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1.
Environ Geochem Health ; 45(4): 1165-1171, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35044549

RESUMO

When the SEGH international board released a short editorial paper back in 2019, we described an aim to increase the membership offering, whilst improving the diversity of input regionally, by scientific discipline and to ensure greater and more regular contact across the regions from 2020 onwards. Wider aspirations described in 2019 (Watts et al. 2019) are discussed within this short communication at the end of 2021 to evaluate progress made. In particular, how the SEGH community adapted to the unprecedented circumstances that have challenged each and every one of us throughout the COVID-19 pandemic since early 2020 and are likely to influence our activities for the foreseeable future.


Assuntos
Saúde Ambiental , Ciência Ambiental , Sociedades , Humanos , COVID-19/epidemiologia , Pandemias
2.
Environ Geochem Health ; 42(4): 1167-1195, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31346854

RESUMO

Kumba, the largest city in the Southwest Region of Cameroon, is characterized by the prevalence of waterborne diseases due to ingestion of contaminated water. Sixty-four water samples were collected from different sources including pipe-borne (PW), surface/stream (SW) and groundwater (HDW) sources as well as the catchment area (CW) in Kumba metropolis. These water samples were analyzed for physicochemical and microbiological parameters and the results compared with international standards. The results of physiochemical parameters showed that the water samples were mildly acidic, not saline and soft. The levels of some trace elements (Al, Fe, As, Cd, Co, Cu, Fe, Mn, Pb) in some water samples were higher than permissible limits. Water Quality Index, Contamination Index (Cd) and Trace Element Toxicity Index were used to evaluate the water samples. Results showed that most of the water sources are poor and unsafe for consumption due to high concentrations of Al, Fe, Mn and Pb. Microbiological parameters revealed that 74% of the water samples are in the class of high risk to grossly polluted. Pollution associated with the catchment area was probably the main factor controlling the quality of pipe-borne water, while that of the surface and groundwater may be attributed to geogenic and anthropogenic sources including unlined pit latrines. Water sources, especially those ingested by humans in Kumba, should be properly managed including regular treatment so as to protect the health of humans and improve the quality of life.


Assuntos
Água Potável/análise , Água Potável/microbiologia , Poluentes Químicos da Água/análise , Camarões , Água Potável/química , Monitoramento Ambiental/métodos , Contaminação de Alimentos/análise , Água Subterrânea/análise , Água Subterrânea/química , Água Subterrânea/microbiologia , Humanos , Metais Pesados/análise , Análise Multivariada , Saúde Pública , Medição de Risco , Rios , Microbiologia da Água , Qualidade da Água
3.
Sci Total Environ ; 500-501: 199-210, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25217995

RESUMO

Micronutrient deficiency affects over 4.5 billion people worldwide, the majority in developing countries. Deficiencies of iron (and associated anaemia) and zinc in pregnancy are associated with complications, maternal and neonatal mortality, and developmental disorders in the foetus and growing child. We report the results of pilot study which used an interdisciplinary approach to explore environmental and sociocultural factors influencing the micronutrient status in the soil-plant-human transfer for pregnant subsistence farmers in two geographically contrasting regions of Southern Malawi. It evaluated micronutrient status in soil and the staple crop and explored the context for their transfer to pregnant women. Scientific and social science methods were used to collect data, following full sensitisation of the communities. A total of 99 participants were recruited from Chiradzulu (plateau) and Chikwawa (floodplain). Soil, maize and blood samples were collected, along with food frequency and health behaviour questionnaires and anthropological observation. Statistical analysis revealed that soil iron was significantly higher in Chiradzulu than in Chikwawa; total iron concentration is not deemed to be deficient in either area. Soil zinc was not significantly different between areas. Maize concentrations of iron and zinc were not significantly different between areas, and were not deficient relative to improved cultivars. Blood iron deficiency and associated anaemia were problematic in both areas, but more so in Chikwawa than in Chiradzulu, and zinc deficiency was similar in both areas. The study has identified a significant difference in the blood iron status of the participants of the two communities, and has shown that this difference is not accounted for by the staple crop maize. Socio-geographical factors appear to play a significant role in the micronutrient health of the populations. The findings lend support to multifaceted community intervention studies which educate communities on strategies to tackle micronutrient deficiencies.


Assuntos
Agricultura , Poluentes Ambientais/metabolismo , Ferro/metabolismo , Exposição Materna/estatística & dados numéricos , Zinco/metabolismo , Adulto , Feminino , Humanos , Malaui , Micronutrientes/metabolismo , Projetos Piloto , Gravidez , Fatores Socioeconômicos , Oligoelementos/metabolismo
4.
Environ Monit Assess ; 185(6): 5177-92, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23064851

RESUMO

The littoral drift regime along the northeastern coast of India was investigated by analyzing coastal drift indicators and shoreline changes based on multitemporal satellite images. The study of offshore turbidity patterns and quantitative estimation of suspended sediments was undertaken to understand the magnitude and direction of movement of sediment fluxes. The study revealed that: (1) the character of coastal landforms and sedimentation processes indicate that the sediment transport is bidirectional and monsoon dependent; (2) multidate, multitemporal analysis of satellite images helps to show the nature of sediment transport along the coast. The dominant net sediment transport is in a NE direction along the eastern coast of India. Finally, this assessment demonstrates the potential of remote sensing technology in understanding the coastal morphometric changes, long-term sediment transport, shoreline changes, and offshore turbidity distribution pattern and the implications for the transport of sediment-associated pollutants.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/análise , Água do Mar/química , Movimentos da Água , Índia , Tecnologia de Sensoriamento Remoto , Água do Mar/análise , Astronave
5.
J Proteomics ; 78: 159-71, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23178873

RESUMO

Pentachlorophenol (PCP) represents a critical concern worldwide due to its toxicity and recalcitrance to degradation. The capacity of Mucor plumbeus to transform PCP into several detoxification metabolites, including tetrachlorohydroquinone and several phase II conjugates, was observed by LC-HRMS. The data obtained support the degradation pathway proposed previously. PCP effects in M. plumbeus, an unsequenced species, were investigated using a proteomics approach (bidimensional gel electrophoresis followed by MALDI TOF/TOF analyses). The mycelial proteins identified in the differentially accumulated spots allowed the identification of PCP responsive proteins. The presence of PCP increased the energy demand, altered the cell wall architecture and cytoskeleton and induced a significant stress response. The latter was emphasised by the up-accumulation of protein species associated with defence mechanisms (e.g. HSP70 and cytochrome c peroxidase). Overall the data produced corroborate the capability of PCP to uncouple oxidative-phosphorylation in mitochondria. Importantly, one of the identified mycelial protein species, a NAD- and Zn-dependent ADH, is likely to be involved in PCP degradation. Amongst the fungal secretome analysed, no putative PCP degradative enzymes were detected. This work constitutes the first toxicoproteomic study involving a Zygomycota fungus and the very first concerning the effect of PCP in a fungal proteome.


Assuntos
Poluentes Ambientais/farmacologia , Proteínas Fúngicas/metabolismo , Mucor/metabolismo , Pentaclorofenol/farmacologia , Proteômica , Biotransformação/efeitos dos fármacos , Biotransformação/fisiologia , Poluentes Ambientais/metabolismo , Pentaclorofenol/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
Environ Int ; 35(1): 202-13, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18817974

RESUMO

Since many soil studies have already revealed the possible risks to human health and the environment arising from contaminated soils it is therefore crucial to preserve soil quality under current and future conditions. In the last three decades a number of countries already introduced national policies and practices for the management of contaminated sites, and in 2002, an EU Thematic Strategy for Soil Protection was proposed by the European Commission. In this paper we review and analyse several national contaminated land policy regimes already in place in order to assess common elements and to identify specific needs in the development of national soil policies. We propose a framework that combines the D-P-S-I-R structure of policy evaluation with the Source-Pathway-Receptor approach to health risk assessment to support the development of effective country specific regulatory decisions for managing contaminated land in countries where these are yet to be implemented. The framework proposed allows decision makers to effectively use available information and to identify existing data gaps. As a result it is apparent that while there are technical aspects of site characterisation, risk assessment and remediation processes that could be commonly implemented at an EU level there are certain trans-scientific aspects that require political choices and need to be customized by EU Member States.


Assuntos
Conservação dos Recursos Naturais/métodos , Poluição Ambiental/prevenção & controle , Política de Saúde , Poluentes do Solo , Europa (Continente) , Humanos
7.
Environ Pollut ; 157(2): 511-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18952333

RESUMO

The concentration of PCBs in topsoils from five European cities was assessed and the highest levels were found in Glasgow (Scotland), followed by Torino (Italy), Aveiro (Portugal), Ljubljana (Slovenia) and Uppsala (Sweden). All cities showed the presence of local sources in addition to diffuse contamination from global atmospheric transport. The association of general soil parameters with PCBs in Glasgow and with heavier congeners in Torino and Ljubljana indicates that retention of these compounds is occurring. The profiles obtained resemble Aroclor 1254 and 1260, which are important local sources. Nevertheless, differences in PCB profiles were observed among cities, due to the combined effects of the age of the contamination (which determines the time available for volatilisation and degradation), different sources of PCBs and differences in climate (which influence volatilisation and deposition).


Assuntos
Poluentes Ambientais/análise , Bifenilos Policlorados/análise , Solo/análise , Saúde da População Urbana/estatística & dados numéricos , Físico-Química , Cidades , Monitoramento Ambiental/métodos , Europa (Continente) , Humanos
8.
Environ Int ; 35(1): 214-25, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18835040

RESUMO

This paper provides a case-study analysis of the challenges in the implementation of national soil policies, which was developed by the authors in Part I of the review of regulatory decisions for environmental protection [Rodrigues SM, Pereira ME, Ferreira da Silva E, Hursthouse A, Duarte AC. A review of regulatory decisions for environmental management: Part I-challenges in the implementation of national soil policies. Environ Int 2009. doi:10.1016/j.envint.2008.08.007]. The Portuguese case was selected as a case-study since specific regulatory decisions for contaminated land management are still in the early stages of development. Given the gap between the situation at the EU level and the state of Portuguese soil policy development, it is of merit to consider national contaminated land policy regimes already in place within the EU and to see if these provide a suitable basis to define the main challenges and research needs for the implementation of a Portuguese contaminated land management strategy. A framework combining the D-P-S-I-R (drivers-pressures-sources-impacts-responses) structure of policy evaluation with the Source-Pathway-Receptor approach to health risk assessment is proposed to derive an effective regulatory framework for managing contaminated land in Portugal, using available information and only to develop new data and research where knowledge gaps exist. Funding site clean-up and assigning liability were identified as relevant factors currently hampering site remediation. Most relevant research needs for the development of contaminated land management practices in Portugal are those associated to the definition of a risk assessment framework and setting guidelines for the evaluation of risks posed to both humans and ecosystems. Other relevant and innovative features are the integration of soil function analysis into site investigations and the definition of a framework that combines risk assessment with soil function analysis. The analysis of the Portuguese case also provides insight into the discussions needed for the effective development of regulatory decisions for contaminated land management in countries with no history of implementing specific soil policies.


Assuntos
Conservação dos Recursos Naturais/métodos , Poluição Ambiental/prevenção & controle , Política de Saúde , Poluentes do Solo , Humanos , Portugal
9.
Environ Pollut ; 152(1): 73-81, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17602808

RESUMO

Soils from Aveiro, Glasgow, Ljubljana, Sevilla and Torino have been investigated in view of their potential for translocation of potentially toxic elements (PTE) to the atmosphere. Soils were partitioned into five size fractions and Cr, Cu, Ni, Pb and Zn were measured in the fractions and the whole soil. All PTE concentrated in the <10 microm fraction. Cr and Ni concentrated also in the coarse fraction, indicating a lithogenic contribution. An accumulation factor (AF) was calculated for the <2 and <10 microm fraction. The AF values indicate that the accumulation in the finer fractions is higher where the overall contamination is lower. AF for Cr and Ni are particularly low in Glasgow and Torino. An inverse relationship was found between the AF of some metals and the percentage of <10 microm particles that could be of use in risk assessment or remediation practices.


Assuntos
Monitoramento Ambiental/métodos , Resíduos Perigosos , Metais/análise , Poluentes do Solo/análise , Solo/análise , Poluentes Atmosféricos , Cromo , Cidades , Cobre/análise , Europa (Continente) , Chumbo/análise , Níquel/análise , Tamanho da Partícula , Zinco/análise
10.
J Environ Monit ; 9(9): 1001-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17726562

RESUMO

The purpose of this study was to determine the degree of contamination with polycyclic aromatic hydrocarbons (PAHs) in samples of urban soil from three European cities: Glasgow (UK), Torino (Italy) and Ljubljana (Slovenia). Fifteen PAHs (naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylene, indeno[1,2,3-c,d]pyrene) were measured in urban soil samples, using harmonised sampling, sample extraction and analyte quantification methods. Although the mean concentration of each PAH in urban soils of each city showed a wide range of values, high levels of contamination were only evident in Glasgow, where the sum of concentrations of 15 PAHs was in the range 1487-51,822 microg kg(-1), cf. ranges in the other two cities were about ten-fold lower (89.5-4488 microg kg(-1)). The three predominant PAHs were phenanthrene, fluoranthene and pyrene, with the sum of these compounds about 40% of the total PAH content. These data, together with some special molecular indices based on ratios of selected PAHs, suggest pyrogenic origins, especially motor vehicle exhausts, to be the major sources of PAHs in urban soils of the three cities. The largest concentrations for PAHs were often found in sites close to the historic quarters of the cities. Overall, the different climatic conditions, the organic carbon contents of soil, and the source apportionment were the dominant factors affecting accumulation of PAHs in soil.


Assuntos
Cidades , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Monitoramento Ambiental , Itália , Eslovênia , Reino Unido
11.
J Environ Monit ; 8(11): 1158-65, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17075623

RESUMO

Use of a harmonised sampling regime has allowed comparison of concentrations of copper, chromium, nickel, lead and zinc in six urban parks located in different European cities differing markedly in their climate and industrial history. Wide concentrations ranges were found for copper, lead and zinc at most sites, but for chromium and nickel a wide range was only seen in the Italian park, where levels were also considerably greater than in other soils. As might be expected, the soils from older cities with a legacy of heavy manufacturing industry (Glasgow, Torino) were richest in potentially toxic elements (PTEs); soils from Ljubljana, Sevilla and Uppsala had intermediate metal contents, and soils from the most recently established park, in the least industrialised city (Aveiro), displayed lowest concentrations. When principal component analysis was applied to the data, associations were revealed between pH and organic carbon content; and between all five PTEs. When pH and organic carbon content were excluded from the PCA, a distinction became clear between copper, lead and zinc (the "urban" metals) on the one hand, and chromium and nickel on the other. Similar results were obtained for the surface (0-10 cm depth) and sub-surface (10-20 cm depth) samples. Comparisons with target or limit concentrations were limited by the existence of different legislation in different countries and the fact that few guidelines deal specifically with public-access urban soils intended for recreational use.


Assuntos
Cidades/legislação & jurisprudência , Monitoramento Ambiental/normas , Resíduos Industriais/análise , Metais Pesados/análise , Poluentes do Solo/análise , Europa (Continente) , Metais Pesados/toxicidade , Poluentes do Solo/toxicidade
12.
J Environ Monit ; 8(9): 887-96, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16951748

RESUMO

An intertidal site in the Clyde Estuary, UK, was selected to evaluate the role of sediment geochemistry on the bioaccumulation of polychlorinated biphenyls (PCBs) by mussels (Mytilus edulis). The area had previously been identified as showing anomalously high levels of PCB contamination (over 1,500 microg kg(-1) total PCB in sediment, 22 congeners). Samples of surface sediment and M. edulis were collected from two closely located sites, one within the anomalous area and another representing typical PCB contamination in the estuary. Sediment samples were separated into grain size fractions and analysed for a range of biomarker compounds, PCBs and sediment mineralogy. The anomalous site showed an atypical association of PCBs with sediment properties, despite both locations showing influence of both petrogenic and pyrogenic organic contamination. Interrogation of data using correlation and principal component analysis showed that sediment mineralogy as well as organic matter composition influenced PCB congener distribution. One sediment source was found to control the PCB concentration in mussels at both locations and clay mineralogy appears to control PCB uptake by biota with preference for higher molecular weight congeners. Overall bioavailability is determined by sediment TOC.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Mytilus edulis/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água , Animais , Disponibilidade Biológica , Poluentes Ambientais/análise , Poluentes Ambientais/farmacocinética , Cadeia Alimentar , Sedimentos Geológicos/química , Mytilus edulis/química , Bifenilos Policlorados/análise , Bifenilos Policlorados/farmacocinética , Análise de Componente Principal , Distribuição Tecidual , Reino Unido , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/farmacocinética
13.
Sci Total Environ ; 368(2-3): 926-36, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16750244

RESUMO

The objective of this study was to quantify and assess for the first time the variability of total mercury in urban soils at a European level, using a systematic sampling strategy and a common methodology. We report results from a comparison between soil samples from Aveiro (Portugal), Glasgow (Scotland), Ljubljana (Slovenia), Sevilla (Spain), Torino (Italy) and Uppsala (Sweden). At least 25 sampling points (in about 4-5 ha) from a park in each city were sampled at two depths (0-10 and 10-20 cm). Total mercury was determined by pyrolysis atomic absorption spectrometry with gold amalgamation. The quality of results was monitored using certified reference materials (BCR 142R and BCR 141R). Measured total mercury contents varied from 0.015 to 6.3 mg kg(-1). The lowest median values were found in Aveiro, for both surface (0-10 cm) and sub-surface (10-20 cm) samples (0.055 and 0.054 mg kg(-1), respectively). The highest median mercury contents in soil samples were found in samples from Glasgow (1.2 and 1.3 mg kg(-1), for surface and sub-surface samples, respectively). High variability of mercury concentrations was observed, both within each park and between cities. This variability reflecting contributions from natural background, previous anthropogenic activities and differences in the ages of cities and land use, local environmental conditions as well as the influence of their location within the urban area. Short-range variability of mercury concentrations was found to be up to an order of magnitude over the distance of only a few 10 m.


Assuntos
Mercúrio/análise , Poluentes do Solo/análise , Cidades , Monitoramento Ambiental , Europa (Continente)
14.
Environ Geochem Health ; 25(1): 57-62, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12901079

RESUMO

Water quality models of urban systems have previously focused on point source (sewerage system) inputs. Little attention has been given to diffuse inputs and research into diffuse pollution has been largely confined to agriculture sources. This paper reports on new research that is aimed at integrating diffuse inputs into an urban water quality model. An integrated model is introduced that is made up of four modules: hydrology, contaminant point sources, nutrient cycling and leaching. The hydrology module, T&T consists of a TOPMODEL (a TOPography-based hydrological MODEL), which simulates runoff from pervious areas and a two-tank model, which simulates runoff from impervious urban areas. Linked into the two-tank model, the contaminant point source module simulates the overflow from the sewerage system in heavy rain. The widely known SOILN (SOIL Nitrate model) is the basis of nitrogen cycle module. Finally, the leaching module consists of two functions: the production function and the transfer function. The production function is based on SLIM (Solute Leaching Intermediate Model) while the transfer function is based on the 'flushing hypothesis' which postulates a relationship between contaminant concentrations in the receiving water course and the extent to which the catchment is saturated. This paper outlines the modelling methodology and the model structures that have been developed. An application of this model in the White Cart catchment (Glasgow) is also included.


Assuntos
Modelos Teóricos , Nitratos/análise , Nitrogênio/química , Esgotos/química , Poluentes da Água/análise , Agricultura , Cidades , Difusão , Fertilizantes , Previsões , Escócia , Movimentos da Água
15.
J Environ Radioact ; 56(3): 299-307, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11468821

RESUMO

137Cs extraction experiments were performed on 14 contaminated soils from NW Italy with different characteristics and mineralogical composition. Solutions of HCl (pH = 0.5) and buffered EDTA/ammonium acetate (Lakanen solution) were used to assess bioavailability. The results show that less than 2% of 137Cs is available for leaching and/or root uptake. Even within a complex natural system it was possible to identify the amount of swelling clays (vermiculite + smectite) as the main control on Cs mobility under acidic conditions. The ammonium ion appears to be effective in desorbing Cs and its role is briefly discussed in terms of crystal chemistry. The relevance of mineralogy in assessing soil vulnerability is underlined.


Assuntos
Silicatos de Alumínio/química , Radioisótopos de Césio/farmacocinética , Poluentes Radioativos do Solo/farmacocinética , Disponibilidade Biológica , Radioisótopos de Césio/análise , Radioisótopos de Césio/química , Argila , Cristalização , Concentração de Íons de Hidrogênio , Raízes de Plantas , Poluentes Radioativos do Solo/análise
16.
J Environ Monit ; 3(1): 49-60, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11253019

RESUMO

The environmental impact of metallic contaminants in soils and sediments is dependent both on the chemical speciation of the metal and the response of the matrix to biological and physicochemical conditions. These factors are responsible for the mobilisation of the metal from the solid into the aquatic phase and hence transport within the immediate vicinity, impacting on the rate of dispersal, dilution, uptake and transfer into living systems. The impact of changing environmental conditions on the contaminant inventory can be to enhance or moderate these phenomena, with subsequent consequences for the broader risk assessment of the contaminants. Remediation of metallic contaminants can only be brought about by their removal from the site or by establishing conditions which favour their retention in the solid phase. A wide range of in situ and ex situ approaches are available and a summary overview is presented. The examples show assessment at both the field and laboratory scale and demonstrate an equally wide range of success in achieving remediation targets. This can be attributed to limitations in ensuring that the desired conditions for the initial removal or immobilisation process are met and maintained over a suitable period of time. Three areas are reviewed which include: the transport and release of metallic contaminants in estuarine sediments and the assessment of their potential to impact on biota; terrestrial contamination systems involving the release of chromium from waste ore contaminating urban environments; the response of metal-contaminated wastes to changing environmental conditions and the impact of natural bioremediation. The focus of the discussion is to highlight the generation of reliable speciation information and the problems associated with impact and risk assessment. Particular issues of concern are the laboratory to field scale evaluation of contaminant behaviour and the approach used to assess the reliability of remediation options. In conclusion, part of a recent initiative in risk assessment and the development of pilot scale experimental systems to study long-term behaviour are addressed as future goals to fill gaps in current research.


Assuntos
Poluição Ambiental/prevenção & controle , Sedimentos Geológicos/química , Metais Pesados/química , Poluentes do Solo/análise , Animais , Conservação dos Recursos Naturais , Medição de Risco , Escócia , População Urbana , Poluentes Químicos da Água/análise
17.
J Environ Monit ; 3(6): 646-53, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11785640

RESUMO

Benzene (with toluene, ethyl benzene and xylene isomers) concentrations were measured at nine locations in Renfrewshire district between February 1996 and July 1998. Samples were collected by both active and diffusion-based sampling and the compounds were quantified by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The study highlighted the ability of diffusion sampling to provide an effective district-wide assessment of volatile organic compounds (VOCs) in urban environmental assessment. Vehicle movement was confirmed as the dominant influence on benzene and associated VOCs in the atmosphere, with strong variations in monthly average concentrations across the study area. For benzene, peak monthly averages were observed on the order of 5-6 ppb v/v, with minimum values of < <0.5 ppb v/v. The impact of a major traffic intervention on benzene levels was followed, and was found to influence atmospheric concentrations over a wide geographical area. An evaluation of the relationship between VOCs and meteorological parameters identified the impact of photo-oxidation and air mass mixing on average atmospheric concentrations.


Assuntos
Poluentes Atmosféricos/análise , Benzeno/análise , Monitoramento Ambiental/métodos , Cromatografia Gasosa , Cidades , Difusão , Ionização de Chama , Compostos Orgânicos/análise , Oxirredução , Escócia , Emissões de Veículos , Volatilização
18.
Environ Geochem Health ; 15(2-3): 163-71, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24198112

RESUMO

The transuranium elements, Np, Pu and Am discharged from the BNFL fuel reprocessing plant at Sellafield have accumulated in the local environment. The processes responsible for their dispersal rely both on physical transportation and their chemical reactivity. The transuranics have a complex chemistry, with multiple oxidation states and a strongly polarising character. In the environment, the particle active III/IV and more mobile VNI oxidation state groups are important and govern their geochemical behaviour and subsequent dispersal.Studies of the behaviour of the transuranics, particularly Pu, in the Irish Sea, have shown that the majority of the radionuclides in the liquid effluent discharged from Sellafield, quickly becomes associated with the marine sediments. Their dispersal and distribution in the environment is then governed primarily by the movement of particulate material and for some sites it has been suggested that sediment profiles preserve the historical record of discharges from the plant.In tidally inundated soils, radionuclide levels are greatly enhanced. These soils are water-logged for long periods of the year, are strongly anoxic and accretion rate are very low. The distribution of Np, Pu and Am in the soil suggests that simple sedimentary accumulation mechanism cannot provide an adequate explanation for the profiles observed. From preliminary studies of soil pore water composition and detailed analysis of the variation of isotopic ratios in the soil cores, it is apparent that a small but significant component of the radionuclide inventory is mobile. In addition, it is clear that the mechanisms responsible for this mobility allows differentiation between the transuranium nuclides.

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