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1.
Sci Total Environ ; 856(Pt 2): 159130, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36183771

RESUMO

A multi-omics approach was utilized to identify altered biological responses and functions, and to prioritize contaminants to assess the risks of chemical mixtures in the Maumee Area of Concern (AOC), Maumee River, OH, USA. The Maumee AOC is designated by the United States Environmental Protection Agency as having significant beneficial use impairments, including degradation of fish and wildlife populations, bird or animal deformities or reproduction problems, and loss of fish and wildlife habitat. Tree swallow (Tachycineta bicolor) nestlings were collected at five sites along the Maumee River, which included wastewater treatment plants (WWTPs) and industrial land-use sites. Polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo p dioxins and furans (PCDD/Fs), and chlorinated pesticide concentrations were elevated in Maumee tree swallows, relative to a remote reference site, Star Lake, WI, USA. Liver tissue was utilized for non-targeted transcriptome and targeted metabolome evaluation. A significantly differentially expressed gene cluster related to a downregulation in cell growth and cell cycle regulation was identified when comparing all Maumee River sites with the reference site. There was an upregulation of lipogenesis genes, such as PPAR signaling (HMGCS2, SLC22A5), biosynthesis of unsaturated fatty acids (FASN, SCD, ELOVL2, and FADS2), and higher lipogenesis related metabolites, such as docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and arachidonic acid (AA) at two industrial land-use sites, Ironhead and Maumee, relative to WWTP sites (Perrysburg and SideCut), and the reference site. Toledo Water, in the vicinity of the other two industrial sites and also adjacent to a WWTP, showed a mix of signals between industrial land-use and WWTP land-use. PAHs, oxychlordane, and PBDEs were determined to be the most likely causes of the differentiation in biological responses, including de novo lipogenesis and biosynthesis of unsaturated fatty acids.


Assuntos
Bifenilos Policlorados , Dibenzodioxinas Policloradas , Hidrocarbonetos Policíclicos Aromáticos , Andorinhas , Animais , Éteres Difenil Halogenados/análise , Ohio , Dibenzofuranos/metabolismo , Monitoramento Ambiental , Dibenzodioxinas Policloradas/metabolismo , Reprodução , Andorinhas/metabolismo , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
2.
J Environ Sci (China) ; 125: 742-749, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36375956

RESUMO

The concentrations and distributions of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) in the whole blood and meat of eight typical edible animals (chicken, donkey, horse, cattle, rabbit, sheep, duck, and pig) were illustrated. Total concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and PCBs (on a basis of liquid volume) in animal bloods were 142-484 pg/L and 46-62 ng/L, respectively. Total concentrations of PCDD/Fs and PCBs (on a basis of dry weight (dw) and lipid weight (lw)) in animal meat samples were 0.47-1090 pg/g dw (0.47-4513 pg/g lw) and 7.2-23 ng/g dw (10-776 ng/g lw), respectively. TEQs for both PCDD/Fs and PCBs in animal blood and meat samples were (67 ± 27) pg/L and (5.3 ± 14) pg/g dw (24 ± 56 pg/g lw), respectively. Besides, the dietary intakes of PCDD/Fs and PCBs were also estimated. Chicken and pig contributed more TEQs than other animals. Chicken contributed the most (95%) with high toxicity, followed by pig (3.4%) with high consumption. The dietary intake of chicken might pose risks to consumers who prefer to eat chicken products, who should comprehensively consider the essential nutrients and contaminants in food during dietary intake.


Assuntos
Benzofuranos , Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Bovinos , Suínos , Ovinos , Coelhos , Cavalos , Animais , Dibenzodioxinas Policloradas/análise , Bifenilos Policlorados/análise , Dibenzofuranos , Benzofuranos/análise , Dibenzofuranos Policlorados/análise , Carne , Contaminação de Alimentos/análise , Dioxinas/análise
3.
Sci Total Environ ; 857(Pt 2): 159551, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36265614

RESUMO

The application of the 3T method during combustion (i.e., a Temperature > 850 °C, a residence Time > 2 s, and sufficient Turbulence) can lead to elevated operating temperature in the baghouse filter for the municipal solid waste incineration (MSWI) systems without sufficient heat exchange capacity, which is potentially detrimental to the emission control of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Herein, a field study focusing on the distribution and variation of PCDD/Fs in gaseous and solid phases in a baghouse filter with high operating temperature (225-230 °C) was carried out. The concentration of PCDD/Fs in gases at the outlet of the baghouse filter was around 1 order of magnitude higher than that in inlet gases (i.e., noticeable memory effect of PCDD/Fs), because of the significant PCDD/Fs formation in filter fly ash (primarily contributed by the precursor pathway) followed by PCDD/Fs desorption. In addition, the mechanisms and factors resulting in the memory effect of PCDD/Fs were identified based on a laboratory study that carefully investigated the formation and desorption of PCDD/Fs at potential operating temperatures of baghouse filters (i.e., 180, 200, and 225 °C). The temperature was identified as the key factor inducing the memory effect of PCDD/Fs, because: i) PCDD/Fs memory effect was not observed for baghouse filters with low operating temperatures of ~150 °C in previous studies; ii) both the formation and desorption of PCDD/Fs were noticeably favored by rising temperature from 180 to 225 °C; iii) increasing temperature appeared to facilitate the transformation from inorganic Cl to organic Cl and the conversion from aliphatic carbon to aromatic carbon or unsaturated hydrocarbons, both of which were favorable to PCDD/Fs formation; and iv) the release rate of PCDD/Fs from fly ash was exponentially dependent on temperature based on the modeling results of reaction kinetics.


Assuntos
Benzofuranos , Dibenzodioxinas Policloradas , Dibenzodioxinas Policloradas/análise , Cinza de Carvão , Dibenzofuranos , Temperatura , Temperatura Alta , Incineração , Gases , Carbono , Dibenzofuranos Policlorados
4.
Chemosphere ; 310: 136723, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36241106

RESUMO

Dioxin and dioxin-like compounds are ubiquitous environmental contaminants that induce toxicity by binding to the aryl hydrocarbon receptor (AHR), a ligand activated transcription factor. The zebrafish model has been used to define the developmental toxicity observed following exposure to exogenous AHR ligands such as the potent agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin, TCDD). While the model has successfully identified cellular targets of TCDD and molecular mechanisms mediating TCDD-induced phenotypes, fundamental information such as the body burden produced by standard exposure models is still unknown. We performed targeted gas chromatography (GC) high-resolution mass spectrometry (HRMS) in tandem with non-targeted liquid chromatography (LC) HRMS to quantify TCDD uptake, model the elimination dynamics of TCDD, and determine how TCDD exposure affects the zebrafish metabolome. We found that 50 ppt, 10 ppb, and 1 ppb waterborne exposures to TCDD during early embryogenesis produced environmentally relevant body burdens: 38 ± 4.34, 26.6 ± 1.2, and 8.53 ± 0.341 pg/embryo, respectively, at 24 hours post fertilization. TCDD exposure was associated with the dysregulation of metabolic pathways that are associated with the AHR signaling pathway as well as pathways shown to be affected in mammals following TCDD exposure. In addition, we discovered that TCDD exposure affected several metabolic pathways that are critical for brain development and function including glutamate metabolism, chondroitin sulfate biosynthesis, and tyrosine metabolism. Together, these data demonstrate that existing exposure methods produce environmentally relevant body burdens of TCDD in zebrafish and provide insight into the biochemical pathways impacted by toxicant-induced AHR activation.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Animais , Dibenzodioxinas Policloradas/metabolismo , Peixe-Zebra/metabolismo , Dioxinas/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Proteínas de Peixe-Zebra/genética , Transdução de Sinais , Mamíferos/metabolismo
5.
Int J Mol Sci ; 23(21)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36361507

RESUMO

Given the importance of breastfeeding infants, the contamination of human milk is a significant public concern. The aim of this study was to assess the contamination of human milk with dioxin-like PCBs (dl-PCBs) and non-dioxin-like PCBs (ndl-PCBs) in relation to the duration of lactation and other influencing factors, especially the frequency of the consumption of selected foods during pregnancy. Based on this, the health risk to infants was assessed and compared to the tolerable daily intake (TDI). PCB determinations were performed using gas chromatography/mass spectrometry. The ∑ndl-PCB content ranged from 0.008 to 0.897 ng/g w.w., at an average of 0.552 ng/g wet weight, which was 55% of the maximum level according to the EU guidelines for foods for infants and young children. The toxic equivalent (TEQ) was in the range of 0.033-5.67 pg-TEQ/g w.w. The content of non-ortho, mono-ortho, and ndl-PCBs in human milk decreased the longer lactation continued. Moreover, when pregnant women smoked tobacco, this correlated significantly with increases in the concentrations of PCB congeners 156, 118, and 189 in human milk. The human milk contents of PCB congeners 77, 81, 186, 118, and 189 were strongly positively correlated with the amount of fish consumed. The content of stable congeners PCB 135 and PCB 153 increased with age.


Assuntos
Benzofuranos , Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Lactente , Criança , Animais , Feminino , Humanos , Gravidez , Pré-Escolar , Aleitamento Materno , Benzofuranos/química , Lactação , Leite Humano/química , Medição de Risco , Contaminação de Alimentos/análise
6.
Artigo em Inglês | MEDLINE | ID: mdl-36360663

RESUMO

Pulse pressure (PP) is the difference between systolic blood pressure (SBP) and diastolic blood pressure (DBP), and an independent predictor of cardiovascular risk. Previous research suggests, with different conclusions, that exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) could affect blood pressure (BP). We conducted a cross-sectional study to determine the association of dioxin exposure with PP in early pregnancy. A total of 305 pregnant women in early pregnancy in Yingcheng, China, recruited from May 2018 to February 2021, were included in this study. We measured 17 congeners of PCDD/Fs in maternal serum via high-resolution gas chromatography tandem high-resolution mass spectrometry. A generalized linear regression model was used to analyze the influencing factors of dioxin exposure and their relationships with PP. The levels of total PCDD/Fs (∑PCDD/Fs) ranged from 163.52 pg/g lipid to 1,513,949.52 pg/g lipid, with a mean of 10,474.22 pg/g lipid. The mean toxicity equivalent (TEQ) of total PCDD/Fs (∑TEQ-PCDD/Fs) was 42.03 pg/g lipid. The ratio of tetrachlorinated to octa-chlorinated congeners in maternal serum was enriched with an increasing number of chlorines. Pregnant women with college and above education had higher concentrations of ∑PCDD/Fs than those with education levels of junior high school and below (ß = 0.34, 95% CI: 0.01, 0.67). The adjusted model for ∑TEQ-PCDD/Fs was significantly and negatively associated with PP (ß = -1.79, 95% CI: -2.91, -0.68). High levels of dioxins were found in this area, and exposure to dioxins may affect the PP of women in early pregnancy, with health risks.


Assuntos
Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Feminino , Humanos , Gravidez , Dioxinas/análise , Dibenzofuranos Policlorados , Estudos Transversais , Pressão Sanguínea , Dibenzofuranos , Cromatografia Gasosa-Espectrometria de Massas , Lipídeos , Bifenilos Policlorados/análise
7.
Ecotoxicol Environ Saf ; 247: 114227, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306615

RESUMO

World Health Organization toxic equivalency factors (WHO-TEFs) are recommended for risk management of brominated dioxins in aquatic environments because limited information is available on their toxicity to fish. To validate this approach, we obtained the relative potencies of polybrominated dibenzo-p-dioxins and polybrominated dibenzofurans and mixed-halogenated furans (PXDF, X = Cl/Br) against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) based on their toxicity to the early-life stage of Japanese medaka (Oryzias latipes). 2,3,7,8-substituted brominated dibenzofurans caused typical dioxin exposure effects, such as blue-sac disease. The TCDD-relative potency factors (REPs) of test substances were calculated based on the concentrations in water and eggs that caused 20% lethality on day 28 post-fertilization, and were in the order of: 2-chloro-3,7,8-tribromodibenzofuran (REPwater 3.3, REPegg 4.6) > 2,3,7,8-tetrabromodibenzofuran (0.85, 0.92) > 2,3,4,7,8-pentabromodibenzofuran (0.053, 0.55) > 1,2,3,7,8-pentabromodibenzofuran (0.0091, 0.19). The transfer rate from water to eggs was lower for pentabrominated furans than tetrabrominated congeners, and was expected to decrease with the log Kow of the test substance. Although the REPegg value can be used to compare the toxicity potential of brominated dioxins, REPwater may be more suitable for environmental risk assessment because the uptake potential of these compounds from water should be considered. This study is the first to report higher toxicity of a PXDF congener compared with TCDD in vivo, further investigations of the toxicity of mixed-halogenated dioxins and environmental behavior are necessary for environmental risk assessment.


Assuntos
Dioxinas , Oryzias , Dibenzodioxinas Policloradas , Animais , Dioxinas/toxicidade , Dibenzodioxinas Policloradas/toxicidade , Dibenzofuranos , Medição de Risco , Furanos , Água
8.
J Food Sci ; 87(11): 5142-5152, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36226778

RESUMO

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in various foods continuously concern the public. Pork and its byproducts, especially from Yorkshire pigs, are the largest meat food consumed by the general population in China. This study aims to investigate the distribution of PCDD/Fs in different tissues of Yorkshire pigs to understand their bioaccumulation. Yorkshire pigs were fed a known amount of PCDD/Fs through fly ash. PCDD/Fs were determined by isotope dilution method with a gas chromatography-high resolution mass spectrometer. The liver had the highest concentration levels (2041.33 pg/g lipid) and toxic equivalents values (69.14 pg/g lipid), followed by the spleen and lung, and the lowest ones in the brain. The liver also had the highest bioaccumulation of PCDD/Fs, and this level was considerably higher than that of other tissues. This study showed a strong accumulation capacity of the liver for polychlorinated dibenzo-p-dioxins and dibenzofurans under short-term exposure conditions, suggesting that the liver is a more sensitive tissue for monitoring PCDD/Fs in food safety risk monitoring. PRACTICAL APPLICATION: This paper may help the consumer in making food choices to minimize the exposure risk to Polychlorinated dibenzo-p-dioxins and dibenzofurans.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Animais , Humanos , Suínos , Dibenzofuranos , Dibenzofuranos Policlorados , Bioacumulação , Lipídeos
9.
Biomater Sci ; 10(22): 6583-6600, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36227002

RESUMO

Due to the complex bloodstream components, tumor microenvironment and tumor heterogeneity, traditional nanoparticles have a limited effect (low drug delivery efficiency and poor penetration to the deeper tumor) on eradicating tumors. To solve these challenges, novel platelet membrane-coated nanoparticles (PCDD NPs) were constructed for combined chemo-photodynamic- and immunotherapy of melanoma. The platelet membrane imparted the PCDD nanoparticles with an excellent long circulation effect and tumor targeting ability, which solved the issues of low drug delivery efficiency. After reaching the tumor cells, it releases the drug-loaded CDD micelles, becoming positively charged and facilitating the deep penetration of tumors. Cytotoxic and apoptosis experiments showed that PCDD nanoparticles have the strongest tumor cell killing ability. Based on the excellent results in vitro, PCDD was used to assess anti-tumor and distal tumor inhibition in rat models. The results revealed that the PCDD combined PDT, immunotherapy and chemotherapy could not only inhibit the primary tumor growth (inhibition rate: 92.0%) but also suppress the distant tumor growth (inhibition rate: 90.7%) and lung metastasis, which is far more effective compared to the commercial Taxotere®. Exploration of the molecular mechanism showed that in vivo immune response induced an increase in positive immune responders, suppressed negative immune suppressors, and established an inflammatory tumor immune environment, leading to excellent results in tumor suppression and lung metastasis. In conclusion, this novel multifunctional PCDD nanoparticle is a promising platform for tumor combined chemotherapy, photodynamic therapy (PDT) and immunotherapy.


Assuntos
Neoplasias Pulmonares , Nanopartículas , Fotoquimioterapia , Dibenzodioxinas Policloradas , Animais , Ratos , Espécies Reativas de Oxigênio , Biomimética , Linhagem Celular Tumoral , Fotoquimioterapia/métodos , Imunoterapia/métodos , Neoplasias Pulmonares/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Microambiente Tumoral
10.
Chemosphere ; 309(Pt 2): 136639, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36183877

RESUMO

A municipal waste incinerator (MWI) in Zhejiang, China, operating since 2008 was completely reconstructed from 2016 to 2019. In 2013, we conducted a cross-sectional study of breastfeeding mothers living near the MWI. We evaluated the concentrations of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the mothers' breast milk and their infants' estimated daily intake (EDI). To investigate the temporal variations of these pollutants, we conducted a cross-sectional study of 29 mothers in 2019. We assessed the levels of 18 PCB congeners, 17 PCDD/F congeners, and 21 per- and polyfluoroalkyl substance (PFAS) congeners in breast milk and estimated the EDI. The mean total concentrations of PCDD/Fs (ΣPCDD/Fs) and PCBs (ΣPCBs) were 81.2 and 4.90 ng/g lipid, respectively, while the toxic equivalent quantity (TEQ) levels of ΣPCDD/Fs and dioxin-like PCBs (ΣDL-PCBs) were 2.7 and 1.4 pg WHO-TEQ/g lipid, respectively. Compared to our 2013 measurements, the mass concentrations of ΣPCDD/Fs and ΣPCBs decreased by 13% and 35%, respectively (3.361 vs. 2.915 pg/g wet weight [ww] and 269.1 vs. 175.0 pg/g ww, respectively). The TEQ-ΣPCDD/F levels decreased by 67% (0.241 vs. 0.080 pg/g ww), but the TEQ-ΣDL-PCB levels increased by 11% (0.046 vs. 0.051 pg WHO-TEQ/g ww). The median concentration of PFASs was 0.250 ng/mL, ranging from 0.151 to 0.833 ng/mL. The infants' mean EDI of total PCDD/Fs and DL-PCBs was 17.7 pg TEQ/kg body weight [bw], representing a 20% decline compared to 2013. The average EDI levels of PFOS, PFOA, and PFNA were 5.8, 17.9, and 1.7 ng/kg bw, respectively. A comprehensive comparison of the results with studies from around the world showed that the potential health risks posed by legacy PCDD/F and PCB pollutants were not as grave for mothers and infants living near this MWI, but the emerging PFAS pollutants represented a new cause for concern. MAIN FINDINGS: The potential health risks posed by legacy PCDD/F and PCB pollutants were not particularly serious for mothers and infants living near the MWI, but the emerging PFAS pollutants raised new concerns.


Assuntos
Dioxinas , Poluentes Ambientais , Fluorcarbonetos , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Lactente , Feminino , Humanos , Dibenzodioxinas Policloradas/análise , Bifenilos Policlorados/análise , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Aleitamento Materno , Dioxinas/análise , Estudos Transversais , Poluentes Ambientais/análise , Leite Humano/química , China , Lipídeos
11.
J Agric Food Chem ; 70(42): 13754-13764, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36241171

RESUMO

Non-dioxin-like polychlorinated biphenyls (ndl-PCBs) are a subclass of persistent bioaccumulative pollutants able to enter the food chain. Toxicokinetic models for the transfer of the six ndl-PCB congeners (PCBs 28, 52, 101, 138, 153, and 180) from contaminated feed and soil into chicken eggs and meat are presented. Three independent controlled feeding study datasets were used to estimate the model parameters and four studies for evaluating the model performance. The yolk deposition of ndl-PCBs is modeled in a novel way that mimics the physiology of yolk growth and development, resulting in improved prediction of the experimental data without introducing an ad hoc time delay between ovulation and oviposition. Using the models, the highest level of 2.4 µg/kg dry matter (DM) was calculated for the sum of ndl-PCBs in laying hen feed to ensure that the current maximum levels in meat and eggs (40 ng/g fat) will not be exceeded. It is also shown how this highest level in feed should be adapted in case soil, in addition to feed, is also a source of ndl-PCBs for free-range chickens.


Assuntos
Dioxinas , Poluentes Ambientais , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Animais , Feminino , Bifenilos Policlorados/toxicidade , Bifenilos Policlorados/análise , Dioxinas/análise , Galinhas , Solo , Toxicocinética , Contaminação de Alimentos/análise , Dibenzodioxinas Policloradas/análise , Ovos/análise , Poluentes Ambientais/toxicidade , Poluentes Ambientais/análise
12.
Artigo em Inglês | MEDLINE | ID: mdl-36232160

RESUMO

To evaluate the impact of the first cement kiln co-processing municipal wastes in northwest China on the surrounding environment, the concentrations of polychlorinated naphthalenes (PCNs), polychlorinated biphenyls (PCBs), and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were determined in 17 soil samples collected around the plant. The concentration ranges of PCNs, PCBs, and PCDD/Fs were 132-1288, 10.8-59.5, and 2.50-5.95 pg/g, and the ranges of toxic equivalents (TEQ) were 1.98-20.8, 2.36-48.0, and 73.2-418 fg/g, respectively. The concentrations of PCNs, PCBs, and PCDD/Fs in this study were generally lower than those in soil around municipal waste incinerators and industrial parks in other areas. An exponential function equation was applied for the relationship between the concentration of the target compounds and the distance from the cement kiln stack, the results showed that PCN and PCB concentrations declined with the increasing of distance from the stack. Furthermore, it was found that the effect of the cement kiln on surrounding soil contaminations with PCNs and PCBs was stronger than that of PCDD/Fs by comparing the PCN, PCB, and PCDD/F homologue profiles in the fly ash sample from the plant and soil samples at different distances. The total carcinogenic risks (CR) of PCNs, PCBs, and PCDD/Fs for children and adults in soil were 1.65 × 10-8-8.93 × 10-8 and 1.70 × 10-8-9.16 × 10-8, respectively, which was less than the risk threshold (CR = 1 × 10-6), and there was no health risk.


Assuntos
Bifenilos Policlorados , Dibenzodioxinas Policloradas , Adulto , Criança , China , Cinza de Carvão , Dibenzofuranos , Monitoramento Ambiental/métodos , Humanos , Naftalenos , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Carbonitrila de Pregnenolona , Solo
13.
J Cell Sci ; 135(20)2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36148682

RESUMO

The ligand-activated transcription factor aryl hydrocarbon receptor (AHR) regulates cellular detoxification, proliferation and immune evasion in a range of cell types and tissues, including cancer cells. In this study, we used RNA-sequencing to identify the signature of the AHR target genes regulated by the pollutant 2,3,7,8-tetrachlorodibenzodioxin (TCDD) and the endogenous ligand kynurenine (Kyn), a tryptophan-derived metabolite. This approach identified a signature of six genes (CYP1A1, ALDH1A3, ABCG2, ADGRF1 and SCIN) as commonly activated by endogenous or exogenous ligands of AHR in multiple colon cancer cell lines. Among these, the actin-severing protein scinderin (SCIN) was necessary for cell proliferation; SCIN downregulation limited cell proliferation and its expression increased it. SCIN expression was elevated in a subset of colon cancer patient samples, which also contained elevated ß-catenin levels. Remarkably, SCIN expression promoted nuclear translocation of ß-catenin and activates the WNT pathway. Our study identifies a new mechanism for adhesion-mediated signaling in which SCIN, likely via its ability to alter the actin cytoskeleton, facilitates the nuclear translocation of ß-catenin. This article has an associated First Person interview with the first authors of the paper.


Assuntos
Neoplasias do Colo , Poluentes Ambientais , Dibenzodioxinas Policloradas , Humanos , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Via de Sinalização Wnt/genética , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Ligantes , Cinurenina , Triptofano , Actinas/metabolismo , Neoplasias do Colo/genética , RNA
14.
Toxicol Appl Pharmacol ; 454: 116259, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36179859

RESUMO

Part of the mechanism by which 2,3,7.8-tetrachlorodibenzo-p-dioxin (TCDD) suppresses immune function involves induction of regulatory T cells and suppression of effector T cells. The goal of this project was to examine whether TCDD's suppression of effector T cells was due in part to inducing B regulatory cells (Bregs). TCDD's potential to increase the percentage and/or function of CD24+CD38+ B cells was assessed in response to lipopolysaccharide (LPS) + interleukin (IL)-4 in vitro and in a mild model of experimental autoimmune encephalomyelitis (EAE) in vivo. In vitro, TCDD did not consistently increase the percentage of CD19+CD24+CD38+ cells using splenocytes, purified B cells or bone marrow (BM) cells. However, TCDD increased IL-10 in all three culture preparations, and TCDD increased the percentage of CD5+CD24+CD38+ cells producing IL-10. In EAE, TCDD did not affect the percentage of the CD24+CD38+ cell population in CD19, B220 or CD5 B cells in splenocytes (SPLC), lymph nodes (LN) nor BM cells at end-stage disease. On the other hand, TCDD increased the CD19+CD24+CD38+ percentage in the spinal cord (SC) in EAE. Moreover, TCDD-treated B cells isolated from spleens or TCDD-treated BM cells in EAE mice modestly reduced the ability of naïve effector T cells to express interferon (IFN)-γ and tumor necrosis factor (TNF)-α. Together these data show that TCDD can induce regulatory functions in B cells, although it was not obvious simply by examining the expression of regulatory markers but by assessing function by cytokine production or mixed lymphocyte responses.


Assuntos
Encefalomielite Autoimune Experimental , Dibenzodioxinas Policloradas , Animais , Linfócitos B , Interferons , Interleucina-10 , Lipopolissacarídeos , Camundongos , Dibenzodioxinas Policloradas/toxicidade , Linfócitos T , Fator de Necrose Tumoral alfa/metabolismo
15.
Chemosphere ; 308(Pt 2): 136286, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36075367

RESUMO

The aim of this study was to evaluate the performance of gas chromatography (GC)-triple quadrupole mass spectrometry (QqQ, MS/MS) as an alternative to the standard GC-high resolution mass spectrometry (GC-HR/MS) for soils contaminated with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). GC-QqQ (MS/MS) using a dynamic multiple reaction monitoring (dMRM) mode was optimized for the quantitative analysis of 17 PCDD/Fs. A comparative study between GC-QqQ (MS/MS) and GC-HR/MS was carried out to validate the results of actual field soil samples. Although GC-HR/MS has excellent sensitivity and selectivity, the validation parameters obtained by GC-QqQ (MS/MS) also met the recommended criteria of the standard method. The results for total and I-TEQ (international toxic equivalent) value of the PCDD/F concentrations of over 86.0 pg/g and 4.3 pg I-TEQ/g, respectively, in actual field soil samples showed good agreement between the two methods, falling within ±25% relative difference. In consideration of the remediation goal (100 pg I-TEQ/g), GC-QqQ (MS/MS) can be an alternative cost-effective method for use in soil remediation research.


Assuntos
Benzofuranos , Dibenzodioxinas Policloradas , Benzofuranos/análise , Análise Custo-Benefício , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Furanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Dibenzodioxinas Policloradas/análise , Solo , Espectrometria de Massas em Tandem/métodos
16.
Environ Pollut ; 313: 120122, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36089147

RESUMO

Dioxins and dioxin-like polychlorinated biphenyls (dl-PCBs) in fish fillet counteract the health benefits of fish products. In this study, food waste was used as a protein alternative to replacing fishmeal commonly used in the commercial fish feed, aiming to cultivate Sabah grouper with acceptable levels of dioxins and dl-PCBs. The concentrations of dioxins and dl-PCBs, as well as the fish growth performance, were compared between the fish groups fed with food waste-based feed (FWBF) and commercial feed (Nanyu®, control). The results showed that the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) (1.22 pg/g dry weight (d.w.)) and non-ortho-dl-PCBs (13.0 pg/g d.w.) were significantly lower (p < 0.05) in the FWBF than in the control feed (commercial feed) (PCDDs: 2.35 pg/g d.w.; non-ortho-dl-PCBs: 27.2 pg/g d.w.). The growth performance of the fish group fed with the FWBF was comparable to that fed with the control feed. There were no significant differences between the WHO2005-TEQ values of different fish fillets (1.00, 1.11, and 1.10 pg WHO2005-TEQ/g d.w. for FWBF group, control feed group, and local market fish, respectively). Based on the guidelines provided by European Food Safety Authority (ESFA) and U.S. Environmental Protection Agency (USEPA), the fish fed with the FWBF were safe for human consumption (hazard index values: 0.284-0.522; cancer risk range: 2.59-2.97 × 10-5). The findings of this study suggest that food waste could serve as an alternative protein source for cultivating Sabah grouper with acceptable levels of dioxins and dl-PCBs.


Assuntos
Bass , Benzofuranos , Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Eliminação de Resíduos , Animais , Humanos , Malásia , Bifenilos Policlorados/análise , Alimentos Marinhos/análise , Estados Unidos
17.
Environ Pollut ; 312: 120083, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36064061

RESUMO

This study focused on the syngenetic control of polychlorinated-ρ-dibenzodioxins and dibenzofurans (PCDD/Fs) and heavy metals by field stabilization/solidification (S/S) treatment for municipal solid waste incineration fly ash (MSWIFA) and multi-step leachate treatment. Modified European Community Bureau of Reference (BCR) speciation analysis and risk assessment code (RAC) revealed the medium environment risk of Cd and Mn, indicating the necessity of S/S treatment for MSWIFA. S/S treatment significantly declined the mass/toxic concentrations of PCDD/Fs (i.e., from 7.21 to 4.25 µg/kg; from 0.32 to 0.20 µg I-TEQ/kg) and heavy metals in MSWIFA due to chemical fixation and dilution effect. The S/S mechanism of sodium dimethyldithiocarbamate (SDD) and cement was decreasing heavy metals in the mild acid-soluble fraction to reduce their mobility and bioavailability. Oxidation treatment of leachate reduced the PCDD/F concentration from 49.10 to 28.71 pg/L (i.e., from 1.60 to 0.98 pg I-TEQ/L) by suspension absorption or NaClO oxidation decomposition, whereas a so-called "memory effect" phenomena in the subsequent procedures (adsorption, press filtration, flocculating settling, slurry separation, and carbon filtration) increased it back to 38.60 pg/L (1.66 pg I-TEQ/L). Moreover, the multi-step leachate treatment also effectively reduced the concentrations of heavy metals to 1-4 orders of magnitude lower than the national emission standards. Furthermore, the PCDD/Fs and heavy metals in other multiple media (soil, landfill leachate, groundwater, and river water) and their spatial distribution characteristics site were also investigated. No evidence showed any influence of the landfill on the surrounding liquid media. The slightly higher concentration of PCDD/Fs in the soil samples was ascribed to other waste management processes (transportation and unloading) or other local source (hazardous incineration plant). Therefore, proper management of landfills and leachate has a negligible effect on the surrounding environment.


Assuntos
Poluentes Ambientais , Metais Pesados , Dibenzodioxinas Policloradas , Poluentes Químicos da Água , Cádmio/análise , Carbono , Cinza de Carvão/análise , Dibenzofuranos/análise , Dibenzofuranos Policlorados/análise , Dimetilditiocarbamato/análise , Poluentes Ambientais/análise , Incineração , Metais Pesados/análise , Dibenzodioxinas Policloradas/análise , Sódio/análise , Solo , Resíduos Sólidos/análise , Instalações de Eliminação de Resíduos , Água/análise , Poluentes Químicos da Água/análise
18.
PLoS One ; 17(9): e0269269, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36149869

RESUMO

Despite growing interest in edible seaweeds, there is limited information on seaweed chemical contaminant levels in the Salish Sea. Without this knowledge, health-based consumption advisories can not be determined for consumers that include Tribes and First Nations, Asian and Pacific Islander community members, and recreational harvesters. We measured contaminant concentrations in edible seaweeds (Fucus distichus, F. spiralis, and Nereocystis luetkeana) from 43 locations in the Salish Sea. Metals were analyzed in all samples, and 94 persistent organic pollutants (POPs) (i.e. 40 PCBs, 15 PBDEs, 17 PCDD/Fs, and 22 organochlorine pesticides) and 51 PAHs were analyzed in Fucus spp. We compared concentrations of contaminants to human health-based screening levels calculated from the USEPA and to international limits. We then worked with six focal contaminants that either exceeded screening levels or international limits (Cd, total Hg, Pb, benzo[a]pyrene [BaP], and PCBs) or are of regional interest (total As). USEPA cancer-based screening levels were exceeded in 30 samples for the PCBs and two samples for BaP. Cadmium concentrations did not exceed the USEPA noncancer-based screening level but did exceed international limits at all sites. Lead exceeded international limits at three sites. Because there are no screening levels for total Hg and total As, and to be conservative, we made comparisons to methyl Hg and inorganic As screening levels. All samples were below the methyl Hg and above the inorganic As screening levels. Without knowledge of the As speciation, we cannot assess the health risk associated with the As. While seaweed was the focus, we did not consider contaminant exposure from consuming other foods. Other chemicals, such as contaminants of emerging concern (e.g., PFAS, pharmaceuticals and personal care products), should also be considered. Additionally, although we focused on toxicological aspects, there are cultural and health benefits of seaweed use that may affect consumer choice.


Assuntos
Fluorcarbonetos , Mercúrio , Praguicidas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Alga Marinha , Poluentes Químicos da Água , Benzo(a)pireno , Cádmio , Dibenzofuranos , Monitoramento Ambiental , Éteres Difenil Halogenados , Humanos , Chumbo , Mercúrio/análise , Poluentes Orgânicos Persistentes , Praguicidas/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise
19.
Wei Sheng Yan Jiu ; 51(4): 610-616, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-36047267

RESUMO

OBJECTIVE: To measure polychlorinated biphenyls(PCBs) concentrations in serum of some reproductive aged men in Wuhan and explore the influencing factors of PCBs exposure. METHODS: Based on a cross-sectional study in 2013 on the association between exposure to environmental pollutants and adverse male reproductive health, which was conducted in Wuhan. Levels of dioxins-like PCBs(dl-PCBs) and non-dioxin-like PCBs(ndl-PCBs) in 101 serum samples of men with childbearing age were analyzed via high-resolution gas chromatograph tandem high-resolution mass spectrometer(HRGC-HRMS) method. Multiple linear regression models were used to analyze the associations between PCBs levels and influencing factors. RESULTS: Total concentrations of twelve dl-PCBs(Σdl-PCBs) were in range of 177.85-7271.48 pg/g lipid, the median value was 1530.71 pg/g lipid, and CB-118 was the predominant congener. For six ndl-PCBs, total concentrations(Σndl-PCBs) were in range of 1463.23-40561.47 pg/g lipid, the median value was 5498.37 pg/g lipid, and CB-153 was the predominant congener. The World Health Organization toxicity equivalent(WHO_(2005)-TEQ) of dl-PCBs(ΣTEQ_(dl-PCBs)) were 0.02-162.29 pg TEQ/g lipid, the median value was 1.77 pg TEQ/g lipid. The age was positively correlated with Σmono-ortho PCBs(ß=0.01, 95%CI 0.00-0.02), ΣTEQ_(mono-ortho PCBs)(ß=0.01, 95%CI 0.00-0.02) and Σndl-PCBs(ß=0.02, 95%CI 0.00-0.03). Men who drank alcohol tend to show higher exposure to ΣTEQ_(dl-PCBs)(ß=0.56, 95%CI 0.13-1.00) than those did not drink alcohol. And higher levels of Σndl-PCBs(ß=0.15, 95%CI 0.04-0.26) was found in the men who reside in urban areas as compared to rural one. CONCLUSION: There were PCBs exposure in some reproductive aged men in Wuhan. Age, drink alcohol status, and residence were influencing factors on PCBs.


Assuntos
Benzofuranos , Dioxinas , Poluentes Ambientais , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Adulto , Benzofuranos/análise , Estudos Transversais , Dibenzofuranos Policlorados , Dioxinas/análise , Poluentes Ambientais/análise , Humanos , Lipídeos , Masculino , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise
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