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1.
Chemosphere ; 138: 60-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26037817

RESUMO

The Great Pacific Garbage Patch (GPGP) is a gyre of marine plastic debris in the North Pacific Ocean, and nearby is Midway Atoll which is a focal point for ecological damage. This study investigated 13 C4-C16 perfluorinated carboxylic acids (PFCAs), four (C4, C6, C8 and C10) perfluorinated sulfonates and perfluoro-4-ethylcyclohexane sulfonate [collectively perfluoroalkyl acids (PFAAs)] in black-footed albatross tissues (collected in 2011) from Midway Atoll. Of the 18 PFCAs and PFSAs monitored, most were detectable in the liver, muscle and adipose tissues. The concentrations of PFCAs and PFSAs were higher than those in most seabirds from the arctic environment, but lower than those in most of fish-eating water birds collected in the U.S. mainland. The concentrations of the PFAAs in the albatross livers were 7-fold higher than those in Laysan albatross liver samples from the same location reported in 1994. The concentration ranges of PFOS were 22.91-70.48, 3.01-6.59 and 0.53-8.35 ng g(-1) wet weight (ww), respectively, in the liver, muscle and adipose. In the liver samples PFOS was dominant, followed by longer chain PFUdA (8.04-18.70 ng g(-1) ww), PFTrDA, and then PFNA, PFDA and PFDoA. Short chain PFBA, PFPeA, PFBS and PFODA were below limit of quantification. C8-C13 PFCAs showed much higher composition compared to those found in other wildlife where PFOS typically predominated. The concentrations of PFUdA in all 8 individual albatross muscle samples were even higher than those of PFOS. This phenomenon may be attributable to GPGP as a pollution source as well as PFAA physicochemical properties.


Assuntos
Alcanossulfonatos/análise , Aves/metabolismo , Ácidos Carboxílicos/análise , Monitoramento Ambiental/métodos , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Tecido Adiposo/metabolismo , Alcanossulfonatos/farmacocinética , Animais , Ácidos Carboxílicos/farmacocinética , Peixes/metabolismo , Fluorocarbonos/farmacocinética , Havaí , Fígado/metabolismo , Músculos/metabolismo , Oceano Pacífico , Plásticos/química , Distribuição Tecidual , Poluentes Químicos da Água/farmacocinética
2.
PLoS One ; 10(4): e0123041, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25901941

RESUMO

Polychlorinated biphenyls (PCBs) are ubiquitous in the environment. Midway Atoll, located in the North Pacific Ocean, was occupied by the military during and after World War II. However, Midway Atoll has become a national wildlife refuge and home to many different seabirds today, including the black-footed albatross (Diomedea nigripes) (BFAL). The profiles and toxic equivalents (TEQ) of PCB congeners in the plasma and preen oil of BFAL chicks and adults were determined in this study. The concentrations of the total PCBs in the plasma samples of chicks and adults collected in Midway Atoll ranged from 2.3 to 223.8 (mean 80.1) and 22.8 to 504.5 (mean 158.6) ng g(-1) (wet weight, ww), respectively. The TEQs ranged from 0.2 to 0.6 (mean 0.4) and 0.4 to 1.6 (mean 0.9) pg g(-1) ww, respectively, in the plasma samples of chicks and adults from Midway Atoll. The major congeners in the plasma samples of chicks and adults included PCBs 31, 87, 97, 99, 118, 138, 153, and 180, accounting for 70% of the total PCBs. The concentrations of the total PCBs in the adult preen oil samples ranged from 1693 to 39404 (mean 10122) ng g(-1) (ww), of which 97% were PCBs 105, 118, 128, 138, 153, 161, 172, and 183.


Assuntos
Aves/sangue , Monitoramento Ambiental , Óleos/química , Bifenilos Policlorados/sangue , Poluentes Químicos da Água/sangue , Fatores Etários , Animais , Ecotoxicologia , Oceano Pacífico , Bifenilos Policlorados/toxicidade , Poluentes Químicos da Água/toxicidade
3.
PLoS One ; 9(1): e86441, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24466100

RESUMO

This study was designed to determine concentrations of polycyclic aromatic hydrocarbons (PAHs) in soil samples collected from Midway Atoll and evaluate their potential risks to human health. The total concentrations of 16 PAHs ranged from 3.55 to 3200 µg kg(-1) with a mean concentration of 198 µg kg(-1). Higher molecular weight PAHs (4-6 ring PAHs) dominated the PAH profiles, accounting for 83.3% of total PAH mass. PAH diagnostic ratio analysis indicated that primary sources of PAHs in Midway Atoll could be combustion. The benzo[a]pyrene equivalent concentration (BaPeq) in most of the study area (86.5%) was less than 40 µg kg(-1) BaPeq and total incremental lifetime cancer risks of PAHs ranged from 1.00×10(-10) to 9.20×10(-6) with a median value of 1.24×10(-7), indicating a minor carcinogenic risk of PAHs in Midway Atoll.


Assuntos
Carcinógenos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Poluentes do Solo/química , Solo/química , Carcinógenos/toxicidade , Havaí , Humanos , Neoplasias/induzido quimicamente , Oceano Pacífico , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco , Poluentes do Solo/toxicidade
4.
PLoS One ; 8(8): e71521, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23951182

RESUMO

Concentrations of 28 polychlorinated biphenyls (PCBs) were assessed in soils from the Midway Atoll in the central North Pacific Ocean. The analytical procedure involved the application of accelerated solvent extraction (ASE) and gas chromatography coupled with ion trap mass spectrometric detection (GC/ITMS) for identification and quantification. Among the 28 PCB congeners studied, 26 of them, except CB195 and CB209, were detected in the analyzed samples at different frequencies. The total concentrations of 28 indicator PCBs (ΣPCBs) ranged from 2.6 to 148.8 ng g⁻¹ with an average value of 50.7 ng g⁻¹ and median of 39.5 ng g⁻¹. Sources and congeners' pattern of PCB were investigated in the soil of Midway Atoll. The principal component analysis indicated that the compositions of PCBs in most of the soil samples were similar. The total concentrations of PCBs were used to assess the cancer risk probabilities in humans via ingestion, dermal contact and inhalation of soil particles. Very low cancer risk was found in all soil samples caused by ΣPCBs.


Assuntos
Monitoramento Ambiental , Bifenilos Policlorados/análise , Poluentes do Solo/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Neoplasias/induzido quimicamente , Oceano Pacífico , Bifenilos Policlorados/efeitos adversos , Medição de Risco , Solo/química , Poluentes do Solo/efeitos adversos
5.
Sci Total Environ ; 452-453: 421-6, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23542436

RESUMO

Concentrations of legacy organochlorine pesticides (OCPs), including dichlorodiphenyltrichloroethane (DDT) and its metabolites (e.g., DDE and DDD), and hexachlorocyclohexanes (HCHs) were determined in 111 soil samples from the Midway Atoll. OCPs were found in all samples analyzed, with predominance of α-HCH, p,p'-DDD and p,p'-DDT. The total concentrations ranged from 0 to 127 ng g(-1) with a median concentration of 17 ng g(-1) for HCHs and 1.4 to 643 ng g(-1) with a median concentration of 168 ng g(-1) for DDTs. The possible degradation pathways and potential sources of DDTs and HCHs were investigated. The total concentrations of DDTs and HCHs were used to evaluate the cancer risk probabilities in humans via ingestion, dermal contact and inhalation of soil particles. Very low cancer risk was found in all soil samples caused by ΣDDTs and ΣHCHs.


Assuntos
Neoplasias/etiologia , Praguicidas/análise , Praguicidas/toxicidade , Poluentes do Solo/análise , DDT/análise , Diclorodifenil Dicloroetileno/análise , Diclorodifenildicloroetano/análise , Hexaclorocicloexano/análise , Humanos , Hidrocarbonetos Clorados/análise , Neoplasias/induzido quimicamente , Medição de Risco , Estados Unidos
6.
Chemosphere ; 84(7): 1002-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21616519

RESUMO

Several nuclear tests were performed at Enewetak and Bikini Atolls in the Marshall Islands between 1946 and 1958. The events at Bikini Atoll involved several ships that were tested for durability during nuclear explosions, and 24 vessels now rest on the bottom of the Bikini lagoon. Nine soil samples were collected from different areas on the two islands of the atoll, and eighteen sediment, nine fish, and one lobster were collected in the vicinity of the sunken ships. Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polychlorinated terphenyls (PCTs) in these samples were analyzed using gas chromatography/ion trap mass spectrometry (GC/ITMS). The average recoveries ranged from 78% to 104% for the different PCB congeners. The limits of detection (LOD) for PCBs, PCTs, DDE, DDT, and dieldrin ranged 10-50 pg g(-1). Some fish from Enewetak contained PCBs at a concentration range of 37-137 ng g(-1), dry weight (dw), and most of the soils from Enewetak showed evidence of PCBs (22-392 ng g(-1)dw). Most of the Bikini lagoon sediment samples contained PCBs, and the highest was the one collected from around the Saratoga, an aircraft carrier (1555 ng g(-1)dw). Some of the fish samples, most of the soil samples, and only one of the sediment samples contained 2,2-bis(4-chlorophenyl)-1,1-dichloroethylene (DDE) and PCBs. In addition to PCBs, the soils from Enewetak Atoll contained PCTs. PCTs were not detected in the sediment samples from Bikini Atoll. The results suggest local pollution sources of PCBs, PCTs, and OCPs.


Assuntos
Poluentes Ambientais/análise , Peixes/metabolismo , Sedimentos Geológicos/química , Hidrocarbonetos Clorados/análise , Solo/química , Animais , DDT/análise , DDT/metabolismo , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Poluição Ambiental/estatística & dados numéricos , Hidrocarbonetos Clorados/metabolismo , Limite de Detecção , Micronésia , Praguicidas/análise , Praguicidas/metabolismo , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo
7.
Sci Total Environ ; 322(1-3): 81-93, 2004 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-15081740

RESUMO

The Hawaiian monk seal (Monachus schauinslandi) is an endangered species found only in the Hawaiian Island chain. The largest subpopulation, at French Frigate Shoals, has been in decline since 1989. In order to assess organochlorine (OC) levels in the Hawaiian monk seals, whole blood and blubber samples were collected in 1999 from 46 free-ranging Hawaiian monk seals at French Frigate Shoals, and were analyzed for eight dioxin-like polychlorinated biphenyls (PCBs) as well as six other PCB congeners, DDT and DDT metabolites. Average levels of the total PCBs in blood samples from adult male, juvenile and reproductive female groups were 4800, 4000 and 3000 ng/g lipid wt., respectively, whereas 3200, 1300 and 1200 ng/g, respectively, in blubber from the three corresponding groups. p,p'-DDE was the only DDT detected in blubber samples, and no DDTs were detected in blood samples. Concentrations of the total PCBs in adult males were significantly higher than the levels measured in either reproductive females or juveniles. There were significant correlations between age and blubber p,p'-DDE, estimated mass and total blood PCBs or blubber p,p'-DDE, and body condition and total blood PCBs. Although it is clear that the Hawaiian monk seal has been exposed to OCs, it is unclear what biological effects, if any, these xenobiotics may have on the animals.


Assuntos
Poluentes Ambientais/sangue , Inseticidas/sangue , Bifenilos Policlorados/sangue , Estações do Ano , Tecido Adiposo/química , Animais , Poluentes Ambientais/análise , Feminino , Inseticidas/análise , Masculino , Oceano Pacífico , Focas Verdadeiras/sangue , Distribuição Tecidual
8.
Chemosphere ; 54(8): 1155-61, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14664844

RESUMO

Marine sand and seawater samples were collected in March 2002 from Laysan Island in the Hawaiian Islands National Wildlife Refuge, where a small area was contaminated by the carbamate insecticide carbofuran. Carbofuran was still detected at microg g(-1) levels in the Laysan sand after its identification in 1998 and initial observation of the toxicity in 1988. The persistence of carbofuran in the marine sand was investigated in the dark in a 30 degrees C oven, and in distilled deionized water and seawater samples exposed to artificial 300 nm light and to direct sunlight. The laboratory study showed a half-life (t1/2) of approximately 40 days for carbofuran in the native sand and in Ottawa sand. The photolysis of carbofuran was faster in seawater than in distilled deionized water when it was exposed to 300 nm light (t1/2, 0.1 vs. 3.1 h) and to direct sunlight (t1/2, 7.5 vs. 41.6 h). The large difference between the laboratory results and the field observation of carbofuran dissipation suggests that carbofuran degradation at the remote, undisturbed marine site may be governed by its unique environmental factors.


Assuntos
Carbofurano/química , Sedimentos Geológicos/química , Água do Mar/química , Carbofurano/análise , Estabilidade de Medicamentos , Sedimentos Geológicos/análise , Meia-Vida , Fotólise , Água do Mar/análise , Luz Solar , Temperatura , Raios Ultravioleta , Água/química
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