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Intro -- The Handbook of Environmental Chemistry Also Available Electronically -- Aims and Scope -- Series Preface -- Volume Preface -- References -- Contents -- Dosimetry and Toxicology of Nanosized Particles and Fibres -- 1 Introduction -- 2 Factors That Affect Deposition and Clearance -- 3 Deposition Patterns of Spherical Nanoparticles in the Human Respiratory Tract -- 4 Deposition Patterns of Fibres in the Human Respiratory Tract -- 5 Particle Retention and Relocation Pathways Within the Lungs -- 6 Extrapolation from Single Dose to Chronic Exposure -- 7 Toxicity -- References -- Measurement Methods for Nanoparticles in Indoor and Outdoor Air -- 1 Introduction -- 2 Measurement Methods -- 2.1 Stationary Equipment -- 2.1.1 Time-Resolving Instruments -- Measurement of Particle Number Concentration -- Measurement of Particle Lung-Deposited Surface Area Concentration -- Measurement of Particle Mass Concentration -- Measurement of Particle Size Distribution by Electrical Mobility Analysis -- Measurement of Particle Size Distribution by Inertial Separation -- 2.1.2 Time-Integrating Instruments -- Filter Sampling -- Electrostatic Sampling -- 2.2 Portable Equipment -- 2.2.1 Time-Resolving Instruments -- Measurement of Particle Number Concentration -- Measurement of Lung-Deposited Surface Area Concentration -- Measurement of Particle Size Distribution -- 2.2.2 Time-Integrating Instruments -- 2.3 Personal Equipment -- 2.3.1 Time-Resolving Instruments -- Measurement of Number Concentration, Lung-Deposited Surface Area Concentration, and Mean Particle Size -- Measurement of Lung-Deposited Surface Area Concentration -- 2.3.2 Time-Integrating Instruments -- Thermophoretic Sampling -- Sampling on Different Filtration Media -- References -- Exposure Assessment: Methods -- 1 Introduction -- 2 The Aim of Exposure Assessment.

In eleven chapters authored by expert air quality scientists and specialists from academia and city administrations, this book describes the problem of urban PM air pollution and combines the experiences of different European cities concerning the selection, implementation and evaluation of the effectiveness of specific measures to improve air quality

36 p. ; The mass concentration, chemical composition and sources of quasi-ultrafine (quasi-UFP, PM0.25), accumulation (PM0.25–2.5) and coarse mode (PM2.5–10) particles were determined in indoor and outdoor air at 39 schools in Barcelona (Spain). Quasi-UFP mass concentrations measured (25.6 μg m−3 outdoors, 23.4 μg m−3 indoors) are significantly higher than those reported in other studies, and characterised by higher carbonaceous and mineral matter contents and a lower proportion of secondary inorganic ions. Results suggest that quasi-UFPs in Barcelona are affected by local sources in the schools, mainly human activity (e.g. organic material from textiles, etc., contributing 23–46% to total quasi-UFP mass) and playgrounds (in the form of mineral matter, contributing about 9% to the quasi-UFP mass). The particle size distribution patterns of toxicologically relevant metals and major aerosol components was characterised, displaying two modes for most elements and components, and one mode for inorganic salts (ammonium nitrate and sulfate) and elemental carbon (EC). Regarding metals, Ni and Cr were partitioned mainly in quasi-UFPs and could thus be of interest for epidemiological studies, given their high redox properties. Exposure of children to quasi-UFP mass and chemical species was assessed by comparing the concentrations measured at urban background and traffic areas schools. Finally, three main indoor sources across all size fractions were identified by assessing indoor / outdoor ratios (I / O) of PM species used as their tracers: human activity (organic material), cleaning products, paints and plastics (Cl− source), and a metallic mixed source (comprising combinations of Cu, Zn, Co, Cd, Pb, As, V and Cr). Our results support the need to enforce targeted legislation to determine a minimum "safe" distance between major roads and newly built schools to reduce exposure to traffic-derived metals in quasi-UFPs. ; Peer reviewed

Abstract
Assessing exposure to nanomaterials in industrial workplaces is a widespread challenge. Nanoparticle release was evaluated, under real-world operating conditions, in one thermal spraying and one tile firing facility. Nanoparticles were characterised in terms of mass and number concentrations (µg/m3; /cm3), particle size distribution, chemical composition and morphology, and in vitro toxicity. The present work targets especially the toxicological characterisation of the aerosols sampled. Particles <2 microns in size were sampled in cell-culture medium using an SKC Biosampler connected to a pump operating at 12 lpm. Samples were conserved frozen at -20ºC until analysis. Submerged-cell cultures using the commercially-available A549 cell line were used for the in-vitro assays, where cell viability and generation of reactive-oxygen species (ROS) were assessed. Preliminary results evidenced a relatively large variability across samples in terms of cell viability, with reductions ranging between <5% and up to 60% after 2-hour exposures. Results suggested that the initial INP concentration in the samples may play a relevant role in the results, as in highly concentrated samples nanoparticles may interfere with the cellular uptake of the Alamar Blue dye used and, subsequently, on fluorescence results. ROS generation was detected increasingly over time during the test period (1-4 hours). Readings obtained after 3-4 hour became mostly stable. Finally, these results provide the baseline for the subsequent assessment of the expected reduction in INP concentrations and toxicity resulting from the implementation of risk mitigation measures, which will focus on a custom-designed air filtration system developed in the framework of this project.

The mass concentration, chemical composition and sources of quasi-ultrafine (quasi-UFP, PM0.25), accumulation (PM0.25–2.5) and coarse mode (PM2.5–10) particles were determined in indoor and outdoor air at 39 schools in Barcelona (Spain). Quasi-UFP mass concentrations measured (25.6 μg m−3 outdoors, 23.4 μg m−3 indoors) are significantly higher than those reported in other studies, and characterised by higher carbonaceous and mineral matter contents and a lower proportion of secondary inorganic ions. Results suggest that quasi-UFPs in Barcelona are affected by local sources in the schools, mainly human activity (e.g. organic material from textiles, etc., contributing 23–46% to total quasi-UFP mass) and playgrounds (in the form of mineral matter, contributing about 9% to the quasi-UFP mass). The particle size distribution patterns of toxicologically relevant metals and major aerosol components was characterised, displaying two modes for most elements and components, and one mode for inorganic salts (ammonium nitrate and sulfate) and elemental carbon (EC). Regarding metals, Ni and Cr were partitioned mainly in quasi-UFPs and could thus be of interest for epidemiological studies, given their high redox properties. Exposure of children to quasi-UFP mass and chemical species was assessed by comparing the concentrations measured at urban background and traffic areas schools. Finally, three main indoor sources across all size fractions were identified by assessing indoor / outdoor ratios (I / O) of PM species used as their tracers: human activity (organic material), cleaning products, paints and plastics (Cl− source), and a metallic mixed source (comprising combinations of Cu, Zn, Co, Cd, Pb, As, V and Cr). Our results support the need to enforce targeted legislation to determine a minimum "safe" distance between major roads and newly built schools to reduce exposure to traffic-derived metals in quasi-UFPs. ; No

One- and two-box models have been pointed out as useful tools for modelling indoor particle exposure. However, model performance still needs further testing if they are to be implemented as trustworthy tools for exposure assessment. The objective of this work is to evaluate the performance, applicability and reproducibility of one- and two-box models on real-world industrial scenarios. A study on filling of seven materials in three filling lines with different levels of energy and mitigation strategies was used. Inhalable and respirable mass concentrations were calculated with one- and two-box models. The continuous drop and rotating drum methods were used for emission rate calculation, and ranges from a one-at-a-time methodology were applied for local exhaust ventilation efficiency and inter-zonal air flows. When using both dustiness methods, large differences were observed for modelled inhalable concentrations but not for respirable, which showed the importance to study the linkage between dustiness and processes. Higher model accuracy (ratio modelled vs. measured concentrations 0.5–5) was obtained for the two- (87%) than the one-box model (53%). Large effects on modelled concentrations were seen when local exhausts ventilation and inter-zonal variations where parametrized in the models. However, a certain degree of variation (10–20%) seems acceptable, as similar conclusions are reached. ; This research was funded by the Spanish MINECO (CGL2015-66777-C2–1-R, 2-R and 679 RTI2018-098095-B-C21) and Danish Government (FFIKA, Focused Research Effort on Chemicals in 680 the Working Environment). Additional support was provided by the Spanish Ministry of Science and Innovation (Project CEX2018-000794-S), Generalitat de Catalunya AGAUR 2017 SGR41, and 682 FEDER (European Regional Development Fund) "Una manera de hacer Europa". ; Peer reviewed

Thermal-optical analysis is currently under consideration by the European standardization body (CEN) as the reference method to quantitatively determine organic carbon (OC) and elemental carbon (EC) in ambient air. This paper presents an overview of the critical parameters related to the thermal-optical analysis including thermal protocols, critical factors and interferences of the methods examined, method inter-comparisons, inter-laboratory exercises, biases and artifacts, and reference materials. The most commonly used thermal protocols include NIOSH-like, IMPROVE_A and EUSAAR_2 protocols either with light transmittance or reflectance correction for charring. All thermal evolution protocols are comparable for total carbon (TC) concentrations but the results vary significantly concerning OC and especially EC concentrations. Thermal protocols with a rather low peak temperature in the inert mode like IMPROVE_A and EUSAAR_2 tend to classify more carbon as EC compared to NIOSH-like protocols, while charring correction based on transmittance usually leads to smaller EC values compared to reflectance. The difference between reflectance and transmittance correction tends to be larger than the difference between different thermal protocols. Nevertheless, thermal protocols seem to correlate better when reflectance is used as charring correction method. The difference between EC values as determined by the different protocols is not only dependent on the optical pyrolysis correction method, but also on the chemical properties of the samples due to different contributions from various sources. The overall conclusion from this literature review is that it is not possible to identify the "best" thermal-optical protocol based on literature data only, although differences attributed to the methods have been quantified when possible. ; This work was undertaken under Mandate M/503 "Standardisation mandate to CEN, CENELEC and ETSI in support of the implementation of the Ambient Air Quality Legislation", ENX "Ambient air – Measurement of airborne lemental carbon (EC) and organic carbon (OC) in PM 2.5 deposited on filters". ; EUR 1,920 APC fee funded by the EC FP7 Post-Grant Open Access Pilot ; Peer reviewed

Studies on ultrafine particles (diameter < 100nm) and air quality have mostly focused on vehicle exhaust emissions and on new particle formation in "clean" ambient air. Here we present a study focused on the processes contributing to ultrafine particle concentrations in a city (Huelva, SW Spain) placed close to a coastal area where significant anthropogenic emissions of aerosol precursors occur. The overall data analysis shows that two processes predominantly contribute to the number of particles coarser than 2.5 nm: vehicle exhaust emissions and new particle formation due to photo-chemical activity. As typically occurs in urban areas, vehicle exhaust emissions result in high concentrations of black carbon (BC) and particles coarser than 2.5 nm (N) during the morning rush hours. The highest N concentrations were recorded during the 11:00–17:00 h period, under the sea breeze regime, when low BC concentrations were registered and photochemical activity resulted in high O3 levels and in new particle formation in the aerosol precursors' rich inland airflow. In this period, it is estimated that about 80% of the number of particles are linked to sulfur dioxide emissions. The contributions to N of "carbonaceous material and those compounds nucleating/condensing immediately after emission" and of the "new particle formation processes in air masses rich gaseous precursors (e.g. SO2)" were estimated by means of a relatively novel method based on simultaneous measurements of BC and N. A comparison with two recent studies suggests that the daily cycles of "new particle formation" during the inland sea breeze is blowing period seem to be a feature of ultrafine particles in coastal areas of South-west Europe. ; This study has been carried out within the framework of several research projects: AER-REG (P07-RNM- 03125; Department of Innovation, Science and Enterprise of the Andalusian Autonomous Government), GRACCIE (CSD2007- 00067; Ministry of Science and Innovation of Spain), SIMAND (P07- RNM-02729; Department of ...

Studies on ultrafine particles (diameter < 100nm) and air quality have mostly focused on vehicle exhaust emissions and on new particle formation in "clean" ambient air. Here we present a study focused on the processes contributing to ultrafine particle concentrations in a city (Huelva, SW Spain) placed close to a coastal area where significant anthropogenic emissions of aerosol precursors occur. The overall data analysis shows that two processes predominantly contribute to the number of particles coarser than 2.5 nm: vehicle exhaust emissions and new particle formation due to photo-chemical activity. As typically occurs in urban areas, vehicle exhaust emissions result in high concentrations of black carbon (BC) and particles coarser than 2.5 nm (N) during the morning rush hours. The highest N concentrations were recorded during the 11:00–17:00 h period, under the sea breeze regime, when low BC concentrations were registered and photochemical activity resulted in high O3 levels and in new particle formation in the aerosol precursors' rich inland airflow. In this period, it is estimated that about 80% of the number of particles are linked to sulfur dioxide emissions. The contributions to N of "carbonaceous material and those compounds nucleating/condensing immediately after emission" and of the "new particle formation processes in air masses rich gaseous precursors (e.g. SO2)" were estimated by means of a relatively novel method based on simultaneous measurements of BC and N. A comparison with two recent studies suggests that the daily cycles of "new particle formation" during the inland sea breeze is blowing period seem to be a feature of ultrafine particles in coastal areas of South-west Europe. ; This study has been carried out within the framework of several research projects: AER-REG (P07-RNM-03125; Regional Ministry of Innovation, Science and Enterprise of the Andalusian Autonomous Government), GRACCIE (CSD2007-00067; Ministry of Science and Innovation of Spain), SIMAND (P07-RNM-02729; Regional Ministry ...