1
|
Vicente ED, Calvo AI, Sainnokhoi TA, Kováts N, de la Campa AS, de la Rosa J, Oduber F, Nunes T, Fraile R, Tomé M, Alves CA. Indoor PM from residential coal combustion: Levels, chemical composition, and toxicity. Sci Total Environ 2024; 918:170598. [PMID: 38340837 DOI: 10.1016/j.scitotenv.2024.170598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/29/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024]
Abstract
Indoor air quality is crucial for human health due to the significant time people spend at home, and it is mainly affected by internal sources such as solid fuel combustion for heating. This study investigated the indoor air quality and health implications associated with residential coal burning covering gaseous pollutants (CO, CO2 and total volatile organic compounds), particulate matter, and toxicity. The PM10 chemical composition was obtained by ICP-MS/OES (elements), ion chromatography (water-soluble ions) and thermal-optical analysis (organic and elemental carbon). During coal combustion, PM10 levels were higher (up to 8.8 times) than background levels and the indoor-to-outdoor ratios were, on average, greater than unity, confirming the existence of a significant indoor source. The chemical characterisation of PM10 revealed increased concentrations of organic carbon and elemental carbon during coal combustion as well as arsenic, cadmium and lead. Carcinogenic risks associated with exposure to arsenic exceeded safety thresholds. Indoor air quality fluctuated during the study, with varying toxicity levels assessed using the Aliivibrio fischeri bioluminescence inhibition assay. These findings underscore the importance of mitigating indoor air pollution associated with coal burning and highlight the potential health risks from long-term exposure. Effective interventions are needed to improve indoor air quality and reduce health risks in coal-burning households.
Collapse
Affiliation(s)
- Estela D Vicente
- Department of Physics, University of León, 24071 León, Spain; Department of Environment and Planning, Centre for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Ana I Calvo
- Department of Physics, University of León, 24071 León, Spain
| | - Tsend-Ayush Sainnokhoi
- Centre for Environmental Sciences, University of Pannonia, Egyetem str. 10, 8200 Veszprém, Hungary
| | - Nora Kováts
- Centre for Environmental Sciences, University of Pannonia, Egyetem str. 10, 8200 Veszprém, Hungary
| | - Ana Sánchez de la Campa
- Associate Unit CSIC-University of Huelva "Atmospheric Pollution", Centre for Research in Sustainable Chemistry - CIQSO, University of Huelva, E21071 Huelva, Spain; Department of Mining, Mechanic, Energetic and Construction Engineering, ETSI, University of Huelva, 21071 Huelva, Spain
| | - Jesús de la Rosa
- Associate Unit CSIC-University of Huelva "Atmospheric Pollution", Centre for Research in Sustainable Chemistry - CIQSO, University of Huelva, E21071 Huelva, Spain; Department of Mining, Mechanic, Energetic and Construction Engineering, ETSI, University of Huelva, 21071 Huelva, Spain
| | - Fernanda Oduber
- Department of Physics, University of León, 24071 León, Spain
| | - Teresa Nunes
- Department of Environment and Planning, Centre for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193 Aveiro, Portugal
| | - Roberto Fraile
- Department of Physics, University of León, 24071 León, Spain
| | - Mário Tomé
- PROMETHEUS, School of Technology and Management (ESTG), Polytechnic University of Viana do Castelo, 4900-348 Viana do Castelo, Portugal
| | - Célia A Alves
- Department of Environment and Planning, Centre for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193 Aveiro, Portugal
| |
Collapse
|
2
|
Rodríguez-Fernández A, Aloisi I, Blanco-Alegre C, Vega-Maray AM, Valencia-Barrera RM, Suanno C, Calvo AI, Fraile R, Fernández-González D. Identifying key environmental factors to model Alt a 1 airborne allergen presence and variation. Sci Total Environ 2024; 917:170597. [PMID: 38307265 DOI: 10.1016/j.scitotenv.2024.170597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/26/2024] [Accepted: 01/29/2024] [Indexed: 02/04/2024]
Abstract
Fungal spores, commonly found in the atmosphere, can trigger important respiratory disorders. The glycoprotein Alt a 1 is the major allergen present in conidia of the genus Alternaria and has a high clinical relevance for people sensitized to fungi. Exposure to this allergen has been traditionally assessed by aerobiological spore counts, although this does not always offer an accurate estimate of airborne allergen load. This study aims to pinpoint the key factors that explain the presence and variation of Alt a 1 concentration in the atmosphere in order to establish exposure risk periods and improve forecasting models. Alternaria spores were sampled using a Hirst-type volumetric sampler over a five-year period. The allergenic fraction from the bioaerosol was collected using a low-volume cyclone sampler and Alt a 1 quantified by Enzyme-Linked ImmunoSorbent Assay. A cluster analysis was executed in order to group days with similar environmental features and then analyze days with the presence of the allergen in each of them. Subsequently, a quadratic discriminant analysis was performed to evaluate if the selected variables can predict days with high Alt a 1 load. The results indicate that higher temperatures and absolute humidity favor the presence of Alt a 1 in the atmosphere, while time of precipitation is related to days without allergen. Moreover, using the selected parameters, the quadratic discriminant analysis to predict days with allergen showed an accuracy rate between 67 % and 85 %. The mismatch between daily airborne concentration of Alternaria spores and allergen load can be explained by the greater contribution of medium-to-long distance transport of the allergen from the major emission sources as compared with spores. Results highlight the importance of conducting aeroallergen quantification studies together with spore counts to improve the forecasting models of allergy risk, especially for fungal spores.
Collapse
Affiliation(s)
| | - Iris Aloisi
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | | | - Ana María Vega-Maray
- Department of Biodiversity and Environmental Management (Botany), University of León, León, Spain
| | | | - Chiara Suanno
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | | | | | - Delia Fernández-González
- Department of Biodiversity and Environmental Management (Botany), University of León, León, Spain; Institute of Atmospheric Sciences and Climate-CNR, Bologna, Italy
| |
Collapse
|
3
|
Blanco-Alegre C, Calvo AI, Castro A, Oduber F, Alonso-Blanco E, Alves C, Cerqueira M, López R, Lucarelli F, Nava S, Calzolai G, Fraile R. The role of snow in scavenging aerosol particles: A physical-chemical characterization. Sci Total Environ 2024; 906:167608. [PMID: 37804986 DOI: 10.1016/j.scitotenv.2023.167608] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 10/02/2023] [Accepted: 10/03/2023] [Indexed: 10/09/2023]
Abstract
The below cloud scavenging of aerosols by snow has been analysed in León (NW Spain). Six snow events were registered over the course of one year of study. Ultrafine and accumulation aerosol particles were measured using a scanning mobility particle sizer spectrometer, while hydrometeors were characterized using a disdrometer. Furthermore, the chemical composition of the melted snow-water samples (soluble and insoluble fractions) was analysed. The scavenging coefficient (λ) showed a great variability among events. An effective washing of particles was observed during the first 30 min of snowfall. The mean change in the scavenging efficiency (%ΔC) of particle number concentration (PNC) and λ coefficient during this time interval were: i) nucleation mode: 36.3 % and 3.02 · 10-4 s-1; ii) Aitken mode: 30.4 % and 2.37 · 10-4 s-1 and iii) accumulation mode: 22.4 % and 1.77 · 10-4 s-1. The range of particle sizes that is less efficiently scavenged by snowfall was observed between 400 and 600 nm. When analyzing the whole snow event, an increase of PNC was observed. Two possible explanations underlie this behaviour: it could be caused by changes in air masses or by the resuspension of aerosol particles scavenged by snowflakes upon reaching the ground. A clear relationship was observed between Ca2+, SO42- and NO3- concentrations of aerosol particles before the snow event and the concentrations registered in the melted snow-water. The largest and smallest changes in aerosol number concentrations were caused by snowflakes of 3 and 6 mm in diameter, respectively. The particle size distributions (PSD) were fitted to log-normal distributions and the parameters were compared before and after snowfall.
Collapse
Affiliation(s)
- C Blanco-Alegre
- Department of Physics, Universidad de León, Campus de Vegazana, 24071 León, Spain.
| | - A I Calvo
- Department of Physics, Universidad de León, Campus de Vegazana, 24071 León, Spain
| | - A Castro
- Department of Physics, Universidad de León, Campus de Vegazana, 24071 León, Spain
| | - F Oduber
- Department of Physics, Universidad de León, Campus de Vegazana, 24071 León, Spain
| | - E Alonso-Blanco
- Centre for Energy, Environment and Technology Research (CIEMAT), Environment Department, Madrid, Spain
| | - C Alves
- Centre for Environmental and Marine Studies (CESAM), Department of Environment and Planning, University of Aveiro, Aveiro 3810-193, Portugal
| | - M Cerqueira
- Centre for Environmental and Marine Studies (CESAM), Department of Environment and Planning, University of Aveiro, Aveiro 3810-193, Portugal
| | - R López
- Department of Chemistry, Universidad de León, Campus de Vegazana, 24071 León, Spain
| | - F Lucarelli
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy
| | - S Nava
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy
| | - G Calzolai
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy
| | - R Fraile
- Department of Physics, Universidad de León, Campus de Vegazana, 24071 León, Spain
| |
Collapse
|
4
|
Vicente ED, Calvo AI, Alves C, Blanco-Alegre C, Candeias C, Rocha F, Sánchez de la Campa A, Fraile R. Residential combustion of coal: Effect of the fuel and combustion stage on emissions. Chemosphere 2023; 340:139870. [PMID: 37633612 DOI: 10.1016/j.chemosphere.2023.139870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 07/26/2023] [Accepted: 08/17/2023] [Indexed: 08/28/2023]
Abstract
Worldwide coal is still used for household heating purposes not only because it is available and cheap but also due to behavioural issues. Regional variability in fuels and combustion appliances make accurate emission estimates from this source hard to achieve. In the present study, gaseous (CO, VOCs, SO2 and NOX) and particulate matter (TSP) emission factors (EFs) were determined for Spanish household coal combustion covering three commercial coals and distinct combustion stages and mimicking usage patterns in real households. TSP samples were analysed to determine water-soluble inorganic ions, metal(loid)s, and organic and elemental carbon (OC and EC). Additionally, the morphology of the emitted particles was also characterised. CO (3.43-169 g kg-1), NOX (1.29-6.00 g kg-1) and SO2 (8.96-22.3 g kg-1) EFs showed no trend regarding the combustion stage or coal type tested. On the other hand, VOC, TSP and EC EFs were higher for the ignition/devolatilisation combustion stage, regardless of the fuel tested. TSP EFs (0.085-1.08 g kg-1) increased with increasing coal volatile matter while the opposite trend was recorded for VOC emissions (0.045-3.39 gC kg-1). TSP carbonaceous matter was dominated by EC while OC represented a small fraction of the particulate mass emitted (less than 8 %wt.). Inorganic compounds composed an important fraction of the TSP samples. Sulphate particulate mass fractions (8.66-22.9 %wt.) appeared to increase with coal S-content. Coal combustion released particles with diverse morphologies, including silicate-rich particles, ferro- and glassy-spheres. This study provides novel emission factors to update emission inventories of residential coal combustion. Additionally, detailed chemical profiles were obtained for source apportionment.
Collapse
Affiliation(s)
- E D Vicente
- Department of Physics, University of León, León, 24071, Spain; Department of Environment and Planning, Centre for Environmental and Marine Studies (CESAM), University of Aveiro, Aveiro, 3810-193, Portugal.
| | - A I Calvo
- Department of Physics, University of León, León, 24071, Spain
| | - C Alves
- Department of Environment and Planning, Centre for Environmental and Marine Studies (CESAM), University of Aveiro, Aveiro, 3810-193, Portugal
| | - C Blanco-Alegre
- Department of Physics, University of León, León, 24071, Spain
| | - C Candeias
- Department of Geosciences, Geobiosciences, Geotechnologies and Geoengineering Research Centre (GeoBioTec), University of Aveiro, 3810-193, Aveiro, Portugal
| | - F Rocha
- Department of Geosciences, Geobiosciences, Geotechnologies and Geoengineering Research Centre (GeoBioTec), University of Aveiro, 3810-193, Aveiro, Portugal
| | - A Sánchez de la Campa
- Associate Unit CSIC-University of Huelva "Atmospheric Pollution", Centre for Research in Sustainable Chemistry - CIQSO, University of Huelva, E21071, Huelva, Spain; Department of Earth Science, Faculty of Experimental Sciences, University of Huelva, Campus El Carmen s/n, 21071, Huelva, Spain
| | - R Fraile
- Department of Physics, University of León, León, 24071, Spain
| |
Collapse
|
5
|
Pardo N, Sainz-Villegas S, Calvo AI, Blanco-Alegre C, Fraile R. Connection between Weather Types and Air Pollution Levels: A 19-Year Study in Nine EMEP Stations in Spain. Int J Environ Res Public Health 2023; 20:2977. [PMID: 36833673 PMCID: PMC9964285 DOI: 10.3390/ijerph20042977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/03/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
This study focuses on the analysis of the distribution, both spatial and temporal, of the PM10 (particulate matter with a diameter of 10 µm or less) concentrations recorded in nine EMEP (European Monitoring and Evaluation Programme) background stations distributed throughout mainland Spain between 2001 and 2019. A study of hierarchical clusters was used to classify the stations into three main groups with similarities in yearly concentrations: GC (coastal location), GNC (north-central location), and GSE (southeastern location). The highest PM10 concentrations were registered in summer. Annual evolution showed statistically significant decreasing trends in PM10 concentration in all the stations covering a range from -0.21 to -0.50 µg m-3/year for Barcarrota and Víznar, respectively. Through the Lamb classification, the weather types were defined during the study period, and those associated with high levels of pollution were identified. Finally, the values exceeding the limits established by the legislation were analyzed for every station assessed in the study.
Collapse
Affiliation(s)
- Nuria Pardo
- Department of Applied Physics, Faculty of Sciences, University of Valladolid, Paseo de Belén, 7, 47011 Valladolid, Spain
| | - Samuel Sainz-Villegas
- Department of Physics, University of León, 24071 León, Spain
- IHCantabria-Instituto de Hidráulica Ambiental de la Universidad de Cantabria, 39011 Santander, Spain
| | - Ana I. Calvo
- Department of Physics, University of León, 24071 León, Spain
| | | | - Roberto Fraile
- Department of Physics, University of León, 24071 León, Spain
| |
Collapse
|
6
|
Blanco-Alegre C, Pont V, Calvo AI, Castro A, Oduber F, Pimienta-Del-Valle D, Fraile R. Links between aerosol radiative forcing and rain characteristics: Stratiform and convective precipitation. Sci Total Environ 2022; 819:152970. [PMID: 35007569 DOI: 10.1016/j.scitotenv.2022.152970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 12/22/2021] [Accepted: 01/04/2022] [Indexed: 06/14/2023]
Abstract
The radiative forcing before and after rain events was studied between 12 February 2016 and 14 March 2017 in León, Spain. For this purpose, the radiative forcing fluxes were calculated using the Radiative Transfer Model Global Atmospheric ModEl (RTM GAME). After the application of a set of selection criteria (based on the availability of AERONET data, rain characteristics and lightning maps), 16 stratiform rain events were identified, concentrated in spring and winter, and 15 convective rain events were found concentrated in spring and summer. Rainfall events were grouped according to the atmospheric forcing (ΔFATM) before rain: "low" or "high" (lower or higher than 30 W m-2). The threshold has been set at this value because it is the mean ΔFATM of all the selected events before rain. There were significant statistical differences between stratiform and convective events in rain duration, mean raindrop diameter and parameters a and b of radar reflectivity Z and rainfall intensity R relationship (Z = a Rb). When comparing "low" and "high" groups, raindrop diameter was similar in stratiform (0.51 ± 0.08 vs 0.48 ± 0.12 mm) and convective events (0.96 ± 0.98 vs 0.83 ± 0.63 mm), registering higher values for the latter. In stratiform events, the rain scavenging effect on aerosol particles is clearly observed in the "high" group with a decrease of radiative forcing of -27.0 ± 25.3%, and to a lesser extent, in the "low" group, probably because of a lower aerosol load in the atmosphere. In stratiform events, the mode of the raindrop size gamma distribution presented statistical differences between "low" (0.25 ± 0.13 mm) and "high" (0.35 ± 0.05 mm) groups. We claim that this points towards a relationship between radiative forcing before rain and the specific characteristics of rainfall measured at ground level. This study increases our knowledge on the important role of rainwater as a clean agent of the atmosphere and its impact on climate (through radiative forcing).
Collapse
Affiliation(s)
- C Blanco-Alegre
- Department of Physics, IMARENAB University of León, 24071 León, Spain.
| | - V Pont
- Université Toulouse III, Laboratoire d'Aérologie UMR 5560, 31400 Toulouse, France.
| | - A I Calvo
- Department of Physics, IMARENAB University of León, 24071 León, Spain.
| | - A Castro
- Department of Physics, IMARENAB University of León, 24071 León, Spain.
| | - F Oduber
- Department of Physics, IMARENAB University of León, 24071 León, Spain.
| | - D Pimienta-Del-Valle
- Information Processing and Telecommunications Center, Universidad Politécnica de Madrid, 28040 Madrid, Spain.
| | - R Fraile
- Department of Physics, IMARENAB University of León, 24071 León, Spain.
| |
Collapse
|
7
|
Blanco-Alegre C, Calvo AI, Alonso-Blanco E, Castro A, Oduber F, Fraile R. Evolution of size-segregated aerosol concentration in NW Spain: A two-step classification to identify new particle formation events. J Environ Manage 2022; 304:114232. [PMID: 34933267 DOI: 10.1016/j.jenvman.2021.114232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 11/18/2021] [Accepted: 12/01/2021] [Indexed: 06/14/2023]
Abstract
Real-time measurements of particles in the 15-736 nm range have been obtained by a Scanning Mobility Particle Sizer to characterize the evolution of particle size distribution and new particle formation (NPF) events in an urban background area. The annual, weekly and diurnal variations of the modal (nucleation (Nnuc), Aitken (NAit) and accumulation (Nacc)) particle concentrations were characterised. The NAit and Nacc registered their maximums in cold months during rush hours, in the morning (0600-0900 UTC) and in the afternoon (1700-2000 UTC), while the maximums for Nnuc were reached in warm months during midday hours. NAit, Nacc and Ntotal showed a significant negative correlation with wind speed and a different relationship with the planetary boundary layer (PBL) height by periods. In the warm period, a positive significant correlation between PBL and Nnuc was registered, indicating that the higher dispersion promoted by a high PBL causes favourable conditions for the occurrence of NPF events (a low polluted atmosphere). NPF processes are one of the main sources of ultrafine particles (<100 nm) in the warm period. After a visual-based classification, 45 NPF events of type Ia (strong and with a good confidence level) were identified and analysed, occurring primarily between 1100 and 1500 UTC, mainly in spring and summer. In addition, a two-step method was developed for identifying NPF events: cluster analysis followed by discriminant analysis. The application of discriminant analysis to one of the clusters, grouping 93 days, enabled us to identify 55 of the 56 NPF events days included in the cluster. This method is a valuable tool for identifying NPF events quickly and effectively.
Collapse
Affiliation(s)
- C Blanco-Alegre
- Department of Physics, IMARENAB University of León, 24071, León, Spain.
| | - A I Calvo
- Department of Physics, IMARENAB University of León, 24071, León, Spain.
| | - E Alonso-Blanco
- Centre for Energy, Environment and Technology Research (CIEMAT), Environment Department, Madrid, Spain.
| | - A Castro
- Department of Physics, IMARENAB University of León, 24071, León, Spain.
| | - F Oduber
- Department of Physics, IMARENAB University of León, 24071, León, Spain.
| | - R Fraile
- Department of Physics, IMARENAB University of León, 24071, León, Spain.
| |
Collapse
|
8
|
Blanco-Alegre C, Calvo AI, Castro A, Oduber F, Alonso-Blanco E, Fraile R. Scavenging of submicron aerosol particles in a suburban atmosphere: The raindrop size factor. Environ Pollut 2021; 285:117371. [PMID: 34090072 DOI: 10.1016/j.envpol.2021.117371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 04/13/2021] [Accepted: 05/04/2021] [Indexed: 06/12/2023]
Abstract
This paper studies the below-cloud scavenging caused by precipitation on ultrafine and accumulation modes, as well as the role of the different raindrop sizes in an urban environment. The equipment used to measure aerosol particles and raindrop variables includes a scanning mobility particle sizer spectrometer-SMPS and a Laser Precipitation Monitor (LPM), respectively. An analysis of the scavenging efficiency and the scavenging coefficient (λ) by modes and rain intensities was carried out. The main results observed have been: i) the nucleation (between 14 and 30 nm), Aitken (between 30 and 100 nm), accumulation 1 (between 100 and 300) and accumulation 2 (between 300 and 1000 nm) modes presented a scavenging efficiency of 15, 4, 22 and 21%, respectively; ii) events with rain intensities between 1 and 3 mm h-1 caused less scavenging in all modes; iii) raindrop sizes between 1.25 and 3.5 mm scavenged mainly particle sizes between 70 and 250 nm. Lower scavenging was observed on particle sizes >300 nm, and particle sizes >600 nm were only scavenged by raindrop sizes >4.75 mm; iv) the respirable fraction before and after the rain events presented a statically significant decrease of -35%. The combination in this study of SMPS and disdrometer measurements has resulted in a more detailed characterization of the influence of this process on the submicrometer aerosol fraction, noting that below-cloud scavenging is one of the main removal pathways for submicrometer aerosol particles. This study thus contributes to improving the current state of knowledge of below-cloud scavenging.
Collapse
Affiliation(s)
- C Blanco-Alegre
- Department of Physics, IMARENAB University of León, 24071, León, Spain
| | - A I Calvo
- Department of Physics, IMARENAB University of León, 24071, León, Spain.
| | - A Castro
- Department of Physics, IMARENAB University of León, 24071, León, Spain
| | - F Oduber
- Department of Physics, IMARENAB University of León, 24071, León, Spain
| | - E Alonso-Blanco
- Centre for Energy, Environment and Technology Research (CIEMAT), Environment Department, Madrid, Spain
| | - R Fraile
- Department of Physics, IMARENAB University of León, 24071, León, Spain.
| |
Collapse
|
9
|
Blanco-Alegre C, Castro A, Calvo AI, Oduber F, Fernández-González D, Valencia-Barrera RM, Vega-Maray AM, Molnár T, Fraile R. Towards a model of wet deposition of bioaerosols: The raindrop size role. Sci Total Environ 2021; 767:145426. [PMID: 33550056 DOI: 10.1016/j.scitotenv.2021.145426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/16/2021] [Accepted: 01/21/2021] [Indexed: 06/12/2023]
Abstract
Bioaerosols play a major role in the plant life of ecosystems. In addition, they have a profound impact on human health, since they may cause lung diseases or allergies. The key objective of this study is to assess the below cloud scavenging effect of rainfall on pollen concentration. The analysis is based on a sampling carried out in León, Spain, between 2015 and 2018. The rainfall variables and the pollen concentrations have been obtained with a disdrometer and a volumetric Hirst type spore-trap, respectively. In order to evaluate the scavenging, three parameters have been calculated: scavenging efficiency (through the concentration-weighted average (%ΔC)), the scavenging coefficient (λ) and the percentage of events with a decrease in pollen concentration (%ES) also called events with effective scavenging. 71% of rain events presented an effective scavenging that affected all types of pollen. The %ΔC mean value of total pollen was 24 ± 18% (positive values indicate an effective scavenging) and the types of pollen with the highest values were Castanea and Cupressaceae (71 and 40%, respectively). A linear model (R2 = 0.94) to estimate the pollen concentration after rain was built with variables such as pollen concentration before rain and other variables from a weather station and a disdrometer. Furthermore, we have shown the possibility of knowing in real time the probable Cupressaceae pollen concentration, from the initial pollen concentration and the physical parameters of rain (such as raindrop size, rain intensity or volume swept by raindrops in their falling path).
Collapse
Affiliation(s)
| | - Amaya Castro
- Department of Physics (IMARENAB), University of León, Spain.
| | - Ana I Calvo
- Department of Physics (IMARENAB), University of León, Spain.
| | - Fernanda Oduber
- Department of Physics (IMARENAB), University of León, Spain.
| | - Delia Fernández-González
- Department of Biodiversity and Environmental Management, University of León, Spain; Institute of Atmospheric Sciences and Climate, National Research Council, Bologna, Italy.
| | | | - Ana María Vega-Maray
- Department of Biodiversity and Environmental Management, University of León, Spain.
| | - Tibor Molnár
- Szent Istvan University, Institute of Agricultural Sciences and Rural Development, Hungary.
| | - Roberto Fraile
- Department of Physics (IMARENAB), University of León, Spain.
| |
Collapse
|
10
|
Oduber F, Calvo AI, Blanco-Alegre C, Castro A, Alves C, Cerqueira M, Lucarelli F, Nava S, Calzolai G, Martin-Villacorta J, Esteves V, Fraile R. Towards a model for aerosol removal by rain scavenging: The role of physical-chemical characteristics of raindrops. Water Res 2021; 190:116758. [PMID: 33387951 DOI: 10.1016/j.watres.2020.116758] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/14/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
A one-year study was carried out in León, Spain, in order to characterize physically and chemically the precipitation. With the aim of studying the scavenging process of atmospheric pollutants, scavenging ratio and removal coefficients were calculated through physical parameters of raindrops (obtained by disdrometer data) and through chemical properties of aerosols. Finally, linear models for the prediction of the chemical composition of rainwater and the efficiency of the removal effect were established. In general, the rainwater was dominated by NH4+ > SO42- > NO3- in all seasons. Higher ion concentrations and conductivity and lowest pH were observed in summer, due to the low volume of rain. In winter, the high values of Na+ and Cl- in the rainwater showed the contribution from marine sources, while in summer the high concentrations of Ca2+, Mg2+, SO42-, NH4+ and NO3- reflected the contribution from both crustal and anthropogenic sources. The linear models revealed that the amount of dissolved organic carbon and of the water-soluble ions in rain samples, Ca2+, SO42-, NO3-, increases with the volume swept by the falling drops. Insoluble carbon fraction has a negative dependence with the volume swept and positive with the diameter of the raindrop. Removal coefficients are affected by the concentration in the air of each species before precipitation, the duration of the event and the time elapsed between two precipitation events.
Collapse
Affiliation(s)
- Fernanda Oduber
- Department of Physics, IMARENAB, University of León, León, Spain
| | - Ana Isabel Calvo
- Department of Physics, IMARENAB, University of León, León, Spain.
| | | | - Amaya Castro
- Department of Physics, IMARENAB, University of León, León, Spain
| | - Célia Alves
- Department of Environment and Planning, CESAM, University of Aveiro, Aveiro, Portugal
| | - Mário Cerqueira
- Department of Environment and Planning, CESAM, University of Aveiro, Aveiro, Portugal
| | - Franco Lucarelli
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy
| | - Silvia Nava
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy
| | - Giulia Calzolai
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy
| | | | - Valdemar Esteves
- Department of Chemistry, CESAM, University of Aveiro, Aveiro, Portugal
| | - Roberto Fraile
- Department of Physics, IMARENAB, University of León, León, Spain
| |
Collapse
|
11
|
Oduber F, Calvo AI, Castro A, Blanco-Alegre C, Alves C, Calzolai G, Nava S, Lucarelli F, Nunes T, Barata J, Fraile R. Characterization of aerosol sources in León (Spain) using Positive Matrix Factorization and weather types. Sci Total Environ 2021; 754:142045. [PMID: 32916490 DOI: 10.1016/j.scitotenv.2020.142045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 08/24/2020] [Accepted: 08/26/2020] [Indexed: 06/11/2023]
Abstract
A one-year aerosol sampling campaign, between 2016 and 2017, was conducted in a suburban area of León city, Spain. An association between the Positive Matrix Factorization (PMF) results and air masses through circulation weather types was carried out, through the construction of linear models from the PM10 concentrations and its chemical composition. The aerosol sources, identified by PMF six-factor solution, were: traffic (29%), aged sea salt (26%), secondary aerosols (16%), dust (13%), marine aerosol (7%) and biomass burning (3%). Traffic and secondary factors showed the highest PM10 contribution in the hybrid cyclonic types with wind component from the first and second quadrant. Anticyclonic types with wind component from the first quadrant exhibited high values of secondary, aged sea salt and dust factors. The highest contributions of the dust factor were also associated with northerly types. The linear models built for estimating the source apportionment of PM10, from aerosol chemical composition and geostrophic flow, showed positive coefficients for: westerly flows (WF) in marine factor, southerly flows (SF) in secondary and traffic factors, and shear southerly vorticities (ZS) in dust factor. Negative dependences were observed for ZS in aged sea salt factor and for SF in dust factor. The PM10 mass concentration calculated by the linear models and by the PMF model were strongly correlated. This can be very useful to determine the contribution of a specific source to PM10 in León, only by knowing some meteorological and chemical variables.
Collapse
Affiliation(s)
- Fernanda Oduber
- Department of Physics, IMARENAB University of León, León, Spain.
| | - Ana Isabel Calvo
- Department of Physics, IMARENAB University of León, León, Spain.
| | - Amaya Castro
- Department of Physics, IMARENAB University of León, León, Spain.
| | | | - Célia Alves
- Centre for Environmental and Marine Studies, Department of Environment, University of Aveiro, Aveiro, Portugal.
| | - Giulia Calzolai
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy.
| | - Silvia Nava
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy.
| | - Franco Lucarelli
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy.
| | - Teresa Nunes
- Centre for Environmental and Marine Studies, Department of Environment, University of Aveiro, Aveiro, Portugal.
| | - Joana Barata
- Centre for Environmental and Marine Studies, Department of Environment, University of Aveiro, Aveiro, Portugal.
| | - Roberto Fraile
- Department of Physics, IMARENAB University of León, León, Spain.
| |
Collapse
|
12
|
Oduber F, Calvo AI, Castro A, Blanco-Alegre C, Alves C, Barata J, Nunes T, Lucarelli F, Nava S, Calzolai G, Cerqueira M, Martín-Villacorta J, Esteves V, Fraile R. Chemical composition of rainwater under two events of aerosol transport: A Saharan dust outbreak and wildfires. Sci Total Environ 2020; 734:139202. [PMID: 32460070 DOI: 10.1016/j.scitotenv.2020.139202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/23/2020] [Accepted: 05/02/2020] [Indexed: 06/11/2023]
Abstract
A one-year campaign of joint sampling of aerosols and precipitation, carried out in León, Spain, allowed to study the impact of two special events that affected the air quality in the north of the country, on rainfall in the city: a period with wildfires and a Saharan dust intrusion. The wildfires that occurred in northern Portugal and northwestern Spain in August 2016 affected the chemistry of rainfall on 15 August 2016, causing an increase in concentrations of NH4+, Na+, Cl-, K+, Mg2+, Ca2+, SO42- and NO3- and in the concentrations of organic acids, which was reflected in the levels of soluble and insoluble organic carbon. This led to acidification of rainwater (pH = 4.8). The second precipitation event was registered between 11 and 14 February 2017, during which the rainwater was collected in four daily fractions (P1, P2, P3 and P4). The rain sample of 12 February (P2) coincided with a Saharan dust intrusion that reached northern Iberia that day. The chemical composition of P2 showed an increase in the Ca2+ (>800%), Mg2+ (71%), Cl- (62%), and SO42- (33%) concentrations, with respect to P1. The input of crustal elements to the atmosphere helped to neutralize the P2 rainwater, causing pH values higher than 6.5. Once the dust intrusion left the north of the Peninsula, the composition of rainwater P3 and P4 revealed a mixture of marine contribution with local anthropogenic emissions, as well as a decrease in ion concentrations and conductivity, and an increase in pH values.
Collapse
Affiliation(s)
- F Oduber
- Department of Physics, IMARENAB, University of León, León, Spain
| | - A I Calvo
- Department of Physics, IMARENAB, University of León, León, Spain
| | - A Castro
- Department of Physics, IMARENAB, University of León, León, Spain
| | - C Blanco-Alegre
- Department of Physics, IMARENAB, University of León, León, Spain
| | - C Alves
- Department of Environmental and Planning, CESAM, University of Aveiro, Aveiro, Portugal
| | - J Barata
- Department of Environmental and Planning, CESAM, University of Aveiro, Aveiro, Portugal
| | - T Nunes
- Department of Environmental and Planning, CESAM, University of Aveiro, Aveiro, Portugal
| | - F Lucarelli
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy
| | - S Nava
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy
| | - G Calzolai
- Department of Physics and Astronomy, University of Florence and INFN-Florence, Florence, Italy
| | - M Cerqueira
- Department of Environmental and Planning, CESAM, University of Aveiro, Aveiro, Portugal
| | | | - V Esteves
- Department of Environmental and Planning, CESAM, University of Aveiro, Aveiro, Portugal
| | - R Fraile
- Department of Physics, IMARENAB, University of León, León, Spain.
| |
Collapse
|
13
|
Blanco-Alegre C, Calvo AI, Alves C, Fialho P, Nunes T, Gomes J, Castro A, Oduber F, Coz E, Fraile R. Aethalometer measurements in a road tunnel: A step forward in the characterization of black carbon emissions from traffic. Sci Total Environ 2020; 703:135483. [PMID: 31761363 DOI: 10.1016/j.scitotenv.2019.135483] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/20/2019] [Accepted: 11/10/2019] [Indexed: 06/10/2023]
Abstract
A sampling campaign was conducted in the Liberdade Avenue tunnel (Braga, Portugal) during a week (with 56,000 vehicles) to monitor black carbon (eBC-equivalent black carbon) by means of an Aethalometer AE-31, and gaseous pollutants (CO2, CO, NOx). Inside the tunnel, the mean eBC mass concentration was 21 ± 10 μg m-3, reaching a maximum hourly value of 49.0 μg m-3. An hourly and weekday-weekend study was carried out. Regarding the Absorption Ångström exponent (AAE), a mean value of 0.97 ± 0.10 was obtained, for a source of practically pure traffic. There was a positive significant correlation between eBC and the number of light vehicles (r = 0.47; p < 0.001) and between eBC and the gaseous emissions: CO (r = 0.67; p < 0.001), CO2 (r = 0.71; p < 0.001), NO (r = 0.63; p < 0.001) and NO2 (r = 0.70; p < 0.001). The mean black carbon emission factors (EFBC) inside the tunnel were 0.31 ± 0.08 g (kg fuel)-1 and 0.11 ± 0.08 mg veh-1 km-1, similar to those found in other studies for gasoline and diesel vehicles in road tunnels.
Collapse
Affiliation(s)
- C Blanco-Alegre
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - A I Calvo
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - C Alves
- Centre for Environment and Marine Studies, Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal
| | - P Fialho
- Research Institute of Volcanology and Evaluation - IVAR, Rua da Mãe de Deus, 9500-321 Ponta Delgada, Portugal
| | - T Nunes
- Centre for Environment and Marine Studies, Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal
| | - J Gomes
- Centre for Environment and Marine Studies, Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal
| | - A Castro
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - F Oduber
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - E Coz
- Centre for Energy, Environment and Technology Research (CIEMAT), Department of the Environment, Madrid, Spain
| | - R Fraile
- Department of Physics, IMARENAB University of León, 24071 León, Spain.
| |
Collapse
|
14
|
Ramón J, Martínez-Ibernón A, Gandía-Romero J, Fraile R, Bataller R, Alcañiz M, García-Breijo E, Soto J. Characterization of electrochemical systems using potential step voltammetry. Part I: Modeling by means of equivalent circuits. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.134702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
15
|
Oduber F, Calvo AI, Blanco-Alegre C, Castro A, Nunes T, Alves C, Sorribas M, Fernández-González D, Vega-Maray AM, Valencia-Barrera RM, Lucarelli F, Nava S, Calzolai G, Alonso-Blanco E, Fraile B, Fialho P, Coz E, Prevot ASH, Pont V, Fraile R. Unusual winter Saharan dust intrusions at Northwest Spain: Air quality, radiative and health impacts. Sci Total Environ 2019; 669:213-228. [PMID: 30878930 DOI: 10.1016/j.scitotenv.2019.02.305] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 02/16/2019] [Accepted: 02/19/2019] [Indexed: 05/14/2023]
Abstract
Saharan air masses can transport high amounts of mineral dust particles and biological material to the Iberian Peninsula. During winter, this kind of events is not very frequent and usually does not reach the northwest of the Peninsula. However, between 21 and 22 February 2016 and between 22 and 23 February 2017, two exceptional events were registered in León (Spain), which severely affected air quality. An integrative approach including: i) typical synoptic conditions; ii) aerosol chemical composition; iii) particle size distributions; iv) pollen concentration; v) aerosol optical depth (AOD); vi) radiative forcing and vii) estimation of the impact of aerosols in the respiratory tract, was carried out. In the global characterization of these events, the exceedance of the PM10 daily limit value, an increase in the coarse mode and a rise in the iron concentration were observed. On the 2016 event, an AOD and extinction-related Ångström exponent clearly characteristic of desert aerosol (1.1 and 0.05, respectively) were registered. Furthermore, pollen grains not typical of flowering plants in this period were identified. The chemical analysis of the aerosol from the 2017 event allowed us to confirm the presence of the main elements associated with mineral sources (aluminum, calcium, and silica concentrations). An increase in the SO42-, NO3- and Cl- concentrations during the Saharan dust intrusion was also noted. However, in this event, there was no presence of atypical pollen types. The estimated dust radiative forcing traduced a cooling effect for surface and atmosphere during both events, corroborated by trends of radiative flux measurements. The estimated impact on the respiratory tract regions of the high levels of particulate matter during both Saharan dust intrusions showed high levels for the respirable fraction.
Collapse
Affiliation(s)
- F Oduber
- Department of Physics, IMARENAB University of León, León, Spain
| | - A I Calvo
- Department of Physics, IMARENAB University of León, León, Spain
| | - C Blanco-Alegre
- Department of Physics, IMARENAB University of León, León, Spain
| | - A Castro
- Department of Physics, IMARENAB University of León, León, Spain
| | - T Nunes
- Centre for Environmental and Marine Studies, Department of Environment, University of Aveiro, Aveiro, Portugal
| | - C Alves
- Centre for Environmental and Marine Studies, Department of Environment, University of Aveiro, Aveiro, Portugal
| | - M Sorribas
- El Arenosillo-Atmospheric Sounding Station, Atmospheric Research and Instrumentation Branch, INTA, Mazagón, Huelva, Spain
| | - D Fernández-González
- Biodiversity and Environmental Management, University of León, Spain; Institute of Atmospheric Sciences and Climate-CNR, Bologna, Italy
| | - A M Vega-Maray
- Biodiversity and Environmental Management, University of León, Spain
| | | | - F Lucarelli
- Department of Physics and Astronomy, University of Florence and I.N.F.N., Florence, Italy
| | - S Nava
- Department of Physics and Astronomy, University of Florence and I.N.F.N., Florence, Italy
| | - G Calzolai
- Department of Physics and Astronomy, University of Florence and I.N.F.N., Florence, Italy
| | - E Alonso-Blanco
- Centre for Energy, Environment and Technology Research (CIEMAT), Department of the Environment, Madrid, Spain
| | - B Fraile
- Department of Biomedicine and Biotechnology, University of Alcalá, Alcalá de Henares, Spain
| | - P Fialho
- Research Institute for Volcanology and Risk Assessment-IVAR, Ponta Delgada, Portugal
| | - E Coz
- Centre for Energy, Environment and Technology Research (CIEMAT), Department of the Environment, Madrid, Spain
| | - A S H Prevot
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen, Switzerland
| | - V Pont
- Laboratory of Aerology, National Center for Scientific Research (CNRS), University of Toulouse, Toulouse, France
| | - R Fraile
- Department of Physics, IMARENAB University of León, León, Spain.
| |
Collapse
|
16
|
Blanco-Alegre C, Calvo AI, Coz E, Castro A, Oduber F, Prévôt ASH, Močnik G, Fraile R. Quantification of source specific black carbon scavenging using an aethalometer and a disdrometer. Environ Pollut 2019; 246:336-345. [PMID: 30562655 DOI: 10.1016/j.envpol.2018.11.102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 10/22/2018] [Accepted: 11/29/2018] [Indexed: 06/09/2023]
Abstract
Aerosol black carbon (BC) is the second strongest contributor to global warming, after CO2, and it is linked to many adverse health effects. A sampling campaign of 15 months was carried out in León (Spain) in order to evaluate the scavenging of BC with an ensemble aethalometer-disdrometer. The aethalometer provides the concentration of equivalent black carbon (eBC), and the disdrometer, the raindrop size distribution. A total of seventy-five rain events were studied and in 73% of them there was an effective (eBCinitial > eBCfinal) scavenging, with a mean decrease of 48 ± 37% in long rain events (>8 h) and 39 ± 38% in short rain events. The scavenging of BC is strongly related to its source. Thus, the scavenging coefficient (SC) mean value of the BC from fossil fuel (eBCff) for short and long rain events was 5.1 10-5 and 1.3 10-5 s-1, respectively. For the BC from biomass burning (eBCbb), the SC values were 1.6 10-4 and 2.8 10-5 s-1 in short and long events, respectively. There was a significant positive correlation between the SC and the number of drops with diameters between 0.375 and 2.5 mm. Rain scavenging of eBC was analyzed depending on the air mass origin obtaining an effective scavenging for air masses from Atlantic, Arctic and Africa. A linear model (R2 = 0.72) was built to estimate the ΔeBC values with variables from an aethalometer, a disdrometer and a weather station: eBC concentration before rain, swept volume and precipitation accumulated. A Kolmogorov-Smirnov statistical test confirmed the goodness of fit of the model to the measured data.
Collapse
Affiliation(s)
- C Blanco-Alegre
- Department of Physics, IMARENAB University of León, 24071, León, Spain
| | - A I Calvo
- Department of Physics, IMARENAB University of León, 24071, León, Spain
| | - E Coz
- Centre for Energy, Environment and Technology Research (CIEMAT), Department of the Environment, Madrid, Spain
| | - A Castro
- Department of Physics, IMARENAB University of León, 24071, León, Spain
| | - F Oduber
- Department of Physics, IMARENAB University of León, 24071, León, Spain
| | - A S H Prévôt
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232, Villigen, Switzerland
| | - G Močnik
- Condensed Matter Physics Dept., Jožef Stefan Institute, 1000, Ljubljana, Slovenia
| | - R Fraile
- Department of Physics, IMARENAB University of León, 24071, León, Spain.
| |
Collapse
|
17
|
Castro A, Calvo AI, Blanco-Alegre C, Oduber F, Alves C, Coz E, Amato F, Querol X, Fraile R. Impact of the wood combustion in an open fireplace on the air quality of a living room: Estimation of the respirable fraction. Sci Total Environ 2018; 628-629:169-176. [PMID: 29432928 DOI: 10.1016/j.scitotenv.2018.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 01/25/2018] [Accepted: 02/01/2018] [Indexed: 06/08/2023]
Abstract
Presently, both in rural areas and in cities open fireplaces are still present and large quantities of wood are combusted every year. The present study aims to characterize aerosol size distribution, chemical composition and deposition in the human respiratory tract of particles emitted during the combustion of logs of oak in an open fireplace installed in the living room of a typical village house. CO2 and CO levels and aerosol size distribution have been continuously monitored and a PM10 sampler with two types of filters for chemical and microscopic analysis was also installed. The increment, between the operating periods and the indoor background, in the organic carbon and PM10 concentration due to the use of the fireplace is 15.7±0.6 (mean±standard deviation) and 58.5±6.2μgm-3, respectively. The two main polluting processes during the operation of the fireplace are the ignition with the subsequent refueling and the final cleaning of the residual ashes. In both phases mean values around 1800 particles cm-3 with CMD of 0.15μm were measured. However, while PM10 levels of 130±120μgm-3 were estimated for the ignition stage, values of 200±200μgm-3 were obtained during the final cleaning step. Assessment conducted according to ISO standard 7708:1995, demonstrated that a person who stays in a living room when an open fireplace is lit will inhale, on average, 217μgm-3 and 283μgm-3 during the ignition and the refueling stages, respectively. Subsequent refueling proved to be much less polluting. The ashes removal can also be very polluting and dangerous to health if there are hidden small incandescent embers among the ashes (estimated PM10 of 132μgm-3), reaching a CO2 level of 1940ppm and a dangerous level of CO of 132ppm.
Collapse
Affiliation(s)
- A Castro
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - A I Calvo
- Department of Physics, IMARENAB University of León, 24071 León, Spain.
| | - C Blanco-Alegre
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - F Oduber
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| | - C Alves
- Centre for Environmental and Marine Studies (CESAM), Department of Environment and Planning, University of Aveiro, Aveiro 3810-193, Portugal
| | - E Coz
- Centre for Energy, Environment and Technology Research (CIEMAT), Department of the Environment, 28040, Madrid, Spain
| | - F Amato
- Institute of Environmental Assessment and Water Research, Spanish Research Council (IDAEA-CSIC), 08034 Barcelona, Spain
| | - X Querol
- Institute of Environmental Assessment and Water Research, Spanish Research Council (IDAEA-CSIC), 08034 Barcelona, Spain
| | - R Fraile
- Department of Physics, IMARENAB University of León, 24071 León, Spain
| |
Collapse
|
18
|
Alonso-Blanco E, Castro A, Calvo AI, Pont V, Mallet M, Fraile R. Wildfire smoke plumes transport under a subsidence inversion: Climate and health implications in a distant urban area. Sci Total Environ 2018; 619-620:988-1002. [PMID: 29734644 DOI: 10.1016/j.scitotenv.2017.11.142] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 11/12/2017] [Accepted: 11/13/2017] [Indexed: 06/08/2023]
Affiliation(s)
- Elisabeth Alonso-Blanco
- Centre for Energy, Environment and Technology Research (CIEMAT), Department of the Environment, 28040 Madrid, Spain
| | - Amaya Castro
- Department of Physics (IMARENAB), University of León, 24071 León, Spain
| | - Ana I Calvo
- Department of Physics (IMARENAB), University of León, 24071 León, Spain
| | - Veronique Pont
- Laboratoire d'Aérologie/OMP, UMR 5560, Université de Toulouse III, CNRS-UPS, 14, av. E. Belin, 31400 Toulouse, France
| | - Marc Mallet
- Laboratoire d'Aérologie/OMP, UMR 5560, Université de Toulouse III, CNRS-UPS, 14, av. E. Belin, 31400 Toulouse, France
| | - Roberto Fraile
- Department of Physics (IMARENAB), University of León, 24071 León, Spain.
| |
Collapse
|
19
|
Fernández-Guisuraga JM, Castro A, Alves C, Calvo A, Alonso-Blanco E, Blanco-Alegre C, Rocha A, Fraile R. Nitrogen oxides and ozone in Portugal: trends and ozone estimation in an urban and a rural site. Environ Sci Pollut Res Int 2016; 23:17171-17182. [PMID: 27215985 DOI: 10.1007/s11356-016-6888-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 05/11/2016] [Indexed: 06/05/2023]
Abstract
This study provides an analysis of the spatial distribution and trends of NO, NO2 and O3 concentrations in Portugal between 1995 and 2010. Furthermore, an estimation model for daily ozone concentrations was developed for an urban and a rural site. NO concentration showed a significant decreasing trend in most urban stations. A decreasing trend in NO2 is only observed in the stations with less influence from emissions of primary NO2. Several stations showed a significant upward trend in O3 as a result of the decrease in the NO/NO2 ratio. In the northern rural region, ozone showed a strong correlation with wind direction, highlighting the importance of long-range transport. In the urban site, most of the variance is explained by the NO2/NOX ratio. The results obtained by the ozone estimation model in the urban site fit 2013 observed data. In the rural site, the estimated ozone during extreme events agrees with observed concentration.
Collapse
Affiliation(s)
| | - Amaya Castro
- Department of Physics (IMARENAB), University of León, León, 24071, Spain
| | - Célia Alves
- Centre for Environment and Marine Studies, Department of Environment, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Ana Calvo
- Department of Physics (IMARENAB), University of León, León, 24071, Spain
| | - Elisabeth Alonso-Blanco
- Centre for Energy, Environmental and Technological Research (CIEMAT), Department of Environment, 28040, Madrid, Spain
| | | | - Alfredo Rocha
- Centre for Environment and Marine Studies, Department of Physics, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Roberto Fraile
- Department of Physics (IMARENAB), University of León, León, 24071, Spain.
| |
Collapse
|
20
|
Castro A, Calvo AI, Alves C, Alonso-Blanco E, Coz E, Marques L, Nunes T, Fernández-Guisuraga JM, Fraile R. Indoor aerosol size distributions in a gymnasium. Sci Total Environ 2015; 524-525:178-86. [PMID: 25897726 DOI: 10.1016/j.scitotenv.2015.03.118] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 03/02/2015] [Accepted: 03/27/2015] [Indexed: 05/27/2023]
Abstract
In this study, an indoor/outdoor monitoring program was carried out in a gymnasium at the University of Leon, Spain. The main goal was a characterization of aerosol size distributions in a university gymnasium under different conditions and sports activities (with and without magnesia alba) and the study of the mass fraction deposited in each of the parts of the respiratory tract. The aerosol particles were measured in 31 discrete channels (size ranges) using a laser spectrometer probe. Aerosol size distributions were studied under different conditions: i) before sports activities, ii) activities without using magnesia alba, iii) activities using magnesia alba, iv) cleaning procedures, and v) outdoors. The aerosol refractive index and density indoors were estimated from the aerosol composition: 1.577-0.003i and 2.055 g cm(-3), respectively. Using the estimated density, the mass concentration was calculated, and the evolution of PM1, PM2.5 and PM10 for different activities was assessed. The quality of the air in the gymnasium was strongly influenced by the use of magnesia alba (MgCO3) and the number of gymnasts who were training. Due to the climbing chalk and the constant process of resuspension, average PM10 concentrations of over 440 μg m(-3) were reached. The maximum daily concentrations ranged from 500 to 900 μg m(-3). Particle size determines the place in the respiratory tract where the deposition occurs. For this reason, the inhalable, thoracic, tracheobronchial and respirable fractions were assessed for healthy adults and high risk people, according to international standards. The estimations show that, for healthy adults, up to 300 μg m(-3) can be retained by the trachea and bronchi, and 130 μg m(-3) may reach the alveolar region. The different physical activities and the attendance rates in the sports facility have a significant influence on the concentration and size distributions observed.
Collapse
Affiliation(s)
- Amaya Castro
- Department of Physics (IMARENAB), University of León, 24071 León, Spain
| | - Ana I Calvo
- Department of Physics (IMARENAB), University of León, 24071 León, Spain
| | - Célia Alves
- Centre for Environment and Marine Studies, Department of Environment, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Elisabeth Alonso-Blanco
- Centre for Energy, Environment and Technology Research (CIEMAT), Department of Environment, 28040 Madrid, Spain
| | - Esther Coz
- Centre for Energy, Environment and Technology Research (CIEMAT), Department of Environment, 28040 Madrid, Spain
| | - Liliana Marques
- Centre for Environment and Marine Studies, Department of Environment, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Teresa Nunes
- Centre for Environment and Marine Studies, Department of Environment, University of Aveiro, 3810-193 Aveiro, Portugal
| | | | - Roberto Fraile
- Department of Physics (IMARENAB), University of León, 24071 León, Spain.
| |
Collapse
|
21
|
Alves C, Calvo AI, Marques L, Castro A, Nunes T, Coz E, Fraile R. Particulate matter in the indoor and outdoor air of a gymnasium and a fronton. Environ Sci Pollut Res Int 2014; 21:12390-402. [PMID: 24938814 DOI: 10.1007/s11356-014-3168-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 06/05/2014] [Indexed: 05/24/2023]
Abstract
An indoor/outdoor monitoring programme of PM10 was carried out in two sports venues (a fronton and a gymnasium). Levels always below 50 μg m(-3) were obtained in the fronton and outdoor air. Due to the climbing chalk and the constant process of resuspension, concentrations above 150 μg m(-3) were registered in the gymnasium. The chalk dust contributed to CO3 (2-) concentrations of 32 ± 9.4 μg m(-3) in this sports facility, which represented, on average, 18 % of the PM10 mass. Here, the carbonate levels were 128 times higher than those registered outdoors. Much lower concentrations, around 1 μg m(-3), were measured in the fronton. The chalk dust is also responsible for the high Mg(2+) concentrations in the gym (4.7 ± 0.89 μg m(-3)), unfolding a PM10 mass fraction of 2.7 %. Total carbon accounted for almost 30 % of PM10 in both indoor spaces. Aerosol size distributions were bimodal and revealed a clear dependence on physical activities and characteristics of the sports facilities. The use of climbing chalk in the gymnasium contributed significantly to the coarse mode. The average geometric mean diameter, geometric standard deviation and total number of coarse particles were 0.77 μm, 2.79 cm(-3) and 28 cm(-3), respectively.
Collapse
Affiliation(s)
- Célia Alves
- Centre for Environment and Marine Studies, Department of Environment, University of Aveiro, 3810-193, Aveiro, Portugal,
| | | | | | | | | | | | | |
Collapse
|
22
|
Gutiérrez-Arriola JM, Osma-Ruiz V, Sáenz-Lechón N, Godino-Llorente JI, Fraile R, Arias-Londoño JD. Objective measurements to evaluate glottal space segmentation from laryngeal images. Annu Int Conf IEEE Eng Med Biol Soc 2013; 2012:5396-9. [PMID: 23367149 DOI: 10.1109/embc.2012.6347214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Objective evaluation of the results of medical image segmentation is a known problem. Applied to the task of automatically detecting the glottal area from laryngeal images, this paper proposes a new objective measurement to evaluate the quality of a segmentation algorithm by comparing with the results given by a human expert. The new figure of merit is called Area Index, and its effectiveness is compared with one of the most used figures of merit found in the literature: the Pratt Index. Results over 110 laryngeal images presented high correlations between both indexes, demonstrating that the proposed measure is comparable to the Pratt Index and it is a good indicator of the segmentation quality.
Collapse
Affiliation(s)
- J M Gutiérrez-Arriola
- Dept. of Ingeniería de Circuitos ySistemas, Universidad Politécnica de Madrid, Ctra. Valencia, km.7, 28031,Madrid, Spain.
| | | | | | | | | | | |
Collapse
|
23
|
Gil-García R, Fraile R, Donnadieu B, Madariaga G, Januskaitis V, Rovira J, González L, Borrás J, Arnáiz FJ, García-Tojal J. Desulfurization processes of thiosemicarbazonecopper(ii) derivatives in acidic and basic aqueous media. NEW J CHEM 2013. [DOI: 10.1039/c3nj00321c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
24
|
Alonso-Blanco E, Calvo AI, Fraile R, Castro A. The influence of wildfires on aerosol size distributions in rural areas. ScientificWorldJournal 2012; 2012:735697. [PMID: 22629191 PMCID: PMC3353560 DOI: 10.1100/2012/735697] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 12/08/2011] [Indexed: 11/17/2022] Open
Abstract
The number of particles and their size distributions were measured in a rural area, during the summer, using a PCASP-X. The aim was to study the influence of wildfires on particle size distributions. The comparative studies carried out reveal an average increase of around ten times in the number of particles in the fine mode, especially in sizes between 0.10 and 0.14 μm, where the increase is of nearly 20 times. An analysis carried out at three different points in time—before, during, and after the passing of the smoke plume from the wildfires—shows that the mean geometric diameter of the fine mode in the measurements affected by the fire is smaller than the one obtained in the measurements carried out immediately before and after (0.14 μm) and presents average values of 0.11 μm.
Collapse
Affiliation(s)
- E Alonso-Blanco
- Department of Physics, IMARENAB, University of León, León 24071, Spain
| | | | | | | |
Collapse
|
25
|
Fernández-Raga M, Tomás C, Fraile R. Human mortality seasonality in Castile-León, Spain, between 1980 and 1998: the influence of temperature, pressure and humidity. Int J Biometeorol 2010; 54:379-392. [PMID: 20107841 DOI: 10.1007/s00484-009-0289-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2008] [Revised: 10/25/2009] [Accepted: 11/27/2009] [Indexed: 05/28/2023]
Abstract
This study was carried out in the region of Castile and Leon, Spain, from 1980 to 1998 and analyzes the relationship between the number of monthly deaths caused by cardiovascular, respiratory and digestive diseases and three meteorological variables: temperature, pressure and humidity. One of the innovations in this study is the application of principal component analysis in a way that differs from its usual application: one single series representing the whole region was constructed for each meteorological variable from the series of eight weather stations. Annual and seasonal mortality trends were also studied. Cardiovascular diseases are the leading cause of death in Castile and Leon. The mortality related to cardiovascular, respiratory and digestive systems shows a statistically significant rising trend across the study period (an annual increase of 6, 16 and 4 per thousand, respectively). The pressure at which mortality is lowest is approximately the same for all causes of death (about 915 hPa), but temperature values vary greatly (16.8-19.7 degrees C for the mean, 10.9-18.1 degrees C for the minimum, and 24.1-27.2 degrees C for the maximum temperature). The most comfortable temperatures for patients with cardiovascular diseases (16.8 degrees C) are apparently lower than those for patients with respiratory diseases (18.1 degrees C), which are, in turn, lower than in the case of diseases of the digestive system (19.7 degrees C). Finally, the optimal humidity for patients with respiratory diseases is the lowest (24%) among the diseases, and the highest (51%) corresponds to diseases of the digestive system, while the optimal relative humidity for the cardiovascular system is 45%.
Collapse
Affiliation(s)
- María Fernández-Raga
- Departamento de Física, Facultad de CC Biológicas y Ambientales, Universidad de León, 24071, León, Spain
| | | | | |
Collapse
|
26
|
Calvo AI, Pont V, Castro A, Mallet M, Palencia C, Roger JC, Dubuisson P, Fraile R. Radiative forcing of haze during a forest fire in Spain. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd012172] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
27
|
Fraile R, Sáenz-Lechón N, Godino-Llorente JI, Osma-Ruiz V, Fredouille C. Automatic detection of laryngeal pathologies in records of sustained vowels by means of mel-frequency cepstral coefficient parameters and differentiation of patients by sex. Folia Phoniatr Logop 2009; 61:146-52. [PMID: 19571549 DOI: 10.1159/000219950] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Mel-frequency cepstral coefficients (MFCC) have traditionally been used in speaker identification applications. Their use has been extended to speech quality assessment for clinical applications during the last few years. While the significance of such parameters for such an application may not seem clear at first thought, previous research has demonstrated their robustness and statistical significance and, at the same time, their close relationship with glottal noise measurements. This paper includes a review of this parameterization scheme and it analyzes its performance for voice analysis when patients are differentiated by sex. While it is of common use for establishing normative values for traditional voice descriptors (e.g. pitch, jitter, formants), differentiation by sex had not been tested yet for cepstral analysis of voice with clinical purposes. This paper shows that the automatic detection of laryngeal pathology on voice records based on MFCC can significantly improve its performance by means of this prior differentiation by sex.
Collapse
Affiliation(s)
- R Fraile
- Circuits and Systems Engineering Department, EUIT Telecomunicación, Universidad Politécnica de Madrid, Madrid, Spain.
| | | | | | | | | |
Collapse
|
28
|
González Parrado Z, Valencia Barrera RM, Fuertes Rodríguez CR, Vega Maray AM, Pérez Romero R, Fraile R, Fernández González D. Alternative statistical methods for interpreting airborne Alder (Alnus glutimosa (L.) Gaertner) pollen concentrations. Int J Biometeorol 2009; 53:1-9. [PMID: 18853202 DOI: 10.1007/s00484-008-0184-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Accepted: 09/03/2008] [Indexed: 05/12/2023]
Abstract
This paper reports on the behaviour of Alnus glutinosa (alder) pollen grains in the atmosphere of Ponferrada (León, NW Spain) from 1995 to 2006. The study, which sought to determine the effects of various weather-related parameters on Alnus pollen counts, was performed using a volumetric method. The main pollination period for this taxon is January-February. Alder pollen is one of the eight major airborne pollen allergens found in the study area. An analysis was made of the correlation between pollen counts and major weather-related parameters over each period. In general, the strongest positive correlation was with temperature, particularly maximum temperature. During each period, peak pollen counts occurred when the maximum temperature fell within the range 9 degrees C-14 degrees C. Finally, multivariate analysis showed that the parameter exerting the greatest influence was temperature, a finding confirmed by Spearman correlation tests. Principal components analysis suggested that periods with high pollen counts were characterised by high maximum temperature, low rainfall and an absolute humidity of around 6 g m(-3). Use of this type of analysis in conjunction with other methods is essential for obtaining an accurate record of pollen-count variations over a given period.
Collapse
Affiliation(s)
- Zulima González Parrado
- Department of Biodiversity and Environmental Management, University of León, Campus de Vegazana s/n, 24071, León, Spain.
| | | | | | | | | | | | | |
Collapse
|
29
|
Fraile R, Hancock ER. Spectral Modes of Facial Needle-Maps. Pattern Recognition and Image Analysis 2007. [DOI: 10.1007/978-3-540-72847-4_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
30
|
Vega-Maray AM, Valencia-Barrera R, Fernandez-Gonzalez D, Fraile R. Urticaceae pollen concentration in the atmosphere of North Western Spain. Ann Agric Environ Med 2003; 10:249-255. [PMID: 14677920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Plants of the Urticaceae family can develop into a pest on soils enriched with nitrogen. Urticaceae pollen is a biohazard because it elicits severe pollinosis. Pollen grains were sampled by using a Lanzoni seven-day-recording trap from February 1995-December 2000 in the atmosphere of the city of Ponferrada (Leon, North Western Spain). The Spearman test was used to analyse the statistical correlation between Urticaceae pollen and certain meteorological factors in different main pollination periods. Maximum values are reached in June and July, minimum levels are recorded in January and December. The parameters bearing the greatest positive influence on the occurrence of Urticaceae pollen grains are: temperature (maximum, minimum and mean), humidity (absolute, wet-bulb temperature, dew point and mixing ratio) and south western wind direction; negative parameters are: relative humidity, rainfall and period without wind. The highest correlation coefficients were obtained with temperature and wet-bulb. Absolute humidity and wet-bulb temperature yielded better correlation than relative humidity; hence, these two parameters must be included in this type of study. The use of one main pollination period or another in statistical analysis has an influence on the coefficient value. The behaviour of the pollen grains in the atmosphere during the year also influences the results.
Collapse
Affiliation(s)
- Ana Maria Vega-Maray
- Departamento de Biologia Vegetal (Botanica), Facultad de Ciencias Biologicas y Ambientales, Universidad de Leon. Campus de Vegazana, 24071 Leon, Spain.
| | | | | | | |
Collapse
|
31
|
Narro M, Fraile R, Sáez L, Arribas J. Síncope. Diagnóstico diferencial. Semergen 2001. [DOI: 10.1016/s1138-3593(01)73972-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
32
|
|
33
|
Ramirez AJ, Fernández AJ, Fraile R. Lead, copper and zinc in atmospheric and fluvial particulates from the Caracas Valley, Venezuela. Environ Geochem Health 1994; 16:129-136. [PMID: 24197207 DOI: 10.1007/bf01747909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/20/1993] [Indexed: 06/02/2023]
Abstract
The atmospheric particulates from the Caracus Valley in Venezuela and the fluvial particulates transported by the Tuy River into the Caribbean sea have been evaluated for Pb, Cu and Zn with the purpose of determining the contamination levels in the study area. The atmospheric particulate samples were collected in the city of Caracas using a low volume sampler whereas the fluvial particulate were collected at the mouth of the Tuy River. The particulate samples were analysed by flame or graphite furnace atomic absorption spectrometry depending upon the concentration levels of the heavy metal under study. The results obtained for the fluvial particulates enabled estimates to be made of the total anthropogenic flux of Cu (383 ton year(-1)), Pb (528 ton year(-1)) and Zn (865 ton year(-1)). These results yield annual per capita inputs for Cu (96 g),Pb (132 g) and Zn (216 g) which greatly exceed those from global anthropogenic emissions. The weighted average concentration of Pb (1.13 %) found in the atmospheric particulates was much higher than those for Cu (140 mg kg(-1)) and Zn (200 mg kg(-1)) and reflects the high motor car traffic in the Caracas Valley. The anthropogenic/natural ratios estimated in this study were as follows: 2.6 for Pb; 1.5 for Cu and 1.5 for Zn. This indicates that anthropogenic inputs for Cu, Pb, and Zn in the study area exceed those from natural sources, cars being the major source for Pb and industrial activities the major sources for Cu and Zn.
Collapse
Affiliation(s)
- A J Ramirez
- Instituto de Ciencias de la Tierra, Facultad de Ciencias, Universidad Central de Venezuela, P.O. Box 3895, 1010-A, Caracas, Venezuela
| | | | | |
Collapse
|
34
|
Fraile R, de Benzo ZA, Velosa M. Determination of cadmium in urine by platform ET-AAS independent of matrix composition. ACTA ACUST UNITED AC 1992. [DOI: 10.1007/bf00322382] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
35
|
Affiliation(s)
- Z A de Benzo
- Centro de Quimica, Instituto Venezolano de Investigaciones Cientificas, IVIC, Caracas
| | | | | | | |
Collapse
|
36
|
Buroker T, Samson M, Correa J, Fraile R, Vaitkevicius VK. Hepatic artery infusion of 5-FUDR after prior systemic 5-fluorouracil. Cancer Treat Rep 1976; 60:1277-9. [PMID: 138480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Twenty-one patients with disseminated colon carcinoma and clinically significant liver metastases were treated with 5-FUDR via hepatic artery infusion (HAI). All patients had previously received systemic chemotherapy consisting of either 5-fluorouracil aone or in combination with other agents. At the time of the initiation of the HAI, clinical disease in all patients was progressing. A PR of hepatic metastases was noted in eight patients (35%) with a median and mean duration of response of 4.5 and 5.0 months respectively. The median and mean survival from the start of HAI for responders was 8.0 and 9.0 months and for nonresponders was 1.0 and 1.6 months respectively. It appears that a significant response rate can be achieved with HAI of 5-FUDR in spite of previous exposure to fluorinated pyrimidines.
Collapse
|