RESUMO
The effect of plasticizers, namely glycerol, sorbitol, and citric acid, on the structural and mechanical properties of biodegradable films obtained from xanthan gum (XG) and starch was studied. The plasticizing effect of glycerol, sorbitol, and citric acid on XG-starch films is justified by the destruction of intermolecular contacts between starch and XG macromolecules and the redistribution of hydrogen bonds in the system as a result of the hydrotropic action of plasticizer molecules. The use of glycerol proved to be the most effective for regulating the deformation of films, while the use of sorbitol to preserve strength. The dependence of the film roughness on the type and concentration of plasticizers was characterized. The smallest values of protrusions on the surface of XG-starch films were found in the presence of sorbitol. Considering the effect of the concentration of plasticizers on the stickiness of the surface of XG-starch films and their structural and mechanical properties, 1.5 % concentration of glycerol, sorbitol and citric acid was determined as optimal.
RESUMO
Accumulating epidemiological evidence underscores the association between pervasive environmental factors and an increased risk of metabolic diseases. Environmental chemicals, recognized disruptors of endocrine and metabolic processes, may contribute to the global prevalence of metabolic disorders, including obesity. Acetyl tributyl citrate (ATHC), categorized as a citric acid ester plasticizer, serves as a substitute for di-(2-ethylhexyl) phthalate (DEHP) in various everyday products. Despite its widespread use and the increasing risk of exposure in humans and animals due to its high leakage rates, information regarding the safety of exposure to environmentally relevant doses of ATHC remains limited. This study aimed to investigate the potential impact of ATHC exposure on metabolic homeostasis. Both in vivo and in vitro exposure models were used to characterize the effects induced by ATHC exposure. C57BL/6 J male mice were subjected to a diet containing ATHC for 12 weeks, and metabolism-related parameters were monitored and analyzed throughout and after the exposure period. Results indicated that sub-chronic dietary exposure to ATHC induced an increase in body fat percentage, elevated serum lipid levels, and increased lipid content in the liver tissue of mice. Furthermore, the effect of ATHC exposure on murine hepatocytes were examined and results indicated that ATHC significantly augmented lipid levels in AML12 hepatocytes, disrupting energy homeostasis and altering the expression of genes associated with fatty acid synthesis, uptake, oxidation, and secretion pathways. Conclusively, both in vivo and in vitro results suggest that exposure to low levels of ATHC may be linked to an elevated risk of obesity and fatty liver in mice. The potential implications of ATHC on human health warrant comprehensive evaluation in future studies.
RESUMO
Waste from non-degradable packaging materials poses a serious environmental risk and has led to interest in developing sustainable bio-based packaging materials. Sustainable packaging materials have been made from diverse naturally derived materials such as bamboo, sugarcane, and corn starch. In this study, we made a sustainable packaging film using chitosan extracted from the biomass of yellow mealworm (Tenebrio molitor) shell waste. The extracted chitosan was used to create films, cross-linked with citric acid (CA) and with the addition of glycerol to impart flexibility, using the solvent casting method. The successful cross-linking was evaluated using Fourier-Transform Infrared (FTIR) analysis. The CA cross-linked mealworm chitosan (CAMC) films exhibited improved water resistance with moisture content reduced from 19.9 to 14.5%. Improved barrier properties were also noted, with a 28.7% and 10.2% decrease in vapor permeability and vapor transmission rate, respectively. Bananas were selected for food preservation, and significant changes were observed over a duration of 10 days. Compared to the control sample, bananas packaged in CAMC pouches exhibited a lesser loss in weight because of excellent barrier properties against water vapor. Moreover, the quality and texture of bananas packaged in CAMC pouch remained intact over the duration of the experiment. This indicates that adding citric acid and glycerol to the chitosan structure holds promise for effective food wrapping and contributes to the enhancement of banana shelf life. Through this study, we concluded that chitosan film derived from mealworm biomass has potential as a valuable resource for sustainable packaging solutions, promoting the adoption of environmentally friendly practices in the food industry.
RESUMO
Introduction: Di(2-ethylhexyl) phthalate (DEHP) is a plasticizer commonly used in blood bags. Despite its protective effects on red blood cell (RBC) storage, concerns about its reproductive toxicity exist. This study investigated the in vitro quality of RBC concentrates stored in bags using di(isononyl) cyclohexane-1,2-dicarboxylate (DINCH) as an alternative plasticizer. Methods: Using a pool-and-split study design, we produced 20 matched homogenous quintets of RBC concentrates in two DINCH bags and three DEHP bags with citrate phosphate dextrose adenine (CPDA-1) anticoagulant. RBC storage quality was assessed weekly for 35 days. Results: On day 35, the median hemolysis levels in the DINCH bags (0.297-0.342%) were marginally higher (p < 0.05) than the DEHP bags (0.204-0.240%). All DINCH bags showed <0.8% hemolysis. RBCs in the DINCH bags showed increased mean corpuscular volume and decreased eosin 5' maleimide binding than in the DEHP bags. Higher pO2 and lower pCO2 levels in the DINCH bags indicated better gas permeability than in DEHP bags. Other metabolic parameters were comparable in both bags. Compared to DEHP, DINCH exhibited considerably lower levels of plasticizer leaching into blood bags. Conclusion: The quality of RBC concentrates stored for 35 days in DINCH-plasticized blood bags with CDPA-1 is generally comparable to those in DEHP bags. Hence, DINCH can be a viable alternative to DEHP in blood bags for nonleukoreduced RBC storage even without the use of next-generation additive solutions to improve RBC preservation quality.
A plasticizer is a chemical substance added to plastic to increase its flexibility. DEHP is a plasticizer that has been widely used in many products including plastic tubing and bags of medical devices. However, concerns about DEHP-related toxicity have been debated for many years. DEHP has been replaced with other plasticizers in many products, but it is still being used in blood bags due to its protective effect on RBC preservation. DINCH is an alternative plasticizer with a low toxicology profile. This study investigated the quality of RBC concentrates stored in blood bags using DINCH. Twenty sets of five RBC concentrates were produced using two DINCH bags and three DEHP bags with CPDA-1 anticoagulant, and the storage quality was assessed weekly for 35 days. On day 35, the median hemolysis levels in the DINCH bags (0.2970.342%) were slightly increased than the DEHP bags (0.2040.240%). However, all DINCH bags showed hemolysis lower than the regulatory limit of 0.8%. DINCH bags exhibited better gas permeability than DEHP bags. Compared to DEHP, DINCH exhibited considerably lower levels of plasticizer leaching into blood bags. Most of the other metabolic parameters were comparable in both bags. The quality of nonleukocyte-reduced RBC concentrates stored for 35 days in DINCH-plasticized blood bags with CDPA-1 is generally comparable to those in DEHP bags. Hence, DINCH can be a viable alternative to DEHP in blood bags for RBC storage, even without the use of next-generation additive solutions to improve RBC preservation quality.
RESUMO
Alternative plasticizers such as diisononyl-1,2-cyclohexanedicarboxylate (DINCH), di(2-ethylhexyl) terephthalate (DEHTP), and di(2-ethylhexyl) adipate (DEHA) are progressively replacing phthalates in many consumer and professional products because of adverse effects on reproduction associated with some phthalates. Human exposures to these phthalate substitutes can occur through ingestion, skin absorption and inhalation. Skin uptake can lead to greater concentration at the target organs compared to ingestion because the skin exposure route bypasses the first-pass effect. Skin absorption studies are almost absent for these alternative plasticizers. We therefore wanted first, to characterize skin absorption of a mixture containing DINCH, DEHA and DEHTP in vitro using a flow-through diffusion cell system with ex vivo human skin, quantifying their respective monoester metabolites (mono-isononyl-cyclohexane-1,2-dicarboxylate (MINCH), mono-2-ethylhexyl adipate (MEHA), mono-2-ethylhexyl terephthalate (MEHTP), respectively); second, to validate these results by exposing five human volunteers to this mixture on their forearm and quantifying the corresponding urinary metabolites (including the monoesters and their oxidation products). Our study showed that two of these alternative plasticizers, DEHTP and DINCH, did not permeate skin showing as quantifiable metabolite levels in vitro and only traces of DEHA were quantified as its monoester metabolite, MEHA. Permeation coefficient (Kp) 0.06 and 55.8*10-7cm/h for neat and emulsified DEHA, respectively, while the permeation rate (J) remained low for both (0.005 and 0.001µg/cm2/h, respectively). Participants exposed to a mixture of these three plasticizers did not have noteworthy urinary concentrations of their respective metabolites after 24hours post-application. However, the alternative plasticizer mixture was completely absorbed after six hours post-application on the forearms of the human volunteers, and the urinary elimination curves showed a slight increase after 24hours post-application. Further studies on skin absorption of these substances should follow the urinary elimination kinetics of these metabolites more than 24hours post-application. We also recommend quantifying the parent compounds in the in vitro diffusion experiments.
RESUMO
Background: Phthalates are additives used as plasticizers among other uses, classified as endocrine disruptors and may contribute to some metabolic disorders. The aim of this work was to determine the effect of the exposure of diethyl phthalate (DEP) and dibutyl phthalate (DBP) on cell viability and reactive oxygen species (ROS) production, as well as the regulation of sirloins in HepG2 cells. Methods: HepG2 cells were exposed to DEP or DBP at 0.1, 1, 10 and 100 µg/mL, and after 48 or 72 h the gene and protein expression of sirtuins was quantified by qRT-PCR and Western-Blot, respectively. Results: Results showed that even at a low concentration of 0.1 µg/mL DEP affected the expression of Sirt3 and Sirt4, whereas DBP at 0.1 µg/mL affected Sirt3 and Sirt5 gene expression. Protein analysis showed a reduction in Sirt1 levels at a DEP concentration of 1 µg/mL and higher, while DBP at higher dose (100 µg/mL) decreased Sirt3 protein levels. Cell viability decreased by 20% only at higher dose (100 µg/mL) and ROS production increased at 10 and 100 µg/mL for both phthalates. Conclusion: These findings indicate that exposure to low concentrations (0.1 µg/mL) of DEP or DBP can negatively influence the expression of some sirtuins.
RESUMO
Compaction pressure can induce an undesirable solid-state polymorphic transition in drugs, fragmentation, loss of coated pellet integrity, and the decreased viability and vitality of microorganisms. Thus, the excipients with increased plasticity can be considered as an option to decrease the undesirable effects of compaction pressure. This study aims to increase the plasticity (to reduce the mean yield pressure; Py) of dried microcrystalline cellulose (MCC) by loading it with a specially selected plasticizer. Diethyl citrate (DEC), water, and glycerol were the considered plasticizers. Computation of solubility parameters was used to predict the miscibility of MCC with plasticizers (possible plasticization effect). Plasticizer-loaded MCC spheres with 5.0 wt.% of water, 5.2 wt.% of DEC, and 4.2 wt.% glycerol were obtained via the solvent method, followed by solvent evaporation. Plasticizer-loaded formulations were characterised by TGA, DSC, pXRD, FTIR, pressure-displacement profiles, and in-die Heckel plots. Py was derived from the in-die Heckel analysis and was used as a plasticity parameter. In comparison with non-plasticized MCC (Py = 136.5 MPa), the plasticity of plasticizer-loaded formulations increased (and Py decreased) from DEC (124.7 MPa) to water (106.6 MPa) and glycerol (99.9 MPa), and that was in full accordance with the predicted miscibility likeliness order based on solubility parameters. Therefore, water and glycerol were able to decrease the Py of non-plasticized MCC spheres by 16.3 and 30.0%, respectively. This feasibility study showed the possibility of modifying the plasticity of MCC by loading it with a specially selected plasticizer.
RESUMO
Polylactic acid (PLA), a biodegradable polymer with low flexibility, is commonly plasticized with small molecules like tributyl citrate (TBC) for film production. However, these plasticizers, which lack chemical bonds or strong intermolecular interactions with the matrix, tend to migrate to the film surface over time. Their inclusion often compromises material strength for flexibility, increasing elongation at break but reducing tensile strength. In this research, by combining citric acid with n-butanol (B) and poly(ethylene glycol) diglycidyl ether (E), we synthesized three plasticizers, namely TE3, TE2B1, and TE1B2, to enhance the flexibility of PLA. TE2B1 and TE1B2 are equipped with butyl ester groups that offer effective plasticizing effects. Additionally, the incorporation of long-chain alkyl featuring epoxy groups can boost the interaction with PLA. The results showed that the epoxy groups of the long-chain alkyl plasticizers can improve the elongation at break without compromising tensile strength significantly. The migration of plasticizer from PLA matrix can be reduced by strong interactions like chemical bonds, entanglements, and hydrogen bonding with PLA. TE1B2 demonstrated the best plasticizing effect. Adding 15 portions of TE1B2 and TBC separately increased PLA's elongation at break to 304 % and 242 %, with tensile strengths of 36.1 MPa and 22.3 MPa, respectively.
RESUMO
CONTEXT: Thermoplastic elastomer styrene-ethylene-butylene-styrene block copolymer (SEBS) has excellent mechanical properties and aging resistance, so it has good application prospects in thermoplastic solid propellants. The selection of plasticizer is one of the keys to the formulation design of thermoplastic solid propellant. The compatibility of the plasticizer with the polymer determines the plasticizer's ability to plasticize the polymer's molecular chain segments. Herein, the compatibility of four plasticizers with SEBS was investigated, and the results declared that the order of compatibility between SEBS and the four plasticizers is SEBS/WO > SEBS/DOS > SEBS/DEP > SEBS/TA. METHODS: Physical compatibility of SEBS binder with plasticizer triacetin (TA), diethyl phthalate (DEP), dioctyl sebacate (DOS), and 26# industrial white oil (WO) was simulated using molecular dynamics (MD) method via Materials Studio 8.0, and the simulation results were verified experimentally. The results showed that the compatibility of SEBS with these plasticizers can be comprehensively evaluated by analyzing solubility parameters, radial distribution functions, and blend miscibility simulations.
RESUMO
Owing to growing concerns about the adverse effects of phthalate plasticizers, non-phthalate plasticizers are being increasingly used as their replacement. However, information on the residual environmental concentrations and ecological risks posed by these plasticizers is limited. In this study, we analyzed the environmental contamination of 11 phthalates and 5 non-phthalate plasticizers in Class A and B rivers in Japan. In the considered river water samples, phthalates and non-phthalates were detected in the following order of detection frequency: phthalates (DEHP > DMP > DMEP > BBP > DNPP > DNP > DEEP > DBEP = DNOP) and non-phthalates (ATBC > DEHS > DEHA > TOTM = DIBA). Phthalate plasticizers were the most abundant and included DEHP (157-859 ng/L), DMP (Assuntos
Monitoramento Ambiental
, Estuários
, Ácidos Ftálicos
, Plastificantes
, Rios
, Poluentes Químicos da Água
, Plastificantes/análise
, Japão
, Rios/química
, Medição de Risco
, Poluentes Químicos da Água/análise
, Ácidos Ftálicos/análise
RESUMO
The use of vegetable oil-dervied plasticizers to enhance the flexibility of polylactic acid (PLA) has received much attention due to their renewability, inexpensiveness and biodegradation. However, the double bonds in vegetable oil-based plasticizers limit their compatibility with PLA, resulting in PLA-derived products with reduced flexibility. Herein, we examined soybean oil-derived hydrogenated dimer acid-based polyethylene glycol methyl ether esters (HDA-2n, 2n = 2, 4, 6 or 8, referring to the ethoxy units) developed via the direct esterification of saturated hydrogenated dimer acid and polyethylene glycol monomethyl ethers. The resulting HDA-2n was first used as a plasticizer for PLA, and the effects of the ethoxy units in HDA-2n on the overall performance of the plasticized PLA were systematically investigated. The results showed that, compared with PLA blended with dioctyl terephthalate (DOTP), the PLA plasticized by HDA-8 with the maximum number of ethoxy units (PLA/HDA-8) exhibited better low-temperature resistance (40.1 °C vs. 15.3 °C), thermal stability (246.8 °C vs. 327.6 °C) and gas barrier properties. Additionally, the biodegradation results showed that HDA-8 could be biodegraded by directly burying it in soil. All results suggest that HDA-8 could be used as green alternative to the traditional petroleum-based plasticizer DOTP, which is applied in the PLA industry.
RESUMO
This study investigated a blend of poly (lactic acid) (PLA) and Saqqez gum, with a weight ratio of 70:30, respectively, along with two plasticizers, acetyl tributyl citrate (ATBC) and polyethylene glycol (PEG), at three different concentrations (14%, 16% and 18% by weight of the PLA). The blend was analyzed using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), tensile tests, water-absorption behavior (coefficients of water absorption, sorption, diffusion and permeability of the samples during 240 h) and chemical resistance (exposure to 1 mol/L HCl and 1 mol/L NaOH for 240 h). The desired elastomer blend was then used to prepare natural chewing gum, which was subsequently subjected to texture profile analyzer (TPA) tests and sensory evaluation. The results showed that the addition of both plasticizers increased the tensile properties of the blend. Compared to neat PLA, all the blends exhibited an increase in elongation at break and a decrease in yield strength, with the maximum elongation at break (130.6%) and the minimum yield strength (12.2 MPa) observed in the blend containing 16% ATBC. Additionally, all the thermal attributes studied, including Tg, Tc and Tm, were lower than those of neat PLA, and the Tg values deviated from the values predicted via Fox's equation. SEM images of the blends confirmed that plasticization improved the homogeneity and distribution of the components in the blend structure. PEG 18% and ATBC 16% exhibit the highest and lowest water-absorption behavior, respectively. Regarding chemical resistance, all blends showed weight gain when exposed to HCl, while no weight loss was observed for resistance to NaOH. The chewing gum sample obtained similar values for the mentioned tests compared to the commercial control sample. Overall, the results indicate that plasticization enhances the structure and performance of the PLA/Saqqez gum blend and further investigation is warranted.
RESUMO
This study investigates the performance of biopolymer electrolytes based on chitosan and dextran for energy storage applications. The optimization of ion transport and performance of electric double-layer capacitors EDCL using these electrolytes, incorporating different concentrations of glycerol as a plasticizer and TiO2 as nanoparticles, is explored. Impedance measurements indicate a notable reduction in charge transfer resistance with the addition of TiO2. DC conductivity estimates from AC spectra plateau regions reach up to 5.6 × 10-4 S/cm. The electric bulk resistance Rb obtained from the Nyquist plots exhibits a substantial decrease with increasing plasticizer concentration, further enhanced by the addition of the nanoparticles. Specifically, Rb decreases from â¼20 kΩ to 287 Ω when glycerol concentration increases from 10 % to 40 % and further drops to 30 Ω with the introduction of TiO2. Specific capacitance obtained from cyclic voltammetry shows a notable increase as the scan rate decreases, indicating improved efficiency and stability of ion transport. The TiO2-enriched EDCL achieves 12.3 F/g specific capacitance at 20 mV/s scan rate, with high ion conductivity and extended electrochemical stability. These results suggest the great potential of plasticizer and TiO2 with biopolymers in improving the performance of energy storage systems.
Assuntos
Quitosana , Dextranos , Eletrólitos , Transporte de Íons , Titânio , Titânio/química , Quitosana/química , Eletrólitos/química , Dextranos/química , Capacitância Elétrica , Condutividade Elétrica , Plastificantes/químicaRESUMO
Background: Exposure to a mixture of environmental chemicals may cause gallstone, but the evidence remains equivocal. The current study aims to investigate the association between phthalate metabolites and gallstones, and to explore their mediators. Methods: Data from the National Health and Nutrition Examination Survey 2017-2018 on U.S. adults (≥20 years) were analyzed to explore the association between phthalate metabolites and gallstones by employed survey-weighted logistic regression, restricted cubic spline (RCS), weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR). Mediation analyses examined the role of oxidative stress markers, inflammatory markers, metabolic syndrome, body composition, diabetes, and insulin. Results: The current study included 1,384 participants, representing 200.6 million U.S. adults. Our results indicated a significant association between phthalate metabolites, particularly high molecular weight metabolites such as Di(2-ethylhexyl) phthalate (DEHP) and 1,2-Cyclohexane dicarboxylic acid diisononyl ester (DINCH), and gallstones. Furthermore, mediation analyses indicated that phthalate metabolites may play a role in the development of gallstones by influencing insulin secretion. Subgroup analyses did not reveal significant interaction. Conclusion: The association between exposure to phthalates and the occurrence of gallstones, potentially mediated by hyperinsulinemia from a nationally representative epidemiological perspective. These insights contribute to a better understanding of the potential health implications of plasticizers, emphasizing the need for proactive management measures.
Assuntos
Cálculos Biliares , Insulina , Inquéritos Nutricionais , Ácidos Ftálicos , Humanos , Feminino , Masculino , Adulto , Insulina/metabolismo , Pessoa de Meia-Idade , Cálculos Biliares/induzido quimicamente , Estados Unidos/epidemiologia , Exposição Ambiental/efeitos adversos , Teorema de BayesRESUMO
Plasticizers are necessary for the usability of various products, including food contact materials. Exposure to plasticizers is most commonly made through the oral route. Several plasticizers have been reported to have adverse effects on humans and the environment. Thus, the present study aimed to determine the long-term toxicity and carcinogenicity of a novel plasticizer called bis(2-ethylhexyl) cyclohexane-1,4-dicarboxylate (Eco-DEHCH), which is an ecofriendly and biologically less harmful replacer. Groups of 50 male and 50 female Han Wistar rats were fed Eco-DEHCH at daily doses of 1,600, 5,000, or 16,000 ppm in their diet for at least 104 weeks. The rats were regularly monitored for mortality, clinical signs, body weight, food consumption, food efficiency, and perceivable mass. All animals were subjected to complete necropsy and histopathological examination. The results indicate that the rats well tolerated chronic exposure to Eco-DEHCH at highest daily doses of 16,000 ppm, with was equivalent to 805.1 mg/kg/day in males and 1060.6 mg/kg/day in females and did not show signs of toxicity or carcinogenicity. In conclusion, Eco-DEHCH could be a safe and promising alternative plasticizer.
Assuntos
Testes de Carcinogenicidade , Plastificantes , Ratos Wistar , Animais , Plastificantes/toxicidade , Masculino , Feminino , Ratos , Administração Oral , Ácidos Dicarboxílicos/toxicidade , Ácidos Dicarboxílicos/administração & dosagem , Relação Dose-Resposta a Droga , Cicloexanos/toxicidade , Cicloexanos/administração & dosagem , DietaRESUMO
The plant pigments called betalains are nutritionally safe polar compounds. They are subdivided into betaxanthins (having orange to yellow hues) and betacyanins (purple to red violet hues). Betacyanins change color with a change in pH, particularly in the range 6-8 and 9-11. Perishable foods like fish, chicken, beef, pork, and others tend to release total volatile base-nitrogen (TVB-N) during storage or deterioration, which leads to a change in the pH of pH-sensitive materials in the vicinity. pH-sensitive pigment-incorporated polymeric films with inherent active properties (or active/intelligent films) are increasingly being studied as an alternative to synthetic pH indicators to detect the accumulation of TVB-N by changing its color to indicate the stage of perishable food spoilage. There are many methods of developing such films under different conditions using different bio-based biodegradable polymer(s) and biocompatible plasticizer combinations. Among the reported methods, solution casting method has been the preferred one in most studies covered in this review. This method can be carried out under mild conditions. As such, betacyanins-incorporated polymeric films essentially require mild processing conditions because of their heat sensitivity, which will invariably affect the performance in food freshness monitoring. In this review, film fabrication parameters like temperature and duration of dissolution of polymers, plasticizer concentration, pH of the film-forming solution, film drying, and conditioning/aging, have been critically appraised based on the available literature. The lack of studies on the safety of active/intelligent films has been systematically highlighted in this review to focus future studies on this area.
RESUMO
In the United States and abroad, ortho-phthalates and non-ortho-phthalate plasticizers continue to be used within a diverse array of consumer products. Prior California-specific biomonitoring programs for ortho-phthalates have focused on rural, agricultural communities and, to our knowledge, these programs have not measured the potential for exposure to non-ortho-phthalate plasticizers. Therefore, the potential for human exposure to ortho-phthalates and non-ortho-phthalate plasticizers have not been adequately addressed in regions of California that have higher population density. Since there are numerous sources of ortho-phthalates and non-ortho-phthalate plasticizers in population-dense, urban regions, the objective of this study was to leverage silicone wristbands to quantify aggregate ortho-phthalate and non-ortho-phthalate plasticizer exposure over a 5-day period across two different cohorts (2019 and 2020) of undergraduate students at the University of California, Riverside (UCR) that commute from all over Southern California. Based on 5 d of aggregate exposure across two different cohorts, total ortho-phthalate plus non-ortho-phthalate plasticizer concentrations ranged, on average, from â¼100,000-1,000,000 ng/g. Based on the distribution of individual ortho-phthalate and non-ortho-phthalate plasticizer concentrations, the concentrations of di-isononyl phthalate (DiNP, a high molecular weight ortho-phthalate), di (2-ethylhexyl) phthalate (DEHP, a high molecular weight ortho-phthalate), and di-2-ethylhexyl terephthalate (DEHT, a non-ortho-phthalate plasticizer) detected within wristbands were higher than the remaining seven ortho-phthalates and non-ortho-phthalate plasticizers measured, accounting for approximately 94-97% of the total mass depending on the cohort. Overall, our findings raise concerns about chronic DiNP, DEHP, and DEHT exposure in urban, population-dense regions throughout California.
Assuntos
Exposição Ambiental , Ácidos Ftálicos , Plastificantes , Humanos , Plastificantes/análise , California , Ácidos Ftálicos/análise , Exposição Ambiental/análise , Silicones/química , Poluentes Ambientais/análise , Feminino , Masculino , Adulto Jovem , Monitoramento Ambiental/métodos , Punho , AdultoRESUMO
Nowadays, substituting petroleum-based plastics with biodegradable polymers made from polysaccharides loaded with various reinforcing materials has recently gained attention due to the impact of conventional plastics wastes. In this study, polysaccharidic mucilage from Ethiopian cactus (Opuntia Ficus Indica) was derived using microwave-assisted extraction technique to develop biodegradable polymers that were inexpensive, readily available, simple to make, and ecofriendly. The effect of microwave power 300-800 W, solid-liquid (cactus-sodium hydroxide solution) ratio 1:5-1:25, sodium hydroxide concentration 0.1-0.8 mol/L, and extraction time 2-10 min on mucilage extraction were studied and the maximum yield of mucilage was attained at optimized parameters of 506 W, 1:20, 0.606 mol/L, and 9.5 min, respectively. Biodegradable polymers made with mucilage alone have poor mechanical characteristics and are thermally unstable. Thus, to overcome the stated problems, glycerol as a plasticizer and acid-leached kaolin crosslinked with urea as a reinforcing material were used. Moreover, the effect of acid-leached kaolin and glycerol on the physico-chemical properties of the films was studied, and a maximum tensile strength of 6.74 MPa with 18.45 % elongation at break, thermally improved biodegradability of 26 %, were attained at 10 % acid-leached kaolin and 20 % glycerol crosslinking with 2 % urea. But the maximum degradability of 53.5 % was attained at 30 % glycerol content. The control and reinforced biodegradable films were characterized using TGA, FTIR, SEM, and XRD to determine the thermal, functional group, morphology, and crystallinity of the bioplastics, respectively. These biodegradable plastics may be used for packaging application.
RESUMO
A comprehensive study was undertaken to examine the contamination of spotted scat fish (Scatophagus argus) with microplastics (MP) in various locations along the East Java coast of Indonesia. The purpose of this study was to collect detailed information regarding the abundance, color, shape, size, type of polymer, and chemical components of the MP. The findings of this study indicated that MP exhibiting distinct attributes-including a specific fiber type, black coloration, and a size range of 1000- <5000 µm-was most abundant in the gill, stomach, and intestines of spotted scat fish of varying lengths. And MP with a size range of 100-<500 µm was prevalent in the sediment. MP with black fragments measuring less than 100 µm in diameter were found primarily in seawater. A positive correlation was identified between fish length and MP abundance in the intestines, as indicated by the Spearman correlation coefficient. Conversely, a negative correlation was detected between fish length and MP abundance in the gills. The findings of the Fourier transform infrared spectroscopy and Gas chromatography-mass spectrometry analyses, which indicate the presence of various polymers and chemical substances including plasticizers (e.g., diethyl phthalate, decane, and eicosane), stabilizers (2-piperidinone, hexadecanoic acid, mesitylene, and 2,4-Di-tert-butylphenol), and flame retardant (cyclododecene), in fish, are of the utmost importance. These substances have the potential to endanger the health of both animals and humans if they are ingested through the food chain.
Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Microplásticos , Água do Mar , Poluentes Químicos da Água , Animais , Indonésia , Água do Mar/química , Poluentes Químicos da Água/análise , Microplásticos/análise , Sedimentos Geológicos/química , Peixes/metabolismo , Brânquias/química , Cromatografia Gasosa-Espectrometria de Massas , PerciformesRESUMO
As an alternative plasticizer to conventional phthalates, di(2-ethylhexyl) terephthalate (DEHTP) has attracted considerable concerns, given its widespread detection in the environment and humans. However, the potential toxicity, especially liver toxicity, posed by DEHTP remains unclear. In this study, based on the 2017-2018 National Health and Nutrition Examination Survey, two metabolites of DEHTP, i.e., mono(2-ethyl-5-hydroxyhexyl) terephthalate (MEHHTP) and mono(2-ethyl-5-carboxypentyl) terephthalate (MECPTP), were found to be present in the urine samples of nearly all representative U.S. adults. Moreover, a positive linear correlation was observed between the concentrations of the two metabolites and the risk of nonalcoholic fatty liver disease (NAFLD) in the population. Results of weighted quantile sum and Bayesian kernel machine regression indicated that MEHHTP contributed a greater weight to the risk of NAFLD in comparison with 12 conventional phthalate metabolites. In vitro experiments with hepatocyte HepG2 revealed that MEHHTP exposure could increase lipogenic gene programs, thereby promoting a dose-dependent hepatic lipid accumulation. Activation of liver X receptor α may be an important regulator of MEHHTP-induced hepatic lipid disorders. These findings provide new insights into the liver lipid metabolism toxicity potential of DEHTP exposure in the population.