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1.
Environ Monit Assess ; 186(10): 6471-91, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24934131

RESUMEN

Fishes were collected at 16 sites within the three major river drainages (Delaware, Susquehanna, and Ohio) of Pennsylvania. Three species were evaluated for biomarkers of estrogenic/antiandrogenic exposure, including plasma vitellogenin and testicular oocytes in male fishes. Smallmouth bass Micropterus dolomieu, white sucker Catostomus commersonii, and redhorse sucker Moxostoma species were collected in the summer, a period of low flow and low reproductive activity. Smallmouth bass were the only species in which testicular oocytes were observed; however, measurable concentrations of plasma vitellogenin were found in male bass and white sucker. The percentage of male bass with testicular oocytes ranged from 10 to 100%, with the highest prevalence and severity in bass collected in the Susquehanna drainage. The percentage of males with plasma vitellogenin ranged from 0 to 100% in both bass and sucker. Biological findings were compared with chemical analyses of discrete water samples collected at the time of fish collections. Estrone concentrations correlated with testicular oocytes prevalence and severity and with the percentage of male bass with vitellogenin. No correlations were noted with the percentage of male sucker with vitellogenin and water chemical concentrations. The prevalence and severity of testicular oocytes in bass also correlated with the percent of agricultural land use in the watershed above a site. Two sites within the Susquehanna drainage and one in the Delaware were immediately downstream of wastewater treatment plants to compare results with upstream fish. The percentage of male bass with testicular oocytes was not consistently higher downstream; however, severity did tend to increase downstream.


Asunto(s)
Monitoreo del Ambiente , Peces/fisiología , Contaminantes Químicos del Agua/análisis , Agricultura , Animales , Biomarcadores , Masculino , Pennsylvania , Reproducción , Ríos/química , Estaciones del Año , Vitelogeninas/sangre , Contaminantes Químicos del Agua/toxicidad
2.
Sci Total Environ ; 468-469: 530-43, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24055669

RESUMEN

Anthropogenic semivolatile organic compounds (SOCs) that persist in the environment, bioaccumulate, are toxic at low concentrations, and undergo long-range atmospheric transport (LRT) were identified and quantified in the atmosphere of a Saharan dust source region (Mali) and during Saharan dust incursions at downwind sites in the eastern Caribbean (U.S. Virgin Islands, Trinidad and Tobago) and Cape Verde. More organochlorine and organophosphate pesticides (OCPPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyl (PCB) congeners were detected in the Saharan dust region than at downwind sites. Seven of the 13 OCPPs detected occurred at all sites: chlordanes, chlorpyrifos, dacthal, dieldrin, endosulfans, hexachlorobenzene (HCB), and trifluralin. Total SOCs ranged from 1.9-126 ng/m(3) (mean = 25 ± 34) at source and 0.05-0.71 ng/m(3) (mean = 0.24 ± 0.18) at downwind sites during dust conditions. Most SOC concentrations were 1-3 orders of magnitude higher in source than downwind sites. A Saharan source was confirmed for sampled air masses at downwind sites based on dust particle elemental composition and rare earth ratios, atmospheric back trajectory models, and field observations. SOC concentrations were considerably below existing occupational and/or regulatory limits; however, few regulatory limits exist for these persistent organic compounds. Long-term effects of chronic exposure to low concentrations of SOCs are unknown, as are possible additive or synergistic effects of mixtures of SOCs, biologically active trace metals, and mineral dust particles transported together in Saharan dust air masses.


Asunto(s)
Movimientos del Aire , Contaminantes Atmosféricos/análisis , Polvo/análisis , Monitoreo del Ambiente/estadística & datos numéricos , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , África del Norte , Cabo Verde , Región del Caribe , Monitoreo del Ambiente/métodos , Geografía , Malí , Espectrometría de Masas , Análisis de Componente Principal , Espectrofotometría Atómica
3.
Water Res ; 47(10): 3347-63, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23623470

RESUMEN

Animal manures, used as a nitrogen source for crop production, are often associated with negative impacts on nutrient levels in surface water. The concentrations of estrogens in streams from these manures also are of concern due to potential endocrine disruption in aquatic species. Streams associated with livestock operations were sampled by discrete samples (n = 38) or by time-integrated polar organic chemical integrative samplers (POCIS, n = 19). Samples were analyzed for estrogens by gas chromatography-tandem mass spectrometry (GC-MS(2)) and estrogenic activity was assessed by three bioassays: Yeast Estrogen Screen (YES), T47D-KBluc Assay, MCF-7 Estrogenicity Screen (E-Screen). Samples were collected from 19 streams within small (≈ 1-30 km(2)) watersheds in 12 U.S. states representing a range of hydrogeologic conditions, dominated by: dairy (3), grazing beef (3), feedlot cattle (1); swine (5); poultry (3); and 4 areas where no livestock were raised or manure was applied. Water samples were consistently below the United Kingdom proposed Lowest Observable Effect Concentration for 17ß-estradiol in fish (10 ng/L) in all watersheds, regardless of land use. Estrogenic activity was often higher in samples during runoff conditions following a period of manure application. Estrone was the most commonly detected estrogen (13 of 38 water samples, mean 1.9, maximum 8.3 ng/L). Because of the T47D-KBluc assay's sensitivity towards estrone (1.4 times 17ß-estradiol) it was the most sensitive method for detecting estrogens, followed by the E-Screen, GC-MS(2), and YES. POCIS resulted in more frequent detections of estrogens than discrete water samples across all sites, even when applying the less-sensitive YES bioassay to the POCIS extracts.


Asunto(s)
Bioensayo/métodos , Disruptores Endocrinos/análisis , Estrógenos/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Agricultura , Animales , Bovinos , Estradiol/análisis , Receptor alfa de Estrógeno/genética , Estrógenos/química , Estrógenos/toxicidad , Estrona/análisis , Peces , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Ganado , Estiércol , Aves de Corral , Porcinos , Pruebas de Toxicidad/métodos , Estados Unidos , Levaduras/efectos de los fármacos
4.
Environ Sci Technol ; 46(10): 5336-43, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22540536

RESUMEN

Data were collected at a wastewater treatment plant (WWTP) in Burlington, Vermont, USA, (serving 30,000 people) to assess the relative contribution of CSO (combined sewer overflow) bypass flows and treated wastewater effluent to the load of steroid hormones and other wastewater micropollutants (WMPs) from a WWTP to a lake. Flow-weighted composite samples were collected over a 13 month period at this WWTP from CSO bypass flows or plant influent flows (n = 28) and treated effluent discharges (n = 22). Although CSO discharges represent 10% of the total annual water discharge (CSO plus treated plant effluent discharges) from the WWTP, CSO discharges contribute 40-90% of the annual load for hormones and WMPs with high (>90%) wastewater treatment removal efficiency. By contrast, compounds with low removal efficiencies (<90%) have less than 10% of annual load contributed by CSO discharges. Concentrations of estrogens, androgens, and WMPs generally are 10 times higher in CSO discharges compared to treated wastewater discharges. Compound concentrations in samples of CSO discharges generally decrease with increasing flow because of wastewater dilution by rainfall runoff. By contrast, concentrations of hormones and many WMPs in samples from treated discharges can increase with increasing flow due to decreasing removal efficiency.


Asunto(s)
Monitoreo del Ambiente , Hormonas/análisis , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos , Movimientos del Agua , Contaminantes Químicos del Agua/análisis , Vermont , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua
5.
Arch Environ Contam Toxicol ; 52(3): 294-305, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17285235

RESUMEN

Current-use pesticides (CUPs) and banned organochlorine compounds (OCCs) were measured in precipitation (snowpack and rain) and lake sediments from two national parks in the Western United States to determine their occurrence and distribution in high-elevation environments. CUPs frequently detected in snow were endosulfan, dacthal, and chlorothalonil in concentrations ranging from 0.07 to 2.4 ng/L. Of the OCCs, chlordane, hexachlorobenzene, and two polychlorinated biphenyl congeners were detected in only one snow sample each. Pesticides most frequently detected in rain were atrazine, carbaryl, and dacthal in concentrations from 3.0 to 95 ng/L. Estimated annual deposition rates in one of the parks were 8.4 microg/m2 for atrazine, 9.9 microg/m2 for carbaryl, and 2.6 microg/m2 for dacthal, of which >85% occurred during summer. p,p'-DDE and p,p'-DDD were the most frequently detected OCCs in surface sediments from lakes. However, concentrations were low (0.12 to 4.7 microg/kg) and below levels at which harmful effects for benthic organisms are likely to be observed. DDD and DDE concentrations in an age-dated sediment core suggest that atmospheric deposition of DDT and its degradates, and possibly other banned OCCs, to high-elevation areas have been decreasing since the 1970s. Dacthal and endosulfan sulfate were present in low concentrations (0.11 to 1.2 microg/kg) and were the only CUPs detected in surface sediments. Both pesticides were frequently detected in snow, confirming that some CUPs entering high-elevation aquatic environments through atmospheric deposition are accumulating in lake sediments and potentially in aquatic biota as well.


Asunto(s)
Sedimentos Geológicos/análisis , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Lluvia/química , Nieve/química , Altitud , Colorado , Endosulfano/análisis , Monitoreo del Ambiente , Agua Dulce , Montana , Nitrilos/análisis , Ácidos Ftálicos/análisis
6.
Rev. biol. trop ; 54(supl.3): 9-21, Dec. 2006. ilus, tab
Artículo en Inglés | LILACS, SaludCR | ID: lil-637567

RESUMEN

An international team of scientists from government agencies and universities in the United States, U.S. Virgin Islands (USVI), Trinidad & Tobago, the Republic of Cape Verde, and the Republic of Mali (West Africa) is working together to elucidate the role Saharan dust may play in the degradation of Caribbean ecosystems. The first step has been to identify and quantify the persistent organic pollutants (POPs), trace metals, and viable microorganisms in the atmosphere in dust source areas of West Africa, and in dust episodes at downwind sites in the eastern Atlantic (Cape Verde) and the Caribbean (USVI and Trinidad & Tobago). Preliminary findings show that air samples from Mali contain a greater number of pesticides, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) and in higher concentrations than the Caribbean sites. Overall, POP concentrations were similar in USVI and Trinidad samples. Trace metal concentrations were found to be similar to crustal composition with slight enrichment of lead in Mali. To date, hundreds of cultureable micro-organisms have been identified from Mali, Cape Verde, USVI, and Trinidad air samples. The sea fan pathogen, Aspergillus sydowii, has been identified in soil from Mali and in air samples from dust events in the Caribbean. We have shown that air samples from a dust-source region contain orders of magnitude more cultureable micro-organisms per volume than air samples from dust events in the Caribbean, which in turn contain 3-to 4-fold more cultureable microbes than during non-dust conditions. Rev. Biol. Trop. 54 (Suppl. 3): 9-21. Epub 2007 Jan. 15.


Un grupo internacional de agencias gubernamentales y universidades de los Estados Unidos, las Islas Vírgenes (EUA), Trinidad y Tobago, la República de Cabo Verde y la República de Mali (África Oeste), está trabajando en conjunto para elucidar el papel que el polvo del Sahara puede estar jugando en el deterioro de los ecosistemas caribeños. El primer paso ha sido identificar y cuantificar los Contaminantes Orgánicos Persistentes (POPs, por sus siglas en inglés), los metales traza y los microorganismos viables presentes en la atmósfera de las áreas fuente de polvo de África occidental y en áreas ubicadas en la dirección del viento, como el Atlántico este (Cabo Verde) y el Caribe (IVEUA y Trinidad y Tobago), durante los episodios de transporte de polvo. Resultados preliminares indican que las muestras de aire de Mali contienen mayor número y mayores concentraciones de pesticidas, bifenilos policlorinados (PCBs) e hidrocarburos policíclicos aromáticos (PAHs) que las de los sitios del Caribe. Las concentraciones de POPs fueron similares en las muestras de USVI y de Trinidad. Se encontró que las concentraciones de metales traza fueron similares a las de la composición de la corteza, con un ligero enriquecimiento de plomo en Mali. Hasta la fecha, cientos de microorganismos cultivables han sido identificados en las muestras de Mali, Cabo Verde, IVEUA y Trinidad. Hallamos el patógeno de los abanicos de mar, Aspergillus sydowi, en las muestras de aire de Mali y en las muestras del Caribe durante polvaredas. Hemos demostrado que las muestras de aire provenientes de una región fuente de polvo, contienen más microorganismos cultivables por volumen -en órdenes de magnitud- que las muestras de aire tomadas en polvaredas en el Caribe, las cuales a su vez contienen tres a cuatro veces más microorganismos cultivables que aquellas tomadas cuando no hay polvaredas.


Asunto(s)
Contaminantes Orgánicos , África del Sur del Sahara , Desierto , África del Norte , Polvo , Contaminantes Ambientales
7.
Environ Sci Technol ; 35(12): 2448-54, 2001 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11432547

RESUMEN

The enantiomeric composition of polychlorinated biphenyl (PCB) atropisomers was measured in river and riparian biota (fish, bivalves, crayfish, water snakes, barn swallows) from selected sites throughout the United States by using chiral gas chromatography/mass spectrometry. Nonracemic enantiomeric fractions (EFs) were observed for PCBs 91, 95, 136, and 149 for aquatic and riparian biota from Lake Hartwell, SC, a reservoir heavily contaminated with PCBs, and for these congeners and PCBs 132, 174, 176, and 183 in river fish and bivalves nationwide. Fish and bivalves showed marked differences in EFs as compared to sedimentfound atthe same sampling sites, thus suggesting that PCBs are bioprocessed in biota in a different manner from those found in sediment (e.g., reductive dechlorination). Species-dependent patterns in PCB EFs were observed, which suggest differences in the ability of different species to bioprocess PCBs enantioselectively, most likely by metabolism. The presence of nonracemic PCBs in fish and bivalves suggests greater metabolic degradation of PCBs in these organisms than indicated from previous achiral studies and underscores the powerful potential of chiral analysis as a tracer of environmental bioprocesses.


Asunto(s)
Contaminantes Ambientales/análisis , Cadena Alimentaria , Bifenilos Policlorados/análisis , Contaminantes Químicos del Agua/análisis , Animales , Astacoidea , Disponibilidad Biológica , Ecosistema , Monitoreo del Ambiente , Contaminantes Ambientales/farmacocinética , Peces , Isomerismo , Moluscos , Bifenilos Policlorados/farmacocinética , Serpientes , Pájaros Cantores , Distribución Tisular , Contaminantes Químicos del Agua/farmacocinética
8.
Environ Sci Technol ; 35(1): 33-9, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11352023

RESUMEN

Enantiomeric ratios (ERs) for eight polychlorinated biphenyl (PCB) atropisomers were measured in aquatic sediment from selected sites throughout the United States by using chiral gas chromatography/mass spectrometry. Nonracemic ERs for PCBs 91, 95, 132, 136, 149, 174, and 176 were found in sediment cores from Lake Hartwell, SC, which confirmed previous inconclusive reports of reductive dechlorination of PCBs at these sites on the basis of achiral measurements. Nonracemic ERs for many of the atropisomers were also found in bed-sediment samples from the Hudson and Housatonic Rivers, thus indicating that some of the PCB biotransformation processes identified at these sites are enantioselective. Patterns in ERs among congeners were consistent with known reductive dechlorination patterns at both river sediment basins. The enantioselectivity of PCB 91 is reversed between the Hudson and Housatonic River sites, which implies that the two sites have different PCB biotransformation processes with different enantiomer preferences.


Asunto(s)
Sedimentos Geológicos/análisis , Bifenilos Policlorados/análisis , Bifenilos Policlorados/química , Biotransformación , Agua Dulce/análisis , Agua Dulce/química , Cromatografía de Gases y Espectrometría de Masas , Bifenilos Policlorados/metabolismo , Estereoisomerismo , Estados Unidos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo
9.
Sci Total Environ ; 248(2-3): 201-12, 2000 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-10805240

RESUMEN

Weekly composite rainfall samples were collected in three paired urban and agricultural regions of the Midwestern United States and along the Mississippi River during April-September 1995. The paired sampling sites were located in Mississippi, Iowa, and Minnesota. A background site, removed from dense urban and agriculture areas, was located near Lake Superior in Michigan. Herbicides were the predominant type of pesticide detected at every site. Each sample was analyzed for 47 compounds and 23 of 26 herbicides, 13 of 18 insecticides, and three of three related transformation products were detected in one or more sample from each paired site. The detection frequency of herbicides and insecticides were nearly equivalent at the paired Iowa and Minnesota sites. In Mississippi, herbicides were detected more frequently at the agricultural site and insecticides were detected more frequently at the urban site. The highest total wet depositional amounts (microg pesticide/m2 per season) occurred at the agricultural sites in Mississippi (1980 microg/m2) and Iowa (490 microg/m2) and at the urban site in Iowa (696 microg/m2). Herbicides accounted for the majority of the wet depositional loading at the Iowa and Minnesota sites, but methyl parathion (1740 microg/m2) was the dominant compound contributing to the total loading at the agricultural site in Mississippi. Atrazine, CIAT (a transformation product of atrazine and propazine) and dacthal were detected most frequently (76, 53, and 53%, respectively) at the background site indicating their propensity for long-range atmospheric transport.


Asunto(s)
Contaminantes Atmosféricos/análisis , Plaguicidas/análisis , Lluvia , Precipitación Química , Técnicas de Química Analítica/métodos , Ciudades , Herbicidas/análisis , Insecticidas/análisis , Iowa , Minnesota , Mississippi , Estaciones del Año
10.
Sci Total Environ ; 248(2-3): 213-26, 2000 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-10805241

RESUMEN

Weekly composite air samples were collected from early April through to mid-September 1995 at three paired urban and agricultural sites along the Mississippi River region of the Midwestern United States. The paired sampling sites were located in Mississippi, Iowa, and Minnesota. A background site, removed from dense urban and agricultural areas, was located on the shore of Lake Superior in Michigan. Each sample was analyzed for 49 compounds; of these, 21 of 26 herbicides, 13 of 19 insecticides, and 4 of 4 related transformation products were detected during the study, with most pesticides detected in more than one sample. The maximum number of pesticides detected in an air sample was 18. Herbicides were the predominant type of pesticide detected at every site. Detection frequencies of most herbicides were similar at the urban and agricultural sites in Iowa and Minnesota. In Mississippi, herbicides generally were detected more frequently at the agricultural site. The insecticides chlorpyrifos, diazinon, and carbaryl, which are used in agricultural and non-agricultural settings, were detected more frequently in urban sites than agricultural sites in Mississippi and Iowa. Methyl parathion was detected in 70% of the samples from the Mississippi agricultural site and at the highest concentration (62 ng/m3 air) of any insecticide measured in the study. At the background site, dacthal (100%), atrazine (35%), cyanazine (22%), and the (primarily atrazine) triazine transformation products CIAT (35%) and CEAT (17%) were detected most frequently, suggesting their potential for long-range atmospheric transport.


Asunto(s)
Contaminantes Atmosféricos/análisis , Plaguicidas/análisis , Agricultura , Precipitación Química , Ciudades , Monitoreo del Ambiente/métodos , Herbicidas/análisis , Insecticidas/análisis , Medio Oeste de Estados Unidos , Mississippi , Estaciones del Año
11.
Sci Total Environ ; 248(2-3): 227-40, 2000 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-10805242

RESUMEN

In April 1995, the US Geological Survey began a study to determine the occurrence and temporal distribution of 49 pesticides and pesticide metabolites in air and rain samples from an urban and an agricultural sampling site in Mississippi. The study was a joint effort between the National Water-Quality Assessment and the Toxic Substances Programs and was part of a larger study examining the occurrence and temporal distribution of pesticides in air and rain in the Mississippi River basin. Concurrent high-volume air and wet-only deposition samples were collected weekly. The air samplers consisted of a glass-fiber filter to collect particles and tandem polyurethane foam plugs to collect gas-phase pesticides. Every rain and air sample collected from the urban and agricultural sites had detectable levels of multiple pesticides. The magnitude of the total concentration was 5-10 times higher at the agricultural site as compared to the urban site. The pesticide with the highest concentration in rain at both sites was methyl parathion. The pesticide with the highest concentration in the air samples from the agricultural site was also methyl parathion, but from the urban site the highest concentration was diazinon followed closely by chlorpyrifos. More than two decades since p,p'-DDT was banned from use in the United States, p,p'-DDE, a metabolite of p,p'-DDT, was detected in every air sample collected from the agricultural site and in more than half of the air samples from the urban site.


Asunto(s)
Contaminantes Atmosféricos/análisis , Plaguicidas/análisis , Lluvia , Contaminantes Químicos del Agua/análisis , Agricultura , Ciudades , Mississippi
13.
Appl Opt ; 7(6): 1053-9, 1968 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20068739

RESUMEN

This paper presents measurements of astigmatism for a typical Czerny-Turner spectrograph and shows two ways of correcting astigmatism in this instrument by using lenses. For an f/6.3 instrument having a 0.75-m focal length collimating and camera mirror, the meridional and sagittal focal planes were separated approximately 15 mm at 60 mm left of the center of the film plane and approximately 43 mm at 70 mm to the right of the center of the plane, when the grating was set to put 5000 A in the center of the film plane. Measurements of astigmatism for different lines of the Hg spectrum with 5000 A in the center of the film plane showed the astigmatism to be determined primarily, if not entirely, by the angle at which the radiation left the grating and collimating mirror. The experimental results compared favorably with the theory given by Rosendahl. Two methods of correcting astigmatism by lenses were investigated: one experimental, the other theoretical. Both appear to be practical.

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