: Hot pot bases are susceptible to phthalate (PAE) contamination due to their high lipid content. Standard risk models often fail to capture extreme values, leading to biased exposure estimates. This study characterized dibutyl phthalate (DBP) and bis(2-ethylhexyl) phthalate (DEHP) contamination using a hybrid modeling framework to ensure precise risk profiling. (2) Methods: A total of 91 samples were analyzed via GC-MS. Concentration data were fitted using traditional parametric, extreme value mixture (EVMM), and finite mixture models. Probabilistic dietary risks were assessed for Chinese demographic groups using 10,000-iteration Monte Carlo simulations. (3) Results: DEHP (detection rate: 55%) and DBP (32%) were best modeled by a two-component Gamma mixture and a Lognormal–Generalized Pareto distribution, respectively. These advanced models significantly outperformed conventional distributions in capturing upper-tail extremes. Crucially, all hazard quotients (HQs) remained below the safety threshold of 1, indicating acceptable risk, although children aged 7–13 exhibited the highest calculated risk (Max DEHP HQ = 0.68). (4) Conclusions: Although current exposure levels are within safe limits, the heavy-tailed distributions identify potential sporadic high-exposure events that traditional models overlook, specifically highlighting the relative vulnerability of children aged 7–13. This study validates that hybrid statistical approaches offer superior precision for analyzing skewed contamination data. Consequently, these findings provide a critical scientific basis for refining regulatory monitoring and implementing targeted source-tracking measures to mitigate long-tail food safety risks. Full article

Microplastics (MPs) and their chemical leachates are increasingly detected in landfill leachate, raising concerns about impacts on biological nitrogen removal. This study examined the effects of low-density polyethylene (LDPE) and polypropylene (PP) MPs on anaerobic ammonium oxidation (anammox) performance using suspended, attached, and granular biomass. The results showed that exposure to LDPE and PP MPs did not significantly inhibit specific anammox activity (SAA) across all anammox biomass types. However, the leachates of LDPE and PP MPs under relevant EU migration testing guidelines could cause transient inhibition. Non-targeted GC-MS analysis identified 31 and 37 leachable compounds from LDPE and PP, including the toxic plasticizer dibutyl phthalate (DBP). DBP caused concentration-dependent but transient inhibition of nitrogen removal in granular biomass, peaking at 29.4% after 5 h at 100 mg/L, with full recovery within 24 h. Higher DBP retention was observed in granular and attached growth biomass compared to suspended growth biomass. Crucially, complex biomass structures buffer these effects, emphasizing the need to assess both physical and chemical MP aspects in wastewater systems. Consequently, attached growth and granular systems are recommended over suspended growth configurations for leachate treatment, owing to their superior resilience to toxic shock and enhanced retention capabilities. Full article

This study produces high-purity nano-silica from corn straw ash (biomass power plants) using an alkaline fusion-derived sodium silicate solution. CO₂ replaces traditional acids in the carbonation reaction, enabling high extraction yield (93.11%). The process addresses the gap in directly utilizing combustion ash for such high-purity silica. Key optimal conditions identified were 5 M aq. HCl concentration, NaOH fusion reagent, 1:1.2 mixing ratio, 3 M aq. NaOH solvent, and 12 h ripening. The resulting nano-silica achieved 92.73% purity, 10–50 nm particle size, 270 × 10⁻⁵ m³/kg dibutyl phthalate (DBP) absorption, 55.9916 m²/g specific surface area, 6.38% loss on drying (LOD), and 6.69% loss on ignition (LOI). These properties meet national standards for premium, loosely structured nano-silica. This method provides an economical and effective silicon source, reducing costs and offering economic-environmental benefits. Full article

Cnidium monnieri is a valuable functional plant with significant potential for green pest control. However, its large-scale application is limited by its low and uneven seed germination in fields. To determine the factors that affect the germination of C. monnieri seeds, we examined its seed viability, germination percentage and germination speed index (GSI) after seed-coat treatments, water permeability, and the types and activity of endogenous inhibitory substances in C. monnieri seeds. The results indicated that the seed viability of C. monnieri is 95%, but the germination percentage was relatively low (12.60%). Seed coat removal significantly enhanced both the germination percentage and the GSI, but had no significant effect on water absorption rate. Moreover, ethyl acetate extracts completely inhibited the seed germination of the control non-dormant Brassica rapa subsp. rapa, while diethyl ether extracts showed moderate suppression, and petroleum ether extracts exhibited the weakest effect. And the three endogenous inhibitory substances, i.e., dibutyl phthalate, 2,6-di-tert-butylphenol, and 2,4-di-tert-butylphenol significantly reduced the seed germination, seedling height and root length of B. rapa, indicating their high inhibitory efficiency on seed germination. Our study demonstrates that the mechanical barrier of the seed coat and the presence of potent endogenous germination inhibitory substances are the key factors influencing the germination of C. monnieri seeds. These findings provide a theoretical basis for promoting seed germination of C. monnieri, which enhance its application value as functional plant for green pest control. Full article

Microplastics harbor chemical additives and absorb pollutants from the environment. Microplastics pose a human health threat and have been found in nearly all human tissues. The toxicological pathways and physiological effects of microplastic-mediated chemical exposure following ingestion remain unknown. Here we use Caenorhabditis elegans to investigate the effects of di-butyl phthalate and polystyrene microplastic mixtures on fertility and lifespan. Our studies demonstrate that 1 µm microplastics at 1 mg/L exposure levels result in decreased brood size, whereas 1000 times fewer microplastics (1 µg/L) did not affect the number of eggs laid. While there was no change in brood size at 1 µg/L microplastic exposure levels, there was an increase in embryonic lethality. Microplastics-mediated delivery of di-butyl phthalate to C. elegans significantly reduced brood size and increased embryonic lethality compared to exposure to microplastics alone. This reproductive toxicity is potentially due to a stress response via DAF-16, as observed with microplastics and di-butyl phthalate co-exposure. Furthermore, chronic exposure (from hatching onward) to microplastics shortened the lifespan of C. elegans, which was further reduced with di-butyl phthalate co-exposure. The exacerbated defects observed with co-exposure to phthalate-containing microplastics underscore the risks associated with microplastics releasing the additives and/or chemicals that they have absorbed from the environment. Full article

Covered stents have made a significant contribution to managing coronary artery perforation (CAP). Biocompatibility and toughness are critical properties for the covering membrane of covered stents. The mismatch between covered stents and patient coronary arteries in the clinic restricts the application of covered stents for emergency CAP. The ability to rapidly in situ coating of the stent at the rescue scene has so far been elusive, especially for small-diameter coronary artery covered stents. Here, we investigate a rapid coating technology of covered stents with polyvinylidene fluoride (PVDF)/dibutyl phthalate (DBP) covering membrane for CAP. The highly tough membrane and the short coating timeframe make it possible to prepare the covered stent suitable for patients with emergency CAP. In vitro cell assays demonstrated the excellent biocompatibility of the covering membrane. Moreover, in vivo evaluation in a rabbit model demonstrated successful delivery of the covered stent through the sheath system and effective sealing of vascular perforation. Full article

The growing importance of sustainable technologies and environmental safety is promoting the implementation of green chemistry principles in the field of energetic materials. Traditionally, nitrocellulose-based propellants are plasticized with dibutyl phthalate (DBP), which is classified as a hazardous substance due to its toxicity and migration during storage. In this work, triethyl 2-acetylcitrate (ATEC) and tributyl 2-acetylcitrate (ATBC) were investigated as biodegradable and non-toxic alternatives to DBP. The objective of this study was to evaluate the thermal and chemical stability, physicochemical properties, and incorporation efficiency of these eco-friendly plasticizers in regard to propellants prepared from nitrocellulose of different origins and with nitrogen contents. The stability of the obtained propellants was assessed based on accelerated aging tests conducted in accordance with NATO STANAG 4582 and AOP-48 procedures. The results showed that both the ATEC- and ATBC-modified propellants meet the stability requirements corresponding to at least ten years of storage at 25 °C. The modified propellants showed slightly lower heats of combustion. Both plasticizers were effectively integrated into the nitrocellulose matrix without compromising density or stability. This study confirms that citric-acid-based plasticizers are promising green alternatives to conventional phthalates, offering improved environmental compatibility while maintaining the required performance and safety of nitrocellulose propellants. Full article