bluuebunny/crossref_metadata_2025_split huggingface dataset:
101 PAH Exposure During Construction of Railroad Swithes with Creosote Impregnated Ties
Authors: Graff Pål , Westberg Håkan , Strandberg Bo , Lindh Christian , Bryngelsson Ing-Liss , Hagberg Jessika 
Published: May 2023

Abstract
Coal tar creosote, or creosote, is a by-product of the carbonization of coal to produce coke and has been used as a wood preservative since the late 19th century. Creosote is a mixture of many different compounds such as polycyclic aromatic hydrocarbons (PAH)s, phenols and cresols. Even though several PAHs are carcinogenic to humans, creosote is still used in impregnation of railway ties and electricity and telephone poles. Occupational exposure can occure from inhalation of creosote vapour or through skin contact. Dermal uptake is considered to be the most important route of exposure to PAHs. Even though the ratio between different PAHs may vary, measurements of 1-hydroxy-pyrene (1-HP) in urine is the common method for biological monitoring of occupational exposure to PAH. This study was conducted indoors in a facility where railroad switches are assembled with concrete or creosote impregnated wood ties. The aim of the study was to assess the workers´exposure to PAHs by (i) measuring PAH 16 in the breathing zone from whole shift samples, (ii) examining the dermal exposure of pyrene using a tape stripping technique, (iii) assessing the workers´ internal exposure by measuring 1-OHP in urine samples. The study show that during construction of railroad switches made from creosote impregnated ties workers get urinary levels of 1-OPH above the Biological Guidance Value during the work week. Dermal uptake seems to be the main route of exposure and preventive measures should be focused upon reducing the dermal exposure.
Speaker Biography
Pål Graff works as a Professor at the Norwegian National Institute of Occupational Health and Norwegian University of Life Sciences. His main research interests are exposure assessment and epidemiology.
136 Occupational Exposure to Asbestos
Authors: Ervik Torunn , Hammer Stine Eriksen , Skaugset Nils Petter , Graff Pål 
Published: May 2023

Abstract
Asbestos containing materials (ACMs) are still found in many buildings even though the use of asbestos in building materials has been prohibited in Norway since 1985. Employees that may be at risk of exposure to airborne fibers are workers within the construction industry. However, firefighters and workers investigating fires may also encounter asbestos fibers in their work. The aim of this study was to investigate the airborne fiber concentration during abatement of various ACMs. A comparison of counting results from scanning electron microscope (SEM) and phase-contrast microscope (PCM) were performed for these measurements. A separate part of the study focused on thermal transformation of fibers during fires. Parallel personal air samples were collected during asbestos abatement of different building materials and analyzed with SEM and PCM, respectively. Material samples from abatement sites and from fire scenes were investigated in SEM. The highest fiber concentrations were measured during interior wall removal (1.5-4.5 fibers/cm3 (f/cm3)). Thin fibers (&lt;0.2 µm in width) constituted up to 50% of the total fiber concentration for some ACMs. Asbestos fibers observed in ACMs after fire may show a thermal transformation, however, in many cases the fibers are unchanged. For ACMs investigated in this study, there seem to be a good correlation between samples analyzed by SEM and PCM if the only dominant fiber type present is asbestos fibers. Thin fibers may constitute a large fraction of the total fiber concentration released and counting these fibers are therefore important for an adequate risk and exposure assessments.
142 Gas Phase Polycyclic Aromatic Hydrocarbon Exposure in Kenyan Households
Authors: Forbes Patricia , Osano Aloys , Maghanga Justin 
Published: May 2023

Abstract
A vast number of people in developing countries rely on solid fuels, including wood and charcoal, for domestic energy supply. We have studied the gaseous polycyclic aromatic hydrocarbon (PAH) concentrations in Kenyan homes in order to better understand the potential health risks associated with domestic combustion practices and to advise mitigation strategies. A comprehensive survey was conducted to elucidate the complex and multi-faceted factors governing fuel use in Kenyan coastal and inland regions. Results showed an almost equal distribution in fuel type usage between firewood, charcoal, kerosene and liquid petroleum gas (LPG). In rural areas, three-stone stoves were still predominant, whilst cleaner devices burning kerosene and LPG were used more widely in urban communities. Indoor air was subsequently sampled in a range of urban and rural households using portable polydimethylsiloxane sampling tubes. These were extracted using the plunger assisted solvent extraction (PASE) technique, followed by GC-MS analysis of the U.S. Environmental Protection Agency (EPA) priority PAHs. Total PAH concentrations in samples collected varied considerably (0.82 – 173.69 µg/m3), which could be attributed to differences in fuel type, combustion device, climate, and nature of the households. Higher [PAH] were found in rural homes, although ambient PAH concentrations were higher in urban environments, likely due to traffic contributions and population density. Toxicity equivalent quotient values varied widely between households and emphasised the importance of good combustion practices to minimise human exposure.
14 Carcinogenicity Risk Assessment of Various Carbon Nanotubes by Intra-Tracheal Intra-Pulmonary Spray (TIPS) Dosing Followed by 2-Year Observation
Authors: Tsuda Hiroyuki , Ahmed Omnia , Saleh Dina , Alexander William , Alexander David , Numano Takamasa , Takase Hiroshi , Naiki-Ito Aya , Hirose Akihiko , Kanno Jun , Yudasaka Masako , Yuge Ryota , Tomono Susumu , Wei Min , Hojo Motoki , Tsuruoka Shuji 
Published: May 2023

Abstract
Multi-walled carbon nanotubes (MWCNTs) are composed of multiple coaxially arranged graphene cylinders. MWCNTs range in diameter from 1 to over 100 nm depending on the number of constituting graphene cylinders. MWCNTs can be divided into two general subtypes, straight and tangled: increasing the number of constituent graphene cylinders increases the number of layers that compose the carbon nanotube wall, and as the number of wall layers increase, the wall thickness increases and the MWCNT becomes more rigid and straight. MWCNTs with a low number of wall layers are flexible and can assemble into tangled agglomerates. We initially showed MWCNT-N, a straight-type MWCNT with 30-40 walls, induced lung tumors and mesotheliomas after administration by intra-tracheal intra-pulmonary spraying (TIPS): rats were administered a total dose of 1mg/rat during the initial 2 weeks of the study, and animals were observed for 2 years without any further treatments. Using this short-term dosing and 2-year observation method we conducted carcinogenicity tests for other MWCNTs with different cylinder wall layers. We found that both straight type MWCNTs, MWCNT-7 (40 layers), MWCNT-A (150 layers), and tangled type MWCNTs, MWCNT-B (15 layers) and double-walled CNT (DWCNT) (2 layers) induced lung tumors and/or pleural mesotheliomas. In contrast to these results, we found carbon nanohorns, carbon nanostructures composed of single-walled carbon nanotubes (SWCNT), and carbon nanobrushes, a fibrous aggregate of carbon nanohorns, were not carcinogenic. Data on foreign body radical production, microarray and mutational signature analyses, and gene alterations will be presented.
17 Effects of Indoor Air Pollution on Both a Healthy and “an Inflamed” Model of the Alveolar Barrier in Vitro.
Authors: Meldrum Kirsty , Evans Stephen J , Burgum Michael J , Doak Shareen H , Clift Martin J D 
Published: May 2023

Abstract
Exposure to indoor air pollutants (IAP) has increased recently, with people spending more time indoors. Increased exposures of IAP on a healthy population are poorly understood, and those with allergic respiratory conditions less so. The objective of this study, therefore, was to implement a well-characterised in vitro model of the human alveolar epithelial barrier (A549+PMA differentiated THP-1 incubated with/without IL-13, IL-5 and IL-4) to determine the effects of a standardised indoor particulate (NIST2583) on both a healthy lung model and modelling a type-II inflammatory response. Using concentrations from the literature, and an environmentally appropriate exposure we investigated 232, 464 and 608ng/cm2 of NIST2583 respectively. Membrane integrity (blue dextran), viability (trypan blue), genotoxicity (micronucleus (Mn) assay) and (pro-) and (anti-)inflammatory effects (IL-6, IL-8, IL-33, and IL-10) were then assessed 24hours post exposure to both models. No changes in Mn frequency or membrane integrity in either model was noted when exposed to any concentration of NIST2583 tested. Though, a significant decrease (p&lt;0.05) in viability at the highest concentration was observed in the healthy model. Whilst cell viability in the “inflamed” model significantly decreased (p&lt;0.05) at the lower concentrations. A significant reduction (p&lt;0.05) in IL-10 and increase in IL-33 was seen after exposure to NIST2583 in the “inflamed” model. Collectively, the results indicate the potential for IAP to cause the onset of an allergic response as well as exacerbating pre-existing allergic conditions. Furthermore, the data imposes the importance of considering unhealthy individuals when investigating the potential health effects of IAP.
20 An Approach Towards in Vitro-Based Human Toxicity Effect Factors for the Life Cycle Impact Assessment of Inhaled Low-Solubility Particles.
Authors: Romeo Daina , Hischier Roland , Nowack Bernd , Wick Peter 
Published: May 2023

Abstract
Life Cycle Assessment (LCA) calculations of products containing nanomaterials are limited in their comprehensiveness by the lack of characterization factors linking nanomaterial emissions to their impacts on human health. This is mainly due to the scarcity of animal toxicological data compared to the number of existing nanomaterials, a constraint that could be lifted if in vivo data could be substituted by in vitro data to calculate nanomaterials' effect factors (EF). To support a future animal-independent LCA methodology, we present a step-by-step procedure to calculate in vitro-to-in vivo extrapolation factors to estimate human Benchmark Doses and subsequently in vitro-based EFs for inhaled non-soluble nanomaterials. Titanium dioxide, amorphous silica, cerium oxide and crystalline silica are presented as case studies. Based on mouse data, the in vitro-based EF of TiO2 is between 2.76*10-4 and 1.10*10-3 cases/(m2/g *kg intake), depending on the aerodynamic size of the particle, which is in good agreement with in vivo-based EFs (1.51*10-4 - 5.6*10-2 cases/(m2/g *kg intake)). The EF for amorphous silica is in a similar range as for TiO2, but the result is less robust due to only few in vivo data available. The discrepancy between in vivo and animal in vitro data in terms of availability and quality limits the coverage of further nanomaterials. While the work focused on LCA, the procedure can be easily adapted for risk assessment as well, thus increasing the relevance of our findings.
25 Using Advanced in Vitro Approaches to Elucidate the Differential Toxicity of Nitrogen Dioxide and Particulate Matter in Ambient Air Pollution
Authors: Bateman Joshua , Robertson Sarah , Buckley Alison , Wright Matthew , Guo Chang , Leonard Martin O , Doak Shareen H , Smith Rachel , Clift Martin J D 
Published: May 2023

Abstract
Ambient nitrogen dioxide (NO2) and particulate matter (PM) concentrations are often found to be proportional, such that inhalation of one pollutant is expected to be accompanied by the inhalation of the other. Epidemiological evidence consistently demonstrates the health burdens associated with the inhalation of NO2 and PM, though has difficulty deciphering the inhalation hazard of either pollutant individually. Airway models can be exposed to NO2 and PM separately or as a co-exposure in vitro, allowing mechanisms of toxicity to be elucidated. Herein, NCI-H441 cells were exposed to either 780 ng/cm2 Printex 90 carbon black (CB) (a surrogate model of PM) using a VitroCell Cloud12, 5 ppm NO2 (within a modified Coy hypoxic cabinet) or a combination of NO2+CB over 24 hours. Cytotoxicity was not altered by NO2 or CB (trypan blue exclusion assay), however CB, and to a lesser extent CB+NO2 exposure resulted in a non-significant increase in membrane permeability (p&gt;0.05). qPCR revealed no alterations in expression of superoxide dismutase 1 (SOD1) for any exposure condition. Both CB and NO2 exposures resulted in significantly increased IL6 and IL8 release (ELISA) (p&lt;0.05), although co-exposure of the two pollutants did not augment the detected IL6 or IL8 levels. These data indicate NO2 and CB produce an inflammatory response in this model, though little evidence suggests that NO2 and CB act in an additive or synergistic manner via this pathway. Additional work remains ongoing to establish the mechanisms of toxicity utilising an anatomically relevant triple cell co-culture of the alveolar epithelial barrier.
35 2D-Hexagonal Boron Nitride and Lung Exposure: Exploring Long-Term Effects in Healthy Versus Asthmatic Human Lung in Vitro Model
Authors: Gupta Govind , Wick Peter , Buerki-Thurnherr Tina 
Published: May 2023

Abstract
Inhalation is one of the most pertinent routes of exposure to nanoscale materials in occupational settings. Hexagonal boron nitride (hBN) is an emerging 2D material attracting significant attention due to its superior electrical, chemical, and thermal properties. For a successful commercial application of 2D-hBN, it is of key importance to understand their safety in occupational settings. However, long-term toxicity profile of this material is largely unknown. Here, an investigation of how 2D-hBN (obtained from Graphene Flagship consortium) interacts with lung cells of healthy versus diseased individuals has been performed. We used air−liquid interface-based exposure models to investigate the potential long-term toxicity of 2D-hBN in human lung airway epithelial cells (Calu-3) and 3D reconstituted airway epithelia (MucilairTM) of healthy and asthmatic subjects. Our results revealed that 2D-hBN was taken up by cells but did not trigger cytotoxicity at occupationally relevant repeated dose exposure for five weeks. However, screening of an immuno-cytokine/chemokine panel indicated an enhanced release of certain cytokines after exposure to 2D-hBN. In addition, we observed a pronounced intracellular accumulation of lipids in lipid droplets after exposure to 2D-hBN. Since lipid intermediates can play important roles in immune-cell activation and the development of lung diseases, we are currently analysing whether 2D-hBN induces alterations in lipid composition in healthy and asthmatic cells by applying global lipidomic profiling. Overall, our data indicate a potential correlation of certain lipid accumulation with enhanced immune signaling, highlighting the need for further studies to understand if 2D-hBN can sensitize for or aggravate pulmonary diseases.
46 Solubility and the Toxicity of Metal Oxide Nanoparticles: Looking Through the Lens of Toxicogenomics and DNA Damage
Authors: Boyadzhiev Andrey , Solorio-Rodriguez Silvia Aidee , Avramescu Mary-Luyza , Wu Dongmei , Williams Andrew , Rasmussen Pat , Halappanavar Sabina 
Published: May 2023

Abstract
Metal oxide nanoparticles (MONPs) are amongst the most widely utilized classes of nanomaterials worldwide. The mechanisms underlying their pulmonary toxicity are dependant on the physical-chemical properties of the particles. Solubility plays a critical role, as proportions of nanoparticles and dissolved metals change over time; however their relative contribution to the resulting toxicity has yet to be thoroughly investigated. The objective of this study was to mechanistically evaluate the impact of solubility on the toxic potential of MONPs. In this study, mouse lung epithelial cells were exposed for 2 – 48 Hrs to copper, zinc, nickel, aluminum and titanium oxides (CuO, ZnO, NiO, Al2O3, TiO2) as MONPs and microparticles, and corresponding metal chloride salts. Viability was assessed at each timepoint using Trypan Blue staining. DNA damage was measured after 2 and 4 Hrs exposure via the CometChip assay, while transcriptomic changes were measured using microarrays after 2, 24, and 48 Hrs of exposure. Benchmark dose modelling of viability and transcriptomics data indicates that ZnO and CuO MONPs induced more pronounced cytotoxicity and gene expression, earlier, than NiO, Al2O3, and TiO2 MONPs. With respect to DNA damage potential, NiO, CuO and ZnO MONPs showed the highest potency, with ZnCl2 being the only chloride to induce DNA damage at either timepoint. The metal chlorides induced similar pathway perturbations as their respective MONPs, while corresponding microparticle oxides (except ZnO microparticles) exhibited muted responses. This presentation will further explore these findings, with an emphasis on the effect of solubility on toxicity.
65 The Adverse Health Effects of Exposure to PM2.5 on the London Underground
Authors: Mak Justie , Cullinan Paul , Feary Johanna , Marczylo Emma , Amaral André F S , Green David 
Published: May 2023

Abstract
Transport for London (TfL) employed 36,506 staff between 2014 and 2019, 22,202 worked within the London Underground (LU). Employees were regularly exposed to PM2.5 concentrations 15-fold higher than those found above ground in London. However, PM2.5 in the LU differs in physical and chemical characteristics relative to outdoor air, and the health impacts are largely unquantified. This project aims to quantify LU PM exposure of staff and measure its impact on cardiorespiratory sickness absence. A job exposure matrix was developed to model TfL employee PM2.5 exposure based on their jobs. Measurement campaigns were deployed across the LU network to validate and revise staff PM2.5 exposure, which was then linked to sickness absence records. Poisson models were developed to explore the relationship with cardiorespiratory sickness absence. PM2.5 exposure of customer service staff varied depending on their grade and tasks they undertake. Concentrations ranged from 2 to 138 µg/m3 in the offices and 3 to 1,036 µg/m3 on the platforms. Drivers’ PM2.5 exposure was dependent on the line they worked on and the amount of time the train spent underground. Drivers have the highest PM2.5 exposure (median: 130 µg/m3) among all TfL staff and the highest mean number of all-cause (6.7) and respiratory (1.5) sickness absence episodes. This is the largest study to quantify LU PM exposure and the associated health effects within a London occupational cohort. It will contribute to a safer working environment for staff and to a better understanding of the potential health impact on the commuting population.
71 Metabolomics Study of a Lung Model Exposed to Different Ultrafine Particles (UFP) Aerosols
Authors: Alsaleh Rasha , Kersch Christian , Pantzke Jana , Das Anusmita , Delaval Mathilde N , Sklorz Martin , Bucchianico Sebastiano Di , Zimmermann Ralf , Schmitz-Spanke Simone 
Published: May 2023

Abstract
Ultrafine particles (UFP), diameter of &lt;0.1 µm, contribute to urban particulate air pollution. There is still not much evidence on their effects on humans. Our study aims to address their possible effects on lung metabolome.
Alveolar epithelial cells (A549) together with macrophages (THP-1) were seeded on the apical side of the insert membrane, and fibroblasts (MRC-5) on the downside, respectively. Triple cell cultures were exposed at the air liquid interface to different aerosols generated by a combustion aerosol standard (CAST) soot generator. Applied aerosols consisted of UFP with either high or low content of semi-volatile organic compounds (SVOC). Herein, apical cell lysates were extracted for metabolites. Data acquisition was performed by GC-MS and processed with R and then analyzed by MetaboAnalyst. Statistical analysis showed that top features differentiating the high SVOC from clean air controls were amino acids (L-tryptophan and L-lysine), whereas for low SVOC, 5-methylthioadenosine and 5-methoxyindoleacetate. Tryptophan and its metabolite 5-hydroxy- tryptophan were significantly upregulated in high SVOC. However, in low SVOC, 5-methoxyindoleacetate was substantially upregulated. Pathway analysis revealed that purine metabolism was between the top significant enriched pathways in both high and low SVOC groups. Moreover, tryptophan metabolism which modulates immunity and inflammation was enriched similarly in both groups. These findings suggest that lung cell metabolome is modulated distinctively based on the chemical identity of UFP, which could give more understanding about the lung response mechanism to inhaled UFP.
This work was funded by Bayerische Staatsministeriums für Umwelt und Verbraucherschutz (BayUFP).
72 Endotoxin Exacerbates the NLRP3-Dependent Inflammatory Potency of Saharan Dust
Authors: Bredeck Gerrit , Busch Mathias , Rossi Andrea , Stahlmecke Burkhard , Fomba Khanneh Wadinga , Herrmann Hartmut , Schins Roel P F 
Published: May 2023

Abstract
Epidemiological studies have shown that desert dust exposure affects respiratory health. We aimed to investigate the NLRP3 inflammasome-caspase-1 pathway-dependent inflammatory properties of Saharan dust (SD) in a macrophage model and an air-liquid interface (ALI) co-culture model of the alveolar epithelium. Under submerged conditions wild-type (WT) and NLRP3-/- THP-1 cells were exposed to SD at 50 µg/cm². Using a Vitrocell® Cloud, A549/THP-1 WT ALI co-cultures were exposed to SD or DQ12 quartz at non-cytotoxic concentrations of 10, 20, and 30 µg/cm². Additionally, ALI co-cultures containing NLRP3-/- or CASPASE1/- THP-1 cells were exposed to SD. SD was found to contain endotoxin, and caused manifold higher interleukin (IL)-1β secretion in WT than in NLRP3/- THP-1 cells. Baked SD (220°C, overnight) induced IL-1β secretion to a ~4-fold lower extent. Co-exposure to baked SD and endotoxin synergistically restored the IL-1β secretion. In ALI co-cultures SD but not DQ12 upregulated the expression and secretion of IL-1β, IL-6, IL-8, and tumor necrosis factor α. The secretion of these cytokines was strongly decreased in co-cultures with CASPASE1/- or NLRP3/- THP-1 cells. The screening of multiple SD samples on WT THP-1 cells revealed that their inflammatory potencies strongly depended on the sampling day and location. The surprisingly strong SD-mediated activation of the NLRP3 inflammasome emphasizes its hazardousness and the need for risk mitigation strategies. Therefore, the connection between the toxicity of SD and its composition, especially its microbial components, needs to be further unraveled.
Supported by the Leibniz Collaborative Excellence Programme project DUSTRISK.