Early Effect Markers and Exposure Determinants of Metalworking Fluids Among Metal Industry Workers: Protocol for a Field Study.

Exposure to aerosols from metalworking fluids (MWF) has previously been related to a series of adverse health outcomes (eg, cancer, respiratory diseases). Our present epidemiological study focuses on occupational exposures to MWF and a panel of exposure and effect biomarkers. We hypothesize that these health outcomes are caused by particle exposure that generates oxidative stress, leading to airway inflammation and ultimately to chronic respiratory diseases. We aimed to assess whether MWF exposure, in particular as characterized by its oxidative potential, is associated with biomarkers of oxidative stress and inflammation as well as genotoxic effects. The ultimate goal is to develop exposure reduction strategies based on exposure determinants that best predict MWF-related health outcomes. The following relationships will be explored: (1) exposure determinants and measured exposure; (2) occupational exposure and preclinical and clinical effect markers; (3) exposure biomarkers and biomarkers of effect in both exhaled breath condensate and urine; and (4) biomarkers of effect, genotoxic effects and respiratory symptoms. At least 90 workers from France and Switzerland (30 controls, 30 exposed to straight MWF and 30 to aqueous MWF) were followed over three consecutive days after a nonexposed period of at least two days. The exposure assessment is based on MWF, metal, aldehyde, and ultrafine particle number concentrations, as well as the intrinsic oxidative potential of aerosols. Furthermore, exposure biomarkers such as metals, metabolites of polycyclic aromatic hydrocarbons and nitrosamine are measured in exhaled breath condensate and urine. Oxidative stress biomarkers (malondialdehyde, 8-isoprostane, 8-hydroxy-2'-deoxyguanosine, nitrates, and nitrites) and exhaled nitric oxide, an airway inflammation marker, are repeatedly measured in exhaled breath condensate and urine. Genotoxic effects are assessed using the buccal micronucleus cytome assay. The statistical analyses will include modelling exposure as a function of exposure determinants, modelling the evolution of the biomarkers of exposure and effect as a function of the measured exposure, and modelling respiratory symptoms and genotoxic effects as a function of the assessed long-term exposure. Data collection, which occurred from January 2018 until June 2019, included 20 companies. At the date of writing, the study included 100 subjects and 29 nonoccupationally exposed controls. This study is unique as it comprises human biological samples, questionnaires, and MWF exposure measurement. The biomarkers collected in our study are all noninvasive and are useful in monitoring MWF exposed workers. The aim is to develop preventative strategies based on exposure determinants related to health outcomes. DERR1-10.2196/13744

Method validation of nanoparticle tracking analysis to measure pulmonary nanoparticle content: the size distribution in exhaled breath condensate depends on occupational exposure

A particle exposure assessment based on the dose deposited in the lungs would be the gold standard for the evaluation of any resulting health effects. Measuring particles in exhaled breath condensate (EBC)-a matrix containing water and airway lining fluid-could help to evaluate particle retention in the lungs. This study aimed to (1) validate a nanoparticle tracking analysis (NTA) method for determining the particle number concentration and their hydrodynamic size distribution in EBC, and (2) apply this method to EBC collected from workers exposed to soapstone (n = 55) or quartz dust (n = 12) and controls (n = 11). A standard latex bead solution was used to determine the linear range, limit of detection (LOD), repeatability (coefficient of variation, CV), and bias in spiked EBC. An LM10 NanoSight instrument with NTA version 3.1 software was used for measurement. RTubes(®) were used for field collection of EBC. The repeatability obtained for a D50 size distribution in EBC showed less than 8% variability, with a bias <7%. The particle concentration was linear in the range ≤2.5 × 10(8) particles ml(-1) with a LOD of 4 × 10(6) particles ml(-1). A recovery of 117 ± 20% at 6.2 × 10(7) particles ml(-1) was obtained with a CV <10% and a bias <20%. EBC from workers exposed to quartz, who experienced the largest exposure to silica particles, consistently exhibited a statistically significant (p < 0.01) higher concentration of particles in their EBC, with a size distribution shift towards larger values than the other groups. Results showed that the NTA technique performed well for characterizing the size distribution and concentrations of particles in EBC. The technique needs to be corroborated with a larger population of workers

Does exposure to inflammatory particles modify the pattern of anion in exhaled breath condensate?

Exposure to environmental and occupational particulate matter (PM) induces health effects on the cardio-pulmonary system. In addition, associations between exposure to PM and metabolic syndromes like diabetes mellitus or obesity are now emerging in the literature. Collection of exhaled breath condensate (EBC) is an appealing non-invasive technique to sample pulmonary fluids. This hypothesis-generating study aims to (1) validate an ion chromatography method allowing the robust determination of different metabolism-related molecules (lactate, formate, acetate, propionate, butyrate, pyruvate, nitrite, nitrate) in EBC; (2) apply this method to EBC samples collected from workers exposed to quartz (a known inflammatory particle), to soapstone (a less inflammatory particle than quartz), as well as to controls. A multi-compound standard solution was used to determine the linearity range, detection limit, repeatability and bias from spiked EBC. The biological samples were injected without further treatment into an ion chromatograph with a conductivity detector. RTube <sup>®</sup> were used for field collection of EBC from 11 controls, 55 workers exposed to soapstone and 12 volunteers exposed to quartz dust. The analytical method used proved to be adequate for quantifying eight anions in EBC samples. Its sub-micromolar detection limits and repeatability, combined with a very simple sample preparation, allowed an easy and fast quantification of different glycolysis or nitrosative stress metabolites. Using multivariate discriminant analysis to maximize differences between groups, we observed a different pattern of anions with a higher formate/acetate ratio in the EBC samples for quartz exposed workers compared to the two other groups. We hypothesize that a modification of the metabolic signature could be induced by exposure to inflammatory particles like quartz and might be observed in the EBC via a change in the formate/acetate ratio

Analysis of nitrogen oxides (NOx) in the exhaled breath condensate (EBC) of subjects with asthma as a complement to exhaled nitric oxide (FeNO) measurements: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>The study of pulmonary biomarkers with noninvasive methods, such as the analysis of exhaled breath condensate (EBC), provides a useful approach to the pathophysiology of asthma. Although many recent publications have applied such methods, numerous methodological pitfalls remain. The first stage of our study consisted of validating methods for the collection, storage and analysis of EBC; we next sought to clarify the utility of analysing nitrogen oxides (NOx) in the EBC of asthmatics, as a complement to measuring exhaled nitric oxide (FeNO).</p> <p>Methods</p> <p>This hospital-based cross-sectional study included 23 controls matched with 23 asthmatics. EBC and FeNO were performed and respiratory function measured. Intra-assay and intra-subject reproducibility were assessed for the analysis of NOx in the EBC of 10 healthy subjects.</p> <p>Results</p> <p>The intraclass correlation coefficient (ICC) was excellent for intra-assay reproducibility and was moderate for intra-subject reproducibility (Fermanian's classification). NOx was significantly higher in asthmatics (geometric mean [IQR] 14.4 μM [10.4 - 19.7] vs controls 9.9 μM [7.5 - 15.0]), as was FeNO (29.9 ppb [17.9 - 52.4] vs controls 9.6 ppb [8.4 - 14.2]). FeNO also increased significantly with asthma severity.</p> <p>Conclusions</p> <p>We validated the procedures for NOx analysis in EBC and confirmed the need for assays of other biomarkers to further our knowledge of the pathophysiologic processes of asthma and improve its treatment and control.</p

Évaluation méthodologique et clinique des marqueurs de l’atteinte pulmonaire dans l’air exhalé : comparaison de sujets présentant une pathologie respiratoire chronique et sujets témoins

The study of both volatile (FeNO) and non-volatile respiratory biomarkers using the method of exhaled breath condensates can be useful in medical surveillance of exposed workers, the early identification of respiratory diseases or in the monitoring of their development. Studies of exhaled NO (FeNO) is now well standardized and the exponential increase in publications on exhaled breath condensate (EBC) reflects growing interest in a non-invasive diagnosis of pulmonary diseases. The biomarkers studied are products of inflammation, such as FeNO and cytokines, and products of oxidative stress, including hydrogen peroxide (H202), products of lipid peroxydation (8-isoprostane, malondialdehyde) and nitrogen oxides. The first recommendation was published in 2005 but although many recent publications have applied this new method, numerous methodological pitfalls remain and still described in 2012. They concern all the stages of the collection to the analysis.Objectives: The main objective of this research was initially to develop the method of EBC for the study of compounds of exhaled air and then detect and quantify biomarkers such as total protein, NOx and 8-isoprostane in exhaled air in a population of healthy adults (n = 48) or patients with lung inflammatory diseases such as asthma (n = 24), COPD (n = 20), diffuse interstitial pneumonia (n = 27) and scleroderma (n = 27). The secondary objective was to compare levels of biomarkers measured in the EBC and FeNO in patients compared to controls.Results / conclusion: Our research, supported by ANR and ANSES, allowed to standardize the methodology of collection and analysis of EBC with a choice of the collection system and coating which must be effective and compatible with the analyzes. In EBC, we control the dosage of biomarkers such as proteins, NOx and 8-isoprostane. Other biomarkers are still being studied such as malondialdehyde and cytokines. This published methodological study, allowed in a second step the detection (> 95%) and quantification of these biomarkers in EBC of healthy patients in our population.Perspectives: This standardization is a key epidemiological requirement for the task force on the establishment of reference values and the publication of methodological guidelines so as to realize the promise of this approach for clinical studies of lung diseases. We have also to finish the development of biomarkers such as cytokines or malondialdehyde and to investigate new biomarkers to complete the pathophysiological mechanisms. Finally our objective is the widespread use of this noninvasive method in daily epidemiological studies on subjects with professional and/or environmental exposure. In this context, the study of markers of the toxic burden in the lungs such as heavy metals in the EBC is being developed.Un accès direct et non invasif à la pathogénèse par l’évaluation de biomarqueurs volatils (FeNO) ou non volatils de l’air exhalé grâce à la méthode des condensats de l’air exhalé (EBC) est utile pour estimer précocement le degré d’atteinte pulmonaire en rapport avec une exposition professionnelle et surveiller son évolution en regard des mesures correctives mises en place. L’étude du NO exhalé (FeNO) est actuellement bien standardisée et l’augmentation exponentielle des publications concernant les EBC reflètent un intérêt croissant pour le diagnostic non invasif des atteintes pulmonaires. Les marqueurs étudiés dans l’air exhalé sont des produits de l'inflammation tels que le FeNO et les cytokines ainsi que des produits du stress oxydant incluant le peroxyde d'hydrogène, les produits de peroxydation lipidique (8-isoprostane, malondialdehyde) et les oxydes d'azote (NOx). S’agissant d’une technique d’exploration relativement récente, les modalités méthodologiques font encore l’objet de nombreux travaux, les premières recommandations internationales étant apparues en 2005. Les écueils méthodologiques sont nombreux et encore décrits dans la littérature en 2012. Ils concernent toutes les étapes du processus du recueil et d’analyses.Objectifs : L’objectif principal de notre recherche était dans un premier temps de développer la méthode des EBC pour l'étude des composés de l'air exhalé puis de détecter et quantifier des biomarqueurs tels que les protéines totales, les NOx et le 8-isoprostane dans les EBC d’une population d’adultes sains (n= 48) ou atteints de pathologies pulmonaires telles que l'asthme (n=24), la BPCO (n=20), la pneumopathie interstitielle diffuse (n=27) et la sclérodermie (n=27). L’objectif secondaire était la comparaison des niveaux de biomarqueurs dosés dans les EBC et du FeNO chez les sujets malades par rapport aux témoins.Résultats / Conclusion : Notre recherche, soutenue l’ANR et l’ANSES, a permis de standardiser la méthodologie de recueil et d’analyse des EBC avec une optimisation du système de recueil et de l’agent coatant pour la détermination de la concentration nécessaire et compatible avec les analyses. Nous maitrisons le dosage dans les EBC des biomarqueurs tels que les protéines, les NOx et le 8-isoprostane. D'autres biomarqueurs sont encore en cours d'étude tels que le malondialdehyde et les cytokines. Ce travail méthodologique, publié, a permit dans un second temps la détection (> à 95%) et la quantification de ces biomarqueurs dans les EBC des sujets sains et malades de notre population.Perspectives : La constitution des valeurs de référence pour les biomarqueurs dosés dans les EBC est nécessaire à l’interprétation des dosages chez les sujets malades. Il convient également de finaliser la standardisation de la mesure des cytokines et du malondialdehyde et d’explorer de nouveaux biomarqueurs produits lors du stress nitrosant tels que la 3-nitrotyrosine pour compléter les mécanismes physiopathologiques. Enfin le développement de cette méthode non invasive et peu contraignante apparait prometteuse en clinique médicale dans le suivi individuel de la maladie ou son traitement comme lors d’études épidémiologiques respiratoires dans des populations exposées professionnellement ou environnementalement. Dans ce cadre, l’étude de marqueurs d’exposition professionnelle tels que les métaux lourds dans les EBC est en cours de développement

Methodological and clinical evaluation of markers of the lung injury in exhaled breath : comparison of subjects with chronic respiratory disease and controls

Un accès direct et non invasif à la pathogénèse par l’évaluation de biomarqueurs volatils (FeNO) ou non volatils de l’air exhalé grâce à la méthode des condensats de l’air exhalé (EBC) est utile pour estimer précocement le degré d’atteinte pulmonaire en rapport avec une exposition professionnelle et surveiller son évolution en regard des mesures correctives mises en place. L’étude du NO exhalé (FeNO) est actuellement bien standardisée et l’augmentation exponentielle des publications concernant les EBC reflètent un intérêt croissant pour le diagnostic non invasif des atteintes pulmonaires. Les marqueurs étudiés dans l’air exhalé sont des produits de l'inflammation tels que le FeNO et les cytokines ainsi que des produits du stress oxydant incluant le peroxyde d'hydrogène, les produits de peroxydation lipidique (8-isoprostane, malondialdehyde) et les oxydes d'azote (NOx). S’agissant d’une technique d’exploration relativement récente, les modalités méthodologiques font encore l’objet de nombreux travaux, les premières recommandations internationales étant apparues en 2005. Les écueils méthodologiques sont nombreux et encore décrits dans la littérature en 2012. Ils concernent toutes les étapes du processus du recueil et d’analyses.Objectifs : L’objectif principal de notre recherche était dans un premier temps de développer la méthode des EBC pour l'étude des composés de l'air exhalé puis de détecter et quantifier des biomarqueurs tels que les protéines totales, les NOx et le 8-isoprostane dans les EBC d’une population d’adultes sains (n= 48) ou atteints de pathologies pulmonaires telles que l'asthme (n=24), la BPCO (n=20), la pneumopathie interstitielle diffuse (n=27) et la sclérodermie (n=27). L’objectif secondaire était la comparaison des niveaux de biomarqueurs dosés dans les EBC et du FeNO chez les sujets malades par rapport aux témoins.Résultats / Conclusion : Notre recherche, soutenue l’ANR et l’ANSES, a permis de standardiser la méthodologie de recueil et d’analyse des EBC avec une optimisation du système de recueil et de l’agent coatant pour la détermination de la concentration nécessaire et compatible avec les analyses. Nous maitrisons le dosage dans les EBC des biomarqueurs tels que les protéines, les NOx et le 8-isoprostane. D'autres biomarqueurs sont encore en cours d'étude tels que le malondialdehyde et les cytokines. Ce travail méthodologique, publié, a permit dans un second temps la détection (> à 95%) et la quantification de ces biomarqueurs dans les EBC des sujets sains et malades de notre population.Perspectives : La constitution des valeurs de référence pour les biomarqueurs dosés dans les EBC est nécessaire à l’interprétation des dosages chez les sujets malades. Il convient également de finaliser la standardisation de la mesure des cytokines et du malondialdehyde et d’explorer de nouveaux biomarqueurs produits lors du stress nitrosant tels que la 3-nitrotyrosine pour compléter les mécanismes physiopathologiques. Enfin le développement de cette méthode non invasive et peu contraignante apparait prometteuse en clinique médicale dans le suivi individuel de la maladie ou son traitement comme lors d’études épidémiologiques respiratoires dans des populations exposées professionnellement ou environnementalement. Dans ce cadre, l’étude de marqueurs d’exposition professionnelle tels que les métaux lourds dans les EBC est en cours de développement.The study of both volatile (FeNO) and non-volatile respiratory biomarkers using the method of exhaled breath condensates can be useful in medical surveillance of exposed workers, the early identification of respiratory diseases or in the monitoring of their development. Studies of exhaled NO (FeNO) is now well standardized and the exponential increase in publications on exhaled breath condensate (EBC) reflects growing interest in a non-invasive diagnosis of pulmonary diseases. The biomarkers studied are products of inflammation, such as FeNO and cytokines, and products of oxidative stress, including hydrogen peroxide (H202), products of lipid peroxydation (8-isoprostane, malondialdehyde) and nitrogen oxides. The first recommendation was published in 2005 but although many recent publications have applied this new method, numerous methodological pitfalls remain and still described in 2012. They concern all the stages of the collection to the analysis.Objectives: The main objective of this research was initially to develop the method of EBC for the study of compounds of exhaled air and then detect and quantify biomarkers such as total protein, NOx and 8-isoprostane in exhaled air in a population of healthy adults (n = 48) or patients with lung inflammatory diseases such as asthma (n = 24), COPD (n = 20), diffuse interstitial pneumonia (n = 27) and scleroderma (n = 27). The secondary objective was to compare levels of biomarkers measured in the EBC and FeNO in patients compared to controls.Results / conclusion: Our research, supported by ANR and ANSES, allowed to standardize the methodology of collection and analysis of EBC with a choice of the collection system and coating which must be effective and compatible with the analyzes. In EBC, we control the dosage of biomarkers such as proteins, NOx and 8-isoprostane. Other biomarkers are still being studied such as malondialdehyde and cytokines. This published methodological study, allowed in a second step the detection (> 95%) and quantification of these biomarkers in EBC of healthy patients in our population.Perspectives: This standardization is a key epidemiological requirement for the task force on the establishment of reference values and the publication of methodological guidelines so as to realize the promise of this approach for clinical studies of lung diseases. We have also to finish the development of biomarkers such as cytokines or malondialdehyde and to investigate new biomarkers to complete the pathophysiological mechanisms. Finally our objective is the widespread use of this noninvasive method in daily epidemiological studies on subjects with professional and/or environmental exposure. In this context, the study of markers of the toxic burden in the lungs such as heavy metals in the EBC is being developed

Analyse des biomarqueurs dans le condensat de l'air exhalé dans une population de salariés exposés professionnellement au béryllium et/ou ses composés

International audienceMétal incontournable dans les industries de pointe à fortes contraintes thermiques et mécaniques, le béryllium peut provoquer une bérylliose pulmonaire chronique (BPC), précédée par un état de sensibilisation au béryllium (SeBe). La valeur limite d’exposition professionnelle sur 8 heures actuellement en vigueur en France insuffisamment protectrice, l’augmentation prévisible du nombre de sujets professionnellement exposés, la latence longue d’apparition de la BPC et l’absence d’outils standardisés de surveillance médicale justifient l’intérêt d’étudier des biomarqueurs d’exposition et d’effets précoces au niveau de l’organe cible, le poumon. Cette étude propose de les mesurer dans le condensat de l’air exhalé, nouvelle matrice biologique

Beryllium in exhaled breath condensate as a biomarker of occupational exposure in a primary aluminum production plant

International audienc

Biomarkers of oxidative stress and antioxidants in severe asthma: A Prospective Case-Control Study.

BACKGROUND Bronchial airway inflammation is the hallmark of asthma, which may be driven by an imbalance between oxidative stress and antioxidant defenses. Antioxidants deficiency may play a role, but this has remained unconfirmed. OBJECTIVE To evaluate the oxidative stress burden and antioxidants defenses in patients with increasing asthma severity. METHODS This prospective case-control study compared fractional exhaled nitric oxide (FeNO), exhaled breath condensate nitrite/nitrate (EBC-NOx), spirometry, and serum vitamins and trace elements among patients with and without asthma. RESULTS Sixty participants were recruited (30 with severe asthma number; 23 women [76.7%]; mean age, 41.4 years; mean forced expiratory volume in 1 second [FEV1], 2.2 L [72.2% predicted]; mean inhaled corticosteroid dosage, 2,540 μg/d; 18/30 [60%] receiving maintenance oral corticosteroids; 15 with mild asthma; all corticosteroids naïve; 9 women [60%]; mean age, 34.6 years; mean FEV1, 3.48 L [100.5% predicted]; 15 healthy controls; 12 women [80%]; mean age, 37.6 years; and mean FEV1, 3.53 L [111.7% predicted]). The mean FeNO levels increased significantly with increasing asthma severity (P = .01), but the EBC-NOx levels did not change significantly (P = .90). Paradoxically, vitamin A and vitamin E increased with increased disease severity, with vitamin E levels increasing significantly (P = .07 and P < .001, respectively). There was no significant difference between groups in the levels of copper (P = .37), zinc (P = .97), or selenium (P = .90). CONCLUSION FeNO but not EBC-NOx is increased significantly with asthma severity with no evidence of vitamins or trace elements deficiency in severe asthma. Impaired oxidative stress defenses in severe asthma may be driven by factors other than vitamins or trace elements deficiency