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1.
Bull Environ Contam Toxicol ; 101(2): 294, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29971608

RESUMO

The original version of this article contained a mistake. Author name in the text citation and reference in section should be Maldonado et al (2016), it was incorrectly spelled as Maldinado et al (2015).

2.
Bull Environ Contam Toxicol ; 100(6): 741-747, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29796875

RESUMO

Northern Cardinal eggs from six neighborhoods near Washington DC were analyzed for organochlorine pesticides and PCBs. All compounds were detected more frequently and at higher concentrations in more heavily urbanized neighborhoods. DDT (mostly as p,p'-DDE) was detected in all neighborhoods. p,p'-DDT was typically 0.5‒16 ng/g (ww) in most suburban neighborhoods but was not detected (< 0.1 ng/g) in more rural areas; however, p,p'-DDT was 127‒1130 ng/g in eggs from two suburban Maryland nests and comprised 65.7% of total p,p'-DDT isomers in the most contaminated sample, indicating recent exposure to un-weathered DDT. Total chlordane (sum of 5 compounds) was 2‒70 ng/g; concentrations were greatest in older suburban neighborhoods. Total PCB (sum of detected congeners) was < 5‒21 ng/g. Congener patterns were similar in all neighborhoods and resembled those typical of weathered mixtures. Results indicate that wildlife remains exposed to low concentrations of legacy contaminants in suburban neighborhoods and that cardinal eggs can be used to monitor localized contamination.


Assuntos
Ovos/análise , Poluentes Ambientais/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Animais , Aves , DDT/análise , Diclorodifenil Dicloroetileno/análise , District of Columbia , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise
3.
Mar Pollut Bull ; 115(1-2): 525-533, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28012734

RESUMO

Surface water, sediment, and fish from Biscayne Bay, coastal wetlands adjacent to the Bay, and canals discharging into the Bay were sampled for determination of baseline contamination in Biscayne National Park. While the number of contaminants detected in canal waters was greater during the wet season than the dry season, no seasonal difference was evident for Biscayne Bay or coastal wetland waters. Estrogen equivalency (as 17ß-estradiol equivalents), as predicted by the Yeast Estrogen Screen, for extracts of passive water samplers deployed in canals and wetlands was elevated during the wet relative to the dry season. Generally, contamination in water, sediments, and fish was greater in the canals than in Biscayne Bay and the wetlands. Guideline levels for sediment contaminant were exceeded most frequently in canals relative to the coastal wetlands and the Bay. Further investigation is necessary to better understand the impact of contaminants in Biscayne National Park.


Assuntos
Monitoramento Ambiental , Estrogênios/análise , Peixes/fisiologia , Poluentes Químicos da Água/análise , Animais , Florida , Sedimentos Geológicos , Parques Recreativos , Estações do Ano , Áreas Alagadas
4.
Fish Physiol Biochem ; 39(5): 1115-28, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23334565

RESUMO

Little is known about the effects of brominated flame retardants in teleosts and some of the information currently available is inconsistent. This study examined effects of dietary exposure to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) on thyroid condition, body mass and size, and gonadal development of zebrafish. Pubertal, 49-day-old (posthatch) fish were fed diets without BDE-47 (control) or with 1, 5 or 25 µg/g BDE-47/diet. Treatments were conducted in triplicate 30-L tanks each containing 50 zebrafish, and 15 fish per treatment (5 per tank) were sampled at days 40, 80 and 120 of exposure. Measurements were taken of body mass, standard length, head depth and head length. Sex (at 40-120 days of exposure), germ cell stage (at 40 days) and thyroid condition (at 120 days; follicular cell height, colloid depletion, angiogenesis) were histologically determined. Whole-body BDE-47 levels at study completion were within the high end of levels reported in environmentally exposed (wild) fishes. Analysis of variance was used to determine differences among treatments at each sampling time. No effects were observed on thyroid condition or germ cell stage in either sex. Reduced head length was observed in females exposed to BDE-47 at 80 days but not at 40 or 120 days. In males, no apparent effects of BDE-47 were observed at 40 and 80 days, but fish exposed to 25 µg/g had lower body mass at 120 days compared to control fish. These observations suggest that BDE-47 at environmentally relevant whole-body concentrations does not affect thyroid condition or pubertal development of zebrafish but does affect growth during the juvenile-to-adult transition, especially in males.


Assuntos
Retardadores de Chama/toxicidade , Gônadas/efeitos dos fármacos , Éteres Difenil Halogenados/toxicidade , Hidrocarbonetos Bromados/toxicidade , Glândula Tireoide/efeitos dos fármacos , Peixe-Zebra/crescimento & desenvolvimento , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Gônadas/crescimento & desenvolvimento , Éteres Difenil Halogenados/administração & dosagem , Masculino , Glândula Tireoide/fisiologia , Fatores de Tempo
5.
Chemosphere ; 90(1): 20-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22939514

RESUMO

Polybrominated diphenyl ethers (PBDEs) were determined in fish collected from the Gila River, Arizona, a tributary of the Colorado River in the lower part of the Colorado River Basin. Fish samples were collected at sites on the Gila River downstream from Hayden, Phoenix, and Arlington, Arizona in late summer 2003. The Gila River is ephemeral upstream of the Phoenix urban area due to dams and irrigation projects and has limited perennial flow downstream of Phoenix due to wastewater and irrigation return flows. Fifty PBDE congeners were analyzed by high resolution gas chromatography/high resolution mass spectrometry using labeled surrogate standards in composite samples of male and female common carp (Cyrpinus carpio), largemouth bass (Micropterus salmoides) and channel catfish (Ictalurus punctatus). The predominant PBDE congeners detected and quantified were 47, 100, 153, 49, 28, and 17. Concentrations of total PBDEs in these fish ranged from 1.4 to 12700 ng g(-1) wet weight, which are some of the highest concentrations reported in fish from the United States. Differences in metabolism of several PBDE congeners by carp is clear at the Phoenix site; congeners with at least one ring of 2,4,5-substitution are preferentially metabolized as are congeners with 2,3,4-substitution.


Assuntos
Monitoramento Ambiental , Peixes/metabolismo , Éteres Difenil Halogenados/metabolismo , Rios/química , Poluentes Químicos da Água/metabolismo , Animais , Arizona , Feminino , Éteres Difenil Halogenados/análise , Masculino , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos
6.
Environ Toxicol Chem ; 32(3): 548-61, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23212976

RESUMO

Previous studies have shown inexplicable declines in breeding waterbirds within western New York/New Jersey Harbor between 1996 and 2002 and elevated polychlorinated dibenzo-p-dioxins and polychlorinated biphenyls (PCBs) in double-crested cormorant (Phalacrocorax auritus) eggs. The present study assessed associations between immune function, prefledgling survival, and selected organochlorine compounds and metals in herring gulls (Larus argentatus) and black-crowned night herons (Nycticorax nycticorax) in lower New York Harbor during 2003. In pipping gull embryos, lymphoid cells were counted in the thymus and bursa of Fabricius (sites of T and B lymphocyte maturation, respectively). The phytohemagglutinin (PHA) skin response assessed T cell function in gull and heron chicks. Lymphocyte proliferation was measured in vitro in adult and prefledgling gulls. Reference data came from the Great Lakes and Bay of Fundy. Survival of prefledgling gulls was poor, with only 0.68 and 0.5 chicks per nest surviving to three and four weeks after hatch, respectively. Developing lymphoid cells were reduced 51% in the thymus and 42% in the bursa of gull embryos from New York Harbor. In vitro lymphocyte assays demonstrated reduced spontaneous proliferation, reduced T cell mitogen-induced proliferation, and increased B cell mitogen-induced proliferation in gull chicks from New York Harbor. The PHA skin response was suppressed 70 to 80% in gull and heron chicks. Strong negative correlations (r = -0.95 to -0.98) between the PHA response and dioxins and PCBs in gull livers was strong evidence suggesting that these chemicals contribute significantly to immunosuppression in New York Harbor waterbirds.


Assuntos
Aves/fisiologia , Hidrocarbonetos Clorados/metabolismo , Metais/metabolismo , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo , Animais , Aves/imunologia , Charadriiformes/imunologia , Charadriiformes/fisiologia , Monitoramento Ambiental , Estuários , Hidrocarbonetos Clorados/toxicidade , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/fisiologia , Metais/toxicidade , New York , Óvulo/metabolismo , Saúde Reprodutiva/estatística & dados numéricos , Poluentes Químicos da Água/toxicidade
7.
Arch Environ Contam Toxicol ; 55(2): 161-72, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18202883

RESUMO

The lower Missouri River was studied to determine the distribution of selected persistent organic pollutants and bioavailable metals in depositional sediments. Nineteen sites between Omaha, Nebraska and Jefferson City, Missouri were sampled. This stretch of the river receives point-source and non-point-source inputs from industrial, urban, and agricultural activities. As part of an ecological assessment of the river, concentrations of 29 legacy organochlorine pesticides (OC pesticides), including chlordanes, DDTs, and hexachlorocyclohexanes; a select list of current-use pesticides, including trifluralin, diazinon, chlorpyrifos, and permethrin, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), divalent metals (copper, nickel, zinc, cadmium, and lead), and polybrominated diphenyl ethers (PBDEs) were determined. Concentrations (dry weight basis) of OC pesticides in the sediments were less than 1 ng/g, with the exception of the backwater sediment collected from the mouth of the Blue River in the Kansas City metropolitan area, which contained up to 20 ng/g total chlordane, 8.1 ng/g p,p'-DDE, 1.5 ng/g lindane, 4.8 ng/g dieldrin, and 3 ng/g endrin. Concentrations of chlorpyrifos and permethrin ranged from less than 1 ng/g to 5.5 ng/g and 44 ng/g, respectively. Concentrations of PCBs ranged from less than 11 ng/g to 250 ng/g, with the Blue River and Sibley sediments containing 100 and 250 ng/g total PCBs, respectively. Concentrations of total PAHs at 17 of the 19 sites ranged from 250 to 700 ng/g, whereas the Riverfront and Blue River sites in Kansas City contained 1100 ng/g and nearly 4000 ng/g, respectively. Concentrations of the metals did not vary significantly among most sites; however, the Blue River site contained elevated concentrations of zinc (104 microg/g), cadmium (0.7 microg/g), and lead (34 microg/g) compared to the other sites. The moderately high concentrations of acid-volatile sulfide in the sediments suggest a low potential for metal toxicity to benthic organisms along this reach of the Missouri River. The depositional area sediments contained concentrations of the targeted persistent organic chemicals and metals that were below published probable effect level concentrations.


Assuntos
Sedimentos Geológicos/análise , Metais Pesados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios , Poluição Química da Água/análise , Disponibilidade Biológica , Cromatografia Gasosa , Bifenil Polibromatos/análise , Estados Unidos
8.
Environ Health Perspect ; 111(9): 1180-7, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12842771

RESUMO

Bisphenol A (BPA) is a monomer with estrogenic activity that is used in the production of food packaging, dental sealants, polycarbonate plastic, and many other products. The monomer has previously been reported to hydrolyze and leach from these products under high heat and alkaline conditions, and the amount of leaching increases as a function of use. We examined whether new and used polycarbonate animal cages passively release bioactive levels of BPA into water at room temperature and neutral pH. Purified water was incubated at room temperature in new polycarbonate and polysulfone cages and used (discolored) polycarbonate cages, as well as control (glass and used polypropylene) containers. The resulting water samples were characterized with gas chromatography/mass spectrometry (GC/MS) and tested for estrogenic activity using an MCF-7 human breast cancer cell proliferation assay. Significant estrogenic activity, identifiable as BPA by GC/MS (up to 310 micro g/L), was released from used polycarbonate animal cages. Detectable levels of BPA were released from new polycarbonate cages (up to 0.3 micro g/L) as well as new polysulfone cages (1.5 micro g/L), whereas no BPA was detected in water incubated in glass and used polypropylene cages. Finally, BPA exposure as a result of being housed in used polycarbonate cages produced a 16% increase in uterine weight in prepubertal female mice relative to females housed in used polypropylene cages, although the difference was not statistically significant. Our findings suggest that laboratory animals maintained in polycarbonate and polysulfone cages are exposed to BPA via leaching, with exposure reaching the highest levels in old cages.


Assuntos
Animais de Laboratório , Exposição Ambiental , Estrogênios não Esteroides/análise , Abrigo para Animais , Fenóis/análise , Animais , Compostos Benzidrílicos , Bioensaio , Neoplasias da Mama/patologia , Estrogênios não Esteroides/química , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Camundongos , Fenóis/química , Reprodutibilidade dos Testes , Solubilidade , Temperatura , Células Tumorais Cultivadas , Útero/anatomia & histologia , Água/química
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