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1.
J Environ Sci (China) ; 147: 282-293, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39003047

RESUMO

There have been reports of potential health risks for people from hydrophobic organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated hydrocarbons (PCHs), and organophosphate flame retardants (OPFRs). When a contaminated site is used for residential housing or public utility and recreation areas, the soil-bound organic pollutants might pose a threat to human health. In this study, we investigated the contamination profiles and potential risks to human health of 15 PAHs, 6 PCHs, and 12 OPFRs in soils from four contaminated sites in China. We used an in vitro method to determine the oral bioaccessibility of soil pollutants. Total PAHs were found at concentrations ranging from 26.4 ng/g to 987 ng/g. PCHs (0.27‒14.3 ng/g) and OPFRs (6.30‒310 ng/g) were detected, but at low levels compared to earlier reports. The levels of PAHs, PCHs, and OPFRs released from contaminated soils into simulated gastrointestinal fluids ranged from 1.74% to 91.0%, 2.51% to 39.6%, and 1.37% to 96.9%, respectively. Based on both spiked and unspiked samples, we found that the oral bioaccessibility of pollutants was correlated with their logKow and molecular weight, and the total organic carbon content and pH of soils. PAHs in 13 out of 38 contaminated soil samples posed potential high risks to children. When considering oral bioaccessibility, nine soils still posed potential risks, while the risks in the remaining soils became negligible. The contribution of this paper is that it corrects the health risk of soil-bound organic pollutants by detecting bioaccessibility in actual soils from different contaminated sites.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Solo , Poluentes do Solo/análise , China , Medição de Risco , Hidrocarbonetos Policíclicos Aromáticos/análise , Humanos , Solo/química , Interações Hidrofóbicas e Hidrofílicas , Retardadores de Chama/análise , Hidrocarbonetos Clorados/análise
2.
J Environ Sci (China) ; 147: 93-100, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39003087

RESUMO

Polybromodiphenyl ethers (PBDEs), the widely used flame retardants, are common contaminants in surface soils at e-waste recycling sites. The association of PBDEs with soil colloids has been observed, indicating the potential risk to groundwater due to colloid-facilitated transport. However, the extent to which soil colloids may enhance the spreading of PBDEs in groundwater is largely unknown. Herein, we report the co-transport of decabromodiphenyl ester (BDE-209) and soil colloids in saturated porous media. The colloids released from a soil sample collected at an e-waste recycling site in Tianjin, China, contain high concentration of PBDEs, with BDE-209 being the most abundant conger (320 ± 30 mg/kg). The colloids exhibit relatively high mobility in saturated sand columns, under conditions commonly observed in groundwater environments. Notably, under all the tested conditions (i.e., varying flow velocity, pH, ionic species and ionic strength), the mass of eluted BDE-209 correlates linearly with that of eluted soil colloids, even though the mobility of the colloids varies markedly depending on the specific hydrodynamic and solution chemistry conditions involved. Additionally, the mass of BDE-209 retained in the columns also correlates strongly with the mass of retained colloids. Apparently, the PBDEs remain bound to soil colloids during transport in porous media. Findings in this study indicate that soil colloids may significantly promote the transport of PBDEs in groundwater by serving as an effective carrier. This might be the reason why the highly insoluble and adsorptive PBDEs are found in groundwater at some PBDE-contaminated sites.


Assuntos
Coloides , Retardadores de Chama , Água Subterrânea , Éteres Difenil Halogenados , Poluentes do Solo , Solo , Poluentes Químicos da Água , Éteres Difenil Halogenados/análise , Coloides/química , Água Subterrânea/química , Poluentes do Solo/análise , Poluentes do Solo/química , Solo/química , Poluentes Químicos da Água/análise , China , Retardadores de Chama/análise , Monitoramento Ambiental , Modelos Químicos
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(6): 847-856, 2024 Jun 06.
Artigo em Chinês | MEDLINE | ID: mdl-38955732

RESUMO

Objective: To explore the impact of whole blood organophosphate esters (OPEs) flame retardant exposure on thyroid function-related hormones in healthy older adults. Methods: In this panel study, five repeated population-based epidemiological surveys and biological sample collection were conducted from September 2018 to January 2019, with 76 healthy older adults aged 60-69 years in the Dianliu Community of Jinan, Shandong Province. Information on the sociodemographic characteristics, diet, and health status of the respondents was systematically gathered through questionnaires and physical examinations. Fasting venous blood was collected to determine the levels of OPEs, thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4). A linear mixed-effects model was used to analyze the impact of OPEs exposure on thyroid function-related hormones in healthy older adults. Results: Each of the 76 subjects participated in at least two follow-up visits, resulting in a total of 350 person visits. The age of the study participants was (65.07±2.76) years, with 38 participants of both sexes. A total of eight OPEs were included with a detection rate exceeding 50%, and the M (Q1, Q3) for ∑OPEs was 3.85 (2.33, 5.74) ng/ml, with alkyl-OPEs being the major type of OPEs with an M (Q1, Q3) of 1.27 (0.64, 2.50) ng/ml. The M (Q1, Q3) for TSH, T3, and T4 was 3.74 (2.55, 5.69) µIU/ml, 1.32 (1.10, 1.60) ng/ml, and 45.04 (36.96, 53.27) ng/ml, respectively. Linear mixed-effects model showed that TSH was significantly decreased by 9.93% (95%CI:-15.17%, -4.36%) and 11.14% (95%CI:-15.94%, -6.06%) in older adults for each quartile level increase in TnBP and TEHP exposures, respectively. Gender-stratified analysis indicated that TEHP exposure was negatively associated with TSH levels in male older adults, whereas a decrease in TSH levels among female older adults was associated with TnBP exposure. Conclusion: Exposure to whole blood OPEs is associated with decreased TSH levels among healthy older adults, with notable gender differences.


Assuntos
Ésteres , Retardadores de Chama , Organofosfatos , Tireotropina , Tiroxina , Humanos , Idoso , Pessoa de Meia-Idade , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Exposição Ambiental/efeitos adversos , Hormônios Tireóideos/sangue , Masculino , Feminino , Inquéritos e Questionários , Glândula Tireoide/efeitos dos fármacos
4.
Artigo em Chinês | MEDLINE | ID: mdl-38964913

RESUMO

Brominated flame retardants (BFRs) are a kind of brominated compounds widely used in electronic and electrical appliances, textiles, construction materials and other industrial products to improve the flame retardant property. Because of its strong chemical stability, environmental persistence, long-distance transmission, biological accumulation, the exposure of humans and organisms in the ecosystem is increasing, and its potential biological effects are of great concern. Now BFRs can be detected in breast milk, serum, placenta and cord blood. Studies have shown that exposure to BFRs during pregnancy can lead to adverse birth outcomes such as low birth weight, malformation, gestational age changes and impairment of neurobehavioral development. This article summarizes the pollution and population exposure of three traditional BFRs, polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), and tetrabromobisphenol A (TBBPA), as well as the impact and mechanism of prenatal exposure on offspring birth outcomes and growth and development. It explores the harm of prenatal exposure to BFRs to offspring and proposes preventive measures for occupational populations for reference.


Assuntos
Retardadores de Chama , Éteres Difenil Halogenados , Hidrocarbonetos Bromados , Exposição Materna , Bifenil Polibromatos , Efeitos Tardios da Exposição Pré-Natal , Retardadores de Chama/toxicidade , Gravidez , Humanos , Feminino , Hidrocarbonetos Bromados/toxicidade , Éteres Difenil Halogenados/toxicidade , Exposição Materna/efeitos adversos , Bifenil Polibromatos/toxicidade
5.
Environ Health Perspect ; 132(7): 77001, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38968089

RESUMO

BACKGROUND: Organophosphate esters (OPEs), used ubiquitously as flame retardants and plasticizers in consumer products, are suspected of having developmental toxicity. OBJECTIVES: Our study aimed to estimate associations between prenatal exposure to OPEs and fetal growth, including both ultrasound (head circumference, abdominal circumference, femur length, and estimated fetal weight) and delivery [birth weight z-score, small-for-gestational age (SGA), and large-for-gestational age (LGA)] measures of growth. METHODS: In the LIFECODES Fetal Growth Study (2008-2018), an enriched case-cohort of 900 babies born at the small and large ends of the growth spectrum, we quantified OPE biomarkers in three urine samples per pregnant participant and abstracted ultrasound and delivery measures of fetal growth from medical records. We estimated associations between pregnancy-averaged log-transformed OPE biomarkers and repeated ultrasound measures of fetal growth using linear mixed-effects models, and delivery measures of fetal growth using linear (birth weight) and logistic (SGA and LGA) regression models. RESULTS: Most OPE biomarkers were positively associated with at least one ultrasound measure of fetal growth, but associations with delivery measures were largely null. For example, an interquartile range (IQR; 1.31 ng/mL) increase in bis(2-chloroethyl) phosphate concentration was associated with larger z-scores in head circumference [mean difference (difference): 0.09; 95% confidence interval (CI): 0.01, 0.17], abdominal circumference (difference: 0.10; 95% CI: 0.02, 0.18), femur length (difference: 0.11; 95% CI: 0.03, 0.19), and estimated fetal weight (difference: 0.13; 95% CI: 0.04, 0.22) but not birth weight (difference: 0.04; 95% CI: -0.08, 0.17). At delivery, an IQR (1.00 ng/mL) increase in diphenyl phosphate (DPHP) concentration was associated with an SGA birth (odds ratio: 1.46; 95% CI: 1.10, 1.94). CONCLUSIONS: In a large prospective cohort, gestational OPE exposures were associated with larger fetal size during pregnancy, but associations at delivery were null. DPHP concentrations were associated with heightened risk of an SGA birth. These findings suggest that OPE exposure may affect fetal development. https://doi.org/10.1289/EHP14647.


Assuntos
Desenvolvimento Fetal , Retardadores de Chama , Exposição Materna , Plastificantes , Humanos , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Plastificantes/toxicidade , Gravidez , Exposição Materna/estatística & dados numéricos , Organofosfatos , Adulto , Peso ao Nascer/efeitos dos fármacos , Recém-Nascido , Ésteres , Biomarcadores/urina , Estudos de Coortes , Masculino
6.
Environ Health ; 23(1): 64, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003460

RESUMO

BACKGROUND: Brominated Flame Retardants (BFRs) have attracted widespread concern due to their environmental persistence and potential toxicity. This study aims to examine the association between BFRs exposure and hypertension. METHODS: We used data from the National Health and Nutrition Examination Survey (NHANES) spanning 2005 to 2016 for the cross-sectional analysis. To evaluate the individual and combined impacts of BFRs exposure on hypertension, we utilized multivariate models, including generalized additive models, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) models. RESULTS: 9882 individuals (48% male) aged ≥ 20 were included in the final analysis, of whom 4114 had hypertension. After controlling for potential covariates, higher serum concentrations of PBDE100 (OR: 1.26; 95% CI: 1.01, 1.57) and PBDE153 (OR: 1.50; 95% CI: 1.18, 1.88) were significantly associated with hypertension. A nonlinear relationship between PBDE28 and hypertension was observed (P = 0.03). Moreover, BFRs mixture were positively associated with the prevalence of hypertension in both the WQS (ß:1.09; 95% CI: 1.02, 1.17; P = 0.02) and BKMR models. CONCLUSION: Our study suggested that BFRs exposure is positively associated with hypertension in the general population. To confirm this association and elucidate the mechanisms, further research is required.


Assuntos
Exposição Ambiental , Poluentes Ambientais , Retardadores de Chama , Éteres Difenil Halogenados , Hipertensão , Inquéritos Nutricionais , Humanos , Retardadores de Chama/análise , Feminino , Masculino , Hipertensão/epidemiologia , Hipertensão/induzido quimicamente , Adulto , Pessoa de Meia-Idade , Éteres Difenil Halogenados/sangue , Estudos Transversais , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/sangue , Estados Unidos/epidemiologia , Adulto Jovem , Idoso , Bifenil Polibromatos/sangue
7.
Ecotoxicol Environ Saf ; 281: 116674, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38964056

RESUMO

The persistence of the novel brominated flame retardant, bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (TBPH), in the environment and its potential for bioaccumulation in living organisms, including humans, further exacerbate its health risks. Therefore, ongoing research is crucial for fully understanding the extent of TBPH's neurotoxicity and for developing effective mitigation strategies. This study aims to investigate the potential neurotoxicity of TBPH on mouse neurobehavior and to evaluate the protective effects of the natural antioxidant astaxanthin (AST) against TBPH-induced neurotoxicity. The results indicate that exposure to TBPH can lead to a decline in learning and memory abilities and abnormal behaviors in mice, which may be associated with oxidative stress responses and apoptosis in the hippocampus. TBPH may disrupt the normal function of hippocampal neurons by activating the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway. Mice exposed to TBPH treated with AST showed improved learning and memory abilities in the Morris water maze (MWM) and Step-down test (SDT). AST, through its antioxidant action, was able to significantly reduce the increase in reactive oxygen species (ROS) levels induced by TBPH, the increased expression of apoptosis markers, and the activation of the ERK1/2-FOS signaling pathway, alleviating TBPH-induced apoptosis in hippocampal neurons and improving neurobehavioral outcomes. These findings suggest that AST may alleviate the neurotoxicity of TBPH by modulating molecular events related to apoptosis and the ERK1/2-FOS signaling pathway. Thus, this study provides evidence for AST as a potential interventional strategy for the prevention or treatment of cognitive decline associated with environmental neurotoxicant exposure.


Assuntos
Hipocampo , Sistema de Sinalização das MAP Quinases , Espécies Reativas de Oxigênio , Xantofilas , Animais , Xantofilas/farmacologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Hipocampo/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Comportamento Animal/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Retardadores de Chama/toxicidade , Antioxidantes/farmacologia , Ácidos Ftálicos/toxicidade , Apoptose/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos
8.
J Environ Manage ; 364: 121362, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878568

RESUMO

Hazardous substances in demolition waste are often deemed a barrier to a circular economy owing to concerns about their fate in recycled materials. However, with the growing demand for recycling materials, it is essential to find circular solutions for construction materials but still protect health and the environment by managing hazardous substances. In this study, selected hazardous substance groups were analysed from demolition waste samples. Most of the concentrations did not raise any concerns when the safety of recycling materials was considered. However, the detection limits of laboratory chemical analysis can be discussed, as bromine was found in samples by an X-ray fluorescence (XRF)-analyser, but only one laboratory detected brominated flame retardants (BRFs). New technologies and practices are needed to follow the chemical content of materials used in the construction phase. Detecting hazardous substances in recyclable materials is the only way to achieve harmless material cycles.


Assuntos
Materiais de Construção , Retardadores de Chama , Substâncias Perigosas , Reciclagem , Substâncias Perigosas/análise , Retardadores de Chama/análise , Materiais de Construção/análise
9.
Molecules ; 29(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38893541

RESUMO

Ammonium polyphosphate (APP), a pivotal constituent within environmentally friendly flame retardants, exhibits notable decomposition susceptibility and potentially engenders ecological peril. Consequently, monitoring the APP concentration to ensure product integrity and facilitate the efficacious management of wastewater from production processes is of great significance. A fluorescent assay was devised to swiftly discern APP utilizing 4',6'-diamino-2-phenylindole (DAPI). With increasing APP concentrations, DAPI undergoes intercalation within its structure, emitting pronounced fluorescence. Notably, the flame retardant JLS-PNA220-A, predominantly comprising APP, was employed as the test substrate. Establishing a linear relationship between fluorescence intensity (F-F0) and JLS-PNA220-A concentration yielded the equation y = 76.08x + 463.2 (R2 = 0.9992), with a LOD determined to be 0.853 mg/L. The method was used to assess the degradation capacity of APP-degrading bacteria. Strain D-3 was isolated, and subsequent analysis of its 16S DNA sequence classified it as belonging to the Acinetobacter genus. Acinetobacter nosocomialis D-3 demonstrated superior APP degradation capabilities under pH 7 at 37 °C, with degradation rates exceeding 85% over a four-day cultivation period. It underscores the sensitivity and efficacy of the proposed method for APP detection. Furthermore, Acinetobacter nosocomialis D-3 exhibits promising potential for remediation of residual APP through environmental biodegradation processes.


Assuntos
Acinetobacter , Biodegradação Ambiental , Polifosfatos , Acinetobacter/metabolismo , Acinetobacter/genética , Polifosfatos/metabolismo , Polifosfatos/química , Indóis/metabolismo , Indóis/química , Compostos de Amônio/metabolismo , Compostos de Amônio/química , Retardadores de Chama/metabolismo , Retardadores de Chama/análise
10.
Islets ; 16(1): 2361996, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38833523

RESUMO

Epidemiological studies consistently link environmental toxicant exposure with increased Type 2 diabetes risk. Our study investigated the diabetogenic effects of a widely used flame retardant, Dechlorane Plus (DP), on pancreatic ß-cells using rodent and human model systems. We first examined pancreas tissues from male mice exposed daily to oral gavage of either vehicle (corn oil) or DP (10, 100, or 1000 µg/kg per day) and fed chow or high fat diet for 28-days in vivo. DP exposure did not affect islet size or endocrine cell composition in either diet group. Next, we assessed the effect of 48-hour exposure to vehicle (DMSO) or DP (1, 10, or 100 nM) in vitro using immortalized rat ß-cells (INS-1 832/3), primary mouse and human islets, and human stem-cell derived islet-like cells (SC-islets). In INS-1 832/3 cells, DP did not impact glucose-stimulated insulin secretion (GSIS) but significantly decreased intracellular insulin content. DP had no effect on GSIS in mouse islets or SC-islets but had variable effects on GSIS in human islets depending on the donor. DP alone did not affect insulin content in mouse islets, human islets, or SC-islets, but mouse islets co-exposed to DP and glucolipotoxic (GLT) stress conditions (28.7 mM glucose + 0.5 mM palmitate) had reduced insulin content compared to control conditions. Co-exposure of mouse islets to DP + GLT amplified the upregulation of Slc30a8 compared to GLT alone. Our study highlights the importance and challenges of using different in vitro models for studying chemical toxicity.


Assuntos
Hidrocarbonetos Clorados , Células Secretoras de Insulina , Compostos Policíclicos , Animais , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Humanos , Camundongos , Masculino , Compostos Policíclicos/farmacologia , Hidrocarbonetos Clorados/toxicidade , Ratos , Insulina/metabolismo , Retardadores de Chama/toxicidade , Secreção de Insulina/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Células Cultivadas
11.
Aquat Toxicol ; 272: 106979, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823072

RESUMO

Tris(2-chloroethyl) phosphate (TCEP) and tris(1­chloro-2-propyl) phosphate (TCPP) are widely used as chlorinated organophosphate flame retardants (OPFRs) due to their fire-resistance capabilities. However, their extensive use has led to their permeation and pollution in aquatic environments. Using amphibians, which are non-model organisms, to test the toxic effects of OPFRs is relatively uncommon. This study examined the acute and chronic toxicity differences between TCEP and TCPP on Polypedates megacephalus tadpoles and evaluated the potential ecological risks to tadpoles in different aquatic environments using the risk quotient (RQ). In acute toxicity assay, the tadpole survival rates decreased with increased exposure time and concentrations, with TCEP exhibiting higher LC50 values than TCPP, at 305.5 mg/L and 70 mg/L, respectively. In the chronic assay, prolonged exposure to 300 µg/L of both substances resulted in similar adverse effects on tadpole growth, metamorphosis, and hepatic antioxidant function. Based on RQ values, most aquatic environments did not pose an ecological risk to tadpoles. However, the analysis showed that wastewater presented higher risks than rivers and drinking water, and TCPP posed a higher potential risk than TCEP in all examined aquatic environments. These findings provide empirical evidence to comprehend the toxicological effects of OPFRs on aquatic organisms and to assess the safety of aquatic environments.


Assuntos
Anuros , Retardadores de Chama , Larva , Organofosfatos , Compostos Organofosforados , Poluentes Químicos da Água , Animais , Retardadores de Chama/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Compostos Organofosforados/toxicidade , Medição de Risco , Organofosfatos/toxicidade , Anuros/crescimento & desenvolvimento , Metamorfose Biológica/efeitos dos fármacos , Testes de Toxicidade Aguda , Dose Letal Mediana
12.
Chem Biol Interact ; 397: 111088, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823534

RESUMO

Tris(2-butoxyethyl) phosphate (TBOEP) is an organophosphorus flame retardant ubiquitously present in the environment and even the human body. TBOEP is toxic in multiple tissues, which forms dealkylated and hydroxylated metabolites under incubation with human hepatic microsomes; however, the impact of TBOEP metabolism on its toxicity, particularly mutagenicity (typically requiring metabolic activation), is left unidentified. In this study, the mutagenicity of TBOEP in human hepatoma cell lines (HepG2 and C3A) and the role of specific CYPs were studied. Through molecular docking, TBOEP bound to human CYP1A1, 1B1, 2B6 and 3A4 with energies and conformations favorable for catalyzing reactions, while the conformations of its binding with human CYP1A2 and 2E1 appeared unfavorable. In C3A cells (endogenous CYPs being substantial), TBOEP exposing for 72 h (2-cell cycle) at low micromolar levels induced micronucleus, which was abolished by 1-aminobenzotriazole (inhibitor of CYPs); in HepG2 cells (CYPs being insufficient) TBOEP did not induce micronucleus, whose effect was however potentiated by pretreating the cells with PCB126 (CYP1A1 inducer) or rifampicin (CYP3A4 inducer). TBOEP induced micronucleus in Chinese hamster V79-derived cell lines genetically engineered for stably expressing human CYP1A1 and 3A4, but not in cells expressing the other CYPs. In C3A cells, TBOEP selectively induced centromere protein B-free micronucleus (visualized by immunofluorescence) and PIG-A gene mutations, and elevated γ-H2AX rather than p-H3 (by Western blot) which indicated specific double-strand DNA breaks. Therefore, this study suggests that TBOEP may induce DNA/chromosome breaks and gene mutations in human cells, which requires metabolic activation by CYPs, primarily CYP1A1 and 3A4.


Assuntos
Sistema Enzimático do Citocromo P-450 , Retardadores de Chama , Simulação de Acoplamento Molecular , Animais , Humanos , Retardadores de Chama/toxicidade , Cricetinae , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Mutagênicos/toxicidade , Compostos Organofosforados/toxicidade , Cricetulus , Organofosfatos/toxicidade , Células Hep G2 , Testes para Micronúcleos
13.
Int J Biol Macromol ; 273(Pt 2): 132775, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823732

RESUMO

A novel flame retardant containing Si, N, and S elements, ((2-(triethoxysilyl)ethyl)thio)ethan-1-amine hydrochloride (TETEA), was synthesized via a click reaction and characterized using nuclear magnetic resonance spectroscopy (NMR) and fourier transform infrared spectroscopy (FTIR). Subsequently, the flame-retardant cotton fabric was fabricated by sol-gel method. The results indicated that TETEA was successfully loaded on cotton fabric and formed a uniform protective layer on the surface of cotton fabric, exhibiting excellent flame retardancy. The flame-retardant cotton fabric achieved limiting oxygen index (LOI) of 28.3 % and passed vertical combustion test without after-flame or afterglow time at TETEA concentration of 500 g/L. Thermogravimetric analysis revealed that the residual carbon content of the flame-retardant cotton fabric was much higher than that of the control under air and N2 conditions. Besides, the flame-retardant cotton fabric was not ignited in cone calorimeter test with an external heat flux of 35 kW/m2. The peak heat release rate and the total heat release decreased from 133.4 kW/m2 to 25.8 kW/m2 and from 26.46 MJ/m2 to 17.96 MJ/m2, respectively. This phosphorus-free flame retardant offers a simplified synthesis process without adverse environmental impacts, opening up a new avenue for the development environmentally friendly flame retardants compared to traditional alternatives.


Assuntos
Celulose , Fibra de Algodão , Retardadores de Chama , Retardadores de Chama/síntese química , Retardadores de Chama/análise , Fibra de Algodão/análise , Celulose/química , Celulose/análogos & derivados , Nitrogênio/química , Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química
14.
Int J Biol Macromol ; 273(Pt 2): 132643, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823751

RESUMO

In the field of building energy conservation, the development of biodegradable biomass aerogels with excellent mechanical performance, flame retardancy and thermal insulation properties is of particular importance. Here, a directional freeze-drying method was used for fabricating composite sodium alginate (SA) aerogels containing functionalized ammonium polyphosphate (APP) flame retardant. In particular, APP was coated with melamine (MEL) and phytic acid (PA) by a supramolecular assembly process. Through optimizing the flame retardant addition, the SA-20 AMP sample exhibited excellent flame retardant and thermal insulation properties, with the limiting oxygen index of 38.2 % and the UL-94 rating of V-0. Such aerogels with anisotropic morphology demonstrated a low thermal conductivity of 0.0288 (W/m·K) in the radial direction (perpendicular to the lamellar structure). In addition, as-obtained aerogels displayed remarkable water stability and mechanical properties, indicating significant potential for practical applications.


Assuntos
Alginatos , Retardadores de Chama , Géis , Alginatos/química , Géis/química , Triazinas/química , Condutividade Térmica , Ácido Fítico/química , Polifosfatos/química , Fósforo/química , Nitrogênio/química
15.
Int J Biol Macromol ; 273(Pt 2): 132811, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38825282

RESUMO

Atmospheric drying method for fabricating aerogels is considered the most promising way for casting aerogels on a large scale. However, the organic solvent exchange, remaining environmental pollution risk, is a crucial step in mitigating the impact of surface tension during the atmospheric drying process, especially for wet gel formed through the alkoxy-derived sol-gel process, such as melamine-formaldehyde resin (MF) aerogel. Herein, a tough polymer-assisted in situ polymerization was proposed to fabricate MF resin aerogel with a combination of mechanical toughness and strength, enabling it to withstand the capillary force during water evaporation. The monolithic MF resin aerogel through the sol-gel method can be directly prepared without additional network strengthening or organic solvent exchange. The resulting MF resin aerogel exhibits a homogeneous as well as hierarchical structure with macropores and mesopores (~6 µm and ~5 nm), high compressive modulus of 31.8 MPa, self-extinguishing property, and high-temperature thermal insulation with 97 % heat decrease for butane flame combustion. This work presents a straightforward and environmentally friendly method for fabricating MF resin aerogels with nanostructures and excellent performance in open conditions, exhibiting various applications.


Assuntos
Retardadores de Chama , Géis , Triazinas , Triazinas/química , Géis/química , Pressão , Solventes/química , Resinas Sintéticas/química , Dessecação/métodos , Porosidade , Polimerização
16.
Int J Biol Macromol ; 273(Pt 1): 132777, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38834113

RESUMO

In this work, a bio-based material (CGP) is obtained by combing chitosan, gelatin and polyvinyl alcohol through a simple solution mixing to simultaneously address polylactic acid film (PLA)' flammability and poor barrier, toughness and antibacterial properties by soaking. The results of open fire testing show that modified PLA films can effectively prolong the combustion time, improve the thermal stability and reduce the release of heat in the cone calorimeter test. For the PLA sample after soaking for 5 times (PLA-5) in particular, it can reduce the peak heat release rate (pHRR) and total heat release (THR) values to 85.8 kW/m2 and 1.3 MJ/m2 from the values of 129.5 kW/m2 and 1.8 MJ/m2 for PLA, respectively. Structural analysis suggests that CGP primarily operates in the condensed phase by forming physical barriers. Meanwhile, the modified PLA films can exhibit superior barrier effects, which indicate the oxygen transmission rate value of PLA-5 decreases to 0.9 cm3/(m2·day) from the 392.5 cm3/(m2·day) of raw PLA film. Moreover, the PLA-5 also have excellent toughness (the value increased to 200.5 % from 31.0 %) and persistent antibacterial effects (it still has 100 % sterilization after 500 days).


Assuntos
Antibacterianos , Poliésteres , Poliésteres/química , Antibacterianos/farmacologia , Antibacterianos/química , Quitosana/química , Retardadores de Chama , Fenômenos Mecânicos , Gelatina/química , Álcool de Polivinil/química , Staphylococcus aureus/efeitos dos fármacos
17.
Int J Biol Macromol ; 273(Pt 1): 132836, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38834127

RESUMO

The polyurethane (PU) foams can be functionally tailored by modifying the formulation with different additives. One such additive is melamine (MA) formaldehyde resin for improving their flame-retardant properties. In this work, the glycerol-modified (GMF), sodium alginate (SGMF)- and lignosulfonate-modified melamine formaldehyde (LGMF) were prepared and used as flame retardants reacting with isocyanate to prepare the corresponding rigid polyurethane foams (GMF-PU, SGMF-PU and LGMF-PU). The thermomechanical properties and flame-retardant properties of the foams were characterized. The results showed that the specific compression strength of GMF-PU, SGMF-PU and LGMF-PU increased substantially compared to the foams from physical addition of MA, sodium alginate and lignosulfonate, all of which were greater than that of the foam without any flame retardant (PPU). Meanwhile, the cell wall of the foam pores became thicker and the closed pore ratio increased. The sodium alginate and lignosulfonate played a key role in enhancing foam thermal stability. The limiting oxygen index values and cone calorimetry results indicated the flame-retardant efficiency of GMF-PU, SGMF-PU and LGMF-PU was significantly enhanced relative to PPU. Meanwhile, the heat and smoke release results indicated sodium alginate and lignosulfonate could reduce the amount of smoke generation to different degrees during the combustion of the foam.


Assuntos
Alginatos , Retardadores de Chama , Lignina , Poliuretanos , Triazinas , Triazinas/química , Poliuretanos/química , Retardadores de Chama/análise , Lignina/química , Lignina/análogos & derivados , Alginatos/química , Resinas Sintéticas/química , Glicerol/química , Temperatura , Formaldeído/química , Formaldeído/análise
18.
Int J Biol Macromol ; 273(Pt 1): 133042, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38866277

RESUMO

Developing biobased flame retardant adhesives using a green and simple strategy has recently gained significant attention. Therefore, in this study, we have orange peel waste (OPW) and Acacia gum (AG) phosphorylated at 140 °C to synthesize biomass-derived flame retardant adhesive. OPW is a biomass material readily available in large quantities, which. Has been utilized to produce an eco-friendly, efficient adhesive. Functionalized polysaccharides were used as a binder rather than volatile, poisonous, and unsustainable petroleum-based aldehydes. The P@OPW/AG green adhesive exhibited a higher tensile strength of 11.25 MPa when applied to cotton cloth and demonstrated versatility across various substrates such as glass, cardboard, plastic, wood, and textiles. Additionally, this bio-based robust adhesive displayed remarkable flame-retardant properties. To optimize its flame retardancy, three tests were employed: the spirit lamp flame test, the vertical flammability test (VFT), and the limiting oxygen index (LOI) test. The P@OPW/AG-coated cotton fabric achieved an impressive LOI result of 42 %, while the VFT yielded a char length of only 4 cm. Additionally, during the flame test, P@OPW/AG coated cloth endured more than 845 s of continuous flame illumination. This work offers a sustainable and fire-safe method for creating environmentally friendly high-performance composites using a recyclable bio-based flame-retardant OPW/AG glue.


Assuntos
Adesivos , Retardadores de Chama , Retardadores de Chama/análise , Adesivos/química , Resistência à Tração , Goma Arábica/química , Têxteis , Biomassa , Citrus sinensis/química , Madeira/química
19.
Int J Biol Macromol ; 273(Pt 2): 133057, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38866295

RESUMO

Poly (butylene adipate-co-terephthalate)/poly (L-lactic acid) (PBAT/PLLA) is one of the most important biodegradable polymer combinations; however, they are flammable with heavy melt dripping and incompatible. To achieve the objective of flame retardation and compatibility, a hybrid polyurethane (PU) with multiple flame retardation elements is synthesized via a new ring-opening polymerization (ROP) method and integrated into PBAT/PLLA film. The PU not only dissolves in different organic solvents at mild temperature but also improves the compatibility of PBAT/PLLA. As PU with respect to PBAT/PLLA is 20 wt%, the limiting oxygen index (LOI) and UL-94 reach 25.5 % and V-0 rating, respectively. In cone calorimeter test, the peak heat release rate (pHRR) of PU/PBAT/PLLA is ahead of PBAT/PLLA, and the total heat release (THR) decreases to 25.85 MJ/m2. The fire safety is achieved successfully. The initial pyrolysis of PU promotes the formation of a seed carbon layer; it continuously breaks down into a series of phosphorus­oxygen radicals and generates different inert gases, while the pyrolytic solid products accelerate the carbonization to form the carbon/silicon composite layer. Then the polymeric combustion is braked completely. Besides, the PU can also tune the mechanical properties of PBAT/PLLA film and enhance its hydrophobicity. This work opens a new window for developing multifunctional flame retardant and paves the way for the richening engineering application of PBAT/PLLA.


Assuntos
Retardadores de Chama , Poliésteres , Poliuretanos , Poliuretanos/química , Poliésteres/química , Ácidos Ftálicos/química , Polimerização
20.
Int J Biol Macromol ; 273(Pt 2): 133158, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878937

RESUMO

Enhancing the flame retardancy and durability of cellulose fibers, particularly environmentally friendly regenerated cellulose fibers types like Lyocell fibers, is essential for advancing their broader application. This study introduced a novel approach to address this challenge. Cationic-modified Lyocell fibers (Lyocell@CAT) were prepared by introducing quaternary ammonium structures into the molecular chain of Lyocell fibers. Simultaneously, a flame retardant, APA, containing -COO-NH4+ and -P=O(O-NH4+)2 groups was synthesized. APA was then covalently bonded to Lyocell@CAT to prepare Lyocell@CAT@APA. Even after undergoing 30 laundering cycles (LCs), Lyocell@CAT@APA maintained a LOI value of 37.2 %, exhibiting outstanding flame retardant durability. The quaternary ammonium structure within Lyocell@CAT@APA formed asymmetric ionic bonds with the phosphate and carboxylate groups in APA, effectively shielding the binding of Na+ ions with phosphate groups during laundering, thereby enhancing the durability. Additionally, the consumption of Na+ ions by carboxylate groups further prevented their binding to phosphate groups, which contributed to enhance the durability properties. Flame retardant mechanism analysis revealed that both gas and condensed phase synergistically endowed excellent flame retardancy to Lyocell fibers. Overall, this innovative strategy presented a promising prospect for developing bio-safe, durable, and flame retardant cellulose textiles.


Assuntos
Celulose , Retardadores de Chama , Celulose/química , Metais/química , Ácidos Carboxílicos/química , Íons/química , Compostos de Amônio Quaternário/química
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