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1.
J Environ Manage ; 344: 118513, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37418917

RESUMO

The assessment of waste ecotoxicity (hazardous property HP14 in the European Union) is fundamental for proper waste classification and safe application/disposal. Biotests are relevant for evaluating waste complex matrices, but their efficiency is crucial to encourage their adoption at the industrial level. This work aims at evaluating possibilities of improving the efficiency of a biotest battery previously suggested in the literature, regarding test selection, duration, and/or laboratory resources optimization. Fresh incineration bottom ash (IBA) was the case study. The test battery analysed included standard aquatic (bacteria, microalgae, macrophytes, daphnids, rotifers, fairy shrimp) and terrestrial (bacteria, plants, earthworms, collembolans) organisms. The assessment followed an Extended Limit Test design (three dilutions of eluate or solid IBA) and the Lowest Ineffective Dilution (LID-approach) for ecotoxicity classification. The results emphasize the importance of testing different species. It was also evidenced that tests with daphnids and earthworms may be shortened to 24 h; the miniaturization of tests is suitable as e.g. differential sensitivity of microalgae and macrophytes was captured with low variability; alternative testing kits can be used when methodological difficulties are found. Microalgae were more sensitive than macrophytes. Similar results were found for the Thamnotoxkit and daphnids test for eluates with natural pH, so the former may be used as an alternative. B. rapa was the most sensitive organism, suggesting that it may be tested as the only terrestrial plant species and that minimum test duration is appropriate. F. candida does not appear to add information to the battery. The differences in sensitivity of A. fischeri and E. fetida compared to the remaining species were not significant enough to exclude them from the battery. Thus, this work suggests a biotest battery to test IBA comprising aquatic tests - Aliivibrio fischeri, Raphidocelis subcapitata (miniaturised test), and Daphnia magna (24 h when clear deleterious effects are observed) or Thamnocephalus platyurus (toxkit) - and terrestrial tests - Arthrobacter globiformis, Brassica rapa (14 d), and Eisenia fetida (24 h). Testing waste with natural pH is also recommended. The Extended Limit Test design considering the LID-approach seems useful in waste testing, particularly for the industry, involving low effort, test material requirements, and few laboratory resources. The LID-approach allowed for differentiating ecotoxic from non-ecotoxic effects and captured different sensitivities between species. Ecotoxicological assessment of other waste may benefit from these recommendations, but caution should be taken given the properties of each waste type.


Assuntos
Cinza de Carvão , Incineração , União Europeia , Plantas
2.
Crit Rev Toxicol ; 49(5): 411-429, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31268799

RESUMO

Caenorhabditis elegans has been an invaluable model organism in research fields such as developmental biology and neurobiology. Neurotoxicity is one of the subfields greatly profiting from the C. elegans model within biomedical context, while the corresponding potential of the organism applied to environmental studies is relevant but has been largely underexplored. Within the biomedical scope, the implication of metals and organic chemicals with pesticide activity (hereinafter designated as pesticides) in the etiology of several neurodegenerative diseases has been extensively investigated using this nematode as a primary model organism. Additionally, as a well-known experimental model bearing high sensitivity to different contaminants and representing important functional levels in soil and aquatic ecosystems, C. elegans has high potential to be extensively integrated within Environmental Risk Assessment (ERA) routines. In spite of the recognition of some regulatory agencies, this actual step has yet to be made. The purpose of this review is to discuss the major advantages supporting the inclusion of C. elegans in lower tiers of ERA. Special emphasis was given to its sensitivity to metals and pesticides, which is similar to that of other model organisms commonly used in ERA (e.g. Daphnia magna and Eisenia sp.), and to the large array of endpoints that can be tested with the species, both concerning the aquatic and the soil compartments. The inclusion of C. elegans testing may hence represent a relevant advance in ERA, providing ecologically relevant insights toward improvement of the regulatory capacity for establishing appropriate environmental protection benchmarks.


Assuntos
Caenorhabditis elegans/fisiologia , Monitoramento Ambiental/métodos , Animais , Metais/toxicidade , Modelos Teóricos , Praguicidas/toxicidade , Medição de Risco
3.
Sci Total Environ ; 668: 1289-1297, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31018468

RESUMO

Freshwater ecosystems face widespread diffuse and point-source contamination. Species Sensitivity Distributions (SSDs) have been used as a tool to determine chemical concentration benchmarks that represent protective levels for most species in the environment. Here we used a SSD approach to assess on the adequacy of standard planktonic organisms to reflect the response of benthic communities, critically supporting the structure and function of lotic ecosystems. For the purpose, SSDs reflecting non-lethal responses of standard planktonic and selected benthic organisms were built based on EC50 values (collected in the literature or estimated following testing herein) regarding three model contaminants: potassium dichromate (PD), 3,5-dichlorophenol (DCP) and lead chloride (LC). The derived HC5 estimates were discriminatory between chemicals and the uncertainty associated with the estimate was remarkably low. The HC5 estimates with corresponding uncertainty were generally within the same order of magnitude for the three chemicals tested, with better discrimination between chemicals regarding their hazardous potential being achieved for benthic organisms: DCP was clearly less hazardous than PD, but LC tends to be as hazardous as PD and DCP (assuming the confidence interval ranges). Moreover, benthic communities were more sensitive to both DCP and PD, in this later case the HC5 being lower by more than one order of magnitude than that found for planktonic communities; for LC, confidence intervals overlapped, preventing a feasible assumption regarding differential sensitivity of the compared communities. Microphytobenthos was highlighted as the most sensitive group to the three tested chemicals in SSDs covering the benthic compartment, while SSDs with planktonic organisms did not consistently show trends in sensitivity ordering. Overall, our results suggest that protective benchmarks retrieved from SSDs built with the responses of standard planktonic organisms (which are the most commonly used for regulation purposes) do not adequately protect benthic communities.


Assuntos
Benchmarking/métodos , Água Doce/química , Oligoquetos/efeitos dos fármacos , Plâncton/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Conservação dos Recursos Naturais/métodos , Ecossistema , Ecotoxicologia , Medição de Risco , Especificidade da Espécie , Poluentes Químicos da Água/análise
4.
Environ Monit Assess ; 79(1): 75-100, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12381024

RESUMO

The State of Minas Gerais represents one of Brazil's most outstanding mining resources. The contamination of river water from kaolin processing activities may be harmful to people in the way of slow but chronic poisoning. On the other hand, the discharge of untreated or inadequately treated domestic sewage into aquatic environments can also cause deleterious effects to the health. However, no reliable figures are available for pollutant occurrences in river water. This draws attention to the very precarious situation that exists with respect to pollution by organic and inorganic toxic wastes, especially with respect to humans and fauna in all its expressions. Thus, with the purpose of establishing a preliminary report to trace out industrialisation outcomes, samples of river water, vegetation and fish were collected and analysed to detect pollutant inputs. The concentration of metals was determined in suspended particle, vegetation and fish, while those of nitrite, nitrate, phosphate and chloride were determined in river water samples. The concentration of dissolved oxygen (DO) was measured in river water at the time of collection. Chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were also determined. Metal inputs in the samples analysed appeared to be related to effluent discharges into the rivers. The suspended particles showed high concentrations (in mg kg(-1)) of zinc (62 600) and aluminium (559 000), while vegetation samples collected near rivers were heavily contaminated with iron (7680). The fishes examined were contaminated with chromium (1.5 mg kg(-1)). In general, the concentrations of nitrite, nitrate, chloride, phosphate and BOD in river water were lower than the maximum values established by the Brazilian Environmental Standards.


Assuntos
Metais Pesados/análise , Esgotos , Poluentes da Água/análise , Abastecimento de Água , Animais , Brasil , Cromo/análise , Cromo/farmacocinética , Monitoramento Ambiental , Peixes , Indústrias , Metais Pesados/farmacocinética , Mineração , Oxigênio/metabolismo , Plantas , Distribuição Tecidual , Poluentes da Água/farmacocinética
5.
Cancer ; 88(12): 2859-67, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10870073

RESUMO

BACKGROUND: Delirium is a common neuropsychiatric complication in patients with advanced cancer. The Memorial Delirium Assessment Scale (MDAS) is a recently developed 10-item severity rating instrument. The purpose of the current prospective study was to further assess the clinical utility, factor structure, and validity of the MDAS in a relatively homogeneous population of patients with advanced cancer. METHODS: Study entry of 104 patients occurred on their consecutive admission to a tertiary-level, acute palliative care unit in a university-affiliated teaching hospital. Patients underwent regular cognitive screening using the Mini-Mental State Examination, and serial monitoring of delirium using standardized semistructured interviews and MDAS ratings, up to the study endpoints of either patient discharge or death. RESULTS: Seventy-one patients met Diagnostic and Statistical Manual (of Mental Disorders)-IV criteria for a first episode of delirium. In 15 of 71 (21%) patients with a first episode of delirium, the first MDAS ratings were prorated because of dyspnea, fatigue, or profound delirium. In the remaining 56 patients (79%), the first MDAS ratings were rated fully and therefore evaluable. Correlations among the scale items ranged from moderate to low (correlation coefficient [r] = 0.68-0.02). Analysis of the pattern of factor loadings identified two primary correlated factors: global cognitive (Factor I) and neurobehavioral (Factor II) (r = 0.33). Cronbach alpha coefficients for Factors I and II were 0.8 and 0.66, respectively, indicating a relatively high level of correlation for items within each. The Cronbach alpha coefficient for all 10 items was 0.78, suggesting a general underlying factor. In a larger sample of complete MDAS ratings (n = 330) a cutoff total MDAS score of 7 of 30 yielded the highest sensitivity (98%) and specificity (96%) for delirium diagnosis. The MDAS was correlated moderately with the Mini-Mental State Examination (r = 0.55). CONCLUSIONS: The authors concluded that the MDAS structure is representative of the many features of delirium, broadly grouped as global cognitive and neurobehavioral dimensions. Prorating item scores is necessary in approximately 20% of advanced cancer patients with delirium. This poses potential limitations on the applicability of the MDAS in research. Conversely, the ability to prorate item scores confers a clinical advantage to the instrument when assessing delirium in a patient population with advanced cancer.


Assuntos
Transtornos Cognitivos/diagnóstico , Delírio/diagnóstico , Entrevista Psiquiátrica Padronizada/normas , Neoplasias/psicologia , Idoso , Transtornos Cognitivos/etiologia , Delírio/etiologia , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Cuidados Paliativos , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Rev Esp Cardiol ; 51(8): 611-9, 1998 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-9780774

RESUMO

The present work describes the process by which the pilot project of clinical management of the Hospital Complex Juan Canalejo, designated as "Heart Area", was implemented. In the first section, the needs and reasons that led to the undertaking of this project are explained. The project's objectives and operative strategies are listed. In the Material and Methods section, three basic aspects of the "Heart Area" are described: selection criteria of the "Area", its structure and function, and its foundation and development. In the Results section, we compare the activity undertaken in the "Area" to the situation present prior to its implementation, in relation to quality and costs. Finally, in the Conclusions, we comment on the important implications that our project can have within the Hospital Complex Juan Canalejo as well as in the health care field in general.


Assuntos
Serviço Hospitalar de Cardiologia , Procedimentos Cirúrgicos Cardíacos , Serviço Hospitalar de Cardiologia/economia , Serviço Hospitalar de Cardiologia/organização & administração , Emergências , Estudos de Avaliação como Assunto , Cardiopatias/complicações , Cardiopatias/cirurgia , Cardiopatias/terapia , Humanos , Projetos Piloto , Espanha , Procedimentos Cirúrgicos Operatórios
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