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1.
Occup Med (Lond) ; 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38078549

RESUMEN

BACKGROUND: An outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with an attack rate of 55% (22/40 workers) occurred at a public-facing office in England from August to September 2021. Published evidence regarding outbreaks in office workplaces remains limited. AIMS: To describe an investigation of workplace- and worker-related risk factors following an outbreak of SARS-CoV-2 in a public-facing office. METHODS: The COVID-19 (coronavirus disease 2019) Outbreak Investigation to Understand Transmission (COVID-OUT) study undertook an investigation of the outbreak. This included surface sampling, occupational environmental assessment, molecular and serological testing of workers, and detailed questionnaires. RESULTS: Despite existing COVID-19 control measures, surface sampling conducted during a self-imposed 2-week temporary office closure identified viral contamination (10/60 samples, 17% positive), particularly in a small, shared security office (6/9, 67% positive) and on a window handle in one open-plan office. Targeted enhanced cleaning was, therefore, undertaken before the office reopened. Repeat surface sampling after this identified only one positive (2%) sample. Ventilation was deemed adequate using carbon dioxide monitoring (typically ≤1000 ppm). Twelve workers (30%) responded to the COVID-OUT questionnaire, and all had been vaccinated with two doses. One-third of respondents (4/12) reported direct physical or close contact with members of the public; of these, 75% (3/4) reported a divider/screen between themselves and members of the public. CONCLUSIONS: The results highlight the potential utility of surface sampling to identify SARS-CoV-2 control deficiencies and the importance of evolving, site-specific risk assessments with layered COVID-19 mitigation strategies.

2.
Community Ment Health J ; 59(6): 1083-1096, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36695952

RESUMEN

Scholars suggest that marginalized people in non-urban areas experience higher distress levels and fewer psychosocial resources than in urban areas. Researchers have yet to test whether precise proximity to urban centers is associated with mental health for marginalized populations. We recruited 1733 people who reported living in 45 different countries. Participants entered their home locations and completed measures of anxiety, depression, social support, and resilience. Regression and thematic analyses were used to determine what role distance from legislative and urban centers may play in mental health when marginalized people were disaggregated. Greater distance from legislative center predicted higher anxiety and resilience. Greater distance from urban center also predicted more resilience. Thematic analyses yielded five categories (e.g., safety, connection) that further illustrated the impact of geographic location on health. Implications for community mental health are discussed including the need to better understand and further expand resilience in rural areas.


Asunto(s)
Salud Mental , Población Rural , Humanos , Población Urbana , Ansiedad/epidemiología , Ansiedad/psicología , Trastornos de Ansiedad
3.
Environ Monit Assess ; 192(8): 514, 2020 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32666298

RESUMEN

Public health monitoring of Community Water Fluoridation (CWF) schemes requires estimates of exposure to fluoride in public water supplies (PWS). We aimed to use routine data to estimate population exposure to PWS-fluoride in England and to determine whether PWS-fluoride exposure from 2005 to 2015 could be used as a proxy for exposure for 1995-2004, when fluoride concentration data that could be linked to population health data were unavailable. We calculated annual mean water supply zone PWS-fluoride concentrations from monitoring data for 1995-2015, stratified by fluoridation scheme-flagging. We allocated annual 2005-2015 mean PWS-fluoride concentrations to small area boundaries to describe population exposure within five concentration categories (< 0.1 to ≥ 0.7 mg/L). We compared zone-level 1995-2004 and 2005-2015 mean PWS-fluoride concentrations using Spearman correlation. Most (72%) of the population received PWS with < 0.2 mg/L fluoride and 10% with ≥ 0.7 mg/L. Fluoride concentrations in 1995-2004 and 2005-2015 were similar (median 0.11 mg/L (lower quartile-upper quartile (LQ-UQ) 0.06-0.17) and 0.11 mg/L (LQ-UQ 0.07-0.17), respectively) and highly correlated (coefficient 0.93) if un-fluoridated but differed (1995-2004 median 0.78 mg/L (LQ-UQ 0.59-0.92); 2005-2015 0.84 mg/L (LQ-UQ 0.72-0.95)) and correlated weakly (coefficient 0.31) if fluoridated. Fluoride concentrations in 2005-2015 approximate those in 1995-2004 but with a greater risk of misclassification in fluoridation schemes.


Asunto(s)
Monitoreo del Ambiente , Fluoruros/análisis , Inglaterra , Fluoruración , Abastecimiento de Agua
4.
J R Army Med Corps ; 163(1): 2-6, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27177574

RESUMEN

This paper describes the development of the UK military's Ebola Virus Disease Treatment Unit (EVD TU) that was deployed to Sierra Leone as part of the UK response to the West African Ebola virus disease (EVD) epidemic in 2014 and 2015. It highlights specific challenges faced within this unique Field Hospital environment. The military EVD TU was initially established to provide confidence to international healthcare workers coming to Sierra Leone to assist in the international response to the EVD epidemic and formed a key part of the action plan by the UK's Department for International Development. It was designed and staffed to provide a high level of care to those admitted with suspected or confirmed EVD and was prepared to admit the first patient within 6 weeks of the original activation order by the Ministry of Defence. This article outlines the main hazards perceived at the outset of the operation and the methods used to mitigate the risk to the healthcare workers at the EVD TU. The article examines the mechanisms that enabled the hospital to respond positively to challenges that emerged during the deployment, while simultaneously reducing the risk to the healthcare workers involved in care delivery.


Asunto(s)
Atención a la Salud/organización & administración , Epidemias , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/terapia , Unidades Móviles de Salud/organización & administración , Fiebre Hemorrágica Ebola/diagnóstico , Humanos , Sierra Leona/epidemiología , Reino Unido
5.
Environ Geochem Health ; 38(6): 1313-1332, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26810082

RESUMEN

Tap water from 497 properties using private water supplies, in an area of metalliferous and arsenic mineralisation (Cornwall, UK), was measured to assess the extent of compliance with chemical drinking water quality standards, and how this is influenced by householder water treatment decisions. The proportion of analyses exceeding water quality standards were high, with 65 % of tap water samples exceeding one or more chemical standards. The highest exceedances for health-based standards were nitrate (11 %) and arsenic (5 %). Arsenic had a maximum observed concentration of 440 µg/L. Exceedances were also high for pH (47 %), manganese (12 %) and aluminium (7 %), for which standards are set primarily on aesthetic grounds. However, the highest observed concentrations of manganese and aluminium also exceeded relevant health-based guidelines. Significant reductions in concentrations of aluminium, cadmium, copper, lead and/or nickel were found in tap waters where households were successfully treating low-pH groundwaters, and similar adventitious results were found for arsenic and nickel where treatment was installed for iron and/or manganese removal, and successful treatment specifically to decrease tap water arsenic concentrations was observed at two properties where it was installed. However, 31 % of samples where pH treatment was reported had pH < 6.5 (the minimum value in the drinking water regulations), suggesting widespread problems with system maintenance. Other examples of ineffectual treatment are seen in failed responses post-treatment, including for nitrate. This demonstrates that even where the tap waters are considered to be treated, they may still fail one or more drinking water quality standards. We find that the degree of drinking water standard exceedances warrant further work to understand environmental controls and the location of high concentrations. We also found that residents were more willing to accept drinking water with high metal (iron and manganese) concentrations than international guidelines assume. These findings point to the need for regulators to reinforce the guidance on drinking water quality standards to private water supply users, and the benefits to long-term health of complying with these, even in areas where treated mains water is widely available.


Asunto(s)
Agua Potable/química , Purificación del Agua/métodos , Arsénico/análisis , Inglaterra , Monitoreo del Ambiente , Agua Subterránea/análisis , Concentración de Iones de Hidrógeno , Metales/análisis , Nitratos/análisis , Contaminantes Químicos del Agua/análisis , Calidad del Agua/normas , Abastecimiento de Agua/métodos
6.
J R Army Med Corps ; 162(3): 163-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27231284

RESUMEN

We discuss the training methodology developed and utilised to prepare UK military medical teams to establish an Ebola Treatment Centre in Sierra Leone. We highlight the process of identifying and mitigating nosocomial risk in the Pre-Deployment Training process, encompassing the challenges of developing, training and assuring a capability at pace, which deployed to deliver high quality clinical care to patients with Ebola Virus Disease.


Asunto(s)
Brotes de Enfermedades , Personal de Salud/educación , Fiebre Hemorrágica Ebola/epidemiología , Cooperación Internacional , Personal Militar/educación , Grupo de Atención al Paciente , Equipo de Protección Personal , África Occidental/epidemiología , Infección Hospitalaria/prevención & control , Fiebre Hemorrágica Ebola/prevención & control , Fiebre Hemorrágica Ebola/terapia , Fiebre Hemorrágica Ebola/transmisión , Humanos , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , Liberia/epidemiología , Misiones Médicas , Modelos Educacionales , Garantía de la Calidad de Atención de Salud , Sierra Leona/epidemiología , Reino Unido , Organización Mundial de la Salud
7.
J R Army Med Corps ; 160(2): 180-2, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24607484

RESUMEN

Nepalese Gurkha soldiers are recruited from a country endemic for a number of infectious diseases, including tuberculosis and gastrointestinal parasites. This article describes a prospective cohort study which investigated screening strategies for these infections among Gurkha recruits arriving in the UK to begin basic training. Several recommendations were made as a result of the study which were supported for early implementation and subsequently fully adopted. Military screening and treatment policies have been directly influenced by this research which also has translational application to similar migrant civilian populations.


Asunto(s)
Helmintiasis/diagnóstico , Tuberculosis Latente/diagnóstico , Tamizaje Masivo/métodos , Personal Militar , Heces/parasitología , Enfermedades Gastrointestinales/diagnóstico , Humanos , Ensayos de Liberación de Interferón gamma , Nepal , Estudios Prospectivos
8.
Sci Data ; 11(1): 113, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263407

RESUMEN

Wastewater treatment plants (WWTPs) are large electricity and natural gas consumers with untapped potential to recover carbon-neutral biogas and provide energy services for the grid. Techno-economic analysis of emerging energy recovery and management technologies is critical to understanding their commercial viability, but quantifying their energy cost savings potential is stymied by a lack of well curated, nationally representative electricity and natural gas tariff data. We present a dataset of electricity tariffs for the 100 largest WWTPs in the Clean Watershed Needs Survey (CWNS) and natural gas tariffs for the 54 of 100 WWTPs with on-site cogeneration. We manually collected tariffs from each utility's website and implemented data checks to ensure their validity. The dataset includes facility metadata, electricity tariffs, and natural gas tariffs (where cogeneration is present). Tariffs are current as of November 2021. We provide code for technical validation along with a sample simulation.

9.
J Voice ; 2023 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-36941164

RESUMEN

OBJECTIVE: To assess the recent literature for voice acoustic data values reported for individuals without voice disorder through the lifespan as a means to develop an updated normative acoustic data resource for children and adults. METHODS: A scoping review was conducted using the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) Checklist. English language, full-text publications were identified through Medline (EBSCO & OVID), PubMed, APA PsycINFO, Web of Science, Google Scholar, and ProQuest Theses and Dissertations Global. RESULTS: A total of 903 sources were retrieved; of these 510 were duplicates. Abstracts of 393 were screened, with 68 full-text review. From the eligible studies, citation review yielded 51 additional resources. Twenty-eight sources were included for data extraction. For the normative acoustic data extracted for males and females across the lifespan, lower fundamental frequency for adult females was observed and few studies collected semitone range, sound level range, or frequency range. Data extraction also indicated a predominately gender binary reporting of acoustic measures with few studies reporting gender identity, race, or ethnicity as variables of interest. CONCLUSIONS: The scoping review yielded updated acoustic normative data that is of value for clinicians and researchers who rely on this normative data to make determinations about vocal function. The limited availability of acoustic data by gender, race, and ethnicity creates barriers for generalization of these normative values across all patients, clients, and research volunteers.

10.
Travel Med Infect Dis ; 52: 102540, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36587754

RESUMEN

With the emergence of SARS-CoV-2 and now monkeypox, the UK Defence Medical Services have been required to provide rapid advice in the management of patients with airborne high consequence infectious diseases (A-HCID). The Defence Public Health Network (DPHN) cadre, consisting of closely aligned uniformed and civilian public health specialists have worked at pace to provide evidence-based recommendations on the clinical management, public health response and policy for monkeypox, with military medicine and pathology clinicians (primarily infectious disease physicians and medical microbiologists). Military environments can be complicated and nuanced requiring specialist input and advice to non-specialists as well as unit commanders both in the UK and overseas. DPHN and military infection clinicians have close links with the UK National Health Service (NHS) and the UK Health Security Agency (UKHSA), allowing for a dynamic two-way relationship that encompasses patient management, public health response, research and development of both UK military and national guidelines. This is further demonstrated with the Royal Air Force (RAF) Air Transport Isolator (ATI) capability, provided by Defence to support the UK Government and UKHSA. Military infectious disease clinicians are also embedded within NHS A-HCID units. In this manuscript we provide examples of the close interdisciplinary working of the DPHN and Defence clinicians in managing military monkeypox patients, co-ordinating the public health response, advising the Command and developing monkeypox policy for Defence through cross-government partnership. We also highlight the co-operation between civilian and military medical authorities in managing the current outbreak.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Medicina Militar , Personal Militar , Mpox , Humanos , Mpox/epidemiología , Medicina Estatal , COVID-19/epidemiología , SARS-CoV-2 , Brotes de Enfermedades , Reino Unido/epidemiología , Enfermedades Transmisibles/epidemiología
11.
Water Sci Technol ; 63(11): 2612-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22049756

RESUMEN

The presence of arsenic and heavy metals in drinking water sources poses a serious health risk due to chronic toxicological effects. Constructed wetlands have the potential to remove arsenic and heavy metals, but little is known about pollutant removal efficiency and reliability of wetlands for this task. This lab-scale study investigated the use of vertical subsurface flow constructed wetlands for removing arsenic, boron, copper, zinc, iron and manganese from synthetic wastewater. Gravel, limestone, zeolite and cocopeat were employed as wetland media. Conventional gravel media only showed limited capability in removing arsenic, iron, copper and zinc; and it showed virtually no capability in removing manganese and boron. In contrast, alternative wetland media: cocopeat, zeolite and limestone, demonstrated significant efficiencies--in terms of percentage removal and mass rate per m3 of wetland volume--for removing arsenic, iron, manganese, copper and zinc; their ability to remove boron, in terms of mass removal rate, was also higher than that of the gravel media. The overall results demonstrated the potential of using vertical flow wetlands to remove arsenic and metals from contaminated water, having cocopeat, zeolite or limestone as supporting media.


Asunto(s)
Arsénico/química , Boro/química , Metales Pesados/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Humedales , Eliminación de Residuos Líquidos/métodos
12.
Water Sci Technol ; 64(9): 1913-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22020487

RESUMEN

Biofiltration systems are widely used to mitigate the impacts of stormwater on receiving waters, however their long-term capacity to retain heavy metals has not previously been assessed. Accelerated-dosing laboratory experiments were used to assess the likelihood of breakthrough occurring for three different types of soil-based filter media that are commonly used in stormwater biofilters. In all cases, breakthrough of zinc (Zn) was observed, but not of cadmium (Cd), copper (Cu) and lead (Pb). If biofiltration systems are sized so that they are large relative to their catchment (at least 2-3% of its area) or have a deep filter layer (at least 0.5 m deep), then breakthrough will not occur for at least ten years and probably longer. However, after the equivalent of 12-15 years of operation, Cd, Cu and Zn had accumulated in the filter media to levels that exceeded human health and/or ecological guidelines. Further, depending on the design, it is possible that spent filter media may be classified as contaminated soil and thus require special disposal.


Asunto(s)
Tormentas Ciclónicas , Filtración/métodos , Metales Pesados/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Clima , Lluvia , Factores de Tiempo , Contaminación del Agua/análisis
13.
Water Sci Technol ; 64(8): 1692-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22335113

RESUMEN

Pervious pavements are an effective stormwater treatment technology. However, their performance under variable drying and wetting conditions have yet to be tested, particularly under a continuous time scale. This paper reports on the clogging behaviour and pollutant removal efficiency of three pervious pavement types over 26 accelerated years. These pavements were monolithic porous asphalt (PA), Permapave (PP) and modular Hydrapave (HP). Over a cycle of 13 days, the period of which was equivalent to the average annual Brisbane, Australia rainfall (1,200 mm), the pavements were randomly dosed with four different flows. Drying events of 3 h duration were simulated during each flow. Inflow and outflow samples were collected and analysed for Total Suspended Solids (TSS), Total Phosphorus (TP) and Total Nitrogen (TN). To evaluate the rate of clogging, a 1 in 5 year Brisbane storm event was simulated in the 6th, 8th, 12th, 16th, 20th and 24th week. Under normal dosing conditions, none of the pavements showed signs of clogging even after 15 years. However, under storm conditions, both PA and HP started to clog after 12 years, while PP showed no signs of clogging after 26 years. The drying and various flow events showed no effects in TSS removal, with all systems achieving a removal of approximately 100%. The average TP removal was 20% for all flows except for low flow, which had a significant amount of leaching over time. Leaching from TN was also observed during all flows except high flow. The TSS, TP and TN results observed during storm events were similar to that of high flow.


Asunto(s)
Materiales de Construcción , Movimientos del Agua , Agua/química , Monitoreo del Ambiente/métodos , Lluvia , Factores de Tiempo , Transportes , Contaminantes Químicos del Agua
14.
Eur Respir J ; 36(2): 249-54, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20032017

RESUMEN

Inconsistent effects of gas cooking on lung function have been reported. In a previous study from Austria, we demonstrated a significant, though small, reduction of lung function parameters in children living in homes with gas stoves. We used a larger international database to check if this finding can be generalised. To study the relative impact of cooking with gas on lung function parameters of primary school children in a wide range of geographical settings, we analysed flow and volume data of approximately 24,000 children (aged 6-12 yrs) from nine countries in Europe and North America. Exposure information was obtained by comparable questionnaires and spirometry according to an American Thoracic Society/European Respiratory Society protocol. Linear regressions were used, controlling for individual risk factors and study area. Heterogeneity between study-specific results and mean effects were estimated using meta-analytical tools. On average, gas cooking reduced lung function parameters. Overall effects were small (-0.1-0.7%) and only significant for forced vital capacity and forced expiratory volume in 1 s. There was some indication that allergic children were more affected by gas cooking. Under current housing conditions, gas cooking is associated with only small reductions in lung function.


Asunto(s)
Manipulación de Alimentos , Combustibles Fósiles/efectos adversos , Contaminantes Atmosféricos , Contaminación del Aire Interior , Niño , Exposición a Riesgos Ambientales , Femenino , Gases , Humanos , Pulmón/patología , Pulmón/fisiopatología , Masculino , Dióxido de Nitrógeno/química , Análisis de Regresión , Trastornos Respiratorios/etiología , Espirometría/métodos
15.
Water Sci Technol ; 62(4): 837-43, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20729586

RESUMEN

The complex nature of pollutant accumulation and washoff, along with high temporal and spatial variations, pose challenges for the development and establishment of accurate and reliable models of the pollution generation process in urban environments. Therefore, the search for reliable stormwater quality models remains an important area of research. Model calibration and sensitivity analysis of such models are essential in order to evaluate model performance; it is very unlikely that non-calibrated models will lead to reasonable results. This paper reports on the testing of three models which aim to represent pollutant generation from urban catchments. Assessment of the models was undertaken using a simplified Monte Carlo Markov Chain (MCMC) method. Results are presented in terms of performance, sensitivity to the parameters and correlation between these parameters. In general, it was suggested that the tested models poorly represent reality and result in a high level of uncertainty. The conclusions provide useful information for the improvement of existing models and insights for the development of new model formulations.


Asunto(s)
Tormentas Ciclónicas , Vivienda , Lluvia , Abastecimiento de Agua , Agua/normas , Teorema de Bayes , Calibración , Vivienda/normas , Humanos , Modelos Teóricos , Salud Urbana , Contaminantes del Agua/análisis
16.
Science ; 185(4148): 360-1, 1974 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-4834366

RESUMEN

Fungal extracts that precipitate with human C-reactive protein caused immediate erythema on subdermal injection into marine flatfish. Only species with calcium-dependent serum precipitins to these fungi showed skin reactions. Immediate hypersensitivity in a nonreactive species could be induced after injection with serum from reactive species. The transferable serum factor (or factors) was heat sensitive.


Asunto(s)
Antígenos Fúngicos , Peces/inmunología , Hipersensibilidad Inmediata/inmunología , Alérgenos , Animales , Anticuerpos Antifúngicos , Proteína C-Reactiva , Reacciones Cruzadas , Hongos/inmunología , Calor , Inmunización Pasiva , Inmunoglobulina E , Anafilaxis Cutánea Pasiva , Precipitinas , Pruebas Cutáneas , Especificidad de la Especie
17.
Science ; 228(4697): 291-7, 1985 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-3838593

RESUMEN

A general method for modifying eukaryotic genes by site-specific mutagenesis and subsequent expression in mammalian cells was developed to study the relation between structure and function of the proteolytic enzyme trypsin. Glycine residues at positions 216 and 226 in the binding cavity of trypsin were replaced by alanine residues, resulting in three trypsin mutants. Computer graphic analysis suggested that these substitutions would differentially affect arginine and lysine substrate binding of the enzyme. Although the mutant enzymes were reduced in catalytic rate, they showed enhanced substrate specificity relative to the native enzyme. This increased specificity was achieved by the unexpected differential effects on the catalytic activity toward arginine and lysine substrates. Mutants containing alanine at position 226 exhibited an altered conformation that may be converted to a trypsin-like structure upon binding of a substrate analog.


Asunto(s)
Tripsina/genética , Secuencia de Aminoácidos , Animales , ADN/genética , Electroforesis , Mutación , Ratas , Especificidad por Sustrato , Tripsina/biosíntesis , Tripsina/metabolismo , Tripsinógeno/metabolismo
18.
Ann Occup Hyg ; 53(1): 83-97, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19131404

RESUMEN

OBJECTIVES: This study describes exposures to military veterans who participated between 1941 and 1989 in British research at Porton Down on the effects of exposure to chemical warfare agents and to defences against those agents. The study is part of a programme of epidemiological research initiated in response to service veterans' concerns about possible long-term health effects of their participation. METHODS: All entries in 97 books held in the Porton Down historical experimental archive covering the years 1939-1989 were reviewed. For tests between April 1941 and December 1989, data were abstracted on chemicals used, with additional detail abstracted for tests involving vesicants and nerve agents. For tests recorded during 1939-1941, similar data were abstracted for a representative sample of tests. RESULTS: Historical data were abstracted for 17 303 veterans included in the cohort study of 18,276 servicemen who took part in tests at Porton Down between 1941 and 1989. The median number of days per veteran on which tests were carried out was 2 days. The median difference between the last and first day of testing was 4 days. A large number of chemicals were tested over this period (n = 492). The type of chemical tested varied over time. Exposures were often modified by respirator use or use of protective clothing or protective equipment. It was possible to assign a quantitative measure of cumulative exposure to 73% of veterans exposed to the vesicant sulphur mustard--3491 (34%) of exposed veterans had cumulative exposures > or =10.63 mg and for 70% of veterans exposed to the nerve agent sarin--658 (29%) of exposed veterans had cumulative exposures > or =15.0 mg min m(-3). Ninety-three per cent of veterans exposed to sulphur mustard were classified to a semi-quantitative scale of dermal effect--3771 (37%) had a vesicle or necrosed area, and 69% of veterans exposed to sarin could be categorized by change in blood cholinesterase activity--1033 (31%) had a depression in cholinesterase activity of > or =30%. CONCLUSIONS: The experimental archive at Porton Down has proved to be a rich source of data on tests conducted between 1941 and 1989. It has been possible to categorize most veterans according to date of test, chemical group, chemical, type of protection and, for certain chemicals, level of exposure and/or degree of acute toxicity. These categorizations have been used to assign veterans to exposure groups for epidemiological analysis.


Asunto(s)
Sustancias para la Guerra Química/toxicidad , Exposición a Riesgos Ambientales/análisis , Experimentación Humana , Sustancias para la Guerra Química/análisis , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Estudios de Factibilidad , Humanos , Masculino , Veteranos/estadística & datos numéricos
19.
Water Sci Technol ; 59(8): 1567-76, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19403970

RESUMEN

The pollutant removal performance of three separate stormwater biofiltration systems in two different climates was assessed. At one of the sites, rain events were simulated, while actual runoff events were monitored at the other two sites. In all cases, concentrations of total suspended solids (TSS), copper, lead and zinc were effectively and reliably reduced, despite variations in inflow concentrations. Two biofiltration systems also effectively reduced phosphorus concentrations, however the third system discharged elevated phosphorus concentrations relative to inflow; this is attributed to poor specification of filter media properties. Effluent nitrogen concentrations were more variable at all sites and ranged from being substantially lower to considerably higher than inflow concentrations. Flow was also measured at two sites, where it was determined that volumetric reductions in runoff further improved pollutant removal. TSS and heavy metals will be reliably removed by a wide range of soil-based filter media, as will phopshorus, as long as the phosphorus content of the filter media is low. However, nitrogen removal remains a challenge because it is easily transformed to soluble forms and is influenced by wetting and drying. These results are essentially consistent with related laboratory studies.


Asunto(s)
Filtración/métodos , Desarrollo de la Planta , Lluvia , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Australia , Cyperaceae , Melaleuca , Metales Pesados/análisis , Nitrógeno/análisis , Fósforo/análisis
20.
Water Sci Technol ; 60(3): 717-25, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19657167

RESUMEN

Uncertainty is intrinsic to all monitoring programs and all models. It cannot realistically be eliminated, but it is necessary to understand the sources of uncertainty, and their consequences on models and decisions. The aim of this paper is to evaluate uncertainty in a flow and water quality stormwater model, due to the model parameters and the availability of data for calibration and validation of the flow model. The MUSIC model, widely used in Australian stormwater practice, has been investigated. Frequentist and Bayesian methods were used for calibration and sensitivity analysis, respectively. It was found that out of 13 calibration parameters of the rainfall/runoff model, only two matter (the model results were not sensitive to the other 11). This suggests that the model can be simplified without losing its accuracy. The evaluation of the water quality models proved to be much more difficult. For the specific catchment and model tested, we argue that for rainfall/runoff, 6 months of data for calibration and 6 months of data for validation are required to produce reliable predictions. Further work is needed to make similar recommendations for modelling water quality.


Asunto(s)
Modelos Teóricos , Lluvia , Incertidumbre , Movimientos del Agua , Agua/normas , Australia , Calibración , Reproducibilidad de los Resultados
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