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1.
Molecules ; 28(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615648

RESUMO

In order to broaden the study of energetic cations, a cation 3,5-diamino-4H-pyrazol-4-one oxime (DAPO) with good thermal stability was proposed, and its three salts were synthesized by a simple and efficient method. The structures of the three salts were verified by infrared spectroscopy, mass spectrometry, elemental analysis, and single crystal X-ray diffraction. The thermal stabilities of the three salts were verified by differential scanning calorimetry and thermos-gravimetric analysis. DAPO-based energetic salts are analysed using a variety of theoretical techniques, such as 2D fingerprint, Hirshfeld surface, and non-covalent interaction. Among them, the energy properties of perchlorate (DAPOP) and picrate (DAPOT) were determined by EXPLO5 program combined with the measured density and enthalpy of formation. These compounds have high density, acceptable detonation performance, good thermal stability, and satisfactory sensitivity. The intermolecular interactions of the four compounds were studied by Hirshfeld surface and non-covalent interactions, indicating that hydrogen bonds and π-π stacking interactions are the reasons for the extracellular properties of perchlorate (DAPOP) and picrate (DAPOT), indicating that DAPO is an optional nitrogen-rich cation for the design and synthesis of novel energetic materials with excellent properties.


Assuntos
Percloratos , Sais , Picratos , Oximas
2.
Environ Pollut ; 318: 120856, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36513174

RESUMO

Perchlorate is a stable and readily transportable thyroid hormone disruptor, and prevalent exposure to perchlorate through food and drinking water has raised public concern about its health effects. The physiologically based toxicokinetic (PBTK) model as a dose prediction method is effective to predict the toxicant exposure dose of an organism and helps quantitatively assess the dose-dependent relationship with toxic effects. The current study aimed to establish a multi-compartment PBTK model based on updated time-course datasets of single oral exposure to perchlorate in rats. With adjustment of the kinetic parameters, the model fitted well the toxicokinetic characteristics of perchlorate in urine, blood, and thyroid from our experiments and the literature, and the coefficient of determination (R2) between the fitting values and the experimental data in regression analysis was greater than 0.91, indicating the robustness of the current model. The results of sensitivity analysis and daily repeated exposure simulations together confirmed its effective renal clearance. According to the distribution characteristic of perchlorate, a correlation study of internal and external exposure was conducted using urinary perchlorate as a bioassay indicator. The developed multi-compartment model for perchlorate updates important toxicokinetic data and kinetic parameters, providing analytical and modeling tools for deriving total exposure levels in the short term.


Assuntos
Água Potável , Percloratos , Ratos , Animais , Percloratos/toxicidade , Toxicocinética , Cinética , Modelos Biológicos
3.
Environ Int ; 171: 107713, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36565572

RESUMO

BACKGROUND: Evidence on environmental exposure to perchlorate, nitrate, and thiocyanate, three thyroidal sodium iodine symporter (NIS) inhibitors, and thyroid function in the Chinese population remains limited. OBJECTIVE: To investigate the associations of environmental exposure to perchlorate, nitrate, and thiocyanate with markers of thyroid function in Chinese adults. METHODS: A total of 2441 non-pregnant adults (mean age 50.4 years and 39.1% male) with a median urinary iodine of 180.1 µg/L from four communities in Shenzhen were included in this cross-sectional study. Urinary perchlorate, nitrate, thiocyanate, and thyroid profiles, including serum free thyroxine (FT4), total thyroxine (TT4), free triiodothyronine (FT3), total triiodothyronine (TT3), and thyroid stimulating hormone (TSH), were measured. Generalized linear model was applied to investigate the single-analyte associations. Weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) models were used to examine the association between the co-occurrence of three anions and thyroid profile. RESULTS: The median levels of urinary perchlorate, nitrate, and thiocyanate were 5.8 µg/g, 76.4 mg/g, and 274.1 µg/g, respectively. After adjusting for confounders, higher urinary perchlorate was associated with lower serum FT4, TT4, and TT3, and higher serum FT3 and TSH (all P < 0.05). Comparing extreme tertiles, subjects in the highest nitrate tertile had marginally elevated TT3 (ß: 0.02, 95% CI: 0.00-0.04). Each 1-unit increase in log-transformed urinary thiocyanate was associated with a 0.04 (95% CI: 0.02-0.06) pmol/L decrease in serum FT3. The WQS indices were inversely associated with serum FT4, TT4, and FT3 (all P < 0.05). In the BKMR model, the mixture of three anions was inversely associated with serum FT4, TT4, and FT3. CONCLUSIONS: Our study provides evidence that individual and combined environmental exposure to perchlorate, nitrate, and thiocyanate are associated with significant changes in thyroid function markers in the Chinese population with adequate iodine intake.


Assuntos
Iodo , Glândula Tireoide , Adulto , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Tiroxina , Nitratos , Estudos Transversais , Tri-Iodotironina , Tiocianatos/urina , Percloratos/efeitos adversos , Percloratos/urina , Teorema de Bayes , Exposição Ambiental/efeitos adversos , Tireotropina , Iodo/urina
4.
Water Res ; 230: 119531, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36580803

RESUMO

Electrochemical advanced oxidation process (EAOP) is recommended for high-strength refractory organics wastewater treatment, but the accompanying chlorinated byproduct generation becomes a bottleneck that limits the application of this technology to actual wastewater. In this study, we applied EAOP (0.4-40 mA cm-2) to treat ultrafiltration effluent of an actual landfill leachate, and quantitatively assessed the toxicities of the dominant chlorinated byproducts in EAOP-treated effluent. Considering both toxic effect and dose, it followed the order: active chlorine > chlorate > perchlorate > organochlorines. The toxic active chlorine could spontaneously decompose by settling. And secondary bioreactor originally serving for denitrification could be used to reduce perchlorate and chlorate. The effects of residual active chlorine and extra carbon addition on simultaneous denitrification, perchlorate, and chlorate reduction were investigated. It seemed that 20 mg of active chlorine was an acceptable level to bioactivity, and sufficient electron donors favored the removal of chlorate and perchlorate. Pseudomonas was identified as an active chlorine tolerant chlorate-reducing bacteria. And Thauera was responsible for perchlorate reduction under the conditions of sufficient carbon source supply. Our results confirmed that the perchlorate and chlorate concentrations in the effluent below their health advisory levels were achievable, solving the issue of toxic chlorinated byproduct generation during EAOP. This study provided a solution to realistic application of EAOP to treat high chloride wastewater.


Assuntos
Poluentes Químicos da Água , Cloro , Cloretos , Percloratos , Cloratos , Oxirredução , Carbono
5.
Sci Total Environ ; 861: 160566, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36574544

RESUMO

Perchlorate, nitrate, and thiocyanate are common thyroid disruptors in daily life and alter testosterone levels in animals. However, little is known about the effects of perchlorate, nitrate, and thiocyanate on serum total testosterone (TT) in the general population. The study was designed to assess the associations between urinary levels of perchlorate, nitrate, and thiocyanate and serum total testosterone (TT) in the general population. The present study utilized data from the 2011-2016 National Health and Nutritional Examination Survey (NHANES). A total of 6201 participants aged 6-79 with information on urinary perchlorate, nitrate, thiocyanate, and serum total testosterone were included. We conducted multiple linear regression models and Bayesian Kernel Machine Regression (BKMR) models to estimate the associations by sex-age groups. Children (ages 6-11) have higher levels of perchlorate and nitrate than the rest. After adjusting for covariates, urinary perchlorate was significantly negatively associated with serum TT in male adolescents (ß = -0.1, 95 % confidence interval: -0.2, -0.01) and female children [-0.13, (-0.21, -0.05)]. Urinary nitrate was significantly negatively associated with serum TT in female children, while urinary thiocyanate was significantly positively associated with serum TT in female adults aged 20 to 49 [0.05 (0.02, 0.08)]. BKMR analysis indicated that no other interactions were found between urinary perchlorate, nitrate, and thiocyanate. Our findings suggested that urinary perchlorate, nitrate, and thiocyanate levels may relate to serum total testosterone levels in specific sex-age groups. We identified male adolescents and female children as are most sensitive subgroups where testosterone is susceptible to interference.


Assuntos
Nitratos , Tiocianatos , Humanos , Masculino , Feminino , Criança , Nitratos/urina , Tiocianatos/urina , Percloratos , Inquéritos Nutricionais , Teorema de Bayes , Testosterona
6.
Food Chem ; 398: 133864, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35969996

RESUMO

The ability of bovine κ-casein-derived caseinomacropeptide (CMP) to exert bioactivity in the human gut depends on its digestive survival. Sampling from the human jejunum after feeding CMP and top-down glycopeptidomics analysis facilitates the determination of CMP survival. To reduce interference from non-target molecules in mass spectrometric analysis, CMP must be isolated from digestive fluid. To identify an optimal extraction method, this study compared the profiles of CMP extracted from feeding material (commercial CMP in water) and digestive fluid by ethanol precipitation, perchloric acid (PCA) precipitation, and ultrafiltration. Ethanol precipitation yielded the highest ion abundances for aglycosylated CMP and glycosylated CMP in both feeding material and jejunal samples. Notably, PCA precipitation yielded the highest abundance of partially digested CMP-derived fragments in jejunal samples. Overall, ethanol precipitation was the most effective among the methods tested for intact CMP extraction from jejunal fluids, whereas PCA precipitation was optimal for extraction of CMP fragments.


Assuntos
Caseínas , Jejuno , Animais , Bovinos , Humanos , Caseínas/química , Etanol , Fragmentos de Peptídeos , Percloratos , Ultrafiltração
7.
Molecules ; 27(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500539

RESUMO

A convenient method to access the above perchlorates has been developed, based on the cyclocondensation of 3-aminofurazans with 1,3-diketones in the presence of HClO4. All compounds were fully characterized by multinuclear NMR spectroscopy and X-ray crystal structure determinations. Initial safety testing (impact and friction sensitivity) and thermal stability measurements (DSC/DTA) were also carried out. Energetic performance was calculated by using the PILEM code based on calculated enthalpies of formation and experimental densities at r.t. These salts exhibit excellent burn rates and combustion behavior and are promising ingredients for energetic materials.


Assuntos
Antitireóideos , Percloratos , Fricção , Cetonas , Ressonância Magnética Nuclear Biomolecular
8.
Water Res ; 227: 119343, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36371918

RESUMO

Perchlorate is a widely detected environmental contaminant in surface and underground water, that seriously impacts human health by inhibiting the uptake of thyroidal radioiodine. Perchlorate reduction due to saline lake microorganisms is not as well understood as that in marine environments. In this study, we enriched a perchlorate-reducing microbial consortium collected from saline lake sediments and found that the perchlorate reduction kinetics of the enriched consortium fit the Michaelis-Menten kinetics well, with a maximum specific substrate reduction rate (qmax) of 0.596 ± 0.001 mg ClO4-/mg DW/h and half-saturation constant (Ks) of 16.549 ± 0.488 mg ClO4-/L. Furthermore, we used improved metagenome binning to reconstruct high-quality metagenome-assembled genomes from the metagenomes of the microbial consortia, including the perchlorate-reducing bacteria (PRB) Dechloromonas agitata and Wolinella succinogenes, with the genome of W. succinogenes harboring complete functional genes for perchlorate reduction being the first recovered. Given that the electrons were directly transferred to the electronic carrier cytochrome c-553 from the quinone pool, the electron transfer pathway of W. succinogenes was shorter and more efficient than the canonical pattern. This finding provides a theoretical basis for microbial remediation of sites contaminated by high concentrations of perchlorate. Metagenomic binning and metatranscriptomic analyses revealed the gene transcription variation of perchlorate reductase pcr and chlorite dismutase cld by PRB and the synergistic metabolic mechanism.


Assuntos
Lagos , Percloratos , Poluentes Químicos da Água , Humanos , Bactérias/genética , Bactérias/metabolismo , Radioisótopos do Iodo/metabolismo , Lagos/química , Metagenômica , Oxirredução , Percloratos/química , Percloratos/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação
9.
Front Endocrinol (Lausanne) ; 13: 995503, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339434

RESUMO

Thyroid disruptors are found in food, atmosphere, soil, and water. These contaminants interfere with the thyroid function through the impairment of thyroid hormone synthesis, plasma transport, peripheral metabolism, transport into the target cells, and thyroid hormone action. It is well known that iodide uptake mediated by the sodium-iodide symporter (NIS) is the first limiting step involved in thyroid hormones production. Therefore, it has been described that several thyroid disruptors interfere with the thyroid function through the regulation of NIS expression and/or activity. Perchlorate, nitrate, and thiocyanate competitively inhibit the NIS-mediated iodide uptake. These contaminants are mainly found in food, water and in the smoke of cigarettes. Although the impact of the human exposure to these anions is highly controversial, some studies indicated their deleterious effects in the thyroid function, especially in individuals living in iodine deficient areas. Considering the critical role of thyroid function and the production of thyroid hormones for growth, metabolism, and development, this review summarizes the impact of the exposure to these NIS-inhibitors on thyroid function and their consequences for human health.


Assuntos
Poluentes Ambientais , Percloratos , Humanos , Percloratos/toxicidade , Percloratos/metabolismo , Tiocianatos/metabolismo , Tiocianatos/farmacologia , Nitratos/metabolismo , Nitratos/farmacologia , Glândula Tireoide/metabolismo , Poluentes Ambientais/metabolismo , Iodetos/metabolismo , Iodetos/farmacologia , Hormônios Tireóideos , Água/metabolismo
10.
New Dir Child Adolesc Dev ; 2022(185-186): 107-122, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36251327

RESUMO

The association of overweight/obesity, and central obesity with thiocyanate (SCN), perchlorate (CIO), and nitrate (NO) in childhood and adolescence is unclear. Therefore, this study aimed to explore this association in 4447 participants comprising children and adolescents (aged 6-19 years) using data from the United States National Health and Nutrition Examination Survey 2005-2016. SCN level was positively associated with overweight/obesity in both children and adolescents, while CIO level was negatively associated with overweight/obesity only in children; however, no significant association was found for NO level. Similar associations were found between SCN level and central obesity. Thus, our results suggest that SCN exposure was associated with overweight/obesity and central obesity in both children and adolescents, while a negative association was observed for CIO in children. Strategies to monitor the exposure levels and the mechanisms underlying the relationship between exposure and the weight parameters are recommended.


Assuntos
Percloratos , Tiocianatos , Criança , Adolescente , Estados Unidos/epidemiologia , Humanos , Inquéritos Nutricionais , Nitratos/efeitos adversos , Sobrepeso/epidemiologia , Obesidade Abdominal , Exposição Ambiental , Obesidade
11.
Artigo em Inglês | MEDLINE | ID: mdl-36294032

RESUMO

Additives are defined as substances added to food with the aim of preserving and improving safety, freshness, taste, texture, or appearance. While indirect additives can be found in traces in food and come from materials used for packaging, storage, and technological processing of food, direct additives are added to food with a special purpose (canning). The use of additives is justified if it is in accordance with legal regulations and does not pose a health or danger to consumers in the prescribed concentration. However, due to the specificity of the child's metabolic system, there is a greater risk that the negative effects of the additive will manifest. Considering the importance of the potential negative impact of additives on children's health and the increased interest in the control and monitoring of additives in food for children, we have reviewed the latest available literature available through PubMed, Scopus, and Google Scholar. Expert data were taken from publicly available documents published from January 2010 to April 2022 by internationally recognized professional organizations. It was found that the most frequently present additives in the food consumed by children are bisphenols, phthalates, perfluoroalkyl chemicals, perchlorates, pesticides, nitrates and nitrites, artificial food colors, monosodium glutamate, and aspartame. Increasing literacy about the presence and potential risk through continuous education of parents and young people as well as active monitoring of newly registered additives and harmonization of existing legal regulations by competent authorities can significantly prevent the unwanted effects of additives on children's health.


Assuntos
Fluorcarbonetos , Praguicidas , Criança , Humanos , Adolescente , Aditivos Alimentares , Nitritos , Aspartame , Glutamato de Sódio , Percloratos
12.
Analyst ; 147(22): 5075-5081, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36217718

RESUMO

A qQNMR methodology using chlorine-35 as the employed quadrupolar nucleus has been introduced for the first time as a robust and validated method to determine and quantify perchlorate in epoxy resins. The quantification has been carried out by using a calibration curve of lithium perchlorate. The method was validated at seven concentration levels in the range of 0.16 to 2.0 mg mL-1 (1.6 to 20 mM in perchlorate), affording intra- and inter-day accuracies lower than 0.66% (expressed in CV), robustness towards pH, temperature, resin concentration and recycle delay, a limit of detection (LOD) of 0.08 mg mL-1 (0.8 mM in perchlorate), a limit of quantification (LOQ) of 0.16 mg mL-1 (1.6 mM in perchlorate) and probably most important in such applications, having no matrix effect. The method was applied on epoxy resins containing three different types of perchlorate precursors (lithium, potassium and tetramethylammonium), affording excellent quantifications with relative errors below 2.3% compared to the spiked concentrations.


Assuntos
Cloro , Percloratos , Percloratos/química , Resinas Epóxi , Limite de Detecção
13.
Sci Rep ; 12(1): 15880, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36151096

RESUMO

Formation of chlorate (ClO3-) and perchlorate (ClO4-) as by-products in electrooxidation process has raised concern. In the present study, the formation of ClO3- and ClO4- in the presence of 1.0 mM Cl- on boron doped diamond (BDD) and Magneli phase titanium suboxide (Ti4O7) anodes were evaluated. The Cl- was transformed to ClO3- (temporal maximum 276.2 µM) in the first 0.5 h on BDD anodes with a constant current density of 10 mA cm2, while approximately 1000 µM ClO4- was formed after 4.0 h. The formation of ClO3- on the Ti4O7 anode was slower, reaching a temporary maximum of approximately 350.6 µM in 4.0 h, and the formation of ClO4- was also slower on the Ti4O7 anode, taking 8.0 h to reach 780.0 µM. Compared with the BDD anode, the rate of ClO3- and ClO4- formation on the Ti4O7 anode were always slower, regardless of the supporting electrolytes used in the experiments, including Na2SO4, NaNO3, Na2B4O7, and Na2HPO4. It is interesting that the formation of ClO4- during electrooxidation was largely mitigated or even eliminated, when methanol, KI, and H2O2 were included in the reaction solutions. The mechanism of the inhibition on Cl- transformation by electrooxidation was explored.


Assuntos
Percloratos , Poluentes Químicos da Água , Boro , Cloratos , Diamante , Eletrodos , Peróxido de Hidrogênio , Metanol , Oxirredução , Titânio/farmacologia , Poluentes Químicos da Água/análise
14.
Se Pu ; 40(9): 825-832, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-36156629

RESUMO

Eriocheir sinensis is a unique freshwater crab found in China, which is well known for its rich nutrition and sweet and delicious taste. Free amino acids in Eriocheir sinensis are not only important nutrients but also are closely related to their unique taste and aroma. Therefore, the determination of the free amino acid contents in Eriocheir sinensis is of great significance for product quality evaluation, flavor research, authenticity, and origin identification. Herein we proposed an ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS)-based method for the determination of 17 free amino acids in Eriocheir sinensis. First, 5 g of the Eriocheir sinensis sample was weighed into a 50-mL polypropylene centrifuge tube. Then, 10 mL of extraction solvents was added to the centrifuge tube, and the resultant solution was mixed well using a vortex mixer. We compared a variety of solvents and finally selected 5%(v/v) perchloric acid aqueous solution as the optimum extraction solvent. The supernatant was transferred to another polypropylene centrifuge tube after centrifuging at 8000 r/min for 5 min. The extraction procedure was repeated according to the above-mentioned steps, and the extraction solution was combined with the supernatant. The extracts were then adjusted to pH 6.5 with 1 mol/L potassium hydroxide solution, and were diluted to 50 mL with water. After filtering by both qualitative filter paper and a 0.45-µm polyether sulfone syringe filter, the extracts were determined by UHPLC-HRMS. We compared three types of mobile phases and chose 0.1%(v/v) formic acid aqueous solution mixed with acetonitrile as the optimum one. Precise parent ion and ion source parameters were also optimized. The 17 analytes, viz. aspartic acid, threonine, serine, glutamic acid, proline, cystine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, lysine, arginine, glycine, alanine, and histidine, were separated on an XDB-C18 column (100 mm×4.6 mm, 1.7 µm) with gradient elution. The amino acids were then detected by HRMS in electrospray ionization and selected ion monitoring modes, and the analytes were quantified using external standards. The instrumental detection limit (IDL) and the instrumental quantification limit (IQL) were 0.3 mg/L and 1.0 mg/L, respectively. The linear correlation coefficients were all above 0.9990 in the concentration range of 10.0-200.0 mg/kg. Three levels of free amino acid standards were spiked into the edible parts of Eriocheir sinensis. The recoveries of the amino acids were between 78.4% and 105.3%. The intra-sample, intra-day, and inter-day repeatabilities were below 4.2%, 5.2%, and 11.4%, respectively, which were within reasonable ranges. Twenty samples of Eriocheir sinensis were tested using the proposed method. Thus, in this study, we developed an alternative method for the determination of free amino acids in Eriocheir sinensis with simple pretreatment, good selectivity, and high accuracy.


Assuntos
Braquiúros , Percloratos , Acetonitrilas , Alanina , Aminoácidos , Animais , Arginina , Ácido Aspártico , Cromatografia Líquida de Alta Pressão , Cistina , Formiatos , Glutamatos , Glicina , Histidina , Isoleucina , Leucina , Lisina , Espectrometria de Massas , Metionina , Fenilalanina , Polipropilenos , Prolina , Serina , Solventes , Treonina , Tirosina , Valina , Água
15.
Int J Mol Sci ; 23(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36142508

RESUMO

The biological reduction of slow degradation contaminants such as perchlorate (ClO4-) is considered to be a promising water treatment technology. The process is based on the ability of a specific mixed microbial culture to use perchlorate as an electron acceptor in the absence of oxygen. In this study, batch experiments were conducted to investigate the effect of nitrate on perchlorate reduction, the kinetic parameters of the Monod equation and the optimal ratio of acetate to perchlorate for the perchlorate reducing bacterial consortium. The results of this study suggest that acclimated microbial cultures can be applied to treat wastewater containing high concentrations of perchlorate. Reactor experiments were carried out with different hydraulic retention times (HRTs) to determine the optimal operating conditions. A fixed optimal HRT and the effect of nitrate on perchlorate reduction were investigated with various concentrations of the electron donor. The results showed that perchlorate reduction occurred after nitrate removal. Moreover, the presence of sulfate in wastewater had no effect on the perchlorate reduction. However, it had little effect on biomass concentration in the presence of nitrate during exposure to a mixed microbial culture, considering the nitrate as the inhibitor of perchlorate reduction by reducing the degradation rate. The batch scale experiment results illustrated that for efficient operation of perchlorate reduction, the optimal acetate to perchlorate ratio of 1.4:1.0 would be enough. Moreover, these experiments found the following results: the kinetic parameters equivalent to Y = 0.281 mg biomass/mg perchlorate, Ks = 37.619 mg/L and qmax = 0.042 mg perchlorate/mg biomass/h. In addition, anoxic-aerobic experimental reactor results verify the optimal HRT of 6 h for continuous application. Furthermore, it also illustrated that using 600 mg/L of acetate as a carbon source is responsible for 100% of nitrate reduction with less than 50% of the perchlorate reduction, whereas at 1000 mg/L acetate, approximately 100% reduction was recorded.


Assuntos
Nitratos , Percloratos , Acetatos/farmacologia , Reatores Biológicos/microbiologia , Carbono , Nitratos/metabolismo , Oxirredução , Oxigênio , Percloratos/metabolismo , Sulfatos/metabolismo , /microbiologia
16.
J Hazard Mater ; 439: 129629, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36104921

RESUMO

Perchlorate is an emerging pollutant and thyroid toxicant frequently occurred in air, water, soil and various foodstuffs. Rice and wheat flour are the most common staple foods, which could accumulate perchlorate from contaminated soils and irrigation water. However, human exposure to perchlorate via rice and wheat flour consumption has only been investigated to a limited extent. Therefore, we collected 207 rice samples and 189 wheat flour samples from 19 provinces in China to assess the level of perchlorate. The levels of perchlorate in rice and wheat flour ranged from not detected (N.D.) to 28.7 ng/g and less than limits of quantification (

Assuntos
Farinha , Oryza , Humanos , Percloratos , Medição de Risco , Triticum , Água
17.
Aquat Toxicol ; 251: 106283, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36063761

RESUMO

Perchlorate is a chemical compound commonly used in military artillery and equipment. It has been detected in drinking water, air, soil, and breast milk. Exposure of humans to perchlorate can occur in the theater of war and areas adjacent to military training grounds. A high concentration of perchlorate has been found to affect reproduction in vertebrates, including fish. However, whether environmental concentrations of perchlorate can affect primordial germ cells (PGCs), the founders of sperm and eggs, is not clearly understood. In the present study, we examined the effects of 0, 10, 100, and 1000 µg/L potassium perchlorate exposure on the embryonic development of medaka and their PGCs. Perchlorate exposure delayed hatching time, reduced heartbeat, inhibited migration of PGCs, and increased developmental deformities in the larvae. The 10 and 20 mg/L concentrations of perchlorate were lethal to embryos, whereas vitamin C co-treatment (1 mg/L) completely blocked perchlorate-induced mortality. RNA-seq analysis of isolated PGCs showed a non-linear pattern in expression profiles of differentially altered genes. Significantly upregulated genes were found in PGCs from the 10 and 1000 µg/L groups, whereas the 100 µg/L groups showed the highest number of significantly downregulated genes. Gene ontology analysis predicted differentially expressed genes to be involved in proteolysis, metabolic processes, peptides activity, hydrolase activity, and hormone activity. Among the cellular components, extracellular, intracellular, sarcoplasmic, and 6-phosphofructokinase and membrane-bounded processes were affected. Ingenuity Pathway Analysis of PGC transcriptomes revealed thyroid hormone signaling to be affected by all concentrations of perchlorate. The present results suggested that perchlorate affected the development of medaka larvae and vitamin C was able to ameliorate perchlorate-induced embryo mortality. Additionally, perchlorate altered the global transcriptional network in PGCs in a non-linear fashion suggesting its potential effects on developing germ cells and fertility.


Assuntos
Água Potável , Oryzias , Poluentes Químicos da Água , Animais , Ácido Ascórbico/metabolismo , Água Potável/metabolismo , Feminino , Células Germinativas/metabolismo , Hormônios/metabolismo , Humanos , Hidrolases/metabolismo , Larva , Masculino , Oryzias/genética , Percloratos/metabolismo , Percloratos/toxicidade , Compostos de Potássio , Sêmen , Solo , Poluentes Químicos da Água/toxicidade
18.
BMC Geriatr ; 22(1): 740, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096772

RESUMO

BACKGROUND & AIMS: Aging is a pathophysiological process driven by a diverse set of complex biological processes, and environmental pollution plays an important role in this process. This study aimed to explore the association between serum α-Klotho levels and urinary perchlorate, nitrate, and thiocyanate levels. METHODS: This secondary dataset analysis included 4875 participants (mean age, 57.69 year; male, 49.58%; non-Hispanic White, 47.67%) from the US National Health and Nutrition Examination Survey (2007-2014). Enzyme-linked immunosorbent assay was used to quantify α-Klotho levels, and ion chromatography coupled with electrospray tandem mass spectrometry was used to quantify thiocyanate, nitrate, and perchlorate levels. Multivariate linear regression models were applied to estimate the association between perchlorate, nitrate, and thiocyanate levels and serum α-Klotho levels. RESULTS: Urinary thiocyanate levels were negatively associated with α-Klotho levels (ß = - 0.006; 95% confidence interval, - 0.010 to - 0.003; P = 0.0004) after adjusting for age, sex, body mass index, race, alcohol consumption, estimated glomerular filtration rate, underlying disease, physical activity, smoking status, usual energy intake, and urinary creatinine and serum cotinine levels and mutual adjustment of urinary perchlorate, urinary nitrate, and urinary thiocyanate levels. The α-Klotho level in participants in the highest quartile was higher by 50.567 ng/mL (ß = 50.567; 95% confidence interval, 14.407 to 86.726; P = 0.009) than that in participants in the lowest quartile of urinary perchlorate. A linear relationship was observed between urinary thiocyanate and α-Klotho levels. CONCLUSIONS: Urinary thiocyanate levels were negatively associated with serum α-Klotho levels. Urinary thiocyanate should be further investigated as a potential mediator of aging and age-related diseases.


Assuntos
Percloratos , Tiocianatos , Exposição Ambiental/efeitos adversos , Humanos , Masculino , Nitratos/urina , Inquéritos Nutricionais , Percloratos/urina , Tiocianatos/urina
19.
J Phys Chem B ; 126(39): 7701-7708, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36166380

RESUMO

Experiments have shown that in the presence of electrolytes, the hydrated electron's absorption spectrum experiences a blue shift whose magnitude depends on both the salt concentration and chemical identity. Previous computer simulations have suggested that the spectral blue shift results from the formation of (cation, electron) contact pairs and that the concentration dependence arises because the number of cations simultaneously paired with the electron increases with increasing concentration. In this work, we perform new simulations to build an atomistic picture that explains the effect of salt identity on the observed hydrated electron spectral shifts. We simulate hydrated electrons in the presence of both monovalent (Na+) and divalent (Ca2+) cations paired with both Cl- and a spherical species representing ClO4- anions. Our simulations reproduce the experimental observations that divalent ions produce larger blue shifts of the hydrated electron's spectrum than monovalent ions with the same anion and that perchlorate salts show enhanced blue shifts compared to chloride salts with the same cation. We find that these observations can be explained by competitive ion pairing. With small kosmotropic cations such as Na+ and Ca2+, aqueous chloride salts tend to form (cation, anion) contact pairs, whereas there is little ion pairing between these cations and chaotropic perchlorate anions. Hydrated electrons also strongly interact with these cations, but if the cations are also paired with anions, this affects the free energy of the electron-cation interaction. With chloride salts, hydrated electrons end up in complexes containing multiple cations plus a few anions as well as the electron. Repulsive interactions between the electron and the nearby Cl- anions reduce the cation-induced spectral blue shift of the hydrated electron. With perchlorate salts, hydrated electrons pair with multiple cations without any associated anions, leading to the largest possible cation-induced spectral blue shift. We also see that the reason multivalent cations produce larger spectral blue shifts than monovalent cations is because hydrated electrons are able to simultaneously pair with a larger number of multivalent cations due to a larger free energy of interaction. Overall, the interaction of hydrated electrons with electrolytes fits well with the Hofmeister series, where the electron behaves as an anion that is slightly more able to break water's H-bond structure than chloride.


Assuntos
Elétrons , Percloratos , Ânions/química , Cátions/química , Cátions Monovalentes , Cloretos/química , Eletrólitos , Sais , Sódio , Água
20.
Environ Microbiol ; 24(11): 5051-5065, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35920032

RESUMO

If life exists on Mars, it would face several challenges including the presence of perchlorates, which destabilize biomacromolecules by inducing chaotropic stress. However, little is known about perchlorate toxicity for microorganisms on the cellular level. Here, we present the first proteomic investigation on the perchlorate-specific stress responses of the halotolerant yeast Debaryomyces hansenii and compare these to generally known salt stress adaptations. We found that the responses to NaCl and NaClO4 -induced stresses share many common metabolic features, for example, signalling pathways, elevated energy metabolism, or osmolyte biosynthesis. Nevertheless, several new perchlorate-specific stress responses could be identified, such as protein glycosylation and cell wall remodulations, presumably in order to stabilize protein structures and the cell envelope. These stress responses would also be relevant for putative life on Mars, which-given the environmental conditions-likely developed chaotropic defence strategies such as stabilized confirmations of biomacromolecules or the formation of cell clusters.


Assuntos
Debaryomyces , Marte , Percloratos/metabolismo , Meio Ambiente Extraterreno , Proteômica
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