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Viitanen AK, Kallonen K, Kukko K, Kanerva T, Saukko E, Hussein T, Hämeri K, Säämänen A. Technical control of nanoparticle emissions from desktop 3D printing. Indoor Air 2021; 31:1061-1071. [PMID: 33647162 DOI: 10.1111/ina.12791] [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: 11/23/2020] [Accepted: 12/24/2020] [Indexed: 05/05/2023]
Abstract
Material extrusion (ME) desktop 3D printing is known to strongly emit nanoparticles (NP), and the need for risk management has been recognized widely. Four different engineering control measures were studied in real-life office conditions by means of online NP measurements and indoor aerosol modeling. The studied engineering control measures were general ventilation, local exhaust ventilation (LEV), retrofitted enclosure, and retrofitted enclosure with LEV. Efficiency between different control measures was compared based on particle number and surface area (SA) concentrations from which SA concentration was found to be more reliable. The study found out that for regular or long-time use of ME desktop 3D printers, the general ventilation is not sufficient control measure for NP emissions. Also, the LEV with canopy hood attached above the 3D printer did not control the emission remarkably and successful position of the hood in relation to the nozzle was found challenging. Retrofitted enclosure attached to the LEV reduced the NP emissions 96% based on SA concentration. Retrofitted enclosure is nearly as efficient as enclosure attached to the LEV (reduction of 89% based on SA concentration) but may be considered more practical solution than enclosure with LEV.
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Affiliation(s)
| | - Kimmo Kallonen
- Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, Helsinki, Finland
- Helsinki Institute of Physics (HIP), University of Helsinki, Helsinki, Finland
| | - Kirsi Kukko
- Department of Mechanical Engineering, Aalto University, Espoo, Finland
| | - Tomi Kanerva
- Finnish Institute of Occupational Health, Helsinki, Finland
| | | | - Tareq Hussein
- Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, Helsinki, Finland
- Department of Physics, School of Science, University of Jordan, Amman, Jordan
| | - Kaarle Hämeri
- Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, Helsinki, Finland
| | - Arto Säämänen
- Finnish Institute of Occupational Health, Helsinki, Finland
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Koivisto AJ, Kling KI, Hänninen O, Jayjock M, Löndahl J, Wierzbicka A, Fonseca AS, Uhrbrand K, Boor BE, Jiménez AS, Hämeri K, Maso MD, Arnold SF, Jensen KA, Viana M, Morawska L, Hussein T. Source specific exposure and risk assessment for indoor aerosols. Sci Total Environ 2019; 668:13-24. [PMID: 30851679 DOI: 10.1016/j.scitotenv.2019.02.398] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [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: 01/03/2019] [Revised: 02/20/2019] [Accepted: 02/25/2019] [Indexed: 05/19/2023]
Abstract
Poor air quality is a leading contributor to the global disease burden and total number of deaths worldwide. Humans spend most of their time in built environments where the majority of the inhalation exposure occurs. Indoor Air Quality (IAQ) is challenged by outdoor air pollution entering indoors through ventilation and infiltration and by indoor emission sources. The aim of this study was to understand the current knowledge level and gaps regarding effective approaches to improve IAQ. Emission regulations currently focus on outdoor emissions, whereas quantitative understanding of emissions from indoor sources is generally lacking. Therefore, specific indoor sources need to be identified, characterized, and quantified according to their environmental and human health impact. The emission sources should be stored in terms of relevant metrics and statistics in an easily accessible format that is applicable for source specific exposure assessment by using mathematical mass balance modelings. This forms a foundation for comprehensive risk assessment and efficient interventions. For such a general exposure assessment model we need 1) systematic methods for indoor aerosol emission source assessment, 2) source emission documentation in terms of relevant a) aerosol metrics and b) biological metrics, 3) default model parameterization for predictive exposure modeling, 4) other needs related to aerosol characterization techniques and modeling methods. Such a general exposure assessment model can be applicable for private, public, and occupational indoor exposure assessment, making it a valuable tool for public health professionals, product safety designers, industrial hygienists, building scientists, and environmental consultants working in the field of IAQ and health.
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Affiliation(s)
- Antti Joonas Koivisto
- National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark.
| | - Kirsten Inga Kling
- National Centre for Nano Fabrication and Characterization, Technical University of Denmark, Fysikvej 307, 2800 Kgs. Lyngby, Denmark
| | - Otto Hänninen
- National Institute for Health and Welfare (THL), Kuopio, Finland
| | | | - Jakob Löndahl
- Division of Ergonomics and Aerosol Technology, Department of Design Sciences, Lund University, Box 118, SE-22100 Lund, Sweden
| | - Aneta Wierzbicka
- Division of Ergonomics and Aerosol Technology, Department of Design Sciences, Lund University, Box 118, SE-22100 Lund, Sweden
| | - Ana Sofia Fonseca
- National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark
| | - Katrine Uhrbrand
- National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark
| | - Brandon E Boor
- Lyles School of Civil Engineering, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN 47907, United States; Ray W. Herrick Laboratories, Center for High Performance Buildings, Purdue University, 177 South Russell Street, West Lafayette, IN 47907, United States
| | - Araceli Sánchez Jiménez
- Centre for Human Exposure Science (CHES), Institute of Occupational Medicine (IOM), Research Avenue North, Riccarton, Edinburgh EH14 4AP, UK
| | - Kaarle Hämeri
- University of Helsinki, Institute for Atmospheric and Earth System Research (INAR), PL 64, FI-00014 Helsinki, Finland
| | - Miikka Dal Maso
- Aerosol Physics, Faculty of Natural Science, Tampere University of Technology, Tampere, Finland
| | - Susan F Arnold
- Division of Environmental Health Sciences, School of Public Health, University of Minnesota, Minneapolis, MN, United States
| | - Keld A Jensen
- National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark
| | - Mar Viana
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC), C/ Jordi Girona 18, 08034 Barcelona, Spain
| | - Lidia Morawska
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Qld, Australia
| | - Tareq Hussein
- University of Helsinki, Institute for Atmospheric and Earth System Research (INAR), PL 64, FI-00014 Helsinki, Finland; The University of Jordan, Department of Physics, Amman 11942, Jordan
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Hyytiäinen HK, Jayaprakash B, Kirjavainen PV, Saari SE, Holopainen R, Keskinen J, Hämeri K, Hyvärinen A, Boor BE, Täubel M. Crawling-induced floor dust resuspension affects the microbiota of the infant breathing zone. Microbiome 2018; 6:25. [PMID: 29394954 PMCID: PMC5797336 DOI: 10.1186/s40168-018-0405-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 01/18/2018] [Indexed: 05/21/2023]
Abstract
BACKGROUND Floor dust is commonly used for microbial determinations in epidemiological studies to estimate early-life indoor microbial exposures. Resuspension of floor dust and its impact on infant microbial exposure is, however, little explored. The aim of our study was to investigate how floor dust resuspension induced by an infant's crawling motion and an adult walking affects infant inhalation exposure to microbes. RESULTS We conducted controlled chamber experiments with a simplified mechanical crawling infant robot and an adult volunteer walking over carpeted flooring. We applied bacterial 16S rRNA gene sequencing and quantitative PCR to monitor the infant breathing zone microbial content and compared that to the adult breathing zone and the carpet dust as the source. During crawling, fungal and bacterial levels were, on average, 8- to 21-fold higher in the infant breathing zone compared to measurements from the adult breathing zone. During walking experiments, the increase in microbial levels in the infant breathing zone was far less pronounced. The correlation in rank orders of microbial levels in the carpet dust and the corresponding infant breathing zone sample varied between different microbial groups but was mostly moderate. The relative abundance of bacterial taxa was characteristically distinct in carpet dust and infant and adult breathing zones during the infant crawling experiments. Bacterial diversity in carpet dust and the infant breathing zone did not correlate significantly. CONCLUSIONS The microbiota in the infant breathing zone differ in absolute quantitative and compositional terms from that of the adult breathing zone and of floor dust. Crawling induces resuspension of floor dust from carpeted flooring, creating a concentrated and localized cloud of microbial content around the infant. Thus, the microbial exposure of infants following dust resuspension is difficult to predict based on common house dust or bulk air measurements. Improved approaches for the assessment of infant microbial exposure, such as sampling at the infant breathing zone level, are needed.
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Affiliation(s)
- Heidi K. Hyytiäinen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
| | | | - Pirkka V. Kirjavainen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
- Department of Clinical Nutrition, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Sampo E. Saari
- Aerosol Physics Unit, Faculty of Natural Sciences, Tampere University of Technology, Tampere, Finland
- VTT Technical Research Centre of Finland, Tampere, Finland
| | - Rauno Holopainen
- Finnish Institute of Occupational Health, Helsinki, Finland
- Oulu University of Applied Sciences, Oulu, Finland
| | - Jorma Keskinen
- Aerosol Physics Unit, Faculty of Natural Sciences, Tampere University of Technology, Tampere, Finland
| | - Kaarle Hämeri
- Division of Atmospheric Sciences, Department of Physics, University of Helsinki, Helsinki, Finland
| | - Anne Hyvärinen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
| | - Brandon E. Boor
- Lyles School of Civil Engineering, Purdue University, West Lafayette, IN USA
- Ray W. Herrick Laboratories, Center for High Performance Buildings, Purdue University, West Lafayette, IN USA
| | - Martin Täubel
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
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Wu T, Täubel M, Holopainen R, Viitanen AK, Vainiotalo S, Tuomi T, Keskinen J, Hyvärinen A, Hämeri K, Saari SE, Boor BE. Infant and Adult Inhalation Exposure to Resuspended Biological Particulate Matter. Environ Sci Technol 2018; 52:237-247. [PMID: 29144737 DOI: 10.1021/acs.est.7b04183] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Human-induced resuspension of floor dust is a dynamic process that can serve as a major indoor source of biological particulate matter (bioPM). Inhalation exposure to the microbial and allergenic content of indoor dust is associated with adverse and protective health effects. This study evaluates infant and adult inhalation exposures and respiratory tract deposited dose rates of resuspended bioPM from carpets. Chamber experiments were conducted with a robotic crawling infant and an adult performing a walking sequence. Breathing zone (BZ) size distributions of resuspended fluorescent biological aerosol particles (FBAPs), a bioPM proxy, were monitored in real-time. FBAP exposures were highly transient during periods of locomotion. Both crawling and walking delivered a significant number of resuspended FBAPs to the BZ, with concentrations ranging from 0.5 to 2 cm-3 (mass range: ∼50 to 600 μg/m3). Infants and adults are primarily exposed to a unimodal FBAP size distribution between 2 and 6 μm, with infants receiving greater exposures to super-10 μm FBAPs. In just 1 min of crawling or walking, 103-104 resuspended FBAPs can deposit in the respiratory tract, with an infant receiving much of their respiratory tract deposited dose in their lower airways. Per kg body mass, an infant will receive a nearly four times greater respiratory tract deposited dose of resuspended FBAPs compared to an adult.
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Affiliation(s)
- Tianren Wu
- Lyles School of Civil Engineering, Purdue University , 550 Stadium Mall Drive, West Lafayette, Indiana 47907, United States
- Ray W. Herrick Laboratories, Center for High Performance Buildings, Purdue University , 177 South Russell Street, West Lafayette, Indiana 47907, United States
| | - Martin Täubel
- National Institute for Health and Welfare , P.O. Box 95, Kuopio, FI 70701, Finland
| | - Rauno Holopainen
- Oulu University of Applied Sciences , P.O. Box 222, Oulu, FI 90101, Finland
| | - Anna-Kaisa Viitanen
- Finnish Institute of Occupational Health , P.O. Box 40, Helsinki, FI 00250, Finland
| | - Sinikka Vainiotalo
- Finnish Institute of Occupational Health , P.O. Box 40, Helsinki, FI 00250, Finland
| | - Timo Tuomi
- Finnish Institute of Occupational Health , P.O. Box 40, Helsinki, FI 00250, Finland
| | - Jorma Keskinen
- Department of Physics, Tampere University of Technology , P.O. Box 692, Tampere, FI 33101, Finland
| | - Anne Hyvärinen
- National Institute for Health and Welfare , P.O. Box 95, Kuopio, FI 70701, Finland
| | - Kaarle Hämeri
- Department of Physics, University of Helsinki , P.O. Box 64, Helsinki, FI 00014, Finland
| | - Sampo E Saari
- Department of Physics, Tampere University of Technology , P.O. Box 692, Tampere, FI 33101, Finland
| | - Brandon E Boor
- Lyles School of Civil Engineering, Purdue University , 550 Stadium Mall Drive, West Lafayette, Indiana 47907, United States
- Ray W. Herrick Laboratories, Center for High Performance Buildings, Purdue University , 177 South Russell Street, West Lafayette, Indiana 47907, United States
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Viitanen AK, Uuksulainen S, Koivisto AJ, Hämeri K, Kauppinen T. Workplace Measurements of Ultrafine Particles—A Literature Review. Ann Work Expo Health 2017; 61:749-758. [DOI: 10.1093/annweh/wxx049] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 06/08/2017] [Indexed: 01/29/2023] Open
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Maragkidou A, Arar S, Al-Hunaiti A, Ma Y, Harrad S, Jaghbeir O, Faouri D, Hämeri K, Hussein T. Occupational health risk assessment and exposure to floor dust PAHs inside an educational building. Sci Total Environ 2017; 579:1050-1056. [PMID: 27887828 DOI: 10.1016/j.scitotenv.2016.11.055] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [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: 07/10/2016] [Revised: 11/05/2016] [Accepted: 11/09/2016] [Indexed: 05/22/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) settled in floor dust play an important role in human health. Although many studies investigated occupational exposure to PAHs, no attempts have been made to report PAHs concentrations as well as their health risk assessment inside an educational building in Jordan. Therefore, the main objective of this study is to report the PAHs concentrations in floor dust and evaluate their exposure and health risk inside the Department of Physics of the University of Jordan. The total PAHs concentrations ranged from 714 to 5246ng/g. The high concentrations were observed inside some offices, where tobacco smoking took place. One of those offices was previously renovated and some petrochemical liquids were used to remove the remaining glue from a previous carpet. Interestingly, the PAHs inside these offices were higher than those reported inside lecture rooms and the workshop area, where extensive activates of heavy machinery and use of petroleum products (such as lubricating oils). This implies that the health effects of exposure to tobacco smoking inside small micro-environmental places that are poorly ventilated can be very harmful. We also made a simple exposure and health risk assessment for the ingested dust (hand-to-mouth) by calculating the Estimated Daily Intake (EDI) and benzo(a)pyrene equivalent carcinogenic power (BaPE). The total EDI was less than 3.75ng/kg-bw/day whereas the BaPE was less than 385ng/g. These values are lower than what was reported in some previous studies in Europe and Asia.
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Affiliation(s)
- Androniki Maragkidou
- University of Helsinki, Division of Atmospheric Sciences, PL 48, FI-00014 Helsinki, Finland
| | - Sharif Arar
- The University of Jordan, Department of Chemistry, Amman 11942, Jordan
| | | | - Yuning Ma
- University of Birmingham, School of Geography, Earth & Environmental Sciences, Division of Environmental Health & Risk Management, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Stuart Harrad
- University of Birmingham, School of Geography, Earth & Environmental Sciences, Division of Environmental Health & Risk Management, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Omar Jaghbeir
- The University of Jordan, Department of Physics, Amman 11942, Jordan
| | - Dina Faouri
- The University of Jordan, Department of Physics, Amman 11942, Jordan
| | - Kaarle Hämeri
- University of Helsinki, Division of Atmospheric Sciences, PL 48, FI-00014 Helsinki, Finland
| | - Tareq Hussein
- The University of Jordan, Department of Physics, Amman 11942, Jordan.
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Fonseca AS, Maragkidou A, Viana M, Querol X, Hämeri K, de Francisco I, Estepa C, Borrell C, Lennikov V, de la Fuente GF. Process-generated nanoparticles from ceramic tile sintering: Emissions, exposure and environmental release. Sci Total Environ 2016; 565:922-932. [PMID: 26848012 DOI: 10.1016/j.scitotenv.2016.01.106] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [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: 12/03/2015] [Revised: 01/15/2016] [Accepted: 01/18/2016] [Indexed: 06/05/2023]
Abstract
The ceramic industry is an industrial sector in need of significant process changes, which may benefit from innovative technologies such as laser sintering of ceramic tiles. Such innovations result in a considerable research gap within exposure assessment studies for process-generated ultrafine and nanoparticles. This study addresses this issue aiming to characterise particle formation, release mechanisms and their impact on personal exposure during a tile sintering activity in an industrial-scale pilot plant, as a follow-up of a previous study in a laboratory-scale plant. In addition, possible particle transformations in the exhaust system, the potential for particle release to the outdoor environment, and the effectiveness of the filtration system were also assessed. For this purpose, a tiered measurement strategy was conducted. The main findings evidence that nanoparticle emission patterns were strongly linked to temperature and tile chemical composition, and mainly independent of the laser treatment. Also, new particle formation (from gaseous precursors) events were detected, with nanoparticles <30nm in diameter being formed during the thermal treatment. In addition, ultrafine and nano-sized airborne particles were generated and emitted into workplace air during sintering process on a statistically significant level. These results evidence the risk of occupational exposure to ultrafine and nanoparticles during tile sintering activity since workers would be exposed to concentrations above the nano reference value (NRV; 4×10(4)cm(-3)), with 8-hour time weighted average concentrations in the range of 1.4×10(5)cm(-3) and 5.3×10(5)cm(-3). A potential risk for nanoparticle and ultrafine particle release to the environment was also identified, despite the fact that the efficiency of the filtration system was successfully tested and evidenced a >87% efficiency in particle number concentrations removal.
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Affiliation(s)
- A S Fonseca
- Institute of Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18, 08034 Barcelona, Spain; Universidad de Barcelona, Facultad de Química, Martí i Franquès 1-11, 08028 Barcelona, Spain.
| | - A Maragkidou
- University of Helsinki, Department of Physics, Division of Atmospheric Sciences, P.O. Box 48, (Erik Palmenin aukio 1, Dynamicum), FI-00014, Finland
| | - M Viana
- Institute of Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18, 08034 Barcelona, Spain
| | - X Querol
- Institute of Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18, 08034 Barcelona, Spain
| | - K Hämeri
- University of Helsinki, Department of Physics, Division of Atmospheric Sciences, P.O. Box 48, (Erik Palmenin aukio 1, Dynamicum), FI-00014, Finland
| | - I de Francisco
- Instituto de Ciencia de Materiales de Aragón (ICMA - Universidad de Zaragoza), María de Luna 3, E-50018 Zaragoza, Spain
| | - C Estepa
- Instituto de Ciencia de Materiales de Aragón (ICMA - Universidad de Zaragoza), María de Luna 3, E-50018 Zaragoza, Spain
| | - C Borrell
- Instituto de Ciencia de Materiales de Aragón (ICMA - Universidad de Zaragoza), María de Luna 3, E-50018 Zaragoza, Spain
| | - V Lennikov
- Instituto de Ciencia de Materiales de Aragón (ICMA - Universidad de Zaragoza), María de Luna 3, E-50018 Zaragoza, Spain
| | - G F de la Fuente
- Instituto de Ciencia de Materiales de Aragón (ICMA - Universidad de Zaragoza), María de Luna 3, E-50018 Zaragoza, Spain
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Mølgaard B, Viitanen AK, Kangas A, Huhtiniemi M, Larsen ST, Vanhala E, Hussein T, Boor BE, Hämeri K, Koivisto AJ. Exposure to airborne particles and volatile organic compounds from polyurethane molding, spray painting, lacquering, and gluing in a workshop. Int J Environ Res Public Health 2015; 12:3756-73. [PMID: 25849539 PMCID: PMC4410214 DOI: 10.3390/ijerph120403756] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 03/16/2015] [Accepted: 03/24/2015] [Indexed: 12/07/2022]
Abstract
Due to the health risk related to occupational air pollution exposure, we assessed concentrations and identified sources of particles and volatile organic compounds (VOCs) in a handcraft workshop producing fishing lures. The work processes in the site included polyurethane molding, spray painting, lacquering, and gluing. We measured total VOC (TVOC) concentrations and particle size distributions at three locations representing the various phases of the manufacturing and assembly process. The mean working-hour TVOC concentrations in three locations studied were 41, 37, and 24 ppm according to photo-ionization detector measurements. The mean working-hour particle number concentration varied between locations from 3000 to 36,000 cm−3. Analysis of temporal and spatial variations of TVOC concentrations revealed that there were at least four substantial VOC sources: spray gluing, mold-release agent spraying, continuous evaporation from various lacquer and paint containers, and either spray painting or lacquering (probably both). The mold-release agent spray was indirectly also a major source of ultrafine particles. The workers’ exposure can be reduced by improving the local exhaust ventilation at the known sources and by increasing the ventilation rate in the area with the continuous source.
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Affiliation(s)
- Bjarke Mølgaard
- Department of Physics, University of Helsinki, P.O. Box 48, FI-00014 Helsinki, Finland.
| | - Anna-Kaisa Viitanen
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland.
| | - Anneli Kangas
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland.
| | - Marika Huhtiniemi
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland.
| | - Søren Thor Larsen
- National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark.
| | - Esa Vanhala
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland.
| | - Tareq Hussein
- Department of Physics, University of Helsinki, P.O. Box 48, FI-00014 Helsinki, Finland.
- Department of Physics, Faculty of Science, The University of Jordan, Amman, JO-11942, Jordan.
| | - Brandon E Boor
- Department of Physics, University of Helsinki, P.O. Box 48, FI-00014 Helsinki, Finland.
- Department of Civil, Architectural, and Environmental Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
| | - Kaarle Hämeri
- Department of Physics, University of Helsinki, P.O. Box 48, FI-00014 Helsinki, Finland.
| | - Antti Joonas Koivisto
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland.
- National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark.
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Fonseca AS, Viitanen AK, Koivisto AJ, Kangas A, Huhtiniemi M, Hussein T, Vanhala E, Viana M, Querol X, Hämeri K. Characterization of exposure to carbon nanotubes in an industrial setting. ACTA ACUST UNITED AC 2014; 59:586-99. [PMID: 25539647 DOI: 10.1093/annhyg/meu110] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 10/26/2014] [Indexed: 11/13/2022]
Abstract
While production and use of carbon nanotubes (CNTs) is increasing, workers exposure to CNTs is expected to increase as well, with inhalation being potentially the main pathway for uptake. However, there have been few studies reporting results about workers' personal exposure to CNTs. In this study, worker exposure to single-walled CNTs (SWCNTs) during the production of conductive films in a modern up-scaling factory was assessed. Particulate matter concentrations (2.5-10 μm) and concentrations of CO and CO2 were monitored by using real-time instruments. Workers' exposure levels to SWCNTs were qualitatively estimated by analyzing particle samples by transmission electron microscopy (TEM). TEM samples identified high aspect ratio (length/width > 500) SWCNTs in workplace air. SWCNT concentrations estimated from micrographs varied during normal operation, reactor use without local exhaust ventilation (LEV), and cleaning between 1.7×10(-3), 5.6 and 6.0×10(-3) SWCNT cm(-3), respectively. However, during cleaning it was unclear whether the SWCNTs originated from the cleaning itself or from other reactor openings. We were unable to quantify the SWCNT emissions with online particle instrumentation due to the SWCNT low concentrations compared to background particle concentrations, which were on average 2.6±1.1×10(3)cm(-3). However, CO concentrations were verified as a good indicator of fugitive emissions of SWCNTs. During normal operation, exposure levels were well below proposed limit values (1.0×10(-2) fibers cm(-3) and 1 µg m(-3)) when LEV was used. Based on the results in this study, the analysis of TEM grids seems to be the only direct method to detect SWCNTs in workplace air.
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Affiliation(s)
- Ana Sofia Fonseca
- 1.Institute of Environmental Assessment and Water Research (IDAEA-CSIC), C/ Jordi Girona 18, 08034 Barcelona, Spain 2.Faculty of Chemistry, Department of Analytical Chemistry, University of Barcelona, Martí i Franquès, 1-11, 08028 Barcelona, Spain
| | - Anna-Kaisa Viitanen
- 3.Finnish Institute of Occupational Health, Nanosafety Research Centre, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland
| | - Antti J Koivisto
- 3.Finnish Institute of Occupational Health, Nanosafety Research Centre, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland 4.National Research Centre for the Working Environment, Lersø Parkallé 105, Copenhagen DK-2100, Denmark
| | - Annelli Kangas
- 3.Finnish Institute of Occupational Health, Nanosafety Research Centre, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland
| | - Marika Huhtiniemi
- 3.Finnish Institute of Occupational Health, Nanosafety Research Centre, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland
| | - Tareq Hussein
- 5.Department of Physics, University of Helsinki, PO Box 64, FI-00014 Helsinki, Finland 6.Faculty of Science, Department of Physics, University of Jordan, Amman, JO-11942, Jordan
| | - Esa Vanhala
- 3.Finnish Institute of Occupational Health, Nanosafety Research Centre, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland
| | - Mar Viana
- 1.Institute of Environmental Assessment and Water Research (IDAEA-CSIC), C/ Jordi Girona 18, 08034 Barcelona, Spain
| | - Xavier Querol
- 1.Institute of Environmental Assessment and Water Research (IDAEA-CSIC), C/ Jordi Girona 18, 08034 Barcelona, Spain
| | - Kaarle Hämeri
- 5.Department of Physics, University of Helsinki, PO Box 64, FI-00014 Helsinki, Finland
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Hussein T, Löndahl J, Paasonen P, Koivisto AJ, Petäjä T, Hämeri K, Kulmala M. Modeling regional deposited dose of submicron aerosol particles. Sci Total Environ 2013; 458-460:140-9. [PMID: 23644567 DOI: 10.1016/j.scitotenv.2013.04.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 04/04/2013] [Accepted: 04/08/2013] [Indexed: 05/19/2023]
Abstract
We developed a simple model to calculate the regional deposited dose of submicron aerosol particles in the respiratory system. This model incorporates measured outdoor and modeled indoor particle number size distributions, detailed activity patterns of three age groups (teens, adults, and the elderly), semi-empirical estimation of the regional deposition fraction, hygroscopic properties of urban aerosols, and reported breathing minute volumes. We calculated the total and regional deposited dose based on three concentration metrics: particle number (PN), mass (PM), and surface area (PSA). The 24-h total deposited dose of fine particles in adult males was around 40 μg (57×109 particles, 8×102 mm(2)) and 41 μg (40×109 particles, 8×102 mm(2)) on workdays and weekends, respectively. The total and regional 24-h deposited dose based on any of the metrics was at most 1.5 times higher in males than in females. The deposited dose values in the other age groups were slightly different than in adults. Regardless of the particle size fraction or the deposited dose metric, the pulmonary/alveolar region received the largest fraction of the deposited dose. These values represent the lowest estimate of the deposited dose and they are expected to be higher in real-life conditions after considering indoor sources of aerosol particles and spatial variability of outdoor aerosols. This model can be extended to youngsters (<12 years old) after gaining accurate information about the deposition fraction inside their respiratory system and their breathing pattern. This investigation is foreseen to bridge the gap between exposure and response in epidemiological studies.
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Affiliation(s)
- Tareq Hussein
- University of Helsinki, Department of Physics, P. O. Box 48, FI-00014 UHEL, Helsinki, Finland.
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11
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Karakatsani A, Analitis A, Perifanou D, Ayres JG, Harrison RM, Kotronarou A, Kavouras IG, Pekkanen J, Hämeri K, Kos GPA, de Hartog JJ, Hoek G, Katsouyanni K. Particulate matter air pollution and respiratory symptoms in individuals having either asthma or chronic obstructive pulmonary disease: a European multicentre panel study. Environ Health 2012; 11:75. [PMID: 23039312 PMCID: PMC3509003 DOI: 10.1186/1476-069x-11-75] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 09/24/2012] [Indexed: 05/23/2023]
Abstract
BACKGROUND Particulate matter air pollution has been associated with adverse health effects. The fraction of ambient particles that are mainly responsible for the observed health effects is still a matter of controversy. Better characterization of the health relevant particle fraction will have major implications for air quality policy since it will determine which sources should be controlled.The RUPIOH study, an EU-funded multicentre study, was designed to examine the distribution of various ambient particle metrics in four European cities (Amsterdam, Athens, Birmingham, Helsinki) and assess their health effects in participants with asthma or COPD, based on a detailed exposure assessment. In this paper the association of central site measurements with respiratory symptoms and restriction of activities is examined. METHODS At each centre a panel of participants with either asthma or COPD recorded respiratory symptoms and restriction of activities in a diary for six months. Exposure assessment included simultaneous measurements of coarse, fine and ultrafine particles at a central site. Data on gaseous pollutants were also collected. The associations of the 24-hour average concentrations of air pollution indices with the health outcomes were assessed in a hierarchical modelling approach. A city specific analysis controlling for potential confounders was followed by a meta-analysis to provide overall effect estimates. RESULTS A 10 μg/m3 increase in previous day coarse particles concentrations was positively associated with most symptoms (an increase of 0.6 to 0.7% in average) and limitation in walking (OR= 1.076, 95% CI: 1.026-1.128). Same day, previous day and previous two days ozone concentrations were positively associated with cough (OR= 1.061, 95% CI: 1.013-1.111; OR= 1.049, 95% CI: 1.016-1.083 and OR= 1.059, 95% CI: 1.027-1.091, respectively). No consistent associations were observed between fine particle concentrations, nitrogen dioxide and respiratory health effects. As for particle number concentrations negative association (mostly non-significant at the nominal level) was observed with most symptoms whilst the positive association with limitation of activities did not reach the nominal level of significance. CONCLUSIONS The observed associations with coarse particles are in agreement with the findings of toxicological studies. Together they suggest it is prudent to regulate also coarse particles in addition to fine particles.
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Affiliation(s)
- Anna Karakatsani
- 2nd Department of Respiratory Medicine, “ATTIKON” University Hospital, Medical School, National and Kapodistrian University of Athens, 124 62, Haidari, Greece
| | - Antonis Analitis
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, 115 27, Goudi, Athens, Greece
| | - Dimitra Perifanou
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, 115 27, Goudi, Athens, Greece
| | - Jon G Ayres
- Institute of Occupational and Environmental Medicine, University of Birmingham, Birmingham, United Kingdom
| | - Roy M Harrison
- Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B152TT, United Kingdom
- Department of Environmental Sciences / Center of Excellence in Environmental Studies, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia
| | - Anastasia Kotronarou
- National Observatory of Athens, Institute for Environmental Research and Sustainable Development, Athens, Greece
| | - Ilias G Kavouras
- National Observatory of Athens, Institute for Environmental Research and Sustainable Development, Athens, Greece
| | - Juha Pekkanen
- Department of Environmental Health, National Institute for Health and Welfare, Kuopio, Finland
- Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Kaarle Hämeri
- Department of Physics, University of Helsinki, Helsinki, Finland
| | - Gerard PA Kos
- Energy research Center of the Netherlands, Environment and Energy Engineering, Environmental Assessment, Petten, The Netherlands
| | - Jeroen J de Hartog
- University of Utrecht, Institute for Risk Assessment Sciences, Utrecht, The Netherlands
| | - Gerard Hoek
- University of Utrecht, Institute for Risk Assessment Sciences, Utrecht, The Netherlands
| | - Klea Katsouyanni
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, 115 27, Goudi, Athens, Greece
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Koivisto AJ, Lyyränen J, Auvinen A, Vanhala E, Hämeri K, Tuomi T, Jokiniemi J. Industrial worker exposure to airborne particles during the packing of pigment and nanoscale titanium dioxide. Inhal Toxicol 2012; 24:839-49. [DOI: 10.3109/08958378.2012.724474] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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13
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Manney S, Meddings CM, Harrison RM, Mansur AH, Karakatsani A, Analitis A, Katsouyanni K, Perifanou D, Kavouras IG, Kotronarou N, de Hartog JJ, Pekkanen J, Hämeri K, ten Brink H, Hoek G, Ayres JG. Association between exhaled breath condensate nitrate + nitrite levels with ambient coarse particle exposure in subjects with airways disease. Occup Environ Med 2012; 69:663-9. [PMID: 22767867 DOI: 10.1136/oemed-2011-100255] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Studies of individual inflammatory responses to exposure to air pollution are few but are important in defining the most sensitive markers in better understanding pathophysiological pathways in the lung. The goal of this study was to assess whether exposure to airborne particles is associated with oxidative stress in an epidemiological setting. METHODS The authors assessed exposure to particulate matter air pollution in four European cities in relation to levels of nitrite plus nitrate (NOx) in exhaled breath condensate (EBC) measurements in 133 subjects with asthma or chronic obstructive pulmonary disease using an EBC capture method developed for field use. In each subject, three measurements were collected. Exposure measurements included particles smaller than 10 μm (PM(10)), smaller than 2.5 μm (PM(2.5)) and particle number counts at a central site, outdoors near the subject's home and indoors. RESULTS There were positive and significant relationships between EBC NOx and coarse particles at the central sampling sites (increase of 20.4% (95% CI 6.1% to 36.6%) per 10 μg/m(3) increase of coarse particles of the previous day) but not between EBC NOx and other particle measures. Associations tended to be stronger in subjects not taking steroid medication. CONCLUSIONS An association was found between exposure to ambient coarse particles at central sites and EBC NOx, a marker of oxidative stress. The lack of association between PM measures more indicative of personal exposures (particularly indoor exposure) means interpretation should be cautious. However, EBC NOx may prove to be a marker of PM-induced oxidative stress in epidemiological studies.
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Affiliation(s)
- Sarah Manney
- Department of Respiratory Medicine, Birmingham Heart of England NHS Trust, Birmingham, UK
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14
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Koivisto AJ, Aromaa M, Mäkelä JM, Pasanen P, Hussein T, Hämeri K. Concept to estimate regional inhalation dose of industrially synthesized nanoparticles. ACS Nano 2012; 6:1195-1203. [PMID: 22206417 DOI: 10.1021/nn203857p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The use of nanoparticles (NPs) in industry is increasing rapidly, but knowledge of the occupational health and safety aspects of NPs is still limited. This is because quantitative NP exposure levels are scarce, and the metrics to describe doses are unclear. This study presents one method for estimating workers' calculated regional inhalation dose of deposited particles from size-fractionated concentrations. It was applied to estimate workers' regional inhalation dose rates and doses separately for NPs and NPs with background particles during NP synthesis. Dose analysis was performed in units of particle number (particles and particles min(-1)), active surface area (μm(2) and μm(2) min(-1)), and mass (ng and ng min(-1)) for three respiratory regions: head airways, tracheobronchial, and alveolar. It was found that in NP synthesis NPs were deposited mainly in the alveolar region in all units. However, when the dose of all particles was examined, it was found that dose and the main deposition region were mainly defined by the synthesized NPs for particle number, as active surface area was described by both NPs and background particles, and mass by background particles. This study provides fundamental data for NP inhalation exposure risk assessment, regulations, dose metrics for NP synthesis, and a basis for defining metrics of dose-biological response and helps us understand the magnitude of doses in NP synthesis. It also illustrates the necessity to obtain size-fractionated measurements of NP concentrations to support accurate dose estimation.
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Affiliation(s)
- Antti J Koivisto
- Nanosafety Research Center, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland.
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15
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Hämeri K, Lähde T, Hussein T, Koivisto J, Savolainen K. Facing the key workplace challenge: assessing and preventing exposure to nanoparticles at source. Inhal Toxicol 2010; 21 Suppl 3:17-55. [PMID: 19558229 DOI: 10.3109/08958370903202804] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Nanomaterials present new challenges to understanding, predicting, and managing potential health risks in occupational environments. In this study, we characterize the key physical processes related to formation and growth of nanoparticles. The main focus is on various occupational environments, as these are known to be major environments with nanoparticles in indoor air. The protection of people potentially to be exposed to nanoparticles is one of the key issues in terms of risk assessment and prevention. Two of the main protection techniques that are discussed and characterized are ventilation and filtration, which are widely used in practical applications.
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Affiliation(s)
- K Hämeri
- Finnish Institute of Occupational Health, Helsinki, Finland.
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16
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Rossi EM, Pylkkänen L, Koivisto AJ, Vippola M, Jensen KA, Miettinen M, Sirola K, Nykäsenoja H, Karisola P, Stjernvall T, Vanhala E, Kiilunen M, Pasanen P, Mäkinen M, Hämeri K, Joutsensaari J, Tuomi T, Jokiniemi J, Wolff H, Savolainen K, Matikainen S, Alenius H. Airway exposure to silica-coated TiO2 nanoparticles induces pulmonary neutrophilia in mice. Toxicol Sci 2009; 113:422-33. [PMID: 19875681 DOI: 10.1093/toxsci/kfp254] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The importance of nanotechnologies and engineered nanoparticles has grown rapidly. It is therefore crucial to acquire up-to-date knowledge of the possible harmful health effects of these materials. Since a multitude of different types of nanosized titanium dioxide (TiO(2)) particles are used in industry, we explored their inflammatory potential using mouse and cell models. BALB/c mice were exposed by inhalation for 2 h, 2 h on 4 consecutive days, or 2 h on 4 consecutive days for 4 weeks to several commercial TiO(2) nanoparticles, SiO(2) nanoparticles, and to nanosized TiO(2) generated in a gas-to-particle conversion process at 10 mg/m(3). In addition, effects of in vitro exposure of human macrophages and fibroblasts (MRC-9) to the different particles were assessed. SiO(2)-coated rutile TiO(2) nanoparticles (cnTiO(2)) was the only sample tested that elicited clear-cut pulmonary neutrophilia. Uncoated rutile and anatase as well as nanosized SiO(2) did not induce significant inflammation. Pulmonary neutrophilia was accompanied by increased expression of tumor necrosis factor-alpha (TNF-alpha) and neutrophil-attracting chemokine CXCL1 in the lung tissue. TiO(2) particles accumulated almost exclusively in the alveolar macrophages. In vitro exposure of murine and human macrophages to cnTiO(2) elicited significant induction of TNF-alpha and neutrophil-attracting chemokines. Stimulation of human fibroblasts with cnTiO(2)-activated macrophage supernatant induced high expression of neutrophil-attracting chemokines, CXCL1 and CXCL8. Interestingly, the level of lung inflammation could not be explained by the surface area of the particles, their primary or agglomerate particle size, or radical formation capacity but is rather explained by the surface coating. Our findings emphasize that it is vitally important to take into account in the risk assessment that alterations of nanoparticles, e.g., by surface coating, may drastically change their toxicological potential.
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Affiliation(s)
- Elina M Rossi
- Unit of Excellence for Immunotoxicology, Finnish Institute of Occupational Health, Helsinki, Finland
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Hämeri K, Lähde T, Hussein T, Koivisto J, Savolainen K. Facing the key workplace challenge: Assessing and preventing exposure to nanoparticles at source. Inhal Toxicol 2009. [DOI: 10.1080/08958370902942525] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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18
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Asmi E, Antola M, Yli-Tuomi T, Jantunen M, Aarnio P, Mäkelä T, Hillamo R, Hämeri K. Driver and passenger exposure to aerosol particles in buses and trams in Helsinki, Finland. Sci Total Environ 2009; 407:2860-2867. [PMID: 19195679 DOI: 10.1016/j.scitotenv.2009.01.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2008] [Revised: 12/18/2008] [Accepted: 01/05/2009] [Indexed: 05/27/2023]
Abstract
This study investigates commuter and driver exposure to aerosol particles in buses and trams in Helsinki, Finland. Particle number and PM(2.5) concentrations were determined in the cabin and the driver's compartment. In addition, the <2.5 microm black carbon concentration was measured in the driver's compartment and PM(2.5) was collected for elemental analysis in the cabin. The measurements were repeated on two generations of buses and trams including two measurement days in each vehicle type. Fine particle number and mass concentrations in the driver's compartments were only slightly increased compared to Helsinki background air. Daily average ratios of number and mass to the background varied in range 0.8-4.3 and 1.0-2.9, respectively, both being the highest in the older bus type. However, the drivers were exposed to elevated levels of black carbon, which some studies have addressed to be strongly correlated with adverse health effects. The daily average ratio of black carbon to the background varied between 2.4 and 11.4. Additionally, the black carbon concentration had spatial variation. The drivers were exposed to higher peak concentrations of black carbon in downtown area. Particle concentrations were smaller in the driver's compartment than in the cabin. The newer technology in the newer model of the tram and bus seemed to decrease driver exposure to aerosol particles.
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Affiliation(s)
- Eija Asmi
- Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, FI-00250 Helsinki, Finland.
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19
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Welling I, Lehtimäki M, Rautio S, Lähde T, Enbom S, Hynynen P, Hämeri K. Wood dust particle and mass concentrations and filtration efficiency in sanding of wood materials. J Occup Environ Hyg 2009; 6:90-98. [PMID: 19065389 DOI: 10.1080/15459620802623073] [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] [Indexed: 05/27/2023]
Abstract
The importance of fine particles has become apparent as the knowledge of their effects on health has increased. Fine particle concentrations have been published for outside air, plasma arc cutting, welding, and grinding, but little data exists for the woodworking industry. Sanding was evaluated as the producer of the woodworking industry's finest particles, and was selected as the target study. The number of dust particles in different particle size classes and the mass concentrations were measured in the following environments: workplace air during sanding in plywood production and in the inlet and return air; in the dust emission chamber; and in filter testing. The numbers of fine particles were low, less than 10(4) particles/cm(3) (10(7) particles/L). They were much lower than typical number concentrations near 10(6) particles/cm(3) measured in plasma arc cutting, grinding, and welding. Ultrafine particles in the size class less than 100 nm were found during sanding of MDF (medium density fiberboard) sheets. When the cleaned air is returned to the working areas, the dust content in extraction systems must be monitored continuously. One way to monitor the dust content in the return air is to use an after-filter and measure pressure drop across the filter to indicate leaks in the air-cleaning system. The best after-filtration materials provided a clear increase in pressure drop across the filter in the loading of the filter. The best after-filtration materials proved to be quite effective also for fine particles. The best mass removal efficiencies for fine particles around 0.3 mum were over 80% for some filter materials loaded with sanding wood dust.
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Affiliation(s)
- Irma Welling
- Finnish Institute of Occupational Health, Lappeenranta, Lappeenranat, Finland.
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20
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Lähde T, Rönkkö T, Virtanen A, Schuck TJ, Pirjola L, Hämeri K, Kulmala M, Arnold F, Rothe D, Keskinen J. Heavy duty diesel engine exhaust aerosol particle and ion measurements. Environ Sci Technol 2009; 43:163-168. [PMID: 19209601 DOI: 10.1021/es801690h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Heavy duty EURO 4 diesel engine exhaust particle and ion size distributions were measured atthetailpipe using dynamometer testing. Measurements of particle volatility and electrical charge were undertaken to clarify diesel exhaust nucleation mode characteristics with different exhaust after-treatment systems. Nucleation mode particle volatility and charging probability were dependent on exhaust after-treatment particles were volatile and uncharged when the engine was equipped with diesel particulate filter and partly volatile and partly charged in exhaust without any after-treatment or with an oxidation catalyst only. The absence of charged particles in the nucleation mode of diesel particulate filtered exhaust excludes the ion mediated process as a nucleation particle formation mechanism.
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Affiliation(s)
- Tero Lähde
- Aerosol Physics Laboratory, Department of Physics, Tampere University of Technology, P. O. Box 692, FIN -33101, Tampere, Finland
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Virkkula A, Mäkelä T, Hillamo R, Yli-Tuomi T, Hirsikko A, Hämeri K, Koponen IK. A simple procedure for correcting loading effects of aethalometer data. J Air Waste Manag Assoc 2007; 57:1214-22. [PMID: 17972766 DOI: 10.3155/1047-3289.57.10.1214] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A simple method for correcting for the loading effects of aethalometer data is presented. The formula BC(CORRECTED) = (1 + k x ATN) x BC(NONCORRECTED), where ATN is the attenuation and BC is black carbon, was used for correcting aethalometer data obtained from measurements at three different sites: a subway station in Helsinki, an urban background measurement station in Helsinki, and a rural station in Hyytiälä in central Finland. The BC data were compared with simultaneously measured aerosol volume concentrations (V). After the correction algorithm, the BC-to-V ratio remained relatively stable between consequent filter spots, which can be regarded as indirect evidence that the correction algorithm works. The k value calculated from the outdoor sites had a clear seasonal cycle that could be explained by darker aerosol in winter than in summer. When the contribution of BC to the total aerosol volume was high, the k factor was high and vice versa. In winter, the k values at all wavelengths were very close to that obtained from the subway station data. In summer, the k value was wavelength dependent and often negative. When the k value is negative, the noncorrected BC concentrations overestimated the true concentrations.
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Affiliation(s)
- Aki Virkkula
- Department of Air Quality Research, Finnish Meteorological Institute, Research and Development, Helsinki, Finland.
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Aalto P, Hämeri K, Paatero P, Kulmala M, Bellander T, Berglind N, Bouso L, Castaño-Vinyals G, Sunyer J, Cattani G, Marconi A, Cyrys J, von Klot S, Peters A, Zetzsche K, Lanki T, Pekkanen J, Nyberg F, Sjövall B, Forastiere F. Aerosol particle number concentration measurements in five European cities using TSI-3022 condensation particle counter over a three-year period during health effects of air pollution on susceptible subpopulations. J Air Waste Manag Assoc 2005; 55:1064-76. [PMID: 16187577 DOI: 10.1080/10473289.2005.10464702] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In this study, long-term aerosol particle total number concentration measurements in five metropolitan areas across Europe are presented. The measurements have been carried out in Augsburg, Barcelona, Helsinki, Rome, and Stockholm using the same instrument, a condensation particle counter (TSI model 3022). The results show that in all of the studied cities, the winter concentrations are higher than the summer concentrations. In Helsinki and in Stockholm, winter concentrations are higher by a factor of two and in Augsburg almost by a factor of three compared with summer months. The winter maximum of the monthly average concentrations in these cities is between 10,000 cm(-3) and 20,000 cm(-3), whereas the summer min is approximately 5000-6000 cm(-3). In Rome and in Barcelona, the winters are more polluted compared with summers by as much as a factor of 4-10. The winter maximum in both Rome and Barcelona is close to 100,000 cm(-3), whereas the summer minimum is > 10,000 cm(-3). During the weekdays the maximum of the hourly average concentrations in all of the cities is detected during the morning hours between 7 and 10 a.m. The evening maxima were present in Barcelona, Rome, and Augsburg, but these were not as pronounced as the morning ones. The daily maxima in Helsinki and Stockholm are close or even lower than the daily minima in the more polluted cities. The concentrations between these two groups of cities are different with a factor of about five during the whole day. The study pointed out the influence of the selection of the measurement site and the configuration of the sampling line on the observed concentrations.
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Affiliation(s)
- Pasi Aalto
- Department of Physical Sciences, University of Helsinki, Helsinki, Finland
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Mönkkönen P, Pai P, Maynard A, Lehtinen KEJ, Hämeri K, Rechkemmer P, Ramachandran G, Prasad B, Kulmala M. Fine particle number and mass concentration measurements in urban Indian households. Sci Total Environ 2005; 347:131-47. [PMID: 16084974 DOI: 10.1016/j.scitotenv.2004.12.023] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2004] [Accepted: 12/17/2004] [Indexed: 05/03/2023]
Abstract
Fine particle number concentration (D(p)>10 nm, cm(-3)), mass concentrations (approximation of PM(2.5), microg m(-3)) and indoor/outdoor number concentration ratio (I/O) measurements have been conducted for the first time in 11 urban households in India, 2002. The results indicate remarkable high indoor number and mass concentrations and I/O number concentration ratios caused by cooking. Besides cooking stoves that used liquefied petroleum gas (LPG) or kerosene as the main fuel, high indoor concentrations can be explained by poor ventilation systems. Particle number concentrations of more than 300,000 cm(-3) and mass concentrations of more than 1000 microg m(-3) were detected in some cases. When the number and mass concentrations during cooking times were statistically compared, a correlation coefficient r>0.50 was observed in 63% of the households. Some households used other fuels like wood and dung cakes along with the main fuel, but also other living activities influenced the concentrations. In some areas, outdoor combustion processes had a negative impact on indoor air quality. The maximum concentrations observed in most cases were due to indoor combustion sources. Reduction of exposure risk and health effects caused by poor indoor air in urban Indian households is possible by improving indoor ventilation and reducing penetration of outdoor particles.
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Affiliation(s)
- P Mönkkönen
- University of Helsinki, Department of Physical Sciences, P.O. Box 64, 00014 Helsinki, Finland.
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O'Dowd CD, Jimenez JL, Bahreini R, Flagan RC, Seinfeld JH, Hämeri K, Pirjola L, Kulmala M, Jennings SG, Hoffmann T. Marine aerosols and iodine emissions (Reply). Nature 2005. [DOI: 10.1038/nature03373] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Timonen KL, Hoek G, Heinrich J, Bernard A, Brunekreef B, de Hartog J, Hämeri K, Ibald-Mulli A, Mirme A, Peters A, Tiittanen P, Kreyling WG, Pekkanen J. Daily variation in fine and ultrafine particulate air pollution and urinary concentrations of lung Clara cell protein CC16. Occup Environ Med 2004; 61:908-14. [PMID: 15477284 PMCID: PMC1757829 DOI: 10.1136/oem.2004.012849] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Daily variations in ambient particulate air pollution have been associated with respiratory mortality and morbidity. AIMS To assess the associations between urinary concentration of lung Clara cell protein CC16, a marker for lung damage, and daily variation in fine and ultrafine particulate air pollution. METHODS Spot urinary samples (n = 1249) were collected biweekly for six months in subjects with coronary heart disease in Amsterdam, Netherlands (n = 37), Erfurt, Germany (n = 47), and Helsinki, Finland (n = 47). Ambient particulate air pollution was monitored at a central site in each city. RESULTS The mean 24 hour number concentration of ultrafine particles was 17.3x10(3) cm(-3) in Amsterdam, 21.1x10(3) cm(-3) in Erfurt, and 17.0x10(3) cm(-3) in Helsinki. The mean 24 hour PM2.5 concentrations were 20, 23, and 13 microg/m3, respectively. Daily variation in ultrafine particle levels was not associated with CC16. In contrast, CC16 concentration seemed to increase with increasing levels of PM2.5 in Helsinki, especially among subjects with lung disorders. No clear associations were observed in Amsterdam and Erfurt. In Helsinki, the CC16 concentration increased by 20.2% (95% CI 6.9 to 33.5) per 10 microg/m3 increase in PM2.5 concentration (lag 2). The respective pooled effect estimate was 2.1% (95% CI -1.3 to 5.6). CONCLUSION The results suggest that exposure to particulate air pollution may lead to increased epithelial barrier permeability in lungs.
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Affiliation(s)
- K L Timonen
- Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital and University of Kuopio, PO Box 1777, FIN-70211 Kuopio, Finland.
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Hussein T, Hämeri K, Aalto P, Asmi A, Kakko L, Kulmala M. Particle size characterization and the indoor-to-outdoor relationship of atmospheric aerosols in Helsinki. Scand J Work Environ Health 2004; 30 Suppl 2:54-62. [PMID: 15487686] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
OBJECTIVES The influence of traffic and meteorological conditions on aerosol characteristics outdoors, the relationship between indoor and outdoor aerosol particles, and the pollutant transport indoors by means of a mechanical ventilation system were studied. METHODS Indoor and outdoor concentrations of fine-particle numbers were measured during the summer (15 May--30 June 2000) in one office located in the basement of a building in Helsinki, Finland. The total number concentration was measured with a condensation particle counter, and the particle number size distribution (7-600 nm) was measured with a differential mobility particle sizer. The size distribution (0.3-25 microm) of the indoor particle numbers was periodically measured with a laser particle counter. RESULTS Meteorological conditions, especially wind direction, had the greatest effect on the total number concentration and the size distribution of aerosol particles outdoors. The outdoor number concentration of ultrafine particles (diameter <100 nm) was strongly dependent on traffic density. The temporal variations in the indoor number concentration of ultrafine and fine particles (7-600 nm) closely followed the corresponding temporal variations outdoors. The building ventilation system was the main means of transporting aerosols indoors. The mean penetration factor was 0.41 (SD 0.11) for the nucleation mode (7-25 nm), 0.74 (SD 0.09) for the Aitken mode (25-100 nm), and 0.87 (SD 0.06) for the accumulation mode (100-600 nm). CONCLUSIONS The ultrafine particles were bimodal with a nucleation mode (particle diameter <25 nm) and an Aitken mode (25 nm <particle diameter <100 nm). An accumulation mode was observed with a particle diameter larger than 100 nm. The patterns of fine-particulate air pollution inside an office can be largely estimated on the basis of the outdoor aerosol characterization and the mechanical ventilation system.
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Affiliation(s)
- Tareq Hussein
- University of Helsinki, Department of Physical Sciences, Helsinki, Finland
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Hämeri K, Gaman A, Hussein T, Räisänen J, Niemelä R, Aalto PP, Kulmala M. Particle concentration profile in a vertical displacement flow: a study in an industrial hall. Appl Occup Environ Hyg 2003; 18:183-92. [PMID: 12573964 DOI: 10.1080/10473220301351] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The effect of displacement flow on the distribution of aerosol concentration was investigated in an industrial hall. According to the displacement ventilation principle, vertical upflow is accomplished by introducing fresh air, cooler than room air, into the occupied zone near floor level. The fresh air is introduced from low-velocity devices and heated by warm processes. This technique allows warm air contaminants to rise to the ceiling, and the rising plume is then exhausted close to the ceiling. This study presents the results of a field study conducted in an industrial environment. The aerosol properties and behavior, especially the vertical gradients, are characterized in a displacement flow field. The results indicate that the fine particles, less than 1 microm in diameter, are transported away from the breathing zone by the ventilation process. However, the air quality is significantly influenced by the emission source, and therefore the number concentration of fine and ultrafine (smaller than 0.1 microm in diameter) aerosol particles in the breathing zone was clearly elevated compared to that of the incoming clean air. The vertical gradients displayed clear size dependence; the strongest gradients were found for particles between 0.003 and 0.015 microm in diameter.
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Affiliation(s)
- Kaarle Hämeri
- Finnish Institute of Occupational Health, Helsinki, Finland
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O'Dowd CD, Jimenez JL, Bahreini R, Flagan RC, Seinfeld JH, Hämeri K, Pirjola L, Kulmala M, Jennings SG, Hoffmann T. Marine aerosol formation from biogenic iodine emissions. Nature 2002; 417:632-6. [PMID: 12050661 DOI: 10.1038/nature00775] [Citation(s) in RCA: 281] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The formation of marine aerosols and cloud condensation nuclei--from which marine clouds originate--depends ultimately on the availability of new, nanometre-scale particles in the marine boundary layer. Because marine aerosols and clouds scatter incoming radiation and contribute a cooling effect to the Earth's radiation budget, new particle production is important in climate regulation. It has been suggested that sulphuric acid derived from the oxidation of dimethyl sulphide is responsible for the production of marine aerosols and cloud condensation nuclei. It was accordingly proposed that algae producing dimethyl sulphide play a role in climate regulation, but this has been difficult to prove and, consequently, the processes controlling marine particle formation remains largely undetermined. Here, using smog chamber experiments under coastal atmospheric conditions, we demonstrate that new particles can form from condensable iodine-containing vapours, which are the photolysis products of biogenic iodocarbons emitted from marine algae. Moreover, we illustrate, using aerosol formation models, that concentrations of condensable iodine-containing vapours over the open ocean are sufficient to influence marine particle formation. We suggest therefore that marine iodocarbon emissions have a potentially significant effect on global radiative forcing.
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Affiliation(s)
- Colin D O'Dowd
- Department of Physics, National University of Ireland, Galway,
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Hämeri K. Evaluating measurements of new particle concentrations, source rates, and spatial scales during coastal nucleation events using condensation particle counters. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001jd000411] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Zhou J, Swietlicki E, Berg OH, Aalto PP, Hämeri K, Nilsson ED, Leck C. Hygroscopic properties of aerosol particles over the central Arctic Ocean during summer. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000jd900426] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Romakkaniemi S, Hämeri K, Väkevä M, Laaksonen A. Adsorption of Water on 8−15 nm NaCl and (NH4)2SO4 Aerosols Measured Using an Ultrafine Tandem Differential Mobility Analyzer. J Phys Chem A 2001. [DOI: 10.1021/jp010647l] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Sami Romakkaniemi
- Department of Applied Physics, University of Kuopio, P.O. Box 1627, 70211 Kuopio, Finland, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, 00250 Helsinki, Finland, and Department of Physics, P.O. Box 9, 00014 University of Helsinki, Finland
| | - Kaarle Hämeri
- Department of Applied Physics, University of Kuopio, P.O. Box 1627, 70211 Kuopio, Finland, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, 00250 Helsinki, Finland, and Department of Physics, P.O. Box 9, 00014 University of Helsinki, Finland
| | - Minna Väkevä
- Department of Applied Physics, University of Kuopio, P.O. Box 1627, 70211 Kuopio, Finland, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, 00250 Helsinki, Finland, and Department of Physics, P.O. Box 9, 00014 University of Helsinki, Finland
| | - Ari Laaksonen
- Department of Applied Physics, University of Kuopio, P.O. Box 1627, 70211 Kuopio, Finland, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, 00250 Helsinki, Finland, and Department of Physics, P.O. Box 9, 00014 University of Helsinki, Finland
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Djikaev YS, Bowles R, Reiss H, Hämeri K, Laaksonen A, Väkevä M. Theory of Size Dependent Deliquescence of Nanoparticles: Relation to Heterogeneous Nucleation and Comparison with Experiments. J Phys Chem B 2001. [DOI: 10.1021/jp010537e] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Y. S. Djikaev
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095
| | - R. Bowles
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095
| | - H. Reiss
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095
| | - K. Hämeri
- Finnish Institute of Occupational Health, Laajaniityntie 1, FIN-01620 Vantaa, Finland
| | - A. Laaksonen
- Department of Applied Physics, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland
| | - M. Väkevä
- Department of Physics, University of Helsinki, P.O. Box 9, FIN-00014 Helsinki, Finland
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Hämeri K, Väkevä M, Hansson HC, Laaksonen A. Hygroscopic growth of ultrafine ammonium sulphate aerosol measured using an ultrafine tandem differential mobility analyzer. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000jd900220] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Väkevä M, Hämeri K, Puhakka T, Nilsson ED, Hohti H, Mäkelä JM. Effects of meteorological processes on aerosol particle size distribution in an urban background area. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999jd901143] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hämeri K, Kulmala M. Homogeneous nucleation in a laminar flow diffusion chamber: The effect of temperature and carrier gas on dibutyl phthalate vapor nucleation rate at high supersaturations. J Chem Phys 1996. [DOI: 10.1063/1.472552] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Hämeri K, Kulmala M, Krissinel’ E, Kodenyov G. Homogeneous nucleation in a laminar flow diffusion chamber: The operation principles and possibilities for quantitative rate measurements. J Chem Phys 1996. [DOI: 10.1063/1.472551] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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