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1.
Environ Sci Pollut Res Int ; 25(14): 13292-13311, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-27761862

RESUMO

The aim of this study was to jointly show the results of three independent ecotoxicological studies performed to investigate pollutants in three Brazilian tropical reservoirs undergoing accelerated eutrophication. In order to accomplish this goal, the full toxicity identification and evaluation procedure (TIE approach) was performed, at Pampulha (Minas Gerais State) and Salto Grande and Barra Bonita reservoirs (São Paulo State). Acute and chronic toxicity tests were performed using the cladocerans Daphnia similis and Ceriodaphnia dubia (exotic) and Daphnia laevis and Ceriodaphnia silvestrii (native) as test organisms. Results from TIE procedure stage I indicated the existence of nonpolar organic and filterable compounds in the water from Pampulha, probably cyanotoxins, and oxidants as part of the toxic agents. TIE results for sediments identified ammonia (Pampulha and Salto Grande), organic compounds (Pampulha), metals (Pampulha, Barra Bonita, and Salto Grande), and acidity (Salto Grande) as responsible for toxicity. Whole-sediment remediation experiments for Pampulha reservoir confirmed, through reproduction decrease, ammonia and organic compounds as contaminants. Such pollutants represent threats to aquatic biota and must be prevented. Higher temperatures as predicted from global climate change will severely affect tropical shallow reservoirs, accelerating eutrophication, the release of contaminants from sediments, and increasing toxicity.


Assuntos
Eutrofização , Água Doce/análise , Sedimentos Geológicos/química , Animais , Brasil , Cladocera/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Ecotoxicologia , Clima Tropical , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
2.
Ecotoxicol Environ Saf ; 117: 155-63, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25868152

RESUMO

This study aimed to analyze laboratory and field data to assess the ecotoxicological risks of calcium nitrate exposure to freshwater tropical biota. Short-term laboratorial tests resulted in estimated EC50 values of 76.72 (67.32-86.12)mg N-NO3₋ L(-1) for C. silvestrii and 296.46 (277.16-315.76) mg N-NO3₋ L(-1) for C. xanthus. Long-term laboratorial tests generated IC25 values of 5.05 (4.35-5.75) and 28.73 (26.30-31.15) mg N-NO3₋ L(-1) for C. silvestrii and C. xanthus, respectively. The results from in situ mesocosm experiments performed in the Ibirité reservoir (a tropical eutrophic urban water body located in SE Brazil) indicated that C. silvestrii and C. xanthus were not under severe deleterious acute impact due to the treatment because the higher nitrate concentrations determined were 5.2 mg N-NO3₋ L(-1) (t=24 h; sediment-water interface) and 17.5 mg N-NO3₋ L(-1) (t=600 h; interstitial water). However, an abrupt decrease in the densities of Cyanophyceae members and other benthic taxa was observed. In summary, the present work contributes greatly to the toxicity data linked to two taxonomically distinct organisms that have never been screened for calcium nitrate sensitivity. Furthermore, considering the problem of the management and restoration of eutrophic environments, our study reports a comprehensive field assessment that allows the elucidation of the possible toxic impacts caused by the addition of calcium nitrate (a remediation technique) on aquatic and benthic organisms as well as the implications on the aquatic ecosystem as a whole, which may greatly allow expanding the current knowledgebase on the topic.


Assuntos
Compostos de Cálcio/toxicidade , Nitratos/toxicidade , Animais , Organismos Aquáticos , Brasil , Cladocera , Ecossistema , Ecotoxicologia , Água Doce , Risco , Testes de Toxicidade , Clima Tropical
3.
Rev Calid Asist ; 28(1): 28-35, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-22771151

RESUMO

OBJECTIVES: To describe the medication errors in the medication use cycle in a general public hospital, and to identify intervention strategies in relation to the detection and prevention of these errors. METHODS: Descriptive study with cross-sectional design. General public hospital of 190 beds, in Rosario (Argentina). Daily and systematic data collection of the circuit of use of medicines during May 2009. Once the errors were identified and classified, an interdisciplinary group sequentially applied different quality management tools to recognize and weigh causes, and propose solutions. (Flowchart, Cause Effect Diagram, Brainstorming, Nominal Group and Matrix Decision). RESULTS: Information on 60 patients was retrieved during the study period, with 506 medication errors detected. The impact indicators showed the following values: 8.4 errors/patient and 88.6 errors/100 patients-day. From the causes identified, two were defined as relevant: "Double prescription" and "Lack of clear policy". Of the various solutions proposed, an intervention strategy was defined to include a differently designed form for "prescription/indication/administration" in the clinical history which could be updated daily, with a duplicate to Pharmacy for the distribution, as well as a Standard Operating Procedure to standardize this new way of working. CONCLUSION: This work achieved, through quality management, the commitment of a team of health professionals to seek and make changes for patient safety, and to improve the quality of services provided by the hospital.


Assuntos
Erros de Medicação/prevenção & controle , Segurança do Paciente/normas , Gestão da Qualidade Total , Estudos Transversais , Árvores de Decisões , Hospitais Públicos , Humanos , Erros de Medicação/classificação
4.
Water Res ; 46(19): 6463-75, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23069075

RESUMO

The main objective of this study was to perform laboratory experiments on calcium nitrate addition to sediments of a tropical eutrophic urban reservoir (Ibirité reservoir, SE Brazil) to immobilize the reactive soluble phosphorus (RSP) and to evaluate possible geochemical changes and toxic effects caused by this treatment. Reductions of 75 and 89% in the concentration of RSP were observed in the water column and interstitial water, respectively, after 145 days of nitrate addition. The nitrate application increased the rate of autotrophic denitrification, causing a consumption of 98% of the added nitrate and oxidation of 99% of the acid volatile sulfide. As a consequence, there were increases in the sulfate and iron (II) concentrations in the sediment interstitial water and water column, as well as changes in the copper speciation in the sediments. Toxicity tests initially indicated that the high concentrations of nitrate and nitrite in the sediment interstitial water (up to 2300 mg L(-1) and 260 mg L(-1), respectively) were the major cause of mortality of Ceriodaphnia silvestrii and Chironomus xanthus. However, at the end of the experiment, the sediment toxicity was completely removed and a reduction in the 48 h-EC50 of the water was also observed. Based on these results we can say that calcium nitrate treatment proved to be a valuable tool in remediation of eutrophic aquatic ecosystems leading to conditions that can support a great diversity of organisms after a restoration period.


Assuntos
Compostos de Cálcio/química , Água Doce/química , Sedimentos Geológicos/química , Nitratos/química , Fósforo/química , Animais , Brasil , Chironomidae/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Desnitrificação , Recuperação e Remediação Ambiental/economia , Recuperação e Remediação Ambiental/métodos , Eutrofização , Nitrogênio , Oxirredução , Testes de Toxicidade Aguda/métodos , Clima Tropical
5.
Braz. j. biol ; 71(4): 903-914, Nov. 2011. graf, tab
Artigo em Inglês | VETINDEX | ID: lil-606519

RESUMO

This study evaluated the acute toxicity of sediment in a eutrophic reservoir after remediation with a calcium nitrate solution to retain phosphorus. The study involved microcosms of surface sediments and water from the sediment-water interface in the Ibirité reservoir. This reservoir, located in the vicinity of metropolitan Belo Horizonte (Minas Gerais, SE Brazil), is a water body that receives treated effluents from an oil refinery (REGAP-Petrobras), as well as high loads of untreated urban effluents from the city of Ibirité and surrounding areas and industrial effluents from a major industrial park. Incubation times of the treatment experiments were: t = 0, t = 5, t = 10, t = 25, t = 50, t = 85 and t = 135 days. One control microcosm and three treated microcosms were analysed in each time interval. Acute toxicity of water samples was assessed with Ceriodaphnia silvestrii Daday, 1902 and that of bulk sediment samples with Chironomus xanthus Rempel, 1939. Toxicity tests were carried out concomitantly with chemical analyses of dissolved inorganic nitrogen species (ammonia, nitrate and nitrite), sulfate and metals in the water samples of the microcosms. Acid volatile sulfides (AVS), simultaneously extracted metal (SEM) and potentially bioavailable metal were analyzed in bulk sediment samples. Neither of the tested organisms showed toxicity in the control microcosm samples. The water column of the treated microcosm showed toxicity to C. silvestrii, starting at t = 10 days, while the sediment pore water toxicity started at t = 0 day. However, toxicity was found to decline from t = 85 days to t = 135 days. Sediments showed toxicity to C. xanthus during the entire experiment, except at the longest incubation time (t = 135 days). The overall results indicate that nitrate, which reached concentrations exceeding 1,200 mg N-NO3- L-¹ in the sediment pore water of the treated microcosms, was most probably responsible for the toxicity of the samples. Although the calcium nitrate technology proved effective in retaining phosphorus, promoting sediment oxidation via denitrification, from the ecotoxicological standpoint and under the experimental conditions of this study, the application of nitrate for remediation of the sediments in the Ibirité reservoir did not prove effective up to a period of 135 days of incubation. However, we presume that after longer periods of incubation, treated sediments may recover their ability to sustain a benthic community. More advanced experiments are planned involving longer incubation times, thus extending the denitrification process, which may lead to a higher phosphorus retention capacity and to more complete abatement of sediment toxicity.


O presente trabalho visou à avaliação da toxicidade aguda da aplicação de solução de nitrato de cálcio, como procedimento para remediação dos sedimentos de um reservatório eutrofizado com vistas à retenção de fósforo. O estudo foi realizado através de microcosmos com sedimento e amostras de interface sedimento-água da Represa Ibirité. A represa, situada na região metropolitana de Belo Horizonte (Minas Gerais, Brasil), é corpo receptor de efluentes tratados de refinaria de petróleo (REGAP-Petrobras), de altas cargas de esgoto sanitário não tratado da cidade de Ibirité e áreas vizinhas, e de efluentes industriais de importante parque industrial. Os tempos de incubação dos experimentos foram: t = 0, t = 5; t = 10; t = 25; t = 50; t = 85; e t = 135 dias. Em cada um deles, foram analisadas amostras de um microcosmo-controle e três microcosmos-tratamento. A Ceriodaphnia silvestrii Daday, 1902 foi o organismo utilizado para avaliação da toxicidade aguda das amostras de água, enquanto que o Chironomus xanthus Rempel, 1939 foi empregado para a avaliação do sedimento integral. Paralelamente aos testes de toxicidade, foram realizadas análises químicas da série nitrogenada (amônia, nitrato e nitrito), sulfato, e metais nas amostras de água. Nos sedimentos foram analisados os sulfetos volatilizáveis por acidificação (SVA), metais extraídos simultaneamente (MES) e metais potencialmente biodisponíveis. Tanto as amostras de água como dos sedimentos totais dos microcosmos-controle não se mostraram tóxicos aos organismos testados. As amostras de água de interface sedimento-água dos micorocosmos-tratamento foram tóxicas para a C. silvestrii desde o tempo t = 10 dias e as amostras de águas intersticiais, desde o período t = 0. No entanto, foi notada uma diminuição da toxicidade do tempo t = 85 para t = 135 dias. Para o organismo C. xanthus, os sedimentos em tratamento se mostraram tóxicos durante todo o experimento, exceto no tempo t = 135 dias. Os resultados mostraram que o nitrato, com concentração superior a 1.200 mg N-NO3- L-¹ nas amostras de água intersticial dos sedimentos dos microcosmos-tratamentos, é a causa mais provável da toxicidade das amostras. Embora a tecnologia de adição de nitrato tenha se mostrado eficaz na retenção de fósforo nos sedimentos, pois causa a oxidação dos sedimentos através do incremento substancialmente da taxa de desnitrificaçao, do ponto de vista ecotoxicológico e para as condições experimentais deste trabalho, a aplicação do nitrato como forma de intervenção para remediação dos sedimentos da Represa Ibirité não se mostrou adequada até o período de 135 dias. Após este período, presume-se que os sedimentos tratados possam recuperar a capacidade de sustentar uma comunidade bentônica. Experimentos mais avançados foram planejados, visando um tempo de incubação mais estendido, que, por conseguinte, pode levar a uma maior capacidade de retenção de P e ao abatimento total da toxicidade dos sedimentos e da água, devido a um maior avanço do processo da desnitrificação.


Assuntos
Poluição da Água/análise , Sedimentos/análise , Chironomidae , Eutrofização , Desnitrificação
6.
Water Sci Technol ; 62(6): 1312-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20861545

RESUMO

As part of an experimental project on the treatment of bleach plant effluents the results of biodegradability and toxicity assessment of effluents from a bench-scale horizontal anaerobic immobilized bioreactor (HAIB) are discussed in this paper. The biodegradability of the bleach plant effluents from a Kraft pulp mill treated in the HAIB was evaluated using the modified Zahn-Wellens test. The inoculum came from a pulp mill wastewater treatment plant and the dissolved organic carbon (DOC) was used as the indicator of organic matter removal. The acute and chronic toxicity removal during the anaerobic treatment was estimated using Daphnia similis and Ceriodaphnia silvestrii respectively. Moreover, the evaluation of chromosome aberrations (CA), micronucleus frequencies (MN) and mitotic index (IM) in Allium cepa cells were used as genotoxicity indicators. The results indicate that the effluents from the anaerobic reactor are amenable to aerobic polishing. Acute and chronic toxicity were reduced by 90 and 81%, respectively. The largest CA and MN incidence in the meristematic cells of A. cepa were observed after exposure to the raw bleach plant effluent. The HAIB was able to reduce the acute and chronic toxicity as well as chromosome aberrations and the occurrence of micronucleus.


Assuntos
Anaerobiose , Reatores Biológicos/microbiologia , Clareadores , Hidrocarbonetos Clorados , Poluentes Químicos da Água , Purificação da Água/métodos , Aerobiose , Animais , Biodegradação Ambiental , Clareadores/análise , Clareadores/toxicidade , Daphnia/efeitos dos fármacos , Daphnia/crescimento & desenvolvimento , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/toxicidade , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Cebolas/efeitos dos fármacos , Cebolas/genética , Cebolas/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/genética , Sementes/crescimento & desenvolvimento , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Purificação da Água/instrumentação
7.
Water Sci Technol ; 61(1): 199-205, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20057106

RESUMO

Effluents originated in cellulose pulp manufacturing processes are usually toxic and recalcitrant, specially the bleaching effluents, which exhibit high contents of aromatic compounds (e.g. residual lignin derivates). Although biological processes are normally used, their efficiency for the removal of toxic lignin derivates is low. The toxicity and recalcitrance of a bleached Kraft pulp mill were assessed through bioassays and ultraviolet absorption measurements, i.e. acid soluble lignin (ASL), UV(280), and specific ultraviolet absorption (SUVA), before and after treatment by an integrated system comprised of an anaerobic packed-bed bioreactor and oxidation step with ozone. Furthermore, adsorbable organic halides (AOX) were measured. The results demonstrated not only that the toxic recalcitrant compounds can be removed successfully using integrated system, but also the ultraviolet absorption measurements can be an interesting control-parameter in a wastewater treatment.


Assuntos
Reatores Biológicos , Ozônio/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Anaerobiose , Biodegradação Ambiental , Celulose , Eucalyptus , Lignina/análise , Ozônio/toxicidade , Purificação da Água/normas , Madeira
8.
Farm Hosp ; 28(5): 327-33, 2004.
Artigo em Espanhol | MEDLINE | ID: mdl-15504090

RESUMO

OBJECTIVE: To compare structures, procedures and results of the pharmaceutical management of institutional pharmacies in the city of Rosario (Argentina), to define the current situation and thus recommend changes. METHOD: Descriptive study, using a questionnaire and quality indicators of an Accreditation Program of Hospital Pharmacies. Evaluated dimensions: selection, acquisition, reception, storage and stock control of drugs and medical devices. Data was collected for a one-year-period in order to obtain indicators. After tabulation, data was discussed in meetings with all the pharmacists that participate in this study, in order to evaluate the situation and propose changes for the Pharmacies, as well as to evaluate the Program based on usefulness of these indicators. RESULTS: The general results illustrate how each institution has different health policies. 43.2% of indicators were answered, 67.6% reached standard values. CONCLUSIONS: This work allowed for an exhaustive analysis of the current situation. The pharmacists made proposals and unified criteria in order to obtain an improved use of the economic resources of each institution.


Assuntos
Serviço de Farmácia Hospitalar/organização & administração , Indicadores de Qualidade em Assistência à Saúde , Argentina , Humanos , Serviço de Farmácia Hospitalar/normas , Inquéritos e Questionários , Gestão da Qualidade Total/organização & administração , Gestão da Qualidade Total/normas
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