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1.
Water Environ Res ; 87(10): 1718-816, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26420104

RESUMO

This review covers selected 2014 articles on the biological effects of pollutants and human physical disturbances on marine and estuarine plants, animals, ecosystems and habitats. The review, based largely on journal articles, covers field and laboratory measurement activities (bioaccumulation of contaminants, field assessment surveys, toxicity testing and biomarkers) as well as pollution issues of current interest including endocrine disrupters, emerging contaminants, wastewater discharges, dredging and disposal, etc. Special emphasis is placed on effects of oil spills and marine debris due in part to the 2010 Deepwater Horizon oil blowout in the Gulf of Mexico and the 2011 Japanese tsunami. Several topical areas reviewed in the past (ballast water and ocean acidification) were dropped this year. The focus of this review is on effects, not pollutant fate and transport. There is considerable overlap across subject areas (e.g.some bioaccumulation papers may be cited in other topical categories). Please use keyword searching of the text to locate related but distributed papers. Use this review only as a guide and please consult the original papers before citing them.

2.
Environ Toxicol Chem ; 40(8): 2085-2097, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34291842

RESUMO

Polychlorinated biphenyl exposure-response relationships for ecologically relevant endpoints in fish vary greatly whether based on lowest-effect thresholds (Berninger and Tillitt 2019) or all-response data (sensitivity analyses), which precludes use of a single fitted model per endpoint to predict risk or injury to mixed fish populations. PCB = polychlorinated biphenyl.


Assuntos
Bifenilos Policlorados , Animais , Peixes , Bifenilos Policlorados/análise , Bifenilos Policlorados/toxicidade , Reprodução
3.
PLoS One ; 14(7): e0219535, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31361767

RESUMO

OBJECTIVE: Voluntary Counseling and Testing for HIV (VCT) and increasing access to male condoms are common strategies to respond to the HIV/AIDS pandemic. Using biological and behavioral outcomes, we compared programs to increase access to VCT, male condoms or both among youth in Western Kenya with the standard available HIV prevention services within this setting. DESIGN: A four arm, unblinded randomized controlled trial. METHODS: The sample includes 10,245 youth aged 17 to 24 randomly assigned to receive community-based VCT, 150 male condoms, both VCT and condoms, or neither program. All had access to standard HIV services available within their communities. Surveys and blood samples for HSV-2 testing were collected at baseline (2009-2010) and at follow up (2011-2013). VCT was offered to all participants at follow up. HSV-2 prevalence, the primary outcome, was assessed using weighted logistic regressions in an intention-to-treat analysis. RESULTS: For the 7,565 respondents surveyed at follow up, (effective tracking rate = 91%), the weighted HSV-2 prevalence was similar across groups (control group = 10.8%, condoms only group = 9.1%, VCT only group = 10.2%, VCT and condoms group = 11.5%). None of the interventions significantly reduced HSV-2 prevalence; the adjusted odds ratios were 0.87 (95% CI: 0.61-1.25) for condoms only, 0.94 (95% CI: 0.64-1.38) for VCT only, and 1.12 (95% CI: 0.79-1.58) for both interventions. The VCT intervention significantly increased HIV testing (adj OR: 3.54, 95% CI: 2.32-5.41 for VCT only, and adj OR: 5.52, 95% CI: 3.90-7.81 for condoms and VCT group). There were no statistically significant effects on risk of HIV, or on other behavioral or knowledge outcomes including self-reported pregnancy rates. CONCLUSION: This study suggests that systematic community-based VCT campaigns (in addition to VCT availability at local health clinics) and condom distribution are unlikely on their own to significantly reduce the prevalence of HSV-2 among youth.


Assuntos
Preservativos , Aconselhamento , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Adolescente , Cultura , Feminino , Seguimentos , Infecções por HIV/diagnóstico , Herpesvirus Humano 2/fisiologia , Humanos , Análise de Intenção de Tratamento , Quênia/epidemiologia , Masculino , População Rural , Adulto Jovem
4.
Environ Toxicol Chem ; 25(10): 2576-83, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17022396

RESUMO

Recent studies by researchers at the U.S. Environmental Protection Agency and U.S. Geological Survey have evaluated the toxicity of Cr in freshwater and marine sediments, primarily during laboratory studies in which clean sediments were spiked with Cr. Results of those studies showed that Cr is relatively insoluble and nontoxic when present in the trivalent form, Cr(III), rather than in the more soluble and more toxic hexavalent form, Cr(VI). The studies concluded that Cr toxicity should be low in sediments with measurable concentrations of acid-volatile sulfide (AVS), because AVS is formed only in anoxic sediments and Cr(VI) is thermodynamically unstable under such conditions. The present study evaluates the toxicity and bioavailability of Cr in sediments associated with chromite ore processing residue (COPR). Ten stations were sampled in the Hackensack River (NJ, USA) to represent a wide range of total Cr concentrations (199-3,970 mg/kg) with minimal interference from potentially toxic, co-occurring chemicals. Sediment toxicity was evaluated using two amphipod tests: The 10-d Ampelisca abdita test (survival as endpoint), and the 28-d Leptocheirus plumulosus test (survival and biomass as endpoints). Measurable concentrations of AVS were present at eight stations, and nearly all Cr was present as Cr(III). In addition, results of electron-microprobe analyses showed that most Cr was associated with phases in which Cr has limited bioavailability (i.e., chromite and iron oxide). Sediment toxicity showed no correlation with concentrations of total Cr, and the maximum no-effect concentration for total Cr was estimated as 1,310 mg/ kg. These results indicate that Cr can be present in sediments associated with COPR at highly elevated concentrations without causing sediment toxicity.


Assuntos
Cromo/toxicidade , Sedimentos Geológicos/química , Disponibilidade Biológica , Cromo/farmacocinética , Microanálise por Sonda Eletrônica
5.
Integr Environ Assess Manag ; 5(4): 515-22, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19545186

RESUMO

The Society of Environmental Toxicology and Chemistry (SETAC) convened an invited workshop (August 2008) to address coordination between ecological risk assessment (ERA) and natural resource damage assessment (NRDA). Although ERA and NRDA activities are performed under a number of statutory and regulatory authorities, the primary focus of the workshop was on ERA and NRDA as currently practiced in the United States under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). This paper presents the findings and conclusions of the Synthesis Work Group, 1 of 3 work groups convened at the workshop. The Synthesis Work Group concluded that the different programmatic objectives and legal requirements of the 2 processes preclude development of a single, integrated ERA/NRDA process. However, although institutional and programmatic impediments exist to integration of the 2 processes, parties are capitalizing on opportunities to coordinate technical and scientific elements of the assessments at a number of locations. Although it is important to recognize and preserve the distinctions between ERA and NRDA, opportunities for data sharing exist, particularly for the characterization of environmental exposures and derivation of ecotoxicological information. Thus, effective coordination is not precluded by the underlying science. Rather, willing participants, accommodating schedules, and recognition of potential efficiencies associated with shared data collection can lead to enhanced coordination and consistency between ERA and NRDA.


Assuntos
Conservação dos Recursos Naturais , Ecologia , Monitoramento Ambiental/métodos , Medição de Risco/métodos
6.
Integr Environ Assess Manag ; 4(2): 156-70, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17994918

RESUMO

In 2000, a set of sediment effect concentrations (SECs) was published for evaluating the toxicity of polychlorinated biphenyls (PCBs) in freshwater, estuarine, and marine sediments. According to the developers, these consensus-based SECs reconcile existing sediment quality guidelines (SQGs) that have been developed using various approaches, reflect causal rather than correlative effects, and can be used to determine the spatial extent of injury to sediment-dwelling organisms. In the present study, a critical evaluation of the SECs was conducted based on the original documents and databases used to develop the underlying SQGs for the SECs, as well as the original documents and data sets used to determine the predictive ability of the SECs. Results of the critical evaluation indicated that the SECs are simple mathematical constructs that share the same limitations as their underlying SQGs. The SECs are questionable "consensus" values, because many of their underlying SQGs are dissimilar, misclassified, or redundant with other SQGs. Because nearly all of the data sets included in the databases used to calculate the underlying SQGs, or to validate the SECs, were affected by elevated concentrations of multiple co-occurring chemicals, it was not possible to-conclusively identify PCBs as the cause of any of the observed sediment toxicity. The SECs, and most of their underlying SQGs, are likely biased by the fact that their underlying databases are composed primarily of PCB concentrations less than 0.5 mg/kg dry weight. Comparisons between the SECs and bioaccumulation-based SQGs calculated using the equilibrium partitioning approach provide no information on whether the SECs are causally related to sediment toxicity. The primary available median lethal concentration (LC50) value for PCBs, determined using spiked-sediment toxicity tests, has limited applicability to most contaminated aquatic environments, because it was determined using an unusually low total organic carbon content. Finally, site-specific application of the SECs indicated that their predictive ability was very low, that concentration-response relationships were not found for a variety of test species and toxicity endpoints at PCB concentrations greater than the SECs, and that some of the highest survival and growth values in the toxicity tests were found at PCB concentrations considerably greater than the SECs. Based on the results of this study, we conclude that the SECs for PCBs should be used only in the screening-level evaluations that typically precede more direct assessments of sediment toxicity at individual study sites, and should not be used to predict the presence of sediment toxicity. Contrary to the conclusions of the SEC developers, the SECs do not reconcile existing SQGs, do not reflect causal effects, and should not be used to determine the spatial extent of injury to sediment-dwelling organisms.


Assuntos
Sedimentos Geológicos , Bifenilos Policlorados/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bases de Dados Factuais , Previsões , Água Doce , Medição de Risco , Água do Mar
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