RESUMO
DDT and metabolites were measured in six species of fish collected from the Tapajós River in the village of Barreiras, near the town of Itaituba in the Brazilian Amazon region. The selected fish were the most consumed and economically important to the local people. DDT was used frequently in this region for malaria control. Fish samples were analyzed after extraction by microwave-assisted extraction in hexane/acetone (8:2, v/v) by gas chromatography with electron capture detector. Residues of op'-DDT and pp'-DDT and metabolites were detected, including pp'-DDE, pp'-DDD, op'-DDT, and op'-DDE, in 98% of the samples, with a greater abundance of pp'-DDT. Total DDT levels were 7.1-249.5 ng g(-1) wet weight (w.w). The DDE/DDT ratio was low, indicating recent exposure to DDT. The study area that may be related to generated waste used in public health campaigns to combat mosquitos (Anopheles spp.), still present in the Amazon environment, that transmit malaria. DDT levels and metabolites found in fish species do not present risks to human health because they are below acceptable limits for consumption.
Assuntos
DDT/análise , Poluentes Ambientais/metabolismo , Peixes/metabolismo , Animais , Brasil , Cromatografia Gasosa , DDT/farmacocinética , Exposição Ambiental , Humanos , Malária/prevenção & controle , RiosAssuntos
DDT/toxicidade , Cadeia Alimentar , Inseticidas/toxicidade , Medição de Risco , Leões-Marinhos/fisiologia , Animais , Conservação dos Recursos Naturais , DDT/farmacocinética , Equador , Monitoramento Ambiental , Poluentes Ambientais/análise , Poluição Ambiental/análise , Inseticidas/farmacocinética , Fatores de RiscoRESUMO
The goal of the present study was to evaluate the role of Tamoxifen (TAM), in the distribution and/or elimination kinetics of o,p'-DDT, in male tilapias. A non-compartmental analysis was chosen to describe the time course of o,p'-DDT plasma concentrations. Mean plasma concentration of o,p'-DDT following IP administration indicates a very complex kinetic profile. Tamoxifen decreased the o,p'-DDT mean half-life (t½) from 20.38 to 16.11 days, the Mean Residence Time (MRT) from 28.7 to 23.23 days, and clearance (CL) from 0.0031 to 0.001 mL/min. The distribution pattern of o,p'-DDT in tissues and the clearance in plasma suggest that storage points mediated through the membrane-receptor lipophilicity can be involved.
Assuntos
Ciclídeos/sangue , DDT/farmacocinética , Disruptores Endócrinos/farmacocinética , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Tamoxifeno/farmacologia , Animais , DDT/sangue , DDT/toxicidade , Disruptores Endócrinos/sangue , Disruptores Endócrinos/toxicidade , Meia-Vida , Masculino , Taxa de Depuração Metabólica , Distribuição TecidualRESUMO
DDT and Lindane (gamma-HCH) which were used until 1999 in Mexico, have provided great benefits in the combat of vectors that spread infection-borne diseases and in agriculture for crop protection. The persistence in the environment and their accumulative properties results in bioconcentration in lipid rich tissues of the human body that reflect the extent of environmental pollution. Human adipose tissue samples were taken during 2009 from abdominal cavities of 69 pregnant women by cesarean surgery and from 34 samples of control donors by autopsy in Veracruz State. The samples were analyzed by gas chromatography with ECD. The results of mean levels (mg/kg on fat basis) were higher in controls compared to pregnant women beta-HCH 0.064 vs 0.027; pp'DDE 1.187 vs. 0.745; op'DDT 0.016 vs. 0.011; pp'DDT 0.117 vs. 0.099 and Sigma-DDT 1.337 vs. 0.854. The pregnant women group was divided according to age: up to 20, 20-30, and more than 30 years, and presented an increase for the more persistent pesticides with age in terms of mean concentrations and a more pronounced higher correlation in medians levels. Pairing Body Mass Index to organochlorine pesticide mean levels revealed no correlation between these factors in pregnant women.
Assuntos
Gordura Abdominal/metabolismo , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Exposição Materna , Praguicidas/análise , Adulto , Fatores Etários , Idoso , Estudos de Casos e Controles , Cesárea , Cidades , DDT/análise , DDT/farmacocinética , Monitoramento Ambiental , Poluentes Ambientais/farmacocinética , Feminino , Hexaclorocicloexano/análise , Hexaclorocicloexano/farmacocinética , Humanos , Hidrocarbonetos Clorados/farmacocinética , México , Pessoa de Meia-Idade , Praguicidas/farmacocinética , Gravidez , Adulto JovemRESUMO
The relationship of dichlorodiphenyltrichloroethane (DDT) exposure and breast cancer risk has received increasing attention since the beginning of the 1990s. Contradicting published results regarding the relationship between body burden levels of p,p'-dichlorodiphenyldichloroethane (p,p'-DDE)--the main DDT metabolite--and breast cancer, we argue that such differences stem from methodologic differences among those studies. We performed a meta-analysis of 22 articles using DerSimonian and Laird's method for random effects models. The Q-statistic was used to identify heterogeneity in the outcome variable across studies. The gradient of p,p'-DDE exposure in epidemiologic studies was homogenized to serum lipid bases (nanograms per gram). The potential for publication bias was examined by means of the Begg's test. We discuss methodologic features of the studies in an attempt to reconcile the findings. The summary odds ratio (OR) for selected studies was 0.97 (95% confidence interval, 0.87-1.09) and the gradient of exposure ranged from 84.37 to 12,948 ng/g. No overall heterogeneity in the OR was observed (chi-squared = 27.93; df = 23; p = 0.218). Neither the study design nor the lack of breast-feeding control or the type of biologic specimen used to measure p,p'-DDE levels were the causes of heterogeneity throughout the studies. Evidence for publication bias was not found (p = 0.253). Overall, these results should be regarded as a strong evidence to discard the putative relationship between p,p'-DDE and breast cancer risk. Nevertheless, the exposure to DDT during critical periods of human development--from conception to adolescence--and individual variations in metabolizing enzymes of DDT or its derivatives are still important areas to be researched in regard to breast cancer development in adulthood.
Assuntos
Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/epidemiologia , DDT/farmacocinética , DDT/intoxicação , Diclorodifenil Dicloroetileno/farmacocinética , Diclorodifenil Dicloroetileno/intoxicação , Exposição Ambiental , Poluentes Ambientais/farmacocinética , Poluentes Ambientais/intoxicação , Inseticidas/farmacocinética , Inseticidas/intoxicação , Efeitos Tardios da Exposição Pré-Natal , Adolescente/fisiologia , Adulto , Criança , Pré-Escolar , Fatores de Confusão Epidemiológicos , Estudos Epidemiológicos , Feminino , Humanos , Lactente , Recém-Nascido , Razão de Chances , Gravidez , Reprodutibilidade dos Testes , Projetos de Pesquisa , Medição de Risco , Distribuição TecidualAssuntos
DDT/efeitos adversos , Infertilidade Masculina/etiologia , Inseticidas/efeitos adversos , Malária/prevenção & controle , Adolescente , Adulto , Androgênios/sangue , Carga Corporal (Radioterapia) , DDT/farmacocinética , Humanos , Inseticidas/farmacocinética , Masculino , México , Distribuição TecidualAssuntos
Tecido Adiposo/química , Inseticidas/análise , Leite Humano/química , Resíduos de Praguicidas/análise , Tecido Adiposo/metabolismo , DDT/análise , DDT/farmacocinética , DDT/toxicidade , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/farmacocinética , Diclorodifenil Dicloroetileno/toxicidade , Diclorodifenildicloroetano/análise , Diclorodifenildicloroetano/farmacocinética , Diclorodifenildicloroetano/toxicidade , Feminino , Fungicidas Industriais/análise , Fungicidas Industriais/farmacocinética , Fungicidas Industriais/toxicidade , Hexaclorobenzeno/análise , Hexaclorobenzeno/farmacocinética , Hexaclorobenzeno/toxicidade , Hexaclorocicloexano/análise , Hexaclorocicloexano/farmacocinética , Hexaclorocicloexano/toxicidade , Humanos , Inseticidas/farmacocinética , Inseticidas/toxicidade , México , Resíduos de Praguicidas/farmacocinética , Resíduos de Praguicidas/toxicidadeRESUMO
1. The influence of nutritional state over topical insecticidal activity of DDT in nymph II of Triatoma infestans was analyzed. 2. DDT LD50 for starved nymph II was more than 150 micrograms/insect, while for nymph II fed to repletion on artificial feeder, was 0.79(0.50-3.13) micrograms/insect and a similar result was obtained for nymph II fed on pigeons (1.09(0.36-7.55) micrograms/insect). 3. A very slow penetration rate of 14C-DDT was obtained in non fed insects (4.4% penetrated 46 hr after treatment) in correspondence with 0% of mortality. 8.5% of 14C-DDT was not recovered from the cuticle 2 hr after topication of fed nymph in correspondence with a 100% of mortality at 24 hr.
Assuntos
DDT/farmacocinética , Triatoma/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dose Letal MedianaAssuntos
DDT/toxicidade , Estrogênios/sangue , Animais , DDT/farmacocinética , Feminino , Meia-Vida , Isomerismo , Ratos , Ratos Endogâmicos , Útero/citologia , Útero/efeitos dos fármacosRESUMO
The present study examines electrophysiological alterations in the blood brain barrier of the American cockroach when the solvent hexane-acetone is applied topically to the ventral nerve cord. Rupture of the barrier was evaluated by perfusion with saline in which NaCl was replaced with choline chloride at 28 degrees and 15 degrees C. The electrophysiological effects of an ethanol DDT suspension on the ventral nerve cord previously treated with hexane-acetone at 28 degrees C and 15 degrees C were consistent with the rupture of the blood brain barrier and the negative temperature coefficient of DDT toxicity.