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1.
Environ Sci Pollut Res Int ; 27(12): 14207-14215, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32043247

RESUMO

This study was performed to determine the effects of in vitro human digestion on the concentrations of five insecticides, namely 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE), bifenthrin, and fipronil. In vitro models included all the steps of human digestion, i.e., passage through the mouth, stomach, small intestine, and large intestine (with enteric bacteria). The concentrations of DDT and fipronil did not change (P > 0.05) until small intestinal digestion, whereas those of DDD, DDE, and bifenthrin decreased (P < 0.05) at each digestion step. The concentrations of all the insecticides decreased (P < 0.05) during the large intestinal digestion step with enteric bacteria, Lactobacillus sakei and Escherichia coli. In conclusion, the concentrations of all the tested insecticides decreased during all the steps of in vitro human digestion and were especially reduced by enteric bacteria during the large intestinal digestion step.


Assuntos
Inseticidas/análise , DDT/análise , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano/análise , Humanos
2.
Environ Monit Assess ; 191(11): 665, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650258

RESUMO

The Pine River downstream of the Velsicol Superfund site has been contaminated with various hydrophobic organic pollutants for more than 50 years. Remediation and sediment dredging near the site began in spring of 1999, and was completed in 2006. In 2011, the Michigan Department of Environmental Quality completed a baseline assessment report long-term monitoring plan for the Pine River. However, there has been limited assessment of the benthic community since this evaluation. The objective of this research was to evaluate the risk of Pine River sediment to aquatic macroinvertebrates downstream from the Superfund site after decades of degradation and dredging using the Triad approach. Three sites were selected downstream from the Superfund site, and an upstream reference site was used. At each site, macroinvertebrates surveys were conducted and sediments were collected for chemical analysis of DDT (1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane) and its degradation products and for laboratory toxicity testing for mortality and sublethal effects using Hyalella azteca and Chironomus dilutus. Sediment concentrations of DDT, DDD, and DDE were below levels expected to cause toxicity, and there was no observed toxicity in laboratory tests. Additionally, there were no statistically significant differences in richness, richness of Ephemeroptera, Plecoptera, and Trichoptera (EPT) species, total EPT abundance, percent EPT, or percent dominant taxa between the reference site and the downstream sites. There was an observed decrease in abundance of macroinvertebrate taxa at all downstream sites and a shift in macroinvertebrate structure when comparing the reference with most impaired sites. Although the sites downstream of the Superfund site remain different than the upstream control, there are improvements in species composition and abundance. However, more research is needed to evaluate the potential effects on ecosystem function.


Assuntos
DDT/análise , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Locais de Resíduos Perigosos , Poluentes Químicos da Água/análise , Anfípodes/efeitos dos fármacos , Animais , Chironomidae/efeitos dos fármacos , DDT/metabolismo , Ecossistema , Michigan , Rios/química , Testes de Toxicidade
3.
Methods Mol Biol ; 2013: 3-27, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31267490

RESUMO

Malaria has infected and killed humans since long before history began recording evidence of the parasite's pernicious influence. The extraordinary discoveries of the Plasmodium parasite by Charles Louis Alphonse Laveran in 1880, and the role of the Anopheles mosquito in transmission of the parasite to humans by Sir Ronald Ross in 1897, led to an understanding of the parasite life cycle and ultimately to the development of interventions that would interrupt disease transmission. Almost as soon as the insecticidal properties of dichlorodiphenyltrichloroethane (DDT) were discovered in 1939, the public health profession began battling to achieve a world free of malaria. That vision persists as the aim of all malariologists and, increasingly, the goal of all nations that remain endemic for malaria. This chapter recounts the history of malaria eradication and elimination efforts throughout the world and focuses on the current status of country-led and country-driven malaria elimination programs, along with the technical strategies recommended by the World Health Organization (WHO) for achievement of malaria elimination.


Assuntos
Malária/transmissão , Organização Mundial da Saúde/organização & administração , Animais , Diclorodifenildicloroetano/uso terapêutico , Humanos
5.
Regul Toxicol Pharmacol ; 103: 301-313, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30794837

RESUMO

Deriving human health risk estimates for environmental chemicals has traditionally relied on in vivo toxicity databases to characterize potential adverse health effects and associated dose-response relationships. In the absence of in vivo toxicity information, new approach methods (NAMs) such as read-across have the potential to fill the required data gaps. This case study applied an expert-driven read-across approach to identify and evaluate analogues to fill non-cancer oral toxicity data gaps for p,p'-dichlorodiphenyldichloroethane (p,p'-DDD), an organochlorine contaminant known to occur at contaminated sites in the U.S. The source analogue p,p'-dichlorodiphenyltrichloroethane (DDT) and its no-observed-adverse-effect level of 0.05 mg/kg-day were proposed for the derivation of screening-level health reference values for the target chemical, p,p'-DDD. Among the primary similarity contexts (structure, toxicokinetics, and toxicodynamics), toxicokinetic considerations were instrumental in separating p,p'-DDT as the best source analogue from other potential candidates (p,p'-DDE and methoxychlor). In vitro high-throughput screening (HTS) assays from ToxCast were used to evaluate similarity in bioactivity profiles and make inferences toward plausible mechanisms of toxicity to build confidence in the read-across approach. This work demonstrated the value of NAMs such as read-across and in vitro HTS in human health risk assessment of environmental contaminants with the potential to inform regulatory decision-making.


Assuntos
Diclorodifenildicloroetano/efeitos adversos , Poluentes Ambientais/efeitos adversos , Inseticidas/efeitos adversos , Monitoramento Ambiental , Ensaios de Triagem em Larga Escala , Humanos , Medição de Risco
6.
Environ Sci Pollut Res Int ; 26(9): 8779-8788, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30712212

RESUMO

DDT transformation to DDD in soil is the most commonly reported pathway under anaerobic conditions. A few instances of DDT conversion to products other than DDD/DDE have been reported under aerobic conditions and hardly any under anaerobic conditions. In particular, few reports exist on the anaerobic degradation of DDT in African tropical soils, despite DDT contamination arising from obsolete pesticide stockpiles in the continent as well as new contamination from DDT use for mosquito and tsetse fly control. Moreover, the development of possible remediation strategies for contaminated sites demands adequate understanding of different soil processes and their effect on DDT persistence, hence necessitating the study. The aim of this work was to study the effect of simulated anaerobic conditions and slow-release carbon sources (compost) on the dissipation of DDT in two tropical clay soils (paddy soil and field soil) amenable to periodic flooding. The results showed faster DDT dissipation in the field soil but higher metabolite formation in the paddy soil. To explain this paradox, the levels of dissolved organic carbon and carbon mineralization (CH4 and CO2) were correlated with p,p-DDT and p,p-DDD concentrations. It was concluded that DDT underwent reductive degradation (DDD pathway) in the paddy soil and both reductive (DDD pathway) and oxidative degradation (non-DDD pathway) in the field soil.


Assuntos
DDT/química , Diclorodifenildicloroetano/química , Praguicidas/química , Poluentes do Solo/química , Solo/química , Carbono , Argila , Compostagem , DDT/análise , Recuperação e Remediação Ambiental , Clima Tropical
7.
Environ Sci Technol ; 53(3): 1305-1314, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30608655

RESUMO

Nonextractable residues (NER) are pollutants incorporated into the matrix of natural solid matter via different binding mechanisms. They can become bioavailable or remobilize during physical-chemical changes of the surrounding conditions and should thus not be neglected in environmental risk assessment. Sediments, soils, and groundwater sludge contaminated with DDXs (DDT, dichlorodiphenyltrichloroethane; and its metabolites) were treated with solvent extraction, sequential chemical degradation, and thermochemolysis to study the fate of NER-DDX along different environmental aquatic-terrestrial pathways. The results showed that DDT and its first degradation products, DDD (dichlorodiphenyldichloroethane) and DDE (dichlorodiphenyldichloroethylene), were dominant in the free extractable fraction, whereas DDM (dichlorodiphenylmethane), DBP (dichlorobenzophenone), and DDA (dichlorodiphenylacetic acid) were observed primarily after chemical degradation. The detection of DDA, DDMUBr (bis( p-chlorophenyl)-bromoethylene), DDPU (bis( p-chlorophenyl)-propene) and DDPS (bis( p-chlorophenyl)-propane) after chemical treatments evidenced the covalent bindings between these DDXs and the organic matrix. The identified NER-DDXs were categorized into three groups according to the three-step degradation process of DDT. Their distribution along the different pathways demonstrated significant specificity. Based on the obtained results, a conceptual model of the fate of NER-DDXs on their different environmental aquatic-terrestrial pathways is proposed. This model provides basic knowledge for risk assessment and remediation of both extractable and nonextractable DDT-related contaminations.


Assuntos
DDT , Sedimentos Geológicos , Diclorodifenil Dicloroetileno , Diclorodifenildicloroetano , Monitoramento Ambiental
8.
Bull Environ Contam Toxicol ; 102(1): 13-18, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30443660

RESUMO

We report the levels of mercury (Hg) and nine organochlorine pesticides [OCPs: α-hexachlorocyclohexane (HCH), ß-HCH, γ-HCH, δ-HCH, α-Endosulfan, ß-Endosulfan, Endosulfan sulfate, p,p'-dichlorodiphenyldichloroethylene (DDE) and p,p'-dichlorodiphenyldichloroethane (DDD)] in the terrestrial environment (moss and soil) and water (OCPs only) of Schirmacher Hills, Antarctica. This area has never been studied for mercury and not for OCPs since 1988. Mercury levels in moss, 66 ± 37 ng/g dry weight (dw), are comparable to other Antarctic locations. Levels of α-HCH, below detection to 4.48 ng/g dw, and p,p'-DDE, below detection to 31 ng/g dw, in mosses are lower or marginally higher than other Antarctic locations. No other OCPs were detected in moss. None of the OCPs were detected in soil. This suggests that Schirmacher Hills may be considered as a background site with respect to mercury and analyzed OCPs, despite the operation of two old research stations (Maitri, est. 1989, and Novolazarevskaya, est. 1961) in the region.


Assuntos
Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Mercúrio/análise , Regiões Antárticas , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano/análise , Endossulfano/análogos & derivados , Endossulfano/análise , Monitoramento Ambiental , Hexaclorocicloexano/análise , Praguicidas/análise , Solo/química
9.
Clin Endocrinol (Oxf) ; 89(6): 805-812, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30222204

RESUMO

OBJECTIVE: Mitotane/Op'DDD is used in the treatment of adrenocortical carcinoma and for other causes of hypercortisolism. Mitotane inhibits cortisol secretion and displays adrenolytic and antitumor actions. This compound is a metabolite of the pesticide and endocrine disruptor DDT (dichlorodiphenyltrichloroethane) and is classified among teratogenic compounds worldwide. However, little is known about its effects on human development. DESIGN: The outcome of four children exposed to mitotane during their intrauterine life was examined. PATIENTS: Patients having conceived while taking mitotane, or with detectable mitotane plasma levels, were retrospectively recruited via the French COMETE and FIRENDO networks. MEASUREMENTS: Mitotane in maternal plasma, adrenocortical hormones in children. RESULTS: Three women treated with mitotane gave birth to four children. During early pregnancy, all patients had detectable mitotane plasma levels (0.9, 2.4 and 6.7 mg/L, respectively). During pregnancy, no foetal malformations were detected. The four exposed newborns presented at birth with apparently normal adrenal function and genitalia. One twin female had a low birthweight. Evaluation at birth and after 3 months, 2 years and 7 years of follow-up showed no significant neurological abnormality. Evaluation of adrenocortical functions showed no cortisol deficiency. CONCLUSIONS: Unexpectedly, exposure of these four children to mitotane during foetal life seemed to have no clear teratogenic effect. However, considering the sub-therapeutic mitotane concentrations used here, the small number of cases, and because long-term follow-up is unknown, we strongly advise not to take mitotane during pregnancy and still recommend avoiding pregnancy, at least as long as mitotane plasma levels remain detectable.


Assuntos
Diclorodifenildicloroetano/toxicidade , Feto/efeitos dos fármacos , Mitotano/toxicidade , Adulto , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Estudos Retrospectivos , Adulto Jovem
10.
Environ Pollut ; 243(Pt A): 437-443, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30212798

RESUMO

The objective of this study was to determine the effects of cooking and in vitro human digestion on the changes of five insecticides-fipronil, bifenthrin, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), and 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE)-in egg whites and yolks. Each insecticide was applied to egg whites and yolks at a concentration of 1000 µg/g. After cooking the egg whites and yolks, concentrations of bifenthrin, DDD, and DDE decreased (P < 0.05), whereas those of fipronil and DDT were unchanged (P > 0.05) in both egg whites and yolks. Next, an in vitro human digestion model that simulates all the steps of human digestion was employed. Until digestion in the small intestine, the concentrations of fipronil and DDT in the cooked egg whites and yolks were unchanged (P > 0.05), whereas those of bifenthrin, DDD, and DDE decreased (P < 0.05) at each digestion step. In the large intestinal digestion step with Escherichia coli and Lactobacillus sakei as enterobacteria, the concentrations of all the insecticides decreased (P < 0.05) in the cooked egg whites and yolks. Among the insecticides, bifenthrin showed the lowest concentration (P < 0.05). In conclusion, the use of bifenthrin as an insecticide would be comparatively less toxic than other insecticides in terms of environmental pollution and human health, because of its easy degradation.


Assuntos
DDT/análise , Diclorodifenil Dicloroetileno/análise , Digestão , Clara de Ovo/química , Gema de Ovo/química , Inseticidas/análise , Culinária , Diclorodifenildicloroetano/análise , Poluição Ambiental , Humanos , Técnicas In Vitro , Modelos Biológicos , Pirazóis/análise , Piretrinas/análise
11.
Chirality ; 30(9): 1088-1095, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29978905

RESUMO

The environmental stereoselective uptake and degradation of (±)-o,p-DDD pesticide stereomers in water-sediment system are described. The results were analyzed by artificial neural network model. The optimized experimental parameters were concentration of o,p-DDD streamers (7.0 µg L-1 ), experimental time (60 min), pH (6), dose (5.0 g L-1 ), and temperature (25°C). The maximum uptake and degradation were 87% and 85% and 33.0% and 30.5% for (-)- and (+)-stereomers of o,p-DDD in 15-day time. Both uptake and degraded phenomenon showed first-order rate reaction. Thermodynamic variables indicated exothermic nature of uptake and degradation processes. The uptake and degradation were slightly higher for (-)-stereomer than (+)-stereomer of o,p-DDD. It was assumed that both uptake and degradation processes are accountable for the removal of the streomers of o,p-DDD from earth's ecosystem, but the uptake is responsible for major contribution. The magnitudes of relative errors obtained by artificial neural network model were in the range of ±0.2 to 3.5, indicating good applicability of the experimental data. The results are very useful to control the environmental contamination due to the chiral o,p-DDD pesticide as its two enantiomers have different ecological toxicities.


Assuntos
Diclorodifenildicloroetano/química , Sedimentos Geológicos/química , Praguicidas/química , Poluentes Químicos da Água/química , Cinética , Redes Neurais de Computação , Estereoisomerismo , Termodinâmica
12.
Chemosphere ; 201: 1-5, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29505918

RESUMO

Dichlorodiphenyltrichloroethane (DDT) is an insecticidal organochlorine pesticide with; known potential for neurotoxic effects in wildlife. The United States Environmental Protection Agency (US EPA) registration for this pesticide has been cancelled and there are currently no federally active products that contain this ingredient in the U.S. We present a case of a colony of big brown bats (E. Fuscus) found dead in the attic roost of an administrative building; in the city of Hamilton, Montana from unknown cause. DDT and its metabolites; dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) were detected in bat tissues by gas chromatography/mass spectrometry (GC-MS) and quantified by gas chromatography tandem quadrupole mass spectrometry (GC-MS/MS). Concentrations of 4081 ppm DDT and 890 ppm DDE wet weight were found in the brain of one bat and are the highest reported concentrations in such a mortality event to date. This case emphasizes the importance of testing wildlife mortalities against a comprehensive panel of toxicologic agents including persistent organic pollutants in the absence of other more common disease threats.


Assuntos
Quirópteros/metabolismo , DDT/envenenamento , Monitoramento Ambiental/métodos , Inseticidas/envenenamento , Animais , Encéfalo/metabolismo , DDT/análise , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano/análise , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/análise , Montana , Envenenamento/metabolismo , Envenenamento/veterinária , Espectrometria de Massas em Tandem
13.
Life Sci ; 200: 81-86, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29551577

RESUMO

AIMS: To investigate whether intrauterine organochlorine pesticide (OCP)-dichlorodiphenyltrichloroethane (DDT) exposure could lead to epigenetic alterations by DNA methylation with possible important lifetime health consequences for offspring. MAIN METHODS: We used Illumina Infinium HumanMethylation 450 K BeadChip to explore the pattern of genome-wide DNA methylation containing >485,000 gene sites in cord blood of 24 subjects in a 12 mother-newborn pairs birth cohort. Based on the genome-wide DNA methylation data, we chose one potential gene, BRCA1, to verify the results in another group comprising 126 subjects. KEY FINDINGS: We identified 1,131 significantly different CpG sites which included 690 hypermethylation sites and 441 hypomethylation sites in the DNA methylation level between case and control group. The identified sites were located in 598 unique genes. In subsequent validation studies, we found that the DNA methylation level of the identified CpGs of BRCA1 increased with increased exposure to dichlorodiphenyltrichloroethane (DDT) and the level of gene expression in the identified CpGs of BRCA1 decreased with increased exposure to dichlorodiphenyltrichloroethane (DDT). SIGNIFICANCE: The results indicated that epigenetic processes played a possible role in the development of fetuses affected by maternal OCP-DDT exposure. Early prenatal exposure to DDT may affect fetal BRCA1 gene methylation, and increased exposure leads to a higher DNA methylation level and lower gene expression level.


Assuntos
Ilhas de CpG , Metilação de DNA/efeitos dos fármacos , Diclorodifenildicloroetano/toxicidade , Feto/metabolismo , Inseticidas/toxicidade , Exposição Materna/efeitos adversos , Adulto , Proteína BRCA1/biossíntese , Feminino , Feto/patologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Estudo de Associação Genômica Ampla , Humanos , Recém-Nascido , Masculino , Gravidez
15.
Environ Sci Process Impacts ; 20(1): 220-231, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29264604

RESUMO

Passive sampling is becoming a widely used tool for assessing freely dissolved concentrations of hydrophobic organic contaminants in environmental media. For certain media and target analytes, the time to reach equilibrium exceeds the deployment time, and in such cases, the loss of performance reference compounds (PRCs), loaded in the sampler before deployment, is one of the common ways used to assess the fractional equilibration of target analytes. The key assumption behind the use of PRCs is that their release is solely diffusion driven. But in this work, we show that PRC transformations in the sediment can have a measurable impact on the PRC releases and even allow estimation of that compound's transformation rate in the environment of interest. We found that in both field and lab incubations, the loss of the 13C 2,4'-DDT PRC from a polyethylene (PE) passive sampler deployed at the sediment-water interface was accelerated compared to the loss of other PRCs (13C-labeled PCBs, 13C-labeled DDE and DDD). The DDT PRC loss was also accompanied by accumulation in the PE of its degradation product, 13C 2,4'-DDD. Using a 1D reaction-diffusion model, we deduced the in situ degradation rates of DDT from the measured PRC loss. The in situ degradation rates increased with depth into the sediment bed (0.14 d-1 at 0-10 cm and 1.4 d-1 at 30-40 cm) and although they could not be independently validated, these rates compared favorably with literature values. This work shows that passive sampling users should be cautious when choosing PRCs, as degradation processes can affect some PRC's releases from the passive sampler. More importantly, this work opens up the opportunity for novel applications of passive samplers, particularly with regard to investigating in situ degradation rates, pathways, and products for both legacy and emerging contaminants. However, further work is needed to confirm that the rates deduced from model fitting of PRC loss are a true reflection of DDT transformation rates in sediments.


Assuntos
DDT/análise , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , China , Difusão , Monitoramento Ambiental/instrumentação , Recuperação e Remediação Ambiental , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Modelos Teóricos , Polietileno/química
16.
Bioresour Technol ; 243: 667-675, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28709072

RESUMO

Improving the stimulation effect of electric current density (ECD) on microbial community is critical in designing and operating TDE-BAF. This study investigated the effect of ECD at 0.00, 4.08, 6.12, 12.20, 14.25, 16.30 and 20.20A·m-2 on the removal performance, diversity and structure of microbial community in TDE-BAF. Results indicated that the ECD of 14.25A·m-2 exhibited the highest COD, TOC and NH4+-N average removal rates with 93.33%, 91.26% and 93.87%, respectively; Under high ECD, especially exceeding 14.25A·m-2, the inhibition of growth and activity because of plasmatorrhexis was in agreement with the sharp biomass decline; there was no significant relation between community richness and diversity and removal efficiency below optimum ECD, while above optimal ECD, it was just the opposite; Microbial communities mainly including Hydrogenophaga, Saprospiraceae_uncultured, Delftia, Enterobacter, Pseudomonas, Pseudoxanthomonas, and Nitrosospira and physicochemical properties well explained the excellent removal performance at the optimum ECD.


Assuntos
Reatores Biológicos , Eletrodos , Diclorodifenildicloroetano , Eletricidade , Filtração
18.
Curr Microbiol ; 74(9): 1068-1075, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28642970

RESUMO

DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) is one of the pesticides that are hazardous for the environment and human health. Effective environmental-friendly treatment using co-cultures of fungi and bacteria is needed. In this study, the bacteria Bacillus subtilis at various volumes of 1, 3, 5, 7, and 10 mL (1 mL ≈ 6.7 × 108 CFU) were mixed into 10 mL of the brown-rot fungus Fomitopsis pinicola culture for degrading DDT during a 7-days incubation period. DDT was degraded by approximately 42% by F. pinicola during the 7-days incubation period. The addition of 10 mL of B. subtilis into F. pinicola culture showed the highest DDT degradation of approximately 86% during the 7-days incubation period. DDD (1,1-dichloro-2,2-bis(4-chlorophenyl)ethane), DDE (1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene), and DDMU (1-chloro-2,2-bis(4-chlorophenyl)ethylene) were detected as metabolic products from DDT degradation by co-cultures of F. pinicola and B. subtilis. Transformation pathway was proposed in which DDT was transformed into three pathways as follows: (1) dechlorination to DDD, (2) dehydrochlorination to DDE, and (3) formation of DDMU.


Assuntos
Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/metabolismo , Coriolaceae/crescimento & desenvolvimento , Coriolaceae/metabolismo , DDT/metabolismo , Técnicas Microbiológicas/métodos , Reatores Biológicos/microbiologia , Biotransformação , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano/análise , Poluentes Ambientais/metabolismo , Redes e Vias Metabólicas , Praguicidas/metabolismo
19.
Zhonghua Yu Fang Yi Xue Za Zhi ; 50(11): 982-989, 2016 Nov 06.
Artigo em Chinês | MEDLINE | ID: mdl-27903362

RESUMO

Objective: To investigate the level of and factors influencing internal exposure to dichlorodiphenyltrichloroethane (DDT) in pregnant women. Methods: In all, 1 064 pregnant women were recruited in a hospital of Xiamen. Participants were asked to complete a questionnaire to obtain data on sociodemographic characteristics and lifestyle. Peripheral venous blood and cord blood samples were collected. Of the 1 064 pregnant women, 600 were enrolled in this study after completing the questionnaire and providing peripheral venous blood and cord blood. Among those women, 150 were selected randomly using a systematic sampling method. A gas chromatography coupled electron capture detector was used to determine the concentration of six DDT homologues: p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), o,p'-dichlorodiphenyltrichloroethane (o,p'-DDT), p,p'-dichlorodiphenyldichloroethane (p,p'-DDD), o,p'-dichlorodiphenyldichloroethane (o,p'-DDD), p,p'-dichlorodiphenylethylene (p,p'-DDE), and o,p'-dichlorodiphenylethylene (o,p'-DDE) . Pregnant women were divided into two groups according to DDT concentration: a low concentration group (detection value≤P50) and a high concentration group (detection value>P50). multivariate logistic regression was used to analyze the association between the DDT levels and potential influencing factors which investigated in the questionnaire. Results: The detection rates of p,p'-DDT, o,p'-DDT, p,p'-DDD, o,p'-DDD, p,p'-DDE and o,p'-DDE in the peripheral venous blood samples from the 150 pregnant women were 83.3% (125), 29.3% (44), 58.0% (87), 24.0% (36), 82.0% (123), and 34.7% (52), respectively. The median concentrations were 1.56, 0.03, 0.07, 0.03, 0.93 and 0.03 µg/ml, respectively. The detection rates of p,p'-DDT, o,p'-DDT, p,p'-DDD, o,p'-DDD, p,p'-DDE and o,p'-DDE in the cord blood samples were 69.3% (104), 10.7% (16), 29.3% (44), 20.7% (31), 81.3% (122) and 45.3% (68), and the median concentrations were 0.41, 0.03, 0.03, 0.03, 0.42 and 0.03 µg/ml, respectively. The concentration ranges in the low and high DDT concentration groups which contained 75 respondents respectively were 0-3.69 and 3.74-82.09 µg/ml, respectively. In the single-factor analysis, the number (percentage) of those who consumed seafood " rarely" , "less than twice a week" , and " twice a week or more" was 15 (20.3%), 22 (29.7%), and 37 (50.0%), respectively, in the low concentration group, and 4(5.3%), 20(26.7% ), and 51(68.0% ) in the high concentration group (χ2=8.69, P=0.013). The results of the multivariate logistic regression analysis indicate that pregnant women who consume seafood less than twice a week, twice a week or more have higher peripheral blood DDT concentrations compared with those who rarely consume seafood. The OR (95% CI) values were 1.14 (1.08-1.21), 2.11 (1.55-2.85), respectively. Conclusion: The exposure level of pregnant women to DDTs in the Xiamen area is higher than that of women in other regions. High seafood intake is a risk factor for internal exposure to DDTs.


Assuntos
Diclorodifenil Dicloroetileno/sangue , Exposição Ambiental/análise , Sangue Fetal/química , Placenta/química , Gestantes , Cromatografia Gasosa , DDT , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano/análise , Diclorodifenildicloroetano/sangue , Feminino , Humanos , Modelos Logísticos , Mitotano/análogos & derivados , Análise Multivariada , Gravidez
20.
Anal Chim Acta ; 942: 1-11, 2016 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-27720112

RESUMO

Silkworm (Bombyx mori) is a very useful target insect for evaluation of endocrine disruptor chemicals (EDCs) due to mature breeding techniques, complete endocrine system and broad basic knowledge on developmental biology. Comparative metabolomics of silkworms with and without EDC exposure offers another dimension of studying EDCs. In this work, we report a workflow on metabolomic profiling of silkworm hemolymph based on high-performance chemical isotope labeling (CIL) liquid chromatography mass spectrometry (LC-MS) and demonstrate its application in studying the metabolic changes associated with the pesticide dichlorodiphenyltrichloroethane (DDT) exposure in silkworm. Hemolymph samples were taken from mature silkworms after growing on diet that contained DDT at four different concentrations (1, 0.1, 0.01, 0.001 ppm) as well as on diet without DDT as controls. They were subjected to differential 12C-/13C-dansyl labeling of the amine/phenol submetabolome, LC-UV quantification of the total amount of labeled metabolites for sample normalization, and LC-MS detection and relative quantification of individual metabolites in comparative samples. The total concentration of labeled metabolites did not show any significant change between four DDT-treatment groups and one control group. Multivariate statistical analysis of the metabolome data set showed that there was a distinct metabolomic separation between the five groups. Out of the 2044 detected peak pairs, 338 and 1471 metabolites have been putatively identified against the HMDB database and the EML library, respectively. 65 metabolites were identified by the dansyl library searching based on the accurate mass and retention time. Among the 65 identified metabolites, 33 positive metabolites had changes of greater than 1.20-fold or less than 0.83-fold in one or more groups with p-value of smaller than 0.05. Several useful biomarkers including serine, methionine, tryptophan, asymmetric dimethylarginine, N-Methyl-D-aspartic and tyrosine were identified. The changes of these biomarkers were likely due to the disruption of the endocrine system of silkworm by DDT. This work illustrates that the method of CIL LC-MS is useful to generate quantitative submetabolome profiles from a small volume of silkworm hemolymph with much higher coverage than conventional LC-MS methods, thereby facilitating the discovery of potential metabolite biomarkers related to EDC or other chemical exposure.


Assuntos
Bombyx/metabolismo , Cromatografia Líquida/métodos , Hemolinfa/metabolismo , Marcação por Isótopo/métodos , Espectrometria de Massas/métodos , Metabolômica/métodos , Animais , Biomarcadores/metabolismo , Bombyx/efeitos dos fármacos , Diclorodifenildicloroetano/toxicidade , Hemolinfa/efeitos dos fármacos
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