Biomarkers In Exhaled Breath Condensate Research Articles

Discriminative potential of exhaled breath condensate biomarkers with respect to chronic obstructive pulmonary disease

BackgroundChronic obstructive pulmonary disease (COPD) affecting 334 million people in the world remains a major cause of morbidity and mortality. Proper diagnosis of COPD is still a challenge and largely solely based on spirometric criteria. We aimed to investigate the potential of nitrosative/oxidative stress and related metabolic biomarkers in exhaled breath condensate (EBC) to discriminate COPD patients.MethodsThree hundred three participants were randomly selected from a 15,000-transit worker cohort within the Respiratory disease Occupational Biomonitoring Collaborative Project (ROBoCoP). COPD was defined using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria as post-bronchodilator ratio of Forced Expiratory Volume in 1st second to Forced Vital Capacity < 0.7 in spirometry validated by an experienced pulmonologist. Discriminative power of biomarker profiles in EBC was analyzed using linear discriminant analyses.ResultsAmongst 300 participants with validated spirometry, 50.3% were female, 52.3 years old in average, 36.0% were current smokers, 12.7% ex-smokers with mean tobacco exposure of 15.4 pack-years. Twenty-one participants (7.0%) were diagnosed as COPD, including 19 new diagnoses, 12 of which with a mild COPD stage (GOLD 1). Amongst 8 biomarkers measured in EBC, combination of 2 biomarkers, Lactate and Malondialdehyde (MDA) significantly discriminated COPD subjects from non-COPD, with a 71%-accuracy, area under the receiver curve of 0.78 (p-value < 0.001), and a negative predictive value of 96%.ConclusionsThese findings support the potential of biomarkers in EBC, in particular lactate and MDA, to discriminate COPD patients even at a mild or moderate stage. These EBC biomarkers present a non-invasive and drugless technique, which can improve COPD diagnosis in the future.

Metal and oxidative potential exposure through particle inhalation and oxidative stress biomarkers: a 2-week pilot prospective study among Parisian subway workers

ObjectiveIn this pilot study on subway workers, we explored the relationships between particle exposure and oxidative stress biomarkers in exhaled breath condensate (EBC) and urine to identify the most relevant biomarkers for a large-scale study in this field.MethodsWe constructed a comprehensive occupational exposure assessment among subway workers in three distinct jobs over 10 working days, measuring daily concentrations of particulate matter (PM), their metal content and oxidative potential (OP). Individual pre- and post-shift EBC and urine samples were collected daily. Three oxidative stress biomarkers were measured in these matrices: malondialdehyde (MDA), 8-hydroxy-2′deoxyguanosine (8-OHdG) and 8-isoprostane. The association between each effect biomarker and exposure variables was estimated by multivariable multilevel mixed-effect models with and without lag times.ResultsThe OP was positively associated with Fe and Mn, but not associated with any effect biomarkers. Concentration changes of effect biomarkers in EBC and urine were associated with transition metals in PM (Cu and Zn) and furthermore with specific metals in EBC (Ba, Co, Cr and Mn) and in urine (Ba, Cu, Co, Mo, Ni, Ti and Zn). The direction of these associations was both metal- and time-dependent. Associations between Cu or Zn and MDAEBC generally reached statistical significance after a delayed time of 12 or 24 h after exposure. Changes in metal concentrations in EBC and urine were associated with MDA and 8-OHdG concentrations the same day.ConclusionAssociations between MDA in both EBC and urine gave opposite response for subway particles containing Zn versus Cu. This diverting Zn and Cu pattern was also observed for 8-OHdG and urinary concentrations of these two metals. Overall, MDA and 8-OHdG responses were sensitive for same-day metal exposures in both matrices. We recommend MDA and 8-OHdG in large field studies to account for oxidative stress originating from metals in inhaled particulate matter.

Sensitive detection of exhaled breath condensate inflammation biomarkers using boron nitride nanosheet/gold nanoparticle hybrids

An ultrasensitive electrochemical immunosensor using boron nitride nanosheet/gold nanoparticle (BNNS/AuNP) hybrids was developed for exhaled breath condensate (EBC) interleukin-6 (IL-6) quantification. BNNS were synthesized by chemical vapor deposition and decorated with AuNPs. The BNNS/AuNP hybrids were characterized by SEM, TEM, XRD, Raman, XPS, etc., and deposited on screen-printed carbon electrodes. Anti-IL-6 antibodies were immobilized via EDC/NHS crosslinking. The immunosensor detected IL-6 by differential pulse voltammetry technique with a linear range of 0.01–200 ng/mL and a limit of detection of 5 pg/mL. The sensor showed high reproducibility and selectivity. Validation with spiked EBC samples demonstrated good accuracy (relative error <5%). The sensor was successfully applied to analyze IL-6 in EBC samples. The BNNS/AuNP hybrid immunosensor provides a sensitive platform for non-invasive EBC biomarker quantification in respiratory diseases.

Advances in proteomics methods for the analysis of exhaled breath condensate.

The analysis of exhaled breath condensate (EBC) demonstrates a promising avenue of minimally invasive biopsies for diagnostics. EBC is obtained by cooling exhaled air and collecting the condensation to be utilized for downstream analysis using various analytical methods. The aqueous phase of breath contains a large variety of miscible small compounds including polar electrolytes, amino acids, cytokines, chemokines, peptides, small proteins, metabolites, nucleic acids, and lipids/eicosanoids-however, these analytes are typically present at minuscule levels in EBC, posing a considerable technical challenge. Along with recent improvements in devices for breath collection, the sensitivity and resolution of liquid chromatography coupled to online mass spectrometry-based proteomics has attained subfemtomole sensitivity, vastly enhancing the quality of EBC sample analysis. As a result, proteomics analysis of EBC has been expanding the field of breath biomarker research. We present an au courant overview of the achievements in proteomics of EBC, the advancement of EBC collection devices, and the current and future applications for EBC biomarker analysis.

DNA damage in workers exposed to pigment grade titanium dioxide (TiO2) and association with biomarkers of oxidative stress and inflammation

The present study was aimed at investigating DNA damage, micronuclei frequency and meta-nuclear alterations in buccal cells of workers involved in pigment-grade TiO2 production (15 exposed and 20 not-exposed). We also assessed associations of genotoxicity biomarkers with oxidative stress/inflammatory biomarkers in urine and exhaled breath condensate (EBC), as well as possible associations between biomarkers and reported respiratory symptoms. In spite of compliance with TiO2 Occupational Exposure Limits, results showed increased direct/oxidative DNA damage and micronuclei frequency in exposed workers. Genotoxicity parameters were associated with oxidative stress/inflammation biomarkers in urine and EBC, thus confirming that TiO2 exposure can affect the oxidative balance. Workers with higher genotoxic/oxidative stress biomarkers levels reported early respiratory symptoms suggesting that molecular alterations can be predictive of early health dysfunctions. These findings suggest the need to assess early health impairment in health surveillance programs and to address properly safety issues in workplaces where TiO2 is handled.

Biomarkers in exhaled breath condensate as fingerprints of asthma, chronic obstructive pulmonary disease and asthma-chronic obstructive pulmonary disease overlap: a critical review.

Asthma, chronic obstructive pulmonary disease (COPD) and asthma-COPD overlap are the third leading cause of mortality around the world. They share some common features, which can lead to misdiagnosis. To properly manage these conditions, reliable markers for early and accurate diagnosis are needed. Over the past 20years, many molecules have been investigated in the exhaled breath condensate to better understand inflammation pathways and mechanisms related to these disorders. Recently, more advanced techniques, such as sensitive metabolomic and proteomic profiling, have been used to obtain a more comprehensive understanding. This article reviews the use of targeted and untargeted metabolomic methodology to study asthma, COPD and asthma-COPD overlap.

Occupational exposure to nanomaterials and biomarkers in exhaled air and urine: Insights from the NanoExplore international cohort

The current evidence on nanomaterial toxicity is mostly derived from experimental studies making it challenging to translate it into human health risks. We established an international cohort (N = 141 workers) within the EU-LIFE project “NanoExplore” to address possible health effects from occupational exposures to nanomaterials. We used a handheld direct-reading optical particle counter to measure airborne nanoparticle number concentrations (PNC) and lung-deposited surface areas (LDSAs). Airborne particles were characterized by TEM and SEM-EDAX. We assessed oxidative/nitrosative stress with a panel of biomarkers in exhaled breath condensate (EBC) (8-isoprostane, malondialdehyde, nitrotyrosine), inflammation (high-sensitivity C reactive protein (hs-CRP), IL-1β, TNF-α, IL-10) and KL-6 (considered as biomarker of interstitial lung fibrosis) and urine (total antioxidant power (TAP), 8-isoprostane, and malondialdehyde). Exhaled breath sampled in gas-sampling bags were assessed for oxidative potential. These biomarkers were quantified pre-shift at the beginning of the workweek and post-shift the 4th day. Relationships between airborne nanoparticle concentration and biomarkers were assessed by multiple linear regression with log-transformed exposure and biomarker concentrations adjusted for potential confounders. We found a positive dose–response relationship for three inflammation biomarkers (IL-10, IL-1β and TNF-α) in EBC with both PNC and LDSA. A negative dose–response relationship was observed between PNC and TAP. This study suggests that occupational exposures to nanoparticles can affect the oxidative balance and the innate immunity in occupationally exposed workers. However, owing to the intrinsic variability of biomarkers, the observed changes along with their health significance should be assessed in a long-term perspective study.

Analysis of Inflammation Biomarkers in Exhaled Breath Condensate in Patients with COPD Combined with Peripheral Arterial Disease

Analysis of Inflammation Biomarkers in Exhaled Breath Condensate in Patients with COPD Combined with Peripheral Arterial Disease

Biomarkers of nitrosative stress in exhaled breath condensate and serum among patients with cystic fibrosis

PurposeThe measurement of biomarkers in exhaled breath condensate (EBC) offers a non-invasive way to assess airway disease and can be easily done in a clinical setting among patients with cystic fibrosis (CF). The role of oxidative and nitrosative stress in the complex pathophysiology of CF is widely accepted and biomarkers of oxidative and nitrosative stress can be measured in the serum and EBC. To our knowledge, this is the first study to assess markers of nitrosative stress in EBC and serum, collected simultaneously from the CF patients. Patients and methodsPaired EBC and serum samples were collected from 36 stable patients with CF and 14 healthy controls. Markers of nitrosative stress ‒ 3-nitrotyrosine and nitrate/nitrite were measured in the EBC and serum using an enzyme-linked immunosorbent assay. ResultsWe found no differences in 3-nitrotyrosine and nitrate/nitrite in the EBC of patients with CF as compared to healthy controls (125.37 ​± ​3.29 vs. 126.24 ​± ​2.21 ​nmol/L, p ​= ​0.218; 12.66 ​± ​7.23 vs. 8.79 ​± ​4.83 ​μmol/L, p ​= ​0.133, respectively). Furthermore, 3-nitrotyrosine and nitrate/nitrite were significantly higher in the serum of patients with CF as compared to the healthy controls (0.13 ​± ​0.02 vs. 0.11 ​± ​0.01 ​nmol/mg protein, p ​= ​0.003; 70.78 ​± ​22.55 vs. 53.08 ​± ​8.5 ​μmol/L, p ​= ​0.009, respectively). No correlations were found between the markers determined in the EBC and serum. ConclusionsThe results of the EBC nitrosative stress biomarkers should be interpreted with caution, especially in patients with stable disease, as the EBC values may be independent on levels of circulating markers that are elevated in the serum of patients with stable CF.

Oxidative Stress and Inflammatory Biomarkers for Populations with Occupational Exposure to Nanomaterials: A Systematic Review and Meta-Analysis.

Exposure to nanomaterials (NMs) is suggested to have the potential to cause harmful health effects. Activations of oxidative stress and inflammation are assumed as main contributors to NM-induced toxicity. Thus, oxidative stress- and inflammation-related indicators may serve as biomarkers for occupational risk assessment. However, the correlation between NM exposure and these biomarkers remains controversial. This study aimed to perform a meta-analysis to systematically investigate the alterations of various biomarkers after NM exposure. Twenty-eight studies were found eligible by searching PubMed, EMBASE and Cochrane Library databases. The pooled results showed NM exposure was significantly associated with increases in the levels of malonaldehyde (MDA) [standardized mean difference (SMD) = 2.18; 95% confidence interval (CI), 1.50-2.87], 4-hydroxy-2-nonhenal (HNE) (SMD = 2.05; 95% CI, 1.13-2.96), aldehydes C6-12 (SMD = 3.45; 95% CI, 2.80-4.10), 8-hydroxyguanine (8-OHG) (SMD = 2.98; 95% CI, 2.22-3.74), 5-hydroxymethyl uracil (5-OHMeU) (SMD = 1.90; 95% CI, 1.23-2.58), o-tyrosine (o-Tyr) (SMD = 1.81; 95% CI, 1.22-2.41), 3-nitrotyrosine (3-NOTyr) (SMD = 2.63; 95% CI, 1.74-3.52), interleukin (IL)-1β (SMD = 1.76; 95% CI, 0.87-2.66), tumor necrosis factor (TNF)-α (SMD = 1.52; 95% CI, 1.03-2.01), myeloperoxidase (MPO) (SMD = 0.25; 95% CI, 0.16-0.34) and fibrinogen (SMD = 0.11; 95% CI, 0.02-0.21), and decreases in the levels of glutathione peroxidase (GPx) (SMD = -0.31; 95% CI, -0.52--0.11) and IL-6 soluble receptor (IL-6sR) (SMD = -0.18; 95% CI, -0.28--0.09). Subgroup analysis indicated oxidative stress biomarkers (MDA, HNE, aldehydes C6-12, 8-OHG, 5-OHMeU, o-Tyr, 3-NOTyr and GPx) in exhaled breath condensate (EBC) and blood samples were strongly changed by NM exposure; inflammatory biomarkers (IL-1β, TNF-α, MPO, fibrinogen and IL-6sR) were all significant in EBC, blood, sputum and nasal lavage samples. In conclusion, our findings suggest that these oxidative stress and inflammatory indicators may be promising biomarkers for the biological monitoring of occupationally NM-exposed workers.

Exhaled breath condensate markers of oxidative stress in male storekeepers of chemical stores in the Ariaria international market Aba Abia state Nigeria.

In most developing countries, stores, where chemical substances are sold, are poorly ventilated, and best practices are not followed. This can result in the contamination of the ambient air inside the stores with toxicological implications for the lungs. This work aimed at determining the risk of pulmonary disease in chemical storekeepers in the Ariaria international market Aba by the evaluation of exhaled breath condensate (EBC) biomarkers of oxidative stress. A gas monitor was used for gas sampling while an Aerocet analyzer was used for particulate matter determinations. Exposed filter paper was used for the sampling of heavy metals in the air, and the determination was done using atomic absorption spectrophotometry. The exhaled breath condensate was collected with a refrigerated condenser, and the markers of oxidative stress were determined spectrophotometrically. Concentrations of particulate matter (PM1, PM2.5, PM4, PM7, PM10) were elevated in all the chemical stores studied. Our findings also showed that the indoor air of the chemical stores studied was polluted with SO2, NO2, NH3 and H2S, as their concentrations were respectively higher than the WHO standard values. Concentrations of all the heavy metals present in the ambient air of the chemical stores were also higher than the Nigerian Environmental Standard and Regulation Enforcement Agency (NESREA) standard values. Chemical storekeepers at the Ariaria international market exhaled increased concentrations of thiobarbituric acid reactive substances (TBARS), H2O2, and lower concentrations of glutathione (GSH). The pH values of the exhaled breath condensates were decreased and slightly acidic. It therefore means that the storekeepers were exposed to polluted ambient air inside the stores. This resulted to airway oxidative stress in the storekeepers as reported herein. Therefore, storekeepers of chemical stores in the Ariaria international market, Aba Nigeria were at risk of pulmonary disease(s).

Exposure to engineered nanomaterials and early biological effects measured in the exhaled breath condensate: First results from the NanoExplore cohort

BACKGROUND AND AIM Activities involving engineered nanomaterials (ENM) may raise concerns of occupational exposure and subsequent health effects. We aimed to build a multicenter prospective cohort to assess the potential effects of ENM exposure using biomarkers of early effects measured in exhaled breath condensate (EBC). METHODS We recruited seven centers in three countries (Switzerland, Spain, and Italy), where we conducted a 4-day exposure monitoring campaign and two EBC samplings, at the beginning (T1) and end (T2) of working week. The recruited workers were split in three groups depending on their exposure and compared in terms of their baseline individual and professional characteristics, and health status. EBC biomarkers of oxidative and nitrosative stress (malondialdehyde, 8-isoprostane, nitrotyrosine), systemic inflammation (High-Sensitivity C-Reactive Protein (hsCRP)), activation of pro-fibrotic cascade and interstitial lung disease (Krebs von den Lungen glycoprotein 6 (KL6)) and inflammatory cytokines (Interleukins (IL-10, IL-1β), Tumor necrosis factor (TNF-α)) were analyzed using multilevel mixed interval regression models. RESULTS The cohort included 140 participants: 43 non-exposed, 55 with negligible to low exposure, and 43 with medium to high exposure. The latter were gradually more often men, older, and in overweight than lowly exposed and non-exposed workers. A statistically significant change between T1 and T2 average concentrations was observed for malondialdehyde and KL6. Between-group differences were observed for all biomarkers but KL6 and nitrotyrosine. In multivariate models adjusted for age, sex and body mass index, a linear exposure-response relationship was observed for malondialdehyde, 8-isoprostane, IL-10, IL-1β, and TNF-α. ENM exposure was also associated with higher hs-CRP and KL6 levels, but not monotonically. CONCLUSION These first results suggest that ENM exposure might lead to early biological effects in workers’ airways. These findings need confirmation and a caution interpretation of their clinical significance, as most effects are non-specific and likely reversible.

Challenges in Quantifying 8-OHdG and 8-Isoprostane in Exhaled Breath Condensate.

Exhaled breath condensate (EBC) has attracted substantial interest in the last few years, enabling the assessment of airway inflammation with a non-invasive method. Concentrations of 8-Hydroxydesoxyguanosine (8-OHdG) and 8-isoprostane in EBC have been suggested as candidate biomarkers for lung diseases associated with inflammation and oxidative stress. EBC is a diluted biological matrix and consequently, requires highly sensitive chemical analytic methods (picomolar range) for biomarker quantification. We developed a new liquid chromatography coupled to tandem mass spectrometry method to quantify 8-OHdG and 8-isoprostane in EBC simultaneously. We applied this novel biomarker method in EBC obtained from 10 healthy subjects, 7 asthmatic subjects, and 9 subjects with chronic obstructive pulmonary disease. Both biomarkers were below the limit of detection (LOD) despite the good sensitivity of the chemical analytical method (LOD = 0.5 pg/mL for 8-OHdG; 1 pg/mL for 8-isoprostane). This lack of detection might result from factors affecting EBC collections. These findings are in line with methodological concerns already raised regarding the reliability of EBC collection for quantification of 8-OHdG and 8-isoprostane. Precaution is therefore needed when comparing literature results without considering methodological issues relative to EBC collection and analysis. Loss of analyte during EBC collection procedures still needs to be resolved before using these oxidative stress biomarkers in EBC.

Malondialdehyde and anion patterns in exhaled breath condensate among subway workers

BackgroundUnderground transportation systems can contribute to the daily particulates and metal exposures for both commuter and subway workers. The redox and metabolic changes in workers exposed to such metal-rich particles have yet to be characterized. We hypothesize that the distribution of nitrosative/oxidative stress and related metabolic biomarkers in exhaled breath condensate (EBC) are modified depending on exposures.ResultsParticulate number and size as well as mass concentration and airborne metal content were measured in three groups of nine subway workers (station agents, locomotive operators and security guards). In parallel, pre- and post-shift EBC was collected daily during two consecutive working weeks. In this biological matrix, malondialdehyde, lactate, acetate, propionate, butyrate, formate, pyruvate, the sum of nitrite and nitrate (ΣNOx) and the ratio nitrite/nitrate as well as metals and nanoparticle concentrations was determined. Weekly evolution of the log-transformed selected biomarkers as well as their association with exposure variables was investigated using linear mixed effects models with the participant ID as random effect. The professional activity had a strong influence on the pattern of anions and malondialdehyde in EBC. The daily number concentration and the lung deposited surface area of ultrafine particles was consistently and mainly associated with nitrogen oxides variations during the work-shift, with an inhibitory effect on the ΣNOx. We observed that the particulate matter (PM) mass was associated with a decreasing level of acetate, lactate and ΣNOx during the work-shift, suggestive of a build-up of these anions during the previous night in response to exposures from the previous day. Lactate was moderately and positively associated with some metals and with the sub-micrometer particle concentration in EBC.ConclusionsThese results are exploratory but suggest that exposure to subway PM could affect concentrations of nitrogen oxides as well as acetate and lactate in EBC of subway workers. The effect is modulated by the particle size and can correspond to the body’s cellular responses under oxidative stress to maintain the redox and/or metabolic homeostasis.

EBC-SURE (exhaled breath condensate- scanning using rapid electro analytics): A non-faradaic and non-invasive electrochemical assay to screen for pro-inflammatory biomarkers in human breath condensate

The innovation of this work lies in the trace detection of inflammatory biomarkers (IL-6, hs-CRP) in human exhaled breath condensate on the developed EBC-SURE platform as a point-of-care aid for respiratory disorder diagnosis. The unique design of the EBC-SURE leverages non-faradaic electrochemical impedance spectroscopy to capture target-specific biomolecular interactions for highly sensitive biomarker detection. For sensor calibration, EBC-SURE's performance is assessed to measure the response of the sensor to a known concentration by spike and recovery analysis with a recovery error of <20% and an extended dynamic range over 3-log orders. The lowest detection limits for IL-6 and hs-CRP detection in EBC were found to be 3.2 pg/mL and 4 pg/mL respectively. The intra-assay and inter-assay efficacy of EBC-SURE for its usage as a diagnostic device was established through repeatability and reproducibility (over 48 h s) performance testing. The percentage variations (<20%) met the Clinical and Laboratory Standards Institute standards (CLSI) indicating a highly stable performance for robust biomarker detection. EBC-SURE generated highly selective IL-6 and hs-CRP responses in the presence of other non-specific cytokines. Statistical validation methods- Correlation and Bland Altman analysis established the one-to-one agreement between EBC-SURE and the reference method. Correlation analysis generated a Pearson's R value of 0.99 for IL-6 and hs-CRP. Bland-Altman analysis indicated a good agreement between both the methods with all data points confined within the ±2SD limits. We have demonstrated EBC-SURE's ability in detecting inflammatory biomarkers in human breath condensate towards developing a non-invasive technology that can quantify biomarker levels associated with healthy and acute inflammatory conditions.

Inhaled corticosteroids’ effects on biomarkers in exhaled breath condensate and blood in patients newly diagnosed with asthma who smoke

Objective Exposure to cigarette smoke complicates the treatment and management of asthma through a variety of inflammatory effects. This study aimed to investigate the differences between newly diagnosed cases of asthma in smokers and nonsmokers in terms of localized and systemic biomarkers following treatment with inhaled corticosteroids (ICS) or ICS in combination with a long-acting β2 agonist (LABA). Methods Specimens of exhaled breath condensate (EBC) from newly diagnosed patients with asthma were used to quantify inflammation in the airways, while blood samples were used to assess systemic inflammation. In both samples, the levels of IL-6, LTB4, LTD4, and 8-isoprostane were measured and these were repeated after 3 months of treatment with ICS or ICS + LABA. Results Of the 20 patients, 10 (50%) were nonsmokers with asthma (NSA) and 10 (50%) smokers with asthma (SA). There was no statistically significant difference in the blood or EBC levels of IL-6, LTB4, LTD4, or 8-isoprostane between the groups prior to treatment. Only the decrease in 8-isoprostane level in the EBC samples was found to be significantly greater in the NSA group after treatment (for smokers, the change was 2.91 ± 23.22, while for nonsmokers it was −22.72 ± 33.12, p = 0.022). Post-treatment asthma control was significantly better in the NSA group (p = 0.033). Conclusion Monitoring the alterations in 8-isoprostane levels in EBC in patients with asthma who smoke may be helpful in deciding on therapeutic management and switching treatments. Asthma control was better in nonsmokers than in smokers.

Oxidative biomarkers of exhaled breath condensate in adults exposed to traffic-related air pollution: a case-control study

Traffic-related air pollution exposure (TRAP) is a major public health problem. The effects of TRAP exposure on the oxidative biomarkers of exhaled breath condensate (EBC) of adults are seldom studied. We compared the oxidative EBC biomarkers in a group of individuals exposed to TRAP with those of individuals unexposed to TRAP. We conducted a case-control study in Bhopal City (Madhya Pradesh, India). Adults with a history of exposure to TRAP were enrolled as cases and adults with less exposure to TRAP were used as a control. Based on respiratory symptoms and smoking habits, study subjects were stratified into six subgroups. EBC was collected by TURBO14 (Medivac SRL, Italy) at −5 °C. The EBC pH was measured after gas standardization with argon. EBC hydrogen peroxide (H2O2), cystenine leukotrienes (Cys-LTs), 8-isoprostane were measured by commercial ELISA kit. A total of 250 consecutive adult (male: 194) subjects were recruited. Among them, 133 were TRAP-exposed (male: 128) and 117 were non-TRAP-exposed (male: 66). The respiratory symptoms between TRAP-exposed and non-TRAP-exposed subjects were not different. The post-gas standardized EBC pH (median: 7.72; interquartile range (IQR): 7.15–7.94 vs. median: 7.60, IQR: 6.72–7.87; p = 0.09) and EBC H2O2 (median: 2.20 µmol l−1; IQR: 1.46–3.51 vs. median: 1.99, IQR: 1.41–3.10; p = 0.29) in TRAP-exposed subjects were statistically not different from the non-TRAP-exposed subjects. The EBC Cys-LTs (median: 69.81; IQR: 57.0–83.38 vs. median: 47.21 pg ml−1; IQR: 39.90–54.87, p < 0.001) and EBC 8-isoprostane (median: 12.55 pg ml−1; IQR: 5.51–18.09 vs. median: 7.12; IQR: 4.60–16.04, p = 0.026) in TRAP-exposed subjects were higher compared to those in non-TRAP-exposed subjects. The subgroup analysis showed that TRAP-exposed subjects, irrespective of their smoking habits and respiratory symptoms, had higher EBC Cys-LTs compared to the non-TRAP-exposed subjects. TRAP exposure increases oxidative biomarkers of the EBC in adults.

Investigating the relationship between particulate matter and inflammatory biomarkers of exhaled breath condensate and blood in healthy young adults

Inflammatory biomarkers in exhaled breath condensate (EBC) are measured to estimate the effects of air pollution on humans. The present study was conducted to investigate the relationship between particulate matter and inflammatory biomarkers in blood plasma and exhaled air in young adults. The obtained results were compared in two periods; i.e., winter and summer. GRIMM Dust Monitors were used to measure PM10, PM2.5, and PM1 in indoor and outdoor air. A total of 40 healthy young adults exhaling air condensate were collected. Then, biomarkers of interleukin-6 (IL-6), Nitrosothiols (RS-NOs), and Tumor necrosis factor-soluble receptor-II (sTNFRII) were measured by 96 wells method ELISA and commercial kits (HS600B R&D Kit and ALX-850–037-KI01) in EBC while interleukin-6 (IL-6), sTNFRII and White Blood Cell (WBC) were measured in blood plasma in two periods of February 2013 (winter) and May 2013 (summer). Significant association was found between particulate matter and the white blood cell count (p < 0.001), as well as plasma sTNFRII levels (p-value = 0.001). No significant relationship was found between particulate matter with RS-NOs (p = 0.128), EBC RSNOs (p-value = 0.128), and plasma IL-6 (p-value = 0.167). In addition, there was no significant relationship between interleukin-6 of exhaled air with interleukin-6 of plasma (p-value < 0.792 in the first period and < 0.890 in the second period). sTNFRII was not detected in EBC. Considering the direct effect between increasing some biomarkers in blood and EBC and particulate matter, it is concluded that air pollution causes this increasing.

Extracellular vesicle-derived microbiome obtained from exhaled breath condensate in patients with asthma

Extracellular vesicle-derived microbiome obtained from exhaled breath condensate in patients with asthma

Occupational exposure to graphene and silica nanoparticles. Part II: pilot study to identify a panel of sensitive biomarkers of genotoxic, oxidative and inflammatory effects on suitable biological matrices

The available biomonitoring studies on workers producing/handling nanomaterials (NMs) focused on potential effects on respiratory, immune and cardio-vascular system. Aim of this study was to identify a panel of sensitive biomarkers and suitable biological matrices to evaluate particularly genotoxic and oxidative effects induced on workers unintentionally exposed to graphene or silica nanoparticles during the production process. These nanomaterials have been chosen for ‘NanoKey’ project, integrating the workplace exposure assessment (reported in part I) with the biomonitoring of exposed workers reported in the present work. Simultaneously to workplace exposure characterization, we monitored the workers using: Buccal Micronucleus Cytome (BMCyt) assay, fpg-comet test (lymphocytes), oxidized DNA bases 8-oxoGua, 8-oxoGuo and 8-oxodGuo measurements (urine), analysis of oxidative stress biomarkers in exhaled breath condensate (EBC), FENO measurement and cytokines release detection (serum). Since buccal cells are among the main targets of NM occupational exposure, particular attention was posed to the BMCyt assay that represents a noninvasive assay. This pilot study, performed on 12 workers vs.11 controls, demonstrates that BMCyt and fpg-comet assays are the most sensitive biomarkers of early, still reparable, genotoxic and oxidative effects. The findings suggest that these biomarkers could represent useful tools for the biomonitoring of workers exposed to nanoparticles, but they need to be confirmed on a high number of subjects. However, such biomarkers don’t discriminate the effects of NM from those due to other chemicals used in the NM production process. Therefore, they could be suitable for the biomonitoring of workers exposed to complex scenario, including nanoparticles exposure.