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1.
Arch Environ Contam Toxicol ; 70(3): 452-63, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26577448

RESUMO

The purpose of this study was to assess the levels of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDE), and four heavy metals (arsenic, cadmium, and lead) in outdoor surface soils (50 samples) collected from the metropolitan area of Monterrey in Mexico. Total PBDEs levels ranged from 1.80 to 127 µg/kg, with mean total PBDEs level of 14.2 ± 21.5 µg/kg (geometric mean ± standard deviation). For PCBs, the mean total level in the studied soils was 23.5 ± 20.2 µg/kg (range 4.0-65.5 µg/kg). An important finding in our study was that all soil samples (100%) had detectable levels of the metabolite p,p'-DDE. Moreover, the mean total DDT level (∑p'p-DDT and p'p-DDE) was approximately 132 ± 175 µg/kg. The mean levels for arsenic, cadmium, and lead in soil were 5.30 ± 1.35 (range 1.55-7.85) mg/kg, 2.20 ± 1.20 (range 0.65-6.40) mg/kg, and 455 ± 204 (range 224-1230) mg/kg, respectively. Our study has several limitations, the most notable of which is the small sample of soils evaluated. However, this screening study provided concentration data for the occurrence of POPs and four heavy metals in soil from the metropolitan area of Monterrey, Nuevo Leon, Mexico, and taking into consideration that soil is an important pathway of exposure for people, a biomonitoring program for the surveillance of the general population in the metropolitan area of Monterrey, Nuevo Leon is deemed necessary.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , Arsênio , Cádmio , DDT , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano , Éteres Difenil Halogenados/análise , Hidrocarbonetos Clorados/análise , México , Bifenilos Policlorados/análise , Solo
2.
J Appl Toxicol ; 35(10): 1189-99, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26281020

RESUMO

The antimicrobial properties of silver nanoparticles (AgNPs) have made these particles one of the most used nanomaterials in consumer products. Therefore, an understanding of the interactions (unwanted toxicity) between nanoparticles and human cells is of significant interest. The aim of this study was to assess the in vitro cytotoxicity effects of silver nanoclusters (AgNC, < 2 nm diameter) on peripheral blood mononuclear cells (PBMC). Using flow cytometry and comet assay methods, we demonstrate that exposure of PBMC to AgNC induced intracellular reactive oxygen species (ROS) generation, DNA damage and apoptosis at 3, 6 and 12 h, with a dose-dependent response (0.1, 1, 3, 5 and 30 µg ml(-1)). Advanced electron microscopy imaging of complete and ultrathin-sections of PBMC confirmed the cytotoxic effects and cell damage caused by AgNC. The present study showed that AgNC produced without coating agents induced significant cytotoxic effects on PBMC owing to their high aspect ratio and active surface area, even at much lower concentrations (<1 µg ml(-1)) than those applied in previous studies, resembling what would occur under real exposure conditions to nanosilver-functionalized consumer products.


Assuntos
Leucócitos Mononucleares/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Adulto , Apoptose/efeitos dos fármacos , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Ensaio Cometa , Dano ao DNA , Feminino , Citometria de Fluxo , Humanos , Técnicas In Vitro , Inflamação/induzido quimicamente , Inflamação/patologia , Masculino , Microscopia Eletrônica , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície , Adulto Jovem
3.
Environ Monit Assess ; 187(1): 4119, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25480599

RESUMO

The aim of this study was to assess the levels of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyltrichloroethane (DDT), p,p'-dichlorodiphenyldichloroethylene (DDE), and four heavy metals (arsenic, cadmium, lead, and mercury) in soil from the city of San Luis Potosí in Mexico. In order to confirm the presence of the previously mentioned compounds, outdoor surface soil samples were collected and analyzed by gas chromatography/mass spectrometer for PBDEs, PCBs, DDT, and DDE. Meanwhile, heavy metals were quantified using the atomic absorption spectrophotometry technique. The total PBDEs levels ranged from 5.0 to 134 µg/kg dry weight (dw), with a total mean PBDEs level of 22.0 ± 32.5 µg/kg dw (geometric mean ± standard deviation). For PCBs, the total mean level in the studied soil was 21.6 ± 24.7 µg/kg dw (range,

Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Cidades , DDT/análise , Diclorodifenil Dicloroetileno/análise , Éteres Difenil Halogenados/análise , Hidrocarbonetos Clorados/análise , México , Bifenilos Policlorados/análise
4.
J Environ Sci Health B ; 49(2): 87-93, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24328540

RESUMO

The aim of this study was to assess the levels of dichlorodiphenyltrichloroethane (DDT) and dichlorodiphenyldichloroethylene (DDE) in the blood of children living in the southeastern region of Mexico. In this study, we found high levels of DDT and its principal metabolite (DDE) in the blood of children residing in the communities studied. The levels of total DDT found in our study ranged from 4,676.4 ng/g lipid to 64,245.2 ng/g lipid. All of the children in the study had detectable levels of DDT and/or DDE. In conclusion, our data indicate that children living within the study areas are exposed to high levels of DDT and DDE. Moreover, these results can be used as a trigger to revisit local policies on environmental exposures.


Assuntos
DDT/sangue , Diclorodifenil Dicloroetileno/sangue , Exposição Ambiental , Poluentes Ambientais/sangue , Inseticidas/sangue , Criança , Monitoramento Ambiental , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , México
5.
Immunopharmacol Immunotoxicol ; 34(4): 627-32, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22233178

RESUMO

The objective of this study was evaluate the effect of coplanar polychlorinated biphenyls (PCB) 118-congener (PCB like-dioxin) and noncoplanar PCB 153-congener (PCB no like-dioxin) on differentiation of humans T-CD4+ lymphocytes into Th1 or Th2 subpopulations. Peripheral blood mononuclear cells (PBMC) were isolated from healthy volunteers (aged 25-30 years); T-CD4+ lymphocytes were separated from PBMC. Then, the differentiation of T-CD4+ cells into Th1 or Th2 subpopulation was performed and the intracellular cytokines analyses were assessed. No effect on IFNγ (produced by Th1 cells) production was observed when the cells were treated with both PCBs congeners. However, the PCB 118-congener induced an increase of IL-4-producing T-CD4 cells (produced by Th2 cells), PCB153 not exerted any effect on IL-4 production. The clinical significance of our data is uncertain, therefore, more studies are necessary in order to elucidate the effects generated in exposed human individual.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Interleucina-4/imunologia , Bifenilos Policlorados/farmacologia , Células Th1/imunologia , Células Th2/imunologia , Adulto , Diferenciação Celular/imunologia , Feminino , Humanos , Masculino
6.
Bull Environ Contam Toxicol ; 88(6): 828-32, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22415648

RESUMO

The aim of this study was to evaluate the exposure levels to persistent organic pollutants and 1-hydroxypyrene in children living in an endemic malaria zone in Mexico. The blood levels for 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and lindane ranged from 15.4 to 17,886.5 ng/g lipid, 6,624.3 to 100,119.0 ng/g lipid, and 351.1 to 6,153.8 ng/g lipid, respectively. For total polychlorinated biphenyls the blood levels ranged from 2,584.9 to 14,547.9 ng/g lipid. Regarding urinary 1-hydroxypyrene levels, the mean level was 2.9 ± 3.1 µmol/mol creatinine. In conclusion, the children in our study are exposed to levels higher than normal to mixtures of environmental contaminants.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Malária/epidemiologia , Pirenos/metabolismo , Adolescente , Criança , DDT/sangue , DDT/metabolismo , DDT/urina , Diclorodifenil Dicloroetileno/sangue , Diclorodifenil Dicloroetileno/metabolismo , Diclorodifenil Dicloroetileno/urina , Exposição Ambiental/análise , Poluentes Ambientais/sangue , Poluentes Ambientais/urina , Feminino , Hexaclorocicloexano/sangue , Hexaclorocicloexano/metabolismo , Hexaclorocicloexano/urina , Humanos , Masculino , México , Bifenilos Policlorados/sangue , Bifenilos Policlorados/metabolismo , Bifenilos Policlorados/urina
7.
Bull Environ Contam Toxicol ; 88(6): 833-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22487962

RESUMO

The aim of this study was to evaluate hexachlorocyclohexane (HCH) exposure in children living in nine hot spots in four Mexican states. We analyzed HCH (α, ß, and γ-isomers) in blood using gas chromatography/mass spectrometry. HCH exposure level in 261 children was assessed and approximately 75 % of the children studied had detectable levels of HCH. These levels ranged from 188 to 40,096.7 ng/g lipid. The highest mean levels were found in Lacanja (5,446.9 ng/g lipid), an indigenous community in Chiapas, Mexico. Our data indicate high exposure to HCH in children living in these communities.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Hexaclorocicloexano/sangue , Praguicidas/sangue , Criança , Pré-Escolar , Exposição Ambiental/análise , Feminino , Humanos , Masculino , México
8.
Bull Environ Contam Toxicol ; 89(4): 925-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22847182

RESUMO

The purpose of this study was to measure levels of polybrominated diphenyl ethers (PBDEs) in the blood of children (50 individuals) living in Guadalajara, Jalisco, Mexico. We analyzed six PBDE congeners by gas chromatography-mass spectrometry. Total PBDE levels ranged from not detectable (nd) to 15.2 µg/L on a whole-weight basis and from nd to 6,435 ng/g lipid on a lipid-weight basis. The dominant congener in our study was BDE-153, followed by BDE-154, BDE-99, BDE-100, and BDE-47. Levels of BDE-209 were below the detection limit. Our data indicate that children living in the areas studied in this work are exposed to high levels of PBDEs.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/sangue , Criança , Exposição Ambiental/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , México , Bifenil Polibromatos/sangue
9.
Toxics ; 11(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36668754

RESUMO

The exposure to air pollutants causes significant damage to health, and inefficient cooking and heating practices produce high levels of household air pollution, including a wide range of health-damaging pollutants such as fine particles, carbon monoxide and PAHs. The exposure to PAHs has been associated with the development of neoplastic processes, asthma, genotoxicity, altered neurodevelopment and inflammation. The effects on the induction of proinflammatory cytokines are attributed to the activation of AhR. However, the molecular mechanisms by which the PAHs produce proinflammatory effects are unknown. This study was performed on a group of 41 Mexican women from two rural communities who had stoves inside their houses, used wood as biomass fuel, and, thus, were vulnerable. According to the urinary 1-OHP concentration, the samples were stratified into two groups for determination of the levels of TNF-α, AhR, CYP1B1, miR-125b and miR-155 expression. Our results showed that the CYP1B1, TNF-α, miR-125b and miR-155 expression levels were not statistically different between women with the lowest and highest levels of 1-OHP. Interestingly, high levels of PAHs promoted augmented expression of AhR, which is a protein involved in the modulation of inflammatory pathways in vivo, suggesting that cell signaling of AhR may be implicated in several pathogenesis processes.

10.
Environ Toxicol Pharmacol ; 83: 103598, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33516900

RESUMO

The environmental contamination with lead (Pb) is considered a critical issue worldwide. Therefore, this study aimed to evaluate the expression levels of circulating miRNAs (miR-155, miR-126, and miR-145) in Mexican women exposed to Pb. Blood lead levels (BLL) were assessed in enrolled women (n = 190) using an atomic absorption method. Also, serum miRNAs expression levels were quantified through a real-time PCR assay. A mean BLL of 10.5 ± 4.50 µg/dL was detected. Overexpression of miR-155 was detected in highly exposed women. Besides, a significant simple positive relationship (p < 0.05) was found between BLL and serum miR-155 expression levels. Additionally, a significant inverse correlation (p < 0.05) was determined between BLL and serum miR-126 expression levels, as downregulation of miR-126 expression levels was observed in highly exposed women. The findings in this study are the concern, as epigenetic changes detected may represent a connection between health illnesses and Pb exposure.


Assuntos
Poluentes Ambientais/sangue , Chumbo/sangue , MicroRNAs/sangue , Adulto , Exposição Ambiental/análise , Epigênese Genética , Feminino , Humanos , México , Pessoa de Meia-Idade
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