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1.
Intern Med J ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38966996

RESUMO

BACKGROUND: Use of immune checkpoint inhibitors is growing, but clinical trial data may not apply to Indigenous patients or patients living in remote areas. AIMS: To provide real-world incidence of immune-related adverse events (irAE) in the Top End of the Northern Territory and compare incidence between demographic subgroups. METHODS: This retrospective, observational, cohort study collected data from electronic records of patients living in the Top End with solid organ cancer treated with immunotherapy between January 2016 and December 2021. The primary outcome was cumulative incidence of any-grade and severe irAE. Secondary outcomes were overall survival, treatment duration and reason for treatment discontinuation. RESULTS: Two hundred and twenty-six patients received immunotherapy. Forty-eight (21%) lived in a remote or very remote area, and 36 (16%) were Indigenous. Cumulative incidence of any-grade irAE was 54% (122/226 patients); incidence of severe irAE was 26% (59/226 patients). Rates were similar between Indigenous and non-Indigenous patients of any-grade (42% vs 56%, P = 0.11) and severe (11% vs 18%, P = 0.29) irAE. However, Indigenous patients had shorter treatment duration, more frequently discontinued treatment due to patient preference and appeared to have shorter median overall survival than non-Indigenous patients (17.1 vs 30.4 months; hazard ratio (HR) = 1.5, 95% confidence interval (CI) = 0.92-2.66). There was no difference in mortality between remote and urban patients (median overall survival 27.5 vs 30.2 months; HR = 1.1, 95% CI = 0.7-1.7). CONCLUSIONS: Rates of irAE in our cohort are comparable to those in the published literature. There was no significant difference in any-grade or severe irAE incidence observed between Indigenous and non-Indigenous patients.

2.
AIDS Patient Care STDS ; 38(7): 330-339, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38985567

RESUMO

Although enacted and internalized stigma is a continuing problem for people living with HIV (PLWH) in Southeast Asia, there is little understanding of how PLWH cope with discrimination, exclusion, and other negative outcomes caused by HIV-related stigmatization. This article aims to bridge this gap by analyzing the lived experiences of HIV-related stigmatization and coping strategies among 30 people with HIV in Myanmar, a country heavily influenced by religion, especially Buddhism. Among the 30 study participants, 20 were female and 10 were male, with ages ranging from 18 to 50 years. Through the lens of Bourdieu's concepts of habitus, field, and capital, this article first elucidates the various forms of stigmatization in family, work, social, and other settings as symbolic violence on people with HIV. The present article shows that spirituality serves as a perceptual and action framework for people with HIV to generate reflexivity toward their HIV infection and related stigmatization and to further engage in agentic responses. More importantly, this article demonstrates how people with HIV draw on spirituality to support peers in reclaiming control over their lives and how they are perceived by society. The findings indicate that the local context, especially cultural and religious resources, should be considered when developing interventions to mitigate HIV-related stigmatization in Southeast Asia.


Assuntos
Adaptação Psicológica , Infecções por HIV , Estigma Social , Espiritualidade , Humanos , Mianmar , Masculino , Infecções por HIV/psicologia , Feminino , Adulto , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Estereotipagem , Apoio Social , Pesquisa Qualitativa , Entrevistas como Assunto , Capacidades de Enfrentamento
3.
AIDS Care ; 36(2): 255-262, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37674375

RESUMO

Stigma has heavily impacted People Living with HIV (PLWH). Limited studies report on how social support affects HIV-related stigma and perceived stress, especially in Myanmar. During first seven months of 2020, a random sample of 248 eligible PLWH were contacted from a private, closed Facebook group with more than 18,000 Myanmar people, where 90% of the members were PLWH. Variables collected included demographics data, perceived stress, social support, and HIV stigma. After controlling for the effects of demographic variables, the path from HIV stigma to perceived stress (direct effect ß = 0.40) and though the mediation of social support was significant (indirect effect ß = 0.014). However, the mediating effect of social support was non-significant between HIV stigma and perceived stress. This exploratory study shows that social support did not have the expected effect of decreasing perceived stress in PLWH in Myanmar. Interventions to reduce HIV stigma to decrease perceived stress should consider other strategies, e.g., spirituality-based practice, to reduce perceived stress in Myanmar PLWH.


Assuntos
Infecções por HIV , HIV , Humanos , Estigma Social , Apoio Social , Estresse Psicológico
4.
AIDS Behav ; 27(8): 2751-2762, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36723769

RESUMO

Characterizing HIV-related stigma and its impacts are important for interventions toward their elimination. A cross-sectional study was conducted in 2016 to evaluate enacted and internalized stigma among adult people living with HIV (PLWH) across four cities in Myanmar using the India Stigma Index questionnaire. Multivariable regression analyses were performed to determine differences in measured enacted and internalized stigma outcomes. Among 1,006 participants, 89% reported any stigma indicator, 47% enacted stigma, and 87% internalized stigma. In regression analysis, city and duration of illness were associated with higher enacted stigma, and younger age was associated with higher internalized stigma. Those with HIV duration > 7.4 years had mean enacted stigma nearly 2 units higher than the overall mean. Internalized stigma increased with duration of illness and leveled off at 5 years. PLWH from smaller cities experienced lower stigma. In Myanmar, nearly 90% of PLWH experience stigma, results that reflect a unique transition point.


Assuntos
Infecções por HIV , Adulto , Humanos , Estudos Transversais , Mianmar , Infecções por HIV/epidemiologia , Estigma Social , Cidades
5.
J Nurs Meas ; 30(4): 603-626, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36526419

RESUMO

Background and Purpose: Reliable instruments for the measurement of perceived stress in people living with HIV (PLHIV) are crucial. However, there is no Myanmar version of such an instrument. Methods: We adapted the 35-item Perceived Stress Scale for People Living with HIV/AIDS (PSSHIV) into a Myanmar version (PSSHIV-M), and 150 PLHIV completed the survey. Results: The 31-item PSSHIV-M with a five-factor structure has a Cronbach's alpha of .85 to .95. Construct validity was demonstrated for the instrument, and the findings of Rasch analysis also suggest evidence of reliability and validity. Conclusions: The psychometric properties of the 31-item PSSHIV-M with a five-factor structure support its efficacy in ascertaining how HIV perceived stress affects Myanmar PLHIV. It could also facilitate the development of stress management interventions for that population.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários , Estresse Psicológico
6.
J Assoc Nurses AIDS Care ; 33(5): 559-566, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35862633

RESUMO

ABSTRACT: HIV is a highly stigmatized and stressful condition for people with HIV (PWH). As a country heavily influenced by religion, especially Buddhism, we explore how the perceived stress from HIV stigma interacts with the mediator of mindfulness on PWH in Myanmar. From January to July 2020, a sample of 248 eligible PWH was recruited by quasi-random sampling methods from a private Facebook group in Myanmar. Data on demographics, HIV stigma, mindfulness, and perceived stress were collected. The bias-corrected percentile bootstrap method was used to test multiple mediation analyses. The path from perceived HIV stigma to perceived stress (direct effect ß = 0.16) and the mediating effect of mindfulness on that stress were significant (indirect effect accounts for 45.15% of total effect). The findings indicate that interventions enhancing mindfulness-based practice should be considered to reduce HIV stigma and, therefore, lower perceived stress among PWH in Myanmar.


Assuntos
Infecções por HIV , Atenção Plena , Estudos Transversais , Humanos , Mianmar , Estigma Social , Estresse Psicológico
7.
Nutrients ; 14(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35215393

RESUMO

Underlying pathophysiological mechanisms drive excessive clustering of cardiometabolic risk factors, causing metabolic syndrome (MetS). MetS status may transform as adolescents transition to young adulthood. This study investigated the latent clustering structure and its stability for MetS during adolescence, and assessed the anthropometric and clinical metabolic determinants for MetS transformation. A community-based representative adolescent cohort (n = 1516) was evaluated for MetS using four diagnostic criteria, and was followed for 2.2 years to identify new-onset MetS. The clustering structure underlying cardiometabolic parameters was stable across adolescence; both comprised a fat-blood pressure (BP)-glucose three-factor structure (total variance explained: 68.8% and 69.7% at baseline and follow-up, respectively). Among adolescents with MetS-negative at baseline, 3.2-4.4% had incident MetS after 2.2 years. Among adolescents with MetS-positive at baseline, 52.0-61.9% experienced MetS remission, and 38.1-48.0% experienced MetS persistence. Increased systolic BP (SBP) was associated with a high MetS incidence risk, while decreased levels of SBP and glucose were associated with MetS remission. Compared with adolescents with a normal metabolic status at baseline, those with an initial abdominal obesity and increased triglycerides level had a 15.0- and 5.7-fold greater risk for persistent abnormality, respectively. Abdominal obesity and low high-density lipoprotein cholesterol are two abnormal MetS components that highly persist during adolescence, and are the intervention targets for reducing the future risk of cardiometabolic disorders.


Assuntos
Síndrome Metabólica , Adolescente , Adulto , Fatores de Risco Cardiometabólico , Humanos , Obesidade Abdominal/epidemiologia , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
8.
Mindfulness (N Y) ; 13(1): 188-197, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34777622

RESUMO

Objectives: Valid and reliable instruments for the measurement of mindfulness are crucial for people living with HIV. However, there was no Myanmar version of such an instrument. Methods: We adapted the English version of the 12-item Cognitive and Affective Mindfulness Scale-Revised (CAMS-R) based on standard cross-cultural procedures. By randomly sampling methods, a sample of 248 eligible people living with HIV was contacted from a closed Myanmar Facebook group; 159 PLHIV completed the initial 12-item version of the adapted survey. Results: Three items were removed due to low item-to-total correlations of the corrected item-total correlation as well as having infit and outfit mean squares outside the range of 0.6 to 1.4. After deleting the 3 items, the three-factor structure was confirmed by confirmatory factor analysis, which indicated good model fit. The resultant 9-item CAMS-R in Myanmar (CAMS-R-M-2) achieved good internal reliability (Cronbach's α of 0.75 to 0.87, and the corrected item-total correlation ranged from 0.44 to 0.81). Construct validity of the scale was demonstrated by significant association with self-reported HIV stigma and social support levels (r = 0.63, and - 0.53). In Rasch analysis, the infit and outfit mean squares for each item ranged from 0.49 to 1.24, and the person reliability was 2.17 and the separation index was 0.83. Conclusions: The 9-item CAMS-R-M-2 with a three-factor structure has good reliability and validity. Higher total scores and subscale score reflected greater mindfulness qualities in people living with HIV in Myanmar.

9.
AIDS Care ; 34(6): 762-770, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33749465

RESUMO

In Myanmar, an Asian country with one of the highest HIV-1 prevalence rates, counseling prior to initiating antiretroviral therapy (ART) is standard care, either by a healthcare worker (standard counselor, SC) or trained counselor who is also living with HIV (peer counselor, PC). PC is commonly utilized in Myanmar and other resource-limited settings. However, its benefit over SC is unclear. We conducted a cross-sectional survey of people living with HIV (PLWH), who completed either only PC or only SC before treatment initiation across four cities in Myanmar. Participants were evaluated for HIV knowledge, stigma, antiretroviral adherence, barriers to care, social support satisfaction and attitudes regarding both counseling processes. Bivariate analyses and multivariable mixed effects modeling were conducted to compare differences in these measures among PC and SC participants. Among 1006 participants (49% PC; 51% SC), 52% were females and median age was 37 years in those receiving PC and 40 years in those receiving SC. More than 70% of participants in both groups achieved up to grade school education. The average duration since HIV diagnosis was 4.6 years for PC and 5.7 years for SC participants. HIV knowledge and attitudes regarding counseling were good in both groups and more PC participants credited their HIV counselor for knowledge (75% vs 63%, p < 0.001). Compared to SC, PC participants had lower enacted stigma (Incidence Rate Ratio (IRR) 0.75, Confidence Interval (CI) [0.65, 0.86]), mean internalized stigma (-0.24, CI [-0.34, -0.14]), and risk of antiretroviral therapy non-adherence (Odds Ratio 0.59, CI [0.40, 0.88]), while reporting higher levels of barriers to care (9.63, CI [8.20, 11.75]). Our findings demonstrate potential benefits of PC compared to SC, and support the utilization of PC to enhance HIV health outcomes within the unique societal and geographical context of Myanmar, and possibly beyond.


Assuntos
Infecções por HIV , Adulto , Antirretrovirais/uso terapêutico , Aconselhamento , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Adesão à Medicação/psicologia , Mianmar
10.
J Acquir Immune Defic Syndr ; 89(1): 19-26, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34542090

RESUMO

INTRODUCTION: Understanding social and structural barriers that determine antiretroviral therapy (ART) adherence can improve care. Assessment of such factors is limited in Myanmar, a country with high HIV prevalence and increasing number of people living with HIV initiating ART. METHODS: Questionnaires were administered to adults with HIV across 4 Myanmar cities to estimate adherence and its potential determinants, including HIV knowledge, social support, barriers to care, enacted and internalized stigma, and engagement in peer-to-peer HIV counseling (PC). Associations were determined using logistic mixed-effects modeling. RESULTS: Among 956 participants, the mean age was 39 years, 52% were female, 36% had CD4 <350 cells/mm3, and 50% received pre-ART PC. Good adherence was reported by 74% of participants who had better HIV knowledge than those reporting nonadherence. Among nonadherent, 44% were forgetful and 81% were careless about taking ART. Among all participants, most (53%) were very satisfied with their social support and 79% reported lack of financial resources as barriers to care. Participants most frequently reported being viewed differently by others (30%) and feeling as if they were paying for past karma or sins because of their HIV diagnosis (66%). Enacted stigma (odds ratio 0.86; 95% confidence interval 0.79 to 0.92, P < 0.01) and internalized stigma (odds ratio 0.73; 95% confidence interval: 0.56 to 0.95, P = 0.023) were associated with worse adherence. CONCLUSIONS: Increased self-reported ART adherence in Myanmar is associated with less enacted and internalized stigma. These findings suggest the benefit of developing and promoting adherence interventions, which are focused on mitigating HIV-related stigma in the county.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adulto , Fármacos Anti-HIV/uso terapêutico , Antirretrovirais/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Humanos , Adesão à Medicação , Mianmar/epidemiologia , Estigma Social
11.
Front Psychol ; 12: 707142, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557132

RESUMO

Introduction: Valid and reliable instruments are crucial for measuring perceived social support among people living with HIV (PLHIV). We aimed to investigate the psychometric properties of the English version of the 19-item Medical Outcomes Study Social Support Survey (MOS-SSS) adapted for PLHIV in Myanmar. Methods: Based on a standard cross-cultural procedure, we adapted the MOS-SSS and formed a Myanmar version of the scale (MOS-SSS-M), and then tested its validity and reliability. A sample of 250 eligible PLHIV was collected from a closed Facebook group that included more than 10,000 Myanmars, most of whom were PLHIV. Results: The MOS-SSS-M achieved a Cronbach's α of 0.82-0.95. Confirmatory factor analysis revealed an acceptable fit index for the four-factor structure. Construct validity was demonstrated by significant association with self-reported HIV stigma and stress levels, and further confirmed by the findings of Rasch analysis. Conclusion: The MOS-SSS-M with a four-factor structure can be used to measure the level and categories of perceived social support among PLHIV in Myanmar.

12.
BMC Public Health ; 21(1): 1663, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517850

RESUMO

BACKGROUND: HIV stigma is a common barrier to HIV prevention, testing, and treatment adherence, especially for low- and middle-income countries such as Myanmar. However, there was no validated Myanmar version of a stigma scale. Therefore, we adapted the English version of the 40-item Berger's HIV stigma scale and the 7-item Indian HIV stigma scale into a 47-item Myanmar HIV stigma scale and then evaluated the scale's psychometric properties. METHOD: From January 2020 to May 2020, using random sampling methods, 216 eligible Myanmar people living with HIV/AIDS (PLWHA) were contacted from a closed Facebook group that included more than 10,000 PLWHA. A sample of 156 Myanmar PLWHA completed the online self-reported survey. RESULTS: A six-factor structure for the scale was determined through exploratory factor analysis, explaining 68.23% of the total variance. After deleting 12 items, the 35-item HIV stigma scale achieved Cronbach 's α of 0.72 to 0.95. Construct validity of the scale was demonstrated by significant association with self-reported depression and social support levels (r = 0.60, and - 0.77, p < 0.01). In Rasch analysis, the scale achieved person reliability of 3.40 and 1.53 and a separation index of 0.92 and 0.70. The infit and outfit mean squares for each item ranged from 0.68 to 1.40. No differential item functioning across gender or educational level was found. CONCLUSIONS: The psychometric properties of the 35-item Myanmar version of the HIV stigma scale support it as a measure of stigma among PLWHA in Myanmar. This instrument could help healthcare providers to better understand how stigma operates in PLWHA and to develop tailored stigma-reduction interventions in Myanmar.


Assuntos
Infecções por HIV , Infecções por HIV/diagnóstico , Humanos , Mianmar , Psicometria , Reprodutibilidade dos Testes , Estigma Social , Inquéritos e Questionários
13.
BMC Oral Health ; 20(1): 194, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641033

RESUMO

BACKGROUND: An increase in the number of elderly edentulous patients likely leads to a greater demand for dentures and denture adhesives. As denture adhesives have both positive and negative features, dentists need to know the types of denture adhesive users to be able to provide instruction to denture wearers on how to use denture adhesives effectively. This study aims to examine the utilization of denture adhesives and associated factors. METHODS: Seven closed-ended questionnaires were developed for a web-based survey. After that, Fisher's exact tests were performed to determine the difference in the denture adhesive usage rate by gender, type of denture, last dental visit, and smoking status. A multivariate-adjusted logistic regression analysis was performed with denture adhesive use or non-use as the dependent variable and the other items as independent variables. Next, Fisher's exact tests and a multivariate-adjusted logistic regression analysis were performed with the type of denture adhesives as the dependent variable in the same way. Statistical analyses were performed for all denture wearers, complete denture wearers, and partial denture wearers. The level of statistical significance was set at p = 0.05. RESULTS: A total of 1470 denture wearers in Japan participated in this study. Of these, 318 used denture adhesives, while 212 (66.7%) used cream; 74 (23.3%) used home liner; 25 (7.9%) used powder; four (1.3%) used sheets; and three (0.9%) used several types. The Fisher's exact tests revealed that the ratios of using denture adhesives were significantly higher for complete denture wearers (p < 0.001), last dental visit over 1 year (p = 0.005), and smokers (p = 0.005). For partial denture wearers, the ratio was significantly higher in smokers (p = 0.262). The multivariate adjusted logistic regression revealed that denture adhesive use or non-use were significantly associated with the type of denture and smoking status in all denture wearers, and just smoking status in partial denture wearers. There were no significant results about the type of denture adhesive selection. CONCLUSIONS: From all denture wearers, complete denture wearers and smokers are more likely to use denture adhesives. In addition, smokers significantly use denture adhesives if they are partial denture wearers.


Assuntos
Adesivos/uso terapêutico , Cimentos Dentários , Retenção de Dentadura/estatística & dados numéricos , Prótese Total , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Saúde Bucal , Qualidade de Vida , Inquéritos e Questionários
14.
Case Rep Oncol ; 12(2): 639-643, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31543781

RESUMO

Merkel cell carcinoma is a rare but aggressive skin cancer. Response to chemotherapy is not durable but avelumab, an anti-PD-L1 inhibitor, showed promising ongoing response in a phase II trial. Checkpoint inhibitors including avelumab are known to cause overactivation of the immune system, leading to immune-related adverse events (irAE). We describe the first reported case of hypercalcaemia secondary to reactivation of sarcoidosis in a patient with metastatic Merkel cell carcinoma on avelumab. Hypercalcaemia was managed with corticosteroids to full resolution and avelumab therapy was safely continued.

15.
Respir Med Case Rep ; 19: 80-2, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27536550

RESUMO

An otherwise healthy male abbatoir worker presented to his general practitioner with acute hypoxemia due to bronchopneumonia. His only occupational exposure was cleaning cow carcasses being prepared for consumption. Blood cultures were eventually positive for Pasteurella multocida. To our knowledge, this is the first reported case of Pasteurella multocida pneumonia in an abattoir worker, and illustrates the importance of considering this infection in patients with animal exposures.

16.
Telemed J E Health ; 22(3): 183-90, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26288147

RESUMO

BACKGROUND: U.S. military families are experiencing high obesity rates similar to the civilian population. The Department of Defense's Military Health System (MHS) is one of the largest healthcare providers in the United States, serving approximately 9.2 million active duty service members, retirees, spouses, and children. The annual cost to the MHS for morbidities associated with being overweight exceeds $1 billion. The preschool age has been suggested as an opportune time to intervene for the prevention of obesity. Thus, this study investigated the current level of technology usage by military service member families and assessed their needs and interests in health/nutrition information. This needs assessment is crucial for researchers/educators to design further studies and intervention programs for obesity prevention in military families with young children. MATERIALS AND METHODS: In total, 288 military parents (233 Army and 55 Air Force) at two military bases whose children were enrolled in military childcare centers in the southwestern United States participated in a Technology Usage in Military Family (TUMF) survey in 2013. RESULTS AND CONCLUSIONS: Overall, both bases presented similar technology usage patterns in terms of computer and mobile device usage on the Internet. Air Force base parents had a slightly higher knowledge level of nutrition/health information than Army base parents. The TUMF survey suggested practical ways such as mobile applications/Web sites, social networks, games, etc., that health educators can use to disseminate nutrition/health information for obesity prevention among military families with young children.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Militares/estatística & dados numéricos , Pais/psicologia , Obesidade Infantil/prevenção & controle , Inquéritos e Questionários , Telemedicina/estatística & dados numéricos , Adolescente , Adulto , Criança , Computadores/estatística & dados numéricos , Feminino , Humanos , Incidência , Disseminação de Informação , Masculino , Obesidade Infantil/epidemiologia , Estados Unidos , Adulto Jovem
17.
Huan Jing Ke Xue ; 29(4): 1119-23, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18637372

RESUMO

The characteristics and leaching behavior of heavy metals in fly ash, sampled from 4 MSWI plants, were investigated in this study. The results indicated that the main elements of fly ash were Si, Ca, Al, Cl, and heavy metals such as lead, zinc, copper, chromium and cadmium were enriched in fly ash which had great environmental risk. However, co-disposal of fly ash in sanitary landfill was an available and practical resolvent. For disposal security, the leaching procedure of toxicity basing on co-disposal scenario, which had been implemented from 1st May 2007, had increased the acidity of leachant to 0.3 mol x L(-1). The experiments of chelating stabilization technology using dithiocarbamate were carried out for MSWI fly ash treatment. The results indicated that heavy metals in fly ash were fixed by DTC in manner of chelating reaction. With the amount of additive reaching 3% (mass fraction), the concentrations of heavy metals in leachate of these fly ash samples could meet the demand of co-disposal in sanitary landfill.


Assuntos
Carbono/química , Cidades , Incineração/métodos , Metais Pesados/química , Material Particulado/química , Eliminação de Resíduos/métodos , Quelantes/química , Cinza de Carvão , Poluição Ambiental/análise , Poluição Ambiental/prevenção & controle , Tiocarbamatos/química
18.
Huan Jing Ke Xue ; 28(12): 2867-72, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18290452

RESUMO

The behavior of acidity neutralization capacity (ANC) depletion and change of pH values in leachate from two representative samples were investigated with test of general acidity neutralization capacity (GANC) and multistage extraction test (MET). The results indicated that low estimation of potential environmental risk would be conduced with low depletion of ANC and high pH values of leachate in such actual batch test. Comparing the results of GANC with that of MET, neutralization and wash-out process would take place at the same way under the flow-through scenarios of co-disposal, and there is one-third alkaline components reacting in the neutralization process. With simulative calculation basing on reasonable hypothesis of parameter in sanitary landfill, the extraction procedure for leaching toxicity of fly ash from MSWI under codisposal scenario was proposed, using leachant of 0.3 mol x L(-1) HAc solution and L/S =20. This procedure would definitely provide disposal of MSWI fly ash in China with reliable safeguard and effective management.


Assuntos
Monitoramento Ambiental/métodos , Incineração , Eliminação de Resíduos/métodos , Poluentes do Solo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Carbono , China , Cinza de Carvão , Poluição Ambiental/prevenção & controle , Concentração de Íons de Hidrogênio , Material Particulado , Reprodutibilidade dos Testes , Solubilidade
19.
Huan Jing Ke Xue ; 28(11): 2646-50, 2007 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-18290498

RESUMO

The characteristics and leaching behavior of heavy metals in fly ash, sampled from 12 MSWI plants in China, were investigated. The results indicated that the main elements of fly ash were Si, Ca, Al, Fe, K, Na, Cl, and the total fraction of heavy metals was in the range of 0.5 % - 3.0% with the exception of one sample. Therefore MSWI fly ash must be controlled as hazardous materials because of its potential environmental risk. The leaching ratios of heavy metals in fly ash were low to some extent according to the results of batch tests such as Toxicity Characteristic Leaching Procedure (TCLP) of U. S. EPA and GB 5086.1-1997. The notable variance of TCLP and GB 5086 evaluating the same sample was due to the obvious difference of pH values in leachate. The result of general acidity neutralization capacity (GANC) showed that the leaching behavior of heavy metals in fly ash were controlled by the final pH of leachate, which was determined by the inter-reaction of alkaline in fly ash and acidity of leachant. The end points of equilibrium in batch test and flow-through test had great difference based on the analysis of these procedures. It is of significant meaning to build a batch procedure basing on the disposal scenarios and characteristics of fly ash for the purpose of adequate risk assessment and management.


Assuntos
Poluentes Ambientais/análise , Substâncias Perigosas/análise , Incineração , Metais Pesados/análise , Eliminação de Resíduos/métodos , Carbono/química , China , Cinza de Carvão , Concentração de Íons de Hidrogênio , Material Particulado/química , Medição de Risco , Poluentes do Solo/análise , Solubilidade , Poluentes Químicos da Água/análise
20.
Huan Jing Ke Xue ; 26(3): 172-5, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-16124493

RESUMO

The distribution and characters of heavy metals from municipal solid waste incinerator fly ash was studied in East China. The result indicate that heavy metals in fly ash were mainly distributed in fine particles. The heavy metals including Cd, Pb, Mg, and Cu could migrate easily from fly ash while Ag and Sn would be more stable. The metal mobility changed with the pH level. For environmentally important metals such as Cd, Co, Cu, Mn, Ni, Pb, and Zn, the increase in mobility due to the decrease in pH was more pronounced and significant than for other elements, while Cr and As with the opposite condition.


Assuntos
Poluentes Atmosféricos/análise , Carbono/análise , Incineração , Metais Pesados/análise , Material Particulado/análise , Eliminação de Resíduos/métodos , Cádmio/análise , Cinza de Carvão , Cobalto/análise , Chumbo/análise
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