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1.
J Biochem Mol Toxicol ; 36(11): e23191, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35946146

RESUMO

Although studies have suggested organochlorine pesticides (OCPs) exposure increased the risk of epithelial ovarian cancer, the mechanisms underlying its potential tumorigenic effects in the human ovary are not well understood. In this study, we investigated the impact of dichlorodiphenyldichloroethylene (DDE), endosulfan, and heptachlor exposure on epithelial cadherin (E-cadherin) and proinflammatory mediators in human ovary surface epithelial (HOSE) cells. We found that DDE, endosulfan, and heptachlor exposure resulted in epithelial differentiation accompanied by upregulation of E-cadherin expression and overexpression of proinflammatory cytokines (TNFα, IL-1ß, and IL-6) in HOSE cells. The epithelial differentiation may accelerate HOSE cells to inclusion body formation, a common site for ovarian cancer initiation and persistent exposure to OCPs creates a chronic inflammatory microenvironment that may promote the neoplastic transformation of HOSE cells within the inclusion cyst.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Humanos , Feminino , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/metabolismo , Endossulfano/toxicidade , Ovário/metabolismo , Mediadores da Inflamação/metabolismo , Hidrocarbonetos Clorados/toxicidade , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/metabolismo , Praguicidas/toxicidade , Praguicidas/metabolismo , Heptacloro/análise , Heptacloro/metabolismo , Células Epiteliais/metabolismo , Caderinas/metabolismo
2.
Bull Environ Contam Toxicol ; 99(1): 89-92, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28540444

RESUMO

One hundred samples of mother breast milk were gathered from six middle governorates and districts in Jordan in 2013/2014 to monitor Organochlorine pesticides pollutants. The results showed clearly that banned organochlorine pesticides are still detected in the monitored samples in low concentration despite banning of these persistent pollutants in Jordan since 36 years ago. However, the results indicated that 1% of the contaminated samples contained ß-HCH, 5% γ-HCH, 3% p,p'-DDD, 2% heptachlor, 45% p,p'-DDE and 3% p,p'-DDT. In addition, these monitored samples had no residues of aldrin, dieldrin, α-endosulfan, ß-endosulfan, HCB, o,p'-DD, o,p'-DDT and o,p'-DDE. In conclusion, there was a decline in the residues of Organochlorine pesticides, particularly DDT group members.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Hidrocarbonetos Clorados/metabolismo , Leite Humano/metabolismo , Resíduos de Praguicidas/metabolismo , Praguicidas/metabolismo , Aldrina/análise , Aldrina/metabolismo , DDT , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/metabolismo , Dieldrin/análise , Dieldrin/metabolismo , Endossulfano/análise , Endossulfano/metabolismo , Heptacloro/análise , Heptacloro/metabolismo , Hexaclorocicloexano/metabolismo , Humanos , Hidrocarbonetos Clorados/análise , Jordânia , Leite Humano/química , Mitotano/análogos & derivados , Mitotano/metabolismo , Resíduos de Praguicidas/análise , Praguicidas/análise
3.
Bull Environ Contam Toxicol ; 97(2): 191-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27329111

RESUMO

Mussel samples were collected monthly between October-2010 and October-2011 from four stations (Bosphorus, Bandirma, Gelibolu, Tekirdag) in the Marmara Sea. Two consecutive months' samples were homogenized and combined as a single group for analysis. Mussel samples were analyzed for Organochlorine pesticides (OCPs); (total-DDT, total-HCH, Endrin, α-Endosulfan, ß-Endosulfan, Heptachlor) and Polychlorinated biphenyls (PCBs); (PCB 28, PCB 52, PCB 138, PCB 153, and PCB 180). All analyses were done according to Eurofins house method in ERGO Laboratory in Germany. Concentrations of α-endosulfan and heptachlor in mussel tissues were below method detection limits. The annual average OCPs concentrations among the stations ranged between 0.02 and 1.45 ng/g (wet weight), 1.9-99.75 ng/g (lipid weight) whereas the annual average PCBs concentrations among the stations ranged between 0.03 and 0.40 ng/g (wet weight), 1.71-26.48 ng/g (lipid weight), respectively. There was no relation between fat content of mussels and residues of the contaminants. PCB 138 and PCB 153 were the most predominant PCBs, while total-DDT and total-HCH were the most predominant OCPs in the mussels. Total-DDT concentrations were higher compared to total-HCH and PCBs isomers. Measured levels were below the national and international committees' and institutions' limits for human consumption and protection of aquatic biota.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados/metabolismo , Mytilus/metabolismo , Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Endossulfano/análise , Endossulfano/metabolismo , Alemanha , Heptacloro/análise , Heptacloro/metabolismo , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise
4.
Environ Sci Pollut Res Int ; 21(19): 11305-12, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24840358

RESUMO

The ability of certain white-rot fungi (WRF) inocula to transform heptachlor and heptachlor epoxide and its application in artificially contaminated soil were investigated. Fungal inoculum of Pleurotus ostreatus eliminated approximately 89 % of heptachlor after 28 days of incubation, and chlordene was detected as the primary metabolite. The fungal inoculum of Pleurotus ostreatus had the highest ability to degrade heptachlor epoxide; approximately 32 % were degraded after 28 days of incubation, and heptachlor diol was detected as the metabolite product. Because Pleurotus ostreatus transformed heptachlor into a less toxic metabolite and could also effectively degrade heptachlor epoxide, it was then selected to be applied to artificially contaminated soil. The spent mushroom waste (SMW) of Pleurotus ostreatus degraded heptachlor and heptachlor epoxide by approximately 91 and 26 %, respectively, over 28 days. This finding indicated that Pleurotus ostreatus SMW could be used to bioremediate heptachlor- and heptachlor epoxide-contaminated environments.


Assuntos
Heptacloro Epóxido/metabolismo , Heptacloro/metabolismo , Inseticidas/metabolismo , Pleurotus/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental
5.
Environ Sci Pollut Res Int ; 21(10): 6303-13, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23338993

RESUMO

Human serum samples (n = 113) from Bizerte, northern Tunisia, collected between 2011 and 2012 were analyzed for 8 organochlorine pesticides (OCPs) including p,p'-dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), hexachlorocyclohexane isomers, dieldrin, and heptachlor and 12 polychlorinated biphenyls (PCBs) congeners. Concentrations of these residues in serum were determined by gas chromatography with electron capture detector and total cholesterol (CHOL) and triglycerides (TG) levels were evaluated by enzymatic colorimetric method. HCB, p,p'-DDE, PCB-138, PCB-153, and PCB-180, were the most abundant organochlorine compounds (OCs) detected in >95 % of the study subjects. The mean levels of p,p'-DDE and HCB in serum were 168.8 and 49.1 ng g(-1) lipid, respectively. The sum PCBs concentrations ranged from 37.5 to 284.6 ng g(-1) lipid in the samples, with mean and median value of 136.1 and 123.2 ng g(-1) lipid, respectively. The PCB profile consisted of persistent congeners, such as PCB-138, PCB-153, and PCB-180 which contributed for approximately 82.7 % to the ∑PCBs. Statistical analysis showed that most OCs correlated significantly with age, considering all samples together or with gender differentiation. The present study shows that the levels of p,p'-DDE and ∑DDTs were significantly higher in females than in males (p < 0.05), while PCBs levels were significantly higher in male (p < 0.05) than in females. No statistically significant association was found between body mass index and concentration of any organochlorine pesticide or PCB congeners 153, 138, 180, or ∑PCBs.


Assuntos
Índice de Massa Corporal , Exposição Ambiental/análise , Poluentes Ambientais/sangue , Hidrocarbonetos Clorados/sangue , Praguicidas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , DDT/metabolismo , Diclorodifenil Dicloroetileno/metabolismo , Exposição Ambiental/estatística & dados numéricos , Feminino , Heptacloro/metabolismo , Hexaclorobenzeno/análise , Hexaclorocicloexano/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Bifenilos Policlorados/metabolismo , Tunísia , Adulto Jovem
6.
Environ Sci Technol ; 47(15): 8913-22, 2013 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-23799267

RESUMO

Chlordane, heptachlor, and their metabolites are chiral persistent organic pollutants that undergo enantiomeric enrichment in the environment. This study investigated the enantioselective metabolism of both chlordane isomers and heptachlor, major components of technical chlordane, by liver microsomes prepared from male rats treated with corn oil (CO) or inducers of CYP2B (PB; phenobarbital) and CYP3A enzymes (DX; dexamethasone), isoforms induced by chlordane treatment. The extent of the metabolism of all three parent compounds was dependent on the microsomal preparation used and followed the rank order PB > DX > CO. The mass balances ranged from 49 to 130% of the parent compound added to the microsomal incubations. Both cis- and trans-chlordane were enantioselectively metabolized to oxychlordane (EF = 0.45-0.89) and 1,2-dichlorochlordene (EF = 0.42-0.90). Heptachlor was metabolized enantioselectively, with heptachlor epoxide B (EF = 0.44-0.54) being the only metabolite. Interestingly, the direction on the enrichment for oxychlordane, 1,2-dichlorochlordene, and heptachlor epoxide differed depending on the microsomal preparation. These findings demonstrate that the direction and extent of the enantioselective metabolism of both chlordane isomers and heptachlor is P450 isoform-dependent and can be modulated by the induction of P450 enzymes.


Assuntos
Clordano/metabolismo , Heptacloro/metabolismo , Inseticidas/metabolismo , Microssomos Hepáticos/metabolismo , Animais , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Ratos , Estereoisomerismo
7.
Bull Environ Contam Toxicol ; 89(5): 995-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22996652

RESUMO

The green mussel, Perna viridis, was used to measure bioaccumulated levels of organochlorine pesticides in the marine environment of Cuba. Samples were collected in the Cienfuegos Bay between January and December 2010. The organochlorine pesticides (i.e. DDT, Dieldrin, Chlordane, Endosulfan, HCB, Aldrin, Heptachlor and Lindane) were quantified by gas chromatography. The sum of all organochlorine pesticides in P. viridis was 6.31 ng g(-1). The concentration ranged from 3.53 to 4.42 ng g(-1) dry weight (dw) for DDTs (i.e. sum of pp' DDT, pp' DDD, op' DDE and pp' DDE); 1.7-1.9 ng g(-1) dw for Dieldrin; 0.17-0.20 ng g(-1) dw for Chlordanes; 0.14-0.16 ng g(-1) dw for Endosulfan; 0.11-0.17 ng g(-1) dw for HCB; 0.07-0.11 ng g(-1) dw for Aldrin; 0.046-0.054 ng g(-1) dw for Heptachlor and 0.035-0.039 ng g(-1) dw for Lindane. These levels can be considered as low when compared to reported values from similar studies conducted elsewhere in the world. The concentrations of all organochlorines residues detected in this study fell below the EU Maximum Residue Limits.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados/metabolismo , Perna (Organismo)/metabolismo , Praguicidas/metabolismo , Poluentes Químicos da Água/metabolismo , Aldrina/metabolismo , Animais , Baías/química , Cuba , Diclorodifenil Dicloroetileno/metabolismo , Dieldrin/metabolismo , Endossulfano/metabolismo , Heptacloro/metabolismo , Hexaclorobenzeno/metabolismo , Hexaclorocicloexano/metabolismo , Poluição Química da Água/estatística & dados numéricos
8.
Chemosphere ; 84(3): 318-27, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21550627

RESUMO

The surface sediments, two bivalves (Arca senilis and Crassostera gasar) and three gastropods (Conus spp., Hexaplex duplex and Pugilina morio) from two Senegalese stations, Falia (Sine-Saloum Estuary) and Fadiouth (Petite Côte), were analyzed for their pollutant organic persistent contamination (polychlorinated biphenyls PCBs; organochlorinated pesticides OCPs; polybrominated diphenyl ethers PBDEs). Results revealed significant levels of PCBs, DDTs and lindane in mangrove sediments ranging from 0.3 to 19.1, 0.3 to 15.9, and 0.1 to 1.9 ng g(-1) d.w., respectively. Among the other POPs analysed, only hexachlorobenzene, heptachlor and trans-nonachlor for OCPs, as well as BDE47 and BDE99 congeners for PBDEs were detected at very low concentrations, generally not of concern. POP levels and patterns were in good accordance with literature data available for other tropical developing countries. A seasonal quantitative difference was highlighted with higher levels of PCBs and DDTs in sediments after the wet season, likely due to the strong wash-out of residues from inland to the marine ecosystems during the rainy season. The observed pattern of DDT and its metabolites pointed out probable recent applications of DDT for public health emergencies in Senegal. Exploited molluscs were exposed to the same POP compounds as those measured in sediments. They presented OCP levels within the same range as in sediments, while significant higher concentrations of PCBs were observed in shellfish soft tissues revealing a higher bioaccumulation potential mainly due to the lipophilicity of these compounds. Finally, the influence of the reproduction cycle on POP levels through lipid content variations was highlighted, minimizing potential differences in POP bioaccumulation between shellfish species. From an ecotoxicological and public health point of view, results from this study revealed that POPs in sediments from the Petite Côte and the Sine-Saloum Estuary would not cause toxic effects and impairments in molluscs from these regions, and that no potential risk exists for human, especially local populations, through mangrove shellfish consumption.


Assuntos
Bivalves/metabolismo , Gastrópodes/metabolismo , Compostos Orgânicos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Ecossistema , Monitoramento Ambiental , Pesqueiros/estatística & dados numéricos , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/metabolismo , Heptacloro/análise , Heptacloro/metabolismo , Hexaclorobenzeno/análise , Hexaclorobenzeno/metabolismo , Hexaclorocicloexano/análise , Hexaclorocicloexano/metabolismo , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/metabolismo , Compostos Orgânicos/análise , Praguicidas/análise , Praguicidas/metabolismo , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Rhizophoraceae , Estações do Ano , Senegal , Poluentes Químicos da Água/análise
9.
Chemosphere ; 83(7): 891-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21440927

RESUMO

The contamination status of the marine environment in Hong Kong was studied by measuring concentrations of organochlorine (OC) pollutants (i.e., hexachlorobenzene, aldrin, dieldrin, endrin, mirex, total heptachlor, total chlordane, total DDTs, total PCBs, and total toxaphenes) in the eggs of selected waterbird species from different locations around the city: Little Egret (Egretta garzetta) and Chinese Pond Heron (Ardeola bacchus) from Mai Po Village, Great Egret (Ardea alba) and Black-crowned Night Heron (Nycticorax nycticorax) from A Chau, and Chinese Pond Heron (A. bacchus) from Ho Sheung Heung. The mean concentrations of total PCBs and total DDTs ranged from 191-11,100 ng g(-1) lipid and 453-49,000 ng g(-1) lipid, respectively. Recent exposure of waterbirds to technical chlordane was found in Hong Kong. The risk characterization demonstrated potential risks to birds associated with exposure to DDE, which was found to cause a reduction in survival of young in Hong Kong Ardeids based on the endpoint in the risk assessment.


Assuntos
Aves/metabolismo , Poluentes Ambientais/metabolismo , Óvulo/metabolismo , Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Aldrina/metabolismo , Animais , Clordano/metabolismo , DDT/metabolismo , Dieldrin/metabolismo , Endrin/metabolismo , Monitoramento Ambiental , Poluição Ambiental/estatística & dados numéricos , Heptacloro/metabolismo , Hexaclorobenzeno/metabolismo , Hong Kong , Hidrocarbonetos Clorados/metabolismo , Mirex/metabolismo , Medição de Risco
10.
FEMS Microbiol Lett ; 314(2): 140-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21087297

RESUMO

White rot fungi of the genus Phlebia have demonstrated a high capacity to degrade organic pollutants, including polychlorinated dibenzo-p-dioxins and polychlorinated biphenyls. In this study, we evaluated the ability of 18 white rot fungi species of genus Phlebia to degrade heptachlor and heptachlor epoxide, and described the metabolic pathways by selected white rot fungi. Phlebia tremellosa, Phlebia brevispora and Phlebia acanthocystis removed about 71%, 74% and 90% of heptachlor, respectively, after 14 days of incubation. A large amount of heptachlor epoxide and a small amount of 1-hydroxychlordene and 1-hydroxy-2,3-epoxychlordene were detected as metabolic products of heptachlor from most fungal cultures. The screening of heptachlor epoxide-degrading fungi revealed that several fungi are capable of degrading heptachlor epoxide, which is a recalcitrant metabolite of heptachlor. Phlebia acanthocystis, P. brevispora, Phlebia lindtneri and Phlebia aurea removed about 16%, 16%, 22% and 25% of heptachlor epoxide, respectively, after 14 days of incubation. Heptachlor diol and 1-hydroxy-2,3-epoxychlordene were produced in these fungal cultures as metabolites, suggesting that the hydrolysis and hydroxylation reaction occur in the epoxide ring and in position 1 of heptachlor epoxide, respectively.


Assuntos
Basidiomycota/metabolismo , Heptacloro Epóxido/metabolismo , Heptacloro/metabolismo , Praguicidas/metabolismo , Biotransformação , Indenos/metabolismo , Fatores de Tempo
11.
Environ Pollut ; 157(8-9): 2493-506, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19362400

RESUMO

During a decade (1996-2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp'-DDE, dieldrin, aldrin, heptachlor, endosulfan...) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas.


Assuntos
Organismos Aquáticos/metabolismo , Cadeia Alimentar , Hidrocarbonetos Clorados/metabolismo , Água do Mar/química , Poluentes Químicos da Água/metabolismo , Aldrina/análise , Aldrina/metabolismo , Animais , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/metabolismo , Dieldrin/análise , Dieldrin/metabolismo , Endossulfano/análise , Endossulfano/metabolismo , Monitoramento Ambiental , França , Heptacloro/análise , Heptacloro/metabolismo , Hexaclorocicloexano/análise , Hexaclorocicloexano/metabolismo , Hidrocarbonetos Clorados/análise , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/análise , Áreas Alagadas
12.
Insect Biochem Mol Biol ; 38(11): 1008-15, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18930820

RESUMO

The interactions of protein components of the xenobiotic-metabolizing cytochrome P450 system, CYP6A1, P450 reductase, and cytochrome b5 from the house fly (Musca domestica) have been characterized. CYP6A1 activity is determined by the concentration of the CYP6A1-P450 reductase complex, regardless of which protein is present in excess. Both holo- and apo-b5 stimulated CYP6A1 heptachlor epoxidase and steroid hydroxylase activities and influenced the regioselectivity of testosterone hydroxylation. The conversion of CYP6A1 to its P420 form was decreased by the addition of apo-b5. The effects of cytochrome b5 may involve allosteric modification of the P450 enzyme that modify the conformation of the active site. The overall stoichiometry of the P450 reaction was substrate-dependent. High uncoupling of CYP6A1 was observed with generation of hydrogen peroxide, in excess over the concomitant testosterone hydroxylation or heptachlor epoxidation. Inclusion of cytochrome b5 in the reconstituted system improved efficiency of oxygen consumption and electron utilization from NADPH, or coupling of the P450 reaction. Depending on the reconstitution conditions, coupling efficiency varied from 8 to 25% for heptachlor epoxidation, and from 11 to 70% for testosterone hydroxylation. Because CYP6A1 is a P450 involved in insecticide resistance, this suggests that xenobiotic metabolism by constitutively overexpressed P450s may be linked to significant oxidative stress in the cell that may carry a fitness cost.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Citocromos b5/metabolismo , Moscas Domésticas/enzimologia , Proteínas de Insetos/metabolismo , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Animais , Catálise , Cromatografia Líquida de Alta Pressão , Heptacloro/metabolismo , Moscas Domésticas/metabolismo , Hidroxilação , Testosterona/metabolismo
13.
Neurotoxicology ; 29(5): 855-63, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18577399

RESUMO

Parkinson's disease (PD) is primarily thought of as a disease of aging. However, recent evidence points to the potential for exposure to xenobiotics during development to increase risk of PD. Here, we report that developmental exposure to the organochlorine pesticide heptachlor alters the dopamine system and increases neurotoxicity in an animal model of PD. Exposure of pregnant mice to heptachlor led to increased levels of the dopamine transporter (DAT) and vesicular monoamine transporter 2 (VMAT2) levels at both the protein and mRNA level in their offspring. Increased DAT and VMAT2 levels were accompanied by alterations of mRNA levels of nuclear transcription factors that control dopamine neuron development and regulate DAT and VMAT2 levels in adulthood. At 12 weeks of age, control and heptachlor-exposed offspring were administered a moderate dose (2 x 10mg/kg) of the parkinsonism-inducing agent MPTP. Greater neurotoxicity as evidenced by a greater loss of striatal dopamine and potentiation of increased levels of glial fibrillary acidic protein and alpha-synuclein was observed in heptachlor-exposed offspring. The neurotoxicity observed was greater in the male offspring than the female offspring, suggesting that males are more susceptible to the long-term effects of developmental heptachlor exposure. These data suggest that developmental heptachlor exposure causes long-term alterations of the dopamine system thereby rendering it more susceptible to dopaminergic damage in adulthood.


Assuntos
Dopamina/metabolismo , Heptacloro/toxicidade , Intoxicação por MPTP/patologia , Neurônios/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Análise de Variância , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Heptacloro/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Gravidez , Fatores Sexuais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/genética , Proteínas Vesiculares de Transporte de Monoamina/metabolismo
14.
J Environ Sci Health B ; 41(5): 553-69, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16785166

RESUMO

Degradation of aldrin (1,2,3,4,10,10-Hexachloro-1,4,4a,5,8,8a-hexahydro-1,4:5-8-dimethanonaphthalene), heptachlor (1H-1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methano indene), dieldrin (1aalpha,2beta,2aalpha,3beta,6beta,6aalpha,7beta,7aalpha)-3,4,5,6,9,9-Hexachloro-1a,2,2a,3,6,6a,7,7a-octahydro-2,7:3,6-d-methanonaphtha[2,3-b]oxirene, and heptachlor epoxide (1aalpha, 1bbeta,2alpha,5alpha,5alphabeta,6beta,6aalpha-2,3,4,5,6,7,7-Heptachloro-1a,1b,5,5a,6,6a-hexahydro-2,5-methano-2H-inden[1,2-b]-oxirene) was tested using free cultures of Pseudomonas fluorescens under controlled conditions. Pesticide concentrations were monitored by gas chromatography during 120 h. Percentages of degradation and biodegradation rates (BDR) were calculated. Data showed a trend suggesting a relation between chemical structure and degradability. Degradation kinetics for each pesticide tested showed that the highest degradation rates were found in the first 24 h. Kinetics data were adjusted to an empirical equation in order to predict their behavior, and the correlation coefficients obtained were satisfactory. Gas chromatography/mass spectrometry (GC/MS) analysis of the final extracts allowed the identification of chlordene and monodechlorodieldrin, which have been reported as final metabolite produced in the biodegradation of this kind of compounds. Regarding adsorption of pesticides on activated vegetal carbon, we concluded that removal efficiencies between 95.45 and 97.18% can be reached, depending on the pesticide and the carbon dose applied. The values for K from the Freundlich equation were quite similar for the four pesticides (between 1.0001 and 1.04), whereas the n values were quite different for each pesticide in the following order of affinity: dieldrin > aldrin > heptachlor epoxide > heptachlor. Equilibrium times, very important for scaling up the process, were between 43 min and 1 h, for the heptachlor epoxide and the heptachlor, respectively.


Assuntos
Carvão Vegetal/química , Inseticidas/química , Inseticidas/metabolismo , Pseudomonas fluorescens/metabolismo , Adsorção , Aldrina/análise , Aldrina/química , Aldrina/metabolismo , Biodegradação Ambiental , Cromatografia Gasosa , Dieldrin/análise , Dieldrin/química , Dieldrin/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Heptacloro/análise , Heptacloro/química , Heptacloro/metabolismo , Heptacloro Epóxido/análise , Heptacloro Epóxido/química , Heptacloro Epóxido/metabolismo , Inseticidas/análise , Cinética , Microbiologia do Solo , Poluentes do Solo/análise
16.
Toxicology ; 188(2-3): 125-37, 2003 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-12767685

RESUMO

One approach to the toxicological evaluation of chemical mixtures is to construct full dose-response curves for each compound in the presence of a range of doses of each of the other compounds, i.e., a factorial design. This study was undertaken as part of an interdisciplinary project to evaluate a mixture of three environmental pollutants. A full-factorial design was undertaken to determine the neurobehavioral consequences of short-term repeated exposure to five dose levels each of three chemicals, in order to characterize potential two- and three-way interactions. Adult female F344 rats received (p.o.) for 10 days either one of five doses of trichloroethylene, di(2-ethylhexyl)phthalate, or heptachlor, or else one of all possible chemical combinations. Neurobehavioral evaluations were conducted using motor activity and an abbreviated functional observational battery. Response-surface analysis was applied to each of the endpoints. Hypotheses were tested based on the estimated model parameters; of primary interest was the overall test for interaction among the three chemicals. In addition, an abbreviated design was created by fitting only a subset of the data to the model. In general, significant overall interactions that deviated from response additivity were detected for most endpoints (11 of 14). All of the interactions on the neurobehavioral endpoints showed either antagonism, or else an interaction that could not be fully characterized. Often the results of the abbreviated dataset analysis were not the same as for the full-factorial design. This study was extremely intensive, in terms of the number of rats and time required for conduct of the study as well as the data analysis. These results underscore the need for more economical approaches to evaluate the toxic effects of mixtures of chemicals.


Assuntos
Dietilexilftalato/toxicidade , Heptacloro/toxicidade , Inseticidas/toxicidade , Tricloroetileno/toxicidade , Animais , Dietilexilftalato/metabolismo , Exposição Ambiental/efeitos adversos , Feminino , Marcha/efeitos dos fármacos , Marcha/fisiologia , Heptacloro/metabolismo , Inseticidas/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Modelos Estatísticos , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Análise Multivariada , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344 , Solventes/metabolismo , Solventes/toxicidade , Testes de Toxicidade/métodos , Tremor/induzido quimicamente , Tricloroetileno/metabolismo
17.
Toxicol Sci ; 61(1): 164-75, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11294987

RESUMO

This study was performed to determine if developmental exposure of rats to heptachlor (H) during the last half of gestation through puberty adversely affects adult functioning of the immune and reproductive systems. Time-bred pregnant female Sprague-Dawley rats were dosed by gavage with H (0, 30, 300, or 3000 microg/kg/day) from gestation day (GD) 12 to postnatal day (PND) 7, followed by direct dosing of the pups with H through PND 42. Separate groups of rats were evaluated with a battery of immune function tests, while other groups of rats were evaluated for reproductive development and function. Additional groups of rats were euthanized at the end of the dosing period for histological analyses of major organ systems. Some dams and PND 7 pups were euthanized; milk, plasma, fat and/or tissues were assayed for H and heptachlor epoxide B (HEB), a major metabolite of H. The amount of H and HEB found in milk, blood, fat, and tissues was proportional to the dose of H administered. There were no effects on the number or survival of pups born to H-exposed dams nor to pups exposed postnatally. There were no effects on the number of treated dams delivering litters or on litter size, nor were there any effects on any of the reproductive end points examined in the F(0) or F(1) rats. There were no effects of H exposure on lymphoid organ weights, splenic natural killer (NK) cell activity, and splenic lymphoproliferative (LP) responses to mitogens and allogeneic cells in a mixed lymphocyte response (MLR) assay at 8 weeks of age. H exposure did not alter delayed or contact hypersensitivity at 10 or 17 weeks of age, respectively. However, the primary IgM antibody response to sheep red blood cells (SRBCs) was suppressed in a dose-dependent manner in males, but not females, at 8 weeks of age. The percentage of B lymphocytes (OX12(+)OX19(-)) in spleen was also reduced in the high-dose males. The anti-SRBC IgM response was reduced only in males exposed to 30 microg H/kg/day in a separate group of rats 21 weeks of age. In these same rats, at 26 weeks of age, the secondary IgG antibody response to SRBCs was suppressed in all of the H-exposed males, but not females. These data indicate that perinatal exposure of male rats to H results in suppression of the primary IgM and secondary IgG anti-SRBC responses. Suppression of these antibody responses persisted for up to 20 weeks after the last exposure to H, at a total exposure of approximately 1500 microg H/kg/rat.


Assuntos
Heptacloro/toxicidade , Sistema Imunitário/efeitos dos fármacos , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Reprodução/efeitos dos fármacos , Maturidade Sexual/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Formação de Anticorpos/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Idade Gestacional , Heptacloro/administração & dosagem , Heptacloro/análise , Heptacloro/metabolismo , Heptacloro Epóxido/análise , Heptacloro Epóxido/metabolismo , Heptacloro Epóxido/toxicidade , Hipersensibilidade Tardia/induzido quimicamente , Imunoglobulina G/análise , Imunoglobulina G/sangue , Imunoglobulina M/análise , Imunoglobulina M/sangue , Inseticidas/toxicidade , Células Matadoras Naturais/efeitos dos fármacos , Tamanho da Ninhada de Vivíparos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Linhagem , Gravidez , Ratos , Ratos Sprague-Dawley , Baço/efeitos dos fármacos , Subpopulações de Linfócitos T/efeitos dos fármacos , Distribuição Tecidual
18.
Food Addit Contam ; 13(2): 231-5, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9064248

RESUMO

This monitoring study of 192 samples of cow's milk collected from the central region of Veracruz state was conducted to determine the contamination levels of organochlorine pesticides. The results obtained for mean DDT and HCH levels were 0.057 and 0.098 mg/kg respectively expressed on fat basis and are within FAO tolerances and similar to those found in other tropical countries.


Assuntos
Inseticidas/análise , Leite/química , Resíduos de Praguicidas/análise , Aldrina/análise , Aldrina/metabolismo , Animais , Bovinos , Cromatografia Gasosa , DDT/análise , DDT/metabolismo , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/metabolismo , Análise de Alimentos , Contaminação de Alimentos , Guias como Assunto , Heptacloro/análise , Heptacloro/metabolismo , Heptacloro Epóxido/análise , Heptacloro Epóxido/metabolismo , Hexaclorocicloexano/análise , Hexaclorocicloexano/metabolismo , Inseticidas/metabolismo , México , Resíduos de Praguicidas/metabolismo , Organização Mundial da Saúde
20.
J Environ Sci Health B ; 27(6): 711-28, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1460243

RESUMO

Field trials were conducted to measure translocation of pesticides by summer and winter forage/pasture species from soil containing aged residues of heptachlor and, to a lesser extent, dieldrin. Substantial amounts of heptachlor epoxide, and lesser amounts of gamma-chlordane were translocated to plants from contaminated soil. Residue levels varied with crop species and stage of plant development. In summer crops residues were higher in soybean > cowpeas > lab-lab > Sorghum > millet > sweet saccaline at the grazing and mature stages. Compared to glasshouse studies undertaken previously, residues in crops grown under field conditions were much lower. This apparently reflects the lower soil moisture levels and the reduced rates of translocation. Heptachlor residues in winter crops were highest in Saia oats > Berseem clover > Haifa clover > Cassia oats > Tetila ryegrass > Schooner barley > Shaftal clover > Hunter river lucerne at the grazing stage. There were no detectable levels in barley and oats at the mature stage. No dieldrin residues were translocated into the various crop species.


Assuntos
Animais Domésticos , Inseticidas/metabolismo , Resíduos de Praguicidas/metabolismo , Plantas/metabolismo , Poluentes do Solo/metabolismo , Ração Animal , Animais , Clordano/metabolismo , Dieldrin/metabolismo , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Fabaceae/crescimento & desenvolvimento , Fabaceae/metabolismo , Contaminação de Alimentos , Heptacloro/metabolismo , Heptacloro Epóxido/metabolismo , Desenvolvimento Vegetal , Plantas Medicinais , Poaceae/crescimento & desenvolvimento , Poaceae/metabolismo
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