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Polychlorinated naphthalene (PCN) concentrations in the soil at an e-waste recycling area in Guiyu, China, were measured and the associated human cancer risk due to e-waste-related exposures was investigated. We quantified PCNs in the agricultural soil and used these concentrations with predictive equations to calculate theoretical concentrations in outdoor air. We then calculated theoretical concentrations in indoor air using an attenuation factor and in the local diet using previously published models for contaminant uptake in plants and fruits. Potential human cancer risks of PCNs were assessed for multiple exposure pathways, including soil ingestion, inhalation, dermal contact, and dietary ingestion. Our calculations indicated that local residents had a high cancer risk from exposure to PCNs and that the diet was the primary pathway of PCN exposure, followed by dermal contact as the secondary pathway. We next repeated the risk assessment using concentrations for other carcinogenic contaminants reported in the literature at the same site. We found that polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) and PCNs caused the highest potential cancer risks to the residents, followed by polychlorinated biphenyls (PCBs). The relative importance of different exposure pathways depended on the physicochemical properties of specific chemicals.
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Residuos Electrónicos , Neoplasias , Bifenilos Policlorados , Dibenzodioxinas Policloradas , China , Dibenzofuranos , Dibenzofuranos Policlorados/análisis , Detección Precoz del Cáncer , Monitoreo del Ambiente , Humanos , Naftalenos/análisis , Neoplasias/inducido químicamente , Bifenilos Policlorados/análisis , Dibenzodioxinas Policloradas/análisis , Medición de Riesgo , SueloRESUMEN
Polyhalogenated carbazoles (PHCZs) are emerging environmental contaminants that have caused wide concerns due to their dioxin-like toxicity and environmental persistence. It would be desirable to determine all of these chemicals using a simple analytical method. Within this study, a simple and sensitive method combining accelerated solvent extraction (ASE) with gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS) was established to simultaneously analyze eleven frequently detected PHCZs in soil, including CCZ-3, CCZ-36, CCZ-1368, CCZ-2367, BCZ-3, BCZ-27, BCZ-36, BCZ-136, BCZ-1368, 1-B-36-CCZ, 18-B-36-CCZ. The calibration curves of the target analytes showed good linearity (R2â¯>â¯0.99, levelâ¯=â¯6), and method detection limits (MDLs) ranging from 1.5 to 14.6â¯pgâ¯g-1. The average recoveries of the analytes in soil samples ranged from 64% to 126% with the RSD ranging from 2.0% to 10%. The developed method was successfully used for determination of these eleven PHCZs in soil samples from a tie-dye area in southwest China. Total concentrations of these eleven PHCZs ranging up to 46.3â¯ngâ¯g-1â¯dw. CCZ-36, BCZ-3, CCZ-3, 1-B-36-CCZ, 18-B-36-CCZ, and BCZ-1368 were the most abundant compounds in soil.
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Dechlorane 602 (Dec 602), a chlorinated flame retardant, has been widely detected in different environmental matrices and biota. However, toxicity data for Dec 602 seldom have been reported. A metabolomics study based on ultra-high performance liquid chromatography coupled with ion trap time-of-flight mass spectrometry was employed to study the urine and sera metabolic profiles of mice administered with Dec 602 (0, 0.001, 0.1, and 10â¯mg/kg body weight per day) for 7 days. A significant difference in metabolic profiling was observed between the Dec 602 treated group and the control group by multivariate analysis, which directly reflected the metabolic perturbations caused by Dec 602. The metabolomics analyses of urine from Dec 602-exposed animals exhibited an increase in the levels of thymidine and tryptophan as well as a decrease in the levels of tyrosine, 12,13-dihydroxy-9Z-octadecenoic acid, 2-hydroxyhexadecanoic acid and cuminaldehyde. The metabolomics analyses of sera showed a decrease in the levels of kynurenic acid, daidzein, adenosine, xanthurenic acid and hypoxanthine from Dec 602-exposed animals. These findings indicated Dec 602 induced disturbance in phenylalanine, tyrosine and tryptophan biosynthesis, tryptophan metabolism, tyrosine metabolism, pyrimidine metabolism, purine metabolism, ubiquinone and other terpenoid-quinone biosynthesis; phenylalanine metabolism and aminoacyl-tRNA biosynthesis. Significant alterations of immune and neurotransmitter-related metabolites (tyrosine, tryptophan, kynurenic acid, and xanthurenic acid) suggest that the toxic effects of Dec 602 may contribute to its interactions with the immune and neuronal systems. This study demonstrated that the UHPLC-ESI-IT-TOF-MS-based metabolomic approach can obtain more specific insights into the potential toxic effects of Dec 602â¯at molecular level.
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Cromatografía Líquida de Alta Presión , Biomarcadores Ambientales/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Hidrocarburos Clorados/toxicidad , Espectrometría de Masas , Metaboloma/efectos de los fármacos , Compuestos Policíclicos/toxicidad , Animales , Masculino , Redes y Vías Metabólicas/efectos de los fármacos , Metabolómica , Ratones , Análisis MultivarianteRESUMEN
The aryl hydrocarbon receptor (AhR) plays an important role in mediating dioxins toxicity. Currently, genes of P450 families are major research interests in studies on AhR-mediated gene alterations caused by dioxins. Genes related to other metabolic pathways or processes may be also responsive to dioxin exposures. Amino acid transporter B0AT1 (encoded by SLC6A19) plays a decisive role in neutral amino acid transport which is present in kidney, intestine and liver. However, effects of dioxins on its expression are still unknown. In the present study, we focused on the effects of dioxin and dioxin-like compounds on SLC6A19 expression in HepG2 cells. We identified SLC6A19 as a novel putative target gene of AhR activation in HepG2 cells. 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) increased the expression of SLC6A19 in time- and concentration-dependent manners. Using AhR antagonist CH223191 and/or siRNA assays, we demonstrated that certain AhR agonists upregulated SLC6A19 expression via AhR, including TCDD, 1,2,3,7,8-pentachlorodibenzo-p-dioxin (1,2,3,7,8-PeCDD), 2,3,4,7,8- pentachlorodibenzofuran (2,3,4,7,8-PeCDF) and PCB126. In addition, the expression of B0AT1 was also significantly induced by TCDD in HepG2 cells. Our study suggested that dioxins might affect the transcription and translation of SLC6A19 in HepG2 cells, which might be a novel putative gene to assess dioxins' toxicity in amino acid transport and metabolism in liver.
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Sistemas de Transporte de Aminoácidos Neutros/genética , Dioxinas/toxicidad , Contaminantes Ambientales/toxicidad , Receptores de Hidrocarburo de Aril/metabolismo , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Compuestos Azo , Carcinoma Hepatocelular , Dioxinas/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Pirazoles , Transducción de Señal/efectos de los fármacos , Activación Transcripcional/efectos de los fármacosRESUMEN
A simple, rapid and accurate analytical method was developed for the analysis of eight tea catechins and four theaflavins simultaneously in three types of tea (green, black and oolong tea), using ultra high performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (HPLC-MS-MS) in multiple-reaction monitoring (MRM) mode. This method using HPLC-MS-MS in positive mode was performed on a CAPCELL PAK C18 MGIII (2.0mm×100mm, 3µm) column (Shiseido) with the mobile phase consisting of 0.1% aqueous formic acid (A) and methanol (B) in gradient elution at a flow rate of 0.3mLmin-1, and the column temperature set at 30°C. The optimized HPLC-MS-MS methodology is selective and specific, and was validated for eight catechins and four theaflavins widely reported in different teas. Satisfactory linearity was achieved in linear range (0.02-5µgmL-1 for catechins and 0.02-20µgmL-1 for theaflavins) and fine determination coefficient (r2>0.9935). The recoveries ranged from 65% to 115% with the RSD ranging from 2.4% to 6.7%. The methodology was used to evaluate the target polyphenols concentration in three types of tea samples.
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Biflavonoides/análisis , Catequina/análisis , Espectrometría de Masas en Tándem/métodos , Té/química , Catequina/análogos & derivados , Cromatografía Líquida de Alta Presión/métodos , Polifenoles/análisis , Espectrometría de Masa por Ionización de Electrospray/métodosRESUMEN
Samples of Pleurotus ostreatus were exposed to fungicide carbendazim to study the effect of processing on the residues. In most cases, processing operations led to a significant decrease in residue levels in the finished products, particularly through washing, drying, and cooking processes. The results indicated that rinsing under running tap water led to more than 70.30% loss in carbendazim residues. When dried under sunlight could remove more than 70.30% residues. There was a 63.90-97.14% reduction after steaming, with processing time extending, the removal rates increased especially for lower initial residue level samples. The residue was almost completely removed by frying combined with microwave heating. Furthermore, boiling the mushrooms reduced the residue in the mushroom and no carbendazim residues were determined in the broth.
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BACKGROUND: Although the chlorinated flame retardant Dechlorane (Dec) 602 has been detected in food, human blood, and breast milk, there is limited information on potential health effects, including possible immunotoxicity. OBJECTIVES: We determined the immunotoxic potential of Dec 602 in mice by examining the expression of phenotypic markers on thymocyte and splenic lymphocyte subsets, Th1/Th2 transcription factors, and the production of cytokines and antibodies. METHODS: Adult male C57BL/6 mice were orally exposed to environmentally relevant doses of Dec 602 (1 and 10 µg/kg body weight per day) for 7 consecutive days. Thymocyte and splenic CD4 and CD8 subsets and splenocyte apoptosis were examined by flow cytometric analysis. Cytokine expression was measured at both the mRNA and the protein levels. Levels of the transcription factors Th1 (T-bet and STAT1) and Th2 (GATA3) were determined using quantitative real-time polymerase chain reaction (qPCR). Serum levels of immunoglobulins IgG1, IgG2a, IgG2b and IgE were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Splenic CD4+ and CD8+ T cell subsets were decreased compared with vehicle controls, and apoptosis was significantly increased in splenic CD4+ T cells. Expression (mRNA and protein) of Th2 cytokines [interleukin (IL)-4, IL-10, and IL-13] increased, and that of Th1 cytokines [IL-2, interferon (IFN)-γ and tumor necrosis factor (TNF)-α] decreased. The Th2 transcriptional factor GATA3 increased, whereas the Th1 transcriptional factors T-bet and STAT1 decreased. As additional indicators of the Th2-Th1 imbalance, production of IgG1 was significantly increased, whereas IgG2a was reduced. CONCLUSIONS: To our knowledge, we are the first to report evidence of the effects of Dec 602 on immune function in mice, with findings indicating that Dec 602 exposure favored Th2 responses and reduced Th1 function. CITATION: Feng Y, Tian J, Xie HQ, She J, Xu SL, Xu T, Tian W, Fu H, Li S, Tao W, Wang L, Chen Y, Zhang S, Zhang W, Guo TL, Zhao B. 2016. Effects of acute low-dose exposure to the chlorinated flame retardant dechlorane 602 and Th1 and Th2 immune responses in adult male mice. Environ Health Perspect 124:1406-1413; http://dx.doi.org/10.1289/ehp.1510314.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Contaminantes Ambientales/toxicidad , Retardadores de Llama/toxicidad , Hidrocarburos Clorados/toxicidad , Sistema Inmunológico/efectos de los fármacos , Compuestos Policíclicos/toxicidad , Linfocitos T/efectos de los fármacos , Balance Th1 - Th2/efectos de los fármacos , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Ratones Endogámicos C57BL , Linfocitos T/inmunologíaRESUMEN
With the advance in material science and the need to diversify market applications, silver nanoparticles (AgNPs) are modified by different surface coatings. However, how these surface modifications influence the effects of AgNPs on human health is still largely unknown. We have evaluated the uptake, toxicity and pharmacokinetics of AgNPs coated with citrate, polyethylene glycol, polyvinyl pyrolidone and branched polyethyleneimine (Citrate AgNPs, PEG AgNPs, PVP AgNPs and BPEI AgNPs, respectively). Our results demonstrated that the toxicity of AgNPs depends on the intracellular localization that was highly dependent on the surface charge. BPEI AgNPs (ζ potential = +46.5 mV) induced the highest cytotoxicity and DNA fragmentation in Hepa1c1c7. In addition, it showed the highest damage to the nucleus of liver cells in the exposed mice, which is associated with a high accumulation in liver tissues. The PEG AgNPs (ζ potential = -16.2 mV) showed the cytotoxicity, a long blood circulation, as well as bioaccumulation in spleen (34.33 µg/g), which suggest better biocompatibility compared to the other chemically modified AgNPs. Moreover, the adsorption ability with bovine serum albumin revealed that the PEG surface of AgNPs has an optimal biological inertia and can effectively resist opsonization or non-specific binding to protein in mice. The overall results indicated that the biodistribution of AgNPs was significantly dependent on surface chemistry: BPEI AgNPs > Citrate AgNPs = PVP AgNPs > PEG AgNPs. This toxicological data could be useful in supporting the development of safe AgNPs for consumer products and drug delivery applications.
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Administración Intravenosa , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Plata/farmacocinética , Plata/toxicidad , Adsorción , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Química Farmacéutica , Ácido Cítrico/química , Fragmentación del ADN/efectos de los fármacos , Masculino , Nanopartículas del Metal/administración & dosificación , Ratones , Tamaño de la Partícula , Polietilenglicoles/química , Polietileneimina/química , Povidona/análogos & derivados , Povidona/química , Albúmina Sérica Bovina/química , Plata/administración & dosificación , Plata/sangre , Propiedades de Superficie , Distribución TisularRESUMEN
Dechlorane 602 (Dec 602), Dechlorane 603 (Dec 603), Dechlorane 604 (Dec 604), Dechlorane 604 component B (Dec 604 CB) and Dechlorane Plus (DP) were analyzed in soil and fish collected across e-waste recycling sites in Guiyu. The results indicate that soil and fish are contaminated with dechlorane compounds especially Dec 602 and DP which show high concentrations in the samples near recycling sites. Dec 604 and Dec 604 CB are not detected. The photo-degradation experiment indicates that Dec 604 and Dec 604 CB have much faster degradation rates compared to other dechloranes, suggesting they might be more vulnerable to degradation during recycling processes and further studies are needed for assessing the environmental fate and persistence of their degradation products. Dec 602 has not been manufactured in China, the detection of Dec 602 in soil and fish implies that it might be from imports of recyclable materials from developed countries.
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Residuos Electrónicos/análisis , Monitoreo del Ambiente/métodos , Peces , Retardadores de Llama/análisis , Reciclaje , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis , Animales , China , Peces/metabolismo , Hidrocarburos Clorados/análisis , Músculos/química , Compuestos Policíclicos/análisis , Ríos/químicaRESUMEN
Recently, acetylcholinesterase (AChE, EC 3.1.1.7) has received increased attention in the field of environmental sciences. Evaluation of the effects of environmental contaminants on AChE enzymatic activity not only can reflect, to some extent, the interference with the nervous system, but also can be used for monitoring pollution. Our previous study showed that 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) suppressed neuronal AChE enzymatic activity via transcriptional downregulations mediated by aryl hydrocarbon receptor. In the present study, the effects of several other dioxin-like compounds (DLCs) on neuronal AChE activity were determined, including 1,2,3,7,8-pentachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, 2,3,4,7,8-pentachlorodibenzofuran, and 2,3,7,8-tetrabromodibenzo-p-dioxin. The results showed that the enzymatic activity of AChE was significantly decreased by approximately 15-30 % after exposure to a certain concentrations of the DLCs, whereas incubating neuronal cell lysates directly with these DLCs did not inhibit AChE enzyme. Subsequent molecular mechanism study showed that these chemicals could decrease ACHE promoter activity, as well as AChE T mRNA expression, thereby suggesting the involvements of transcriptional regulation in these effects. These findings on DLCs are similar with those on 2,3,7,8-TCDD, pointing to the possibility that exposure to dioxin and DLCs, which frequently coexist in the contaminated environments, may concurrently interfere with the cholinergic functions via AChE.
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Acetilcolinesterasa/metabolismo , Regulación hacia Abajo , Dibenzodioxinas Policloradas/farmacología , Transcripción Genética , Acetilcolinesterasa/genética , Línea Celular Tumoral , Humanos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Dibenzodioxinas Policloradas/análogos & derivados , Regiones Promotoras Genéticas , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
OBJECTIVE: To conduct comparative study on the volatile components from Polygonati Rhizoma during processing. METHOD: Volatile oil was obtained from Polygonati Rhizoma by steam distillation (SD). Volatile components were concentrated by a purge and trap-thermal desorption (P&T-TD) method, and analyzed with gas chromatography-mass spectrometry (GC-MS), which were comparative by analyzed with the method of SD-GC-MS simultaneously. RESULT: The change in quantity and quality of volatile components in pre and post processed Polygonati Rhizoma were observed. Fifty-one compounds were checked out with SD-GC-MS, while 11 compounds with P&T-TD-GC-MS. CONCLUSION: This study is useful to illustrate the mechanism of decreasing toxicity and stimulating components after being processed.