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This report (D1.1) aims at creating a framework for the FIRE-RES project to facilitate a shared vision to tackle EWE. The first step starts by looking at the phenomena to address what needs to be faced with the innovation and resilience proposed in this project. Therefore, it is of paramount importance to address the process, mainly its behaviour and drivers (fuel in the ecosystem (t/ha), atmosphere, energy emission (kW/t), etc.). This deliverable includes the outputs of the initial workshops (WS) developed to create the project framework and the thematic lines that will guide the WP of the project (Task 1.1, WP1). These workshops took place at the beginning of the project and included the project pillars: (i) EWE process/behaviour drivers: fuel in the ecosystem (t/ha), atmosphere, energy emission (kW/t), to support WP5; (ii) emergency and fire management, to support WP2, WP4, WP5; (iii) landscape and economy, to support WP2-WP4; and (iv) governance, society, communication and risk awareness, to support WP4 and WP7.

Thrombospondins are a family of matricellular proteins with a multimeric structure that is known to be involved in several biological and pathological processes. Their relationship with vascular disorders has raised special interest recently. Aortic aneurysms are related to the impairment of vascular remodeling, in which extracellular matrix proteins seem to play an important role. Thus, research in thrombospondins, and their potential role in aneurysm development is progressively gaining importance. Nevertheless, studies showing thrombospondin dysregulation in human samples are still scarce. Although studies performed in vitro and in vivo models are essential to understand the molecular mechanisms and pathways underlying the disorder, descriptive studies in human samples are also necessary to ascertain their real value as biomarkers and/or novel therapeutic targets. The present article reviews the latest findings regarding the role of thrombospondins in aortic aneurysm development, paying particular attention to the studies performed in human samples.

Renal cell carcinoma (RCC) is the third most frequent urinary malignancy and one of the most lethal. Current diagnostic and follow-up techniques are harmful and unspecific in low-grade tumors. Novel minimally invasive markers such as urine microRNAs (miRNAs) are under study. However, discrepancies arise among studies in part due to lack of consent regarding normalization. We aimed to identify the best miRNA normalizer for RCC studies performed in urine samples together with a miRNA profile with diagnostic value and another for follow-up. We evaluated the performance of 120 candidate miRNAs in the urine of 16 RCC patients and 16 healthy controls by RT-qPCR followed by a stability analysis with RefFinder. In this screening stage, miR-20a-5p arose as the most stably expressed miRNA in RCC and controls, with a good expression level. Its stability was validated in an independent cohort of 51 RCC patients and 32 controls. Using miR-20a-5p as normalizer, we adjusted and validated a diagnostic model for RCC with three miRNAs (miR-200a-3p, miR-34a-5p and miR-365a-3p) (AUC = 0.65; Confidence Interval 95% [0.51, 0.79], p = 0.043). let-7d-5p and miR-205-5p were also upregulated in patients compared to controls. Comparing RCC samples before surgery and fourteen weeks after, we identified let-7d-5p, miR-152-3p, miR-30c-5p, miR-362-3p and miR-30e-3p as potential follow-up profile for RCC. We identified validated targets of most miRNAs in the renal cell carcinoma pathway. This is the first study that identifies a robust normalizer for urine RCC miRNA studies, miR-20a-5p, which may allow the comparison of future studies among laboratories. Once confirmed in a larger independent cohort, the miRNAs profiles identified may improve the non-invasive diagnosis and follow-up of RCC.

Simple Summary Bladder cancer (BC) is one of the most frequent cancers in the world and the urological tumor that presents the highest mortality. The diagnostic and prognostic methods available at present for BC are expensive and highly invasive for the patient, so the pursue of biomarkers that may replace those methods has been ongoing for years with limited success. One of these potential biomarkers is cell-free DNA, which can be found in liquid biopsies such as urine and blood. The present review summarizes the most recent research findings in the study of cell-free DNA to diagnose BC and even monitor treatment. Bladder cancer (BC) is among the most frequent cancer types in the world and is the most lethal urological malignancy. Presently, diagnostic and follow-up methods for BC are expensive and invasive. Thus, the identification of novel predictive biomarkers for diagnosis, progression, and prognosis of BC is of paramount importance. To date, several studies have evidenced that cell-free DNA (cfDNA) found in liquid biopsies such as blood and urine may play a role in the particular scenario of urologic tumors, and its analysis may improve BC diagnosis report about cancer progression or even evaluate the effectiveness of a specific treatment or anticipate whether a treatment would be useful for a specific patient depending on the tumor characteristics. In the present review, we have summarized the up-to-date studies evaluating the value of cfDNA as potential diagnostic, prognostic, or monitoring biomarker for BC in several biofluids.

Activated protein C (APC) acts as an "on demand" anticoagulant, reducing thrombin formation. Reduced plasma levels of APC or protein C (PC) are associated with an increased risk of venous thromboembolism. APC also displays cytoprotective functions and its therapeutic use has been evaluated in severe sepsis and is under evaluation in several diseases with an important inflammatory component. In addition, different studies have revealed a potential role of PC/APC in disorders such as obesity, pneumonia, disseminated intravascular coagulation, Alzheimer, stroke, etc. Accordingly, the therapeutic value of different recombinant APC molecules that lack anticoagulant activity but retain the cytoprotective function is being tested in clinical trials for some of these diseases. Therefore, an available method to measure circulating APC in plasma is of great interests. About 16 different methods for the quantification of APC have been reported. Here, we will review the available assays, highlighting their advantages and disadvantages as well as their different stages of implementation and the most appropriate use for each method, including their potential clinical usefulness.

Abdominal aortic aneurysm (AAA) is a vascular disorder caused by a dilatation of the aortic diameter that can be potentially lethal in case of rupture. Molecular mechanisms underlying the development of AAA are complex and not completely understood. However, inflammation plays a pivotal role in AAA development. Infiltration of inflammatory cells, especially macrophages, has been widely observed in lesion areas. Nevertheless, neutrophils have been gaining importance in the context of AAA. The release of neutrophil extracellular traps (NETs), extracellular structures formed by DNA, histones, granular and cytoplasmic proteins, is a recently discovered mechanism of neutrophil activation that can be triggered by endogenous inflammatory stimulus. The number of studies about the role of NETs in several vascular diseases like thrombosis and atherosclerosis has increased in last decade. However, its role in AAA has been scarcely analysed. The aim of this review is to deepen in the latest advances concerning the potential role neutrophils and especially NETs in AAA development.

Upon activation, neutrophils release their content through different mechanisms like degranulation and NETosis, thus prompting thrombosis. The natural anticoagulant activated protein C (APC) inhibits neutrophil NETosis and, consequently, this may lower the levels of neutrophil activation markers in plasma, further diminishing the thrombotic risk exerted by this anticoagulant. We aimed to describe the status of markers of neutrophil activation in plasma of patients with venous thrombosis, their association with the thrombotic risk and the potential contribution of APC. We quantified three markers of neutrophil activation (cell-free DNA, calprotectin, and myeloperoxidase) in 253 patients with venous thromboembolism (VTE) in a stable phase (192 lower extremity VTE and 61 splanchnic vein thrombosis) and in 249 healthy controls. In them, we also quantified plasma APC, soluble endothelial protein C receptor (EPCR), and soluble thrombomodulin (TM), and we genotyped two genetic regulators of APC: the EPCR gene (PROCR) haplotypes (H) and the TM gene (THBD) c.1418C>T polymorphism. We found a significant increase in plasma cell-free DNA (p< 0.0001), calprotectin (p= 0.0001) and myeloperoxidase (p= 0.005) in VTE patients compared to controls. Furthermore, all three neutrophil activation markers were associated with an increase in the thrombotic risk. Cell-free DNA and calprotectin plasma levels were significantly correlated (Spearmanr= 0.28;p< 0.0001). As expected, the natural anticoagulant APC was significantly decreased in VTE patients (p< 0.0001) compared to controls, what was mediated by its genetic regulatorsPROCR-H1,PROCR-H3, andTHBD-c.1418T, and inversely correlated with cell-free DNA levels. This is the largest case-control study that demonstrates the increase in markers of neutrophil activation in vivo in VTE patients and their association with an increased thrombotic risk. This increase could be mediated by low APC levels and its genetic regulators, which could also increase NETosis, further enhancing thrombosis and inflammation.

Renal cell carcinoma (RCC) is one of the most lethal type of tumors and is twice more frequent in men than in women. Initial symptoms are unspecific and belated thus increasing mortality. Moreover, current diagnostic and monitoring tools are harmful for the patient and unspecific in low-grade tumors. Therefore, novel minimally-invasive markers are needed to diagnose and monitor RCC patients. Urine represents the ideal sample source of non-invasive biomarkers for RCC. In our study we aimed to identify a urine metabolomic profile characteristic of RCC patients with diagnostic purposes and also to identify a profile with prognostic value. By an UPLC-Q-ToF MS untargeted metabolomic analysis, we compared the metabolomic profile of 23 RCC patients (14 clear cell RCC and 9 papillary RCC) before surgery and that of 23 healthy controls. Additionally, for the first time, we compared the metabolomic profile of these RCC patients pre-nephrectomy and 3 months and one year post-nephrectomy. We identified the dysregulated metabolomic variables by querying their exact mass against those presented in the Metlin and Human Metabolome Database. Next, we experimentally confirmed their identity. Both RCC subtypes showed similar metabolomic patterns at all stages. 51 metabolomic variables were significantly increased in RCC compared to controls and, among them, 4 were selected as potential discriminant metabolites between groups. We could experimentally confirm the identity of p-cresol glucuronide thus describing for the first time an increase in this metabolite in urine of RCC patients (fold change = 2.922, P=.012). Additionally, we confirmed that no metabolomic differences occur 3 months post-nephrectomy in RRC, while 188 variables were significantly increased one year post-nephrectomy. Of the 15 most discriminant metabolomic variables, we could experimentally confirm the identity of isobutyryl-L-carnitine (fold change = 2.098, P=.004) and L-proline betaine (fold change = 3.328, P=.004), for the first time. In summary, we have identified urine p-cresol glucuronide as potential diagnostic marker for RCC and isobutyryl-L-carnitine and L-proline betaine as potential prognostic markers. When confirmed in an independent cohort of RCC patients, these markers may improve the diagnosis and monitoring of RCC patients thus reducing current harmful diagnostic procedures. Significance: The high-radiation dose of current imaging techniques available to diagnose and monitor renal cell carcinoma (RCC) are harmful for the patient and unspecific in low-grade tumors. Our untargeted metabolomic analysis carried out in urine samples from RCC patients and healthy individual reveals p-cresol glucuronide as potential diagnostic marker for RCC. Additionally, the analysis of RCC urine samples one year post-nephrectomy reveals isobutyryl-L-carnitine and L-proline betaine as potential prognostic markers. These novel non-invasive urine biomarkers may improve RCC management thus reducing the use of current harmful diagnostic techniques.

Presently, no data on the molecular basis of hereditary protein C (PC) deficiency in Spain is available. We analyzed the PC gene ( PROC ) in 109 patients with symptomatic PC deficiency and in 342 relatives by sequencing the 9 PROC exons and their flanking intron regions. In 93 probands, we found 58 different mutations (26 novel). Thirty-seven consisted of a nucleotide change, mainly missense mutations, 1 was a 6-nucleotide insertion causing the duplication of 2 amino acids, and 4 were deletions of 1, 3, 4, and 16 nucleotides. Nine mutations caused type II deficiencies, with the presence of normal antigen levels but reduced anticoagulant activity. Using a PC level of 70% as lowest normal limit, we found no mutations in 16 probands and 25 relatives with PC levels 70% carried the mutation identified in the proband. The spectrum of recurrent mutations in Spain is different from that found in the Netherlands, where the most frequent mutations were p.Gln174* and p.Arg272Cys, and is more similar to that found in France, where the most frequent were p.Arg220Gln and p.Pro210Leu. In our study, p.Val339Met (9 families), p.Tyr166Cys (7), p.Arg220Gln (6), and p.Glu58Lys (5) were the most prevalent. This study confirms the considerable heterogeneity of the genetic abnormality in PC deficiencies, and allowed genetic counseling to those individuals whose PC levels were close to the lower limit of the normal reference range.

Introduction: MicroRNAs (miRs) are small RNA molecules that are involved in several biological processes. Due to their stability and their presence in biological fluids, several studies over the last few years have focused on the use of miRs as biomarkers of different pathologies. Objective: Selection of a group of miRs candidates to be validated as potential biomarkers ofabdominal aortic aneurysm (AAA). Material and methods: A total of 179 miRs were quantified in 7 patients with AAA and in 7 healthy donors, using predesigned panels based on RT-qPCR technology. Results: A total of 10 miRs, dysregulated in patients, were selected as good candidates for studying them as biomarkers. It has been observed that most of these miRs participate in several biological processes related to the formation and development of AAAs. Conclusion: Additional, as well as validation, studies are needed, but some of these miRs could be non-invasive AAA biomarkers. (c) 2017 SEACV. Published by Elsevier Espana, S.L.U. All rights reserved.

Purpose: Results from observational studies on inhaled long-acting beta-2-agonists (LABA) and acute myocardial infarction (AMI) risk are conflicting, presumably due to variation in methodology. We aimed to evaluate the impact of applying a common study protocol on consistency of results in three databases. Methods: In the primary analysis, we included patients from two GP databases (Dutch—Mondriaan, UK—CPRD GOLD) with a diagnosis of asthma and/or COPD and at least one inhaled LABA or a “non-LABA inhaled bronchodilator medication” (short-acting beta-2-agonist or short-/long-acting muscarinic antagonist) prescription between 2002 and 2009. A claims database (USA—Clinformatics) was used for replication. LABA use was divided into current, recent (first 91 days following the end of a treatment episode), and past use (after more than 91 days following the end of a treatment episode). Adjusted hazard ratios (AMI-aHR) and 95 % confidence intervals (95 % CI) were estimated using time-dependent multivariable Cox regression models stratified by recorded diagnoses (asthma, COPD, or both asthma and COPD). Results: For asthma or COPD patients, no statistically significant AMI-aHRs (age- and sex-adjusted) were found in the primary analysis. For patients with both diagnoses, a decreased AMI-aHR was found for current vs. recent LABA use in the CPRD GOLD (0.78; 95 % CI 0.68–0.90) and in Mondriaan (0.55; 95 % CI 0.28–1.08), too. The replication study yielded similar results. Adjusting for concomitant medication use and comorbidities, in addition to age and sex, had little impact on the results. Conclusions: By using a common protocol, we observed similar results in the primary analysis performed in two GP databases and in the replication study in a claims database. Regarding differences between databases, a common protocol facilitates interpreting results due to minimized methodological variations. However, results of multinational comparative observational studies might be affected by bias not fully addressed by a common protocol.

Background: For patients with asthma, COPD, or asthma-COPD overlap syndrome (ACOS), inter-country comparisons of seasonal changes in drug prescriptions are scarce or missing. Hence, we aimed to compare seasonal changes in prescription rates of long-acting beta-2-agonist (LABA) in four European countries. Methods: A common study protocol was applied to six health care databases (Germany, Spain, the Netherlands (2), and the UK (2)) to calculate age- and sex-standardized point prevalence rates (PPRs) of LABA-containing prescriptions by the 1st of March, June, September, and December of each year during the study period 2002e2009. Seasonal variation of PPRs was quantified using seasonal indexes (SIs; based on the ratio-to-moving-average-method) and SIs averaged over the study period (aSI) stratified by sex, age, and indication (asthma, COPD, or ACOS). Results: There was a moderate seasonal change in LABA-containing prescriptions which was more pronounced in asthma or COPD patients compared to ACOS patients. For asthma and ACOS patients, highest seasonal variation was found for patients living in Spain (aSI: 87.3e110.7, aSI: 93.2e103.1) whereas for COPD highest seasonal variation was revealed for the NPCRD database (the Netherlands) (aSI: 92.2e105.6). Regarding age and sex, highest seasonal variation was found in Spanish boys under 10 years of age having a diagnosis of asthma. Conclusions: By applying a common analysis in six databases, we could observe moderate overall seasonal changes in LABA-containing prescription rates in patients with asthma, COPD, or ACOS.

Background: Asthma and allergy might influence the choice of keeping pets, leading to apparent protective effects of pets on allergic disease. Objective: We investigated the effects of asthma and allergy on subsequent pet keeping in childhood and adulthood. Methods: Information about asthma and pet keeping at ages 0 to 4, 5 to 15, 20 to 44, and 26 to 56 years was provided by 9812 subjects participating in the 9-year follow-up of the European Community Respiratory Health Survey. Results: In childhood asthma debut at younger than 5 years was associated with less cat keeping at 5 to 15 years (odds ratio [OR], 0.60; 95% CI, 0.44-0.82), an effect only observed when the parents did not have asthma or allergy (P interaction = .045). Childhood asthma did not influence adult pet ownership, unless there were adult symptoms. Adults less often acquired cats at follow-up if they had 3 or more asthma symptoms (OR, 0.78; 95% CI, 0.64-0.95), were taking asthma medication (OR, 0.48; 95% CI, 0.31-0.74), had hay fever (OR, 0.75; 95% CI, 0.62-0.91), had atopy (OR, 0.75; 95% CI, 0.61-0.91), or had specific IgE to cat (OR, 0.57; 95% CI, 0.39-0.82) at baseline. Adults who already had pets usually continued keeping the same type of pet, except that the presence of 3 or more asthma symptoms was associated with less subsequent dog keeping (OR, 0.69; 95% CI, 0.53-0.89). Pet removal between surveys to reduce allergen was reported by 4.7%. Conclusion: Selective avoidance subsequent to asthma or allergy was observed for childhood cat keeping and adult cat acquisition. Avoidance would produce an apparent protective effect of cats on childhood asthma (large OR, 0.83). Avoidance was generally not observed for dogs or birds. Clinical implications: A part of the protective effects of childhood cats on asthma and allergy can be attributed to selective avoidance. © 2006 American Academy of Allergy, Asthma and Immunology.

Tetraconazole is currently used as a fungicide in fruit and vegetables. The aim of this work was the development of immunochemical techniques based on recombinant antibodies for the screening of tetraconazole residues in fruit juices. Recombinant antibodies were produced from a hybridoma cell line secreting a monoclonal antibody specific for tetraconazole and from lymphocytes of mice hyperimmunised with tetraconazole haptens conjugated to bovine serum albumin. From these antibodies, enzyme-linked immunosorbent assays in the conjugate-coated format were developed, which were able to detect tetraconazole standards down to 1 ng/mL. From recovery studies with spiked samples, these immunoassays determined tetraconazole in orange and apple juices with acceptable reproducibility (coefficients of variation below 25%) and recoveries (ranging from 78% to 145%) for a screening technique. The analytical performance of RAb-based immunoassays was fairly similar to that of the MAb-based immunoassays. Due to their simplicity and high sample throughput, the developed recombinant-based immunoassays can be valuable analytical tools for the screening of tetraconazole residues in fruit juices at regulatory levels. (C) 2013 Elsevier Ltd. All rights reserved.

The goal of this study was to identify occupational risk factors for severe exacerbation of asthma and estimate the extent to which occupation contributes to these events. The 966 participants were working adults with current asthma who participated in the follow-up phase of the European Community Respiratory Health Survey. Severe exacerbation of asthma was defined as self-reported unplanned care for asthma in the past 12 months. Occupations held in the same period were combined with a general population job-exposure matrix to assess occupational exposures. 74 participants reported having had at least one severe exacerbation event, for a 1-yr cumulative incidence of 7.7%. From regression models that controlled for confounders, the relative risk (RR) was statistically significant for low (RR 1.7, 95% CI 1.1-2.6) and high (RR 3.6, 95% CI 2.2-5.8) biological dust exposure, high mineral dust exposure (RR 1.8, 95% CI 1.02-3.2), and high gas and fumes exposure (RR 2.5, 95% CI 1.2-5.5). The summary category of high dust, gas, or fumes exposure had RR 3.1 (95% CI 1.9-5.1). Based on this RR, the population attributable risk was 14.7% among workers with current asthma. These results suggest occupation contributes to approximately one in seven cases of severe exacerbation of asthma in a working population, and various agents play a role.

Background: Previous cross-sectional studies have shown that job change due to breathing problems at the workplace (respiratory work disability) is common among adults of working age. That research indicated that occupational exposure to gases, dust and fumes was associated with job change due to breathing problems, although causal inferences have been tempered by the cross-sectional nature of previously available data. There is a need for general population-based prospective studies to assess the incidence of respiratory work disability and to delineate better the roles of potential predictors of respiratory work disability. Methods: A prospective general population cohort study was performed in 25 centres in 11 European countries and one centre in the USA. A longitudinal analysis was undertaken of the European Community Respiratory Health Survey including all participants employed at any point since the baseline survey, 6659 subjects randomly sampled and 779 subjects comprising all subjects reporting physician-diagnosed asthma. The main outcome measure was new-onset respiratory work disability, defined as a reported job change during follow-up attributed to breathing problems. Exposure to dusts (biological or mineral), gases or fumes during follow-up was recorded using a job-exposure matrix. Cox proportional hazard regression modelling was used to analyse such exposure as a predictor of time until job change due to breathing problems. Results: The incidence rate of respiratory work disability was 1.2/1000 person-years of observation in the random sample (95% CI 1.0 to 1.5) and 5.7/1000 person-years in the asthma cohort (95% CI 4.1 to 7.8). In the random population sample, as well as in the asthma cohort, high occupational exposure to biological dust, mineral dust or gases or fumes predicted increased risk of respiratory work disability. In the random sample, sex was not associated with increased risk of work disability while, in the asthma cohort, female sex was associated with an increased disability risk (hazard ratio 2.8, 95% CI 1.3 to 5.9). Conclusions: Respiratory work disability is common overall. It is associated with workplace exposures that could be controlled through preventive measures.

Background: Smoking is associated with a systemic inflammatory response. However, the role of genetic predisposition is well known. We assessed whether circulatory acute phase reactants were associated with smoking and whether or not the association was modified by the major cytokine gene of the phase reaction, interleukin-6 (IL-6). Methods: in total, 1,003 postmyocardial infarction patients were recruited in six European cities and six repeated clinical examinations performed. C-reactive protein (CRP), interleukin 6 (IL-6), and fibrinogen, levels were assayed at 5,659 subject visits. Genotyping of single nucleotide polymorphisms was performed in the IL-6 gene. Results: Cumulative smoking (pack-years) and time since smoking cessation were strongly associated with blood levels of all three inflammatory markers. Among subjects any respiratory disorder, these associations remained statistically significant for CRP and IL-6. A polymorphism in the IL-6 gene (rs2069840) showed an interaction with on CRP (p < .001) and IL-6 (p = .049) peripheral levels. Conclusions: These results indicate a potential role of the IL-6 gene in the inflammatory response associated with smoking and suggest rs2069840 polymorphism deserves attention.

BACKGROUND: Previous cross-sectional studies have shown that job change due to breathing problems at the workplace (respiratory work disability) is common among adults of working age. That research indicated that occupational exposure to gases, dust and fumes was associated with job change due to breathing problems, although causal inferences have been tempered by the cross-sectional nature of previously available data. There is a need for general population-based prospective studies to assess the incidence of respiratory work disability and to delineate better the roles of potential predictors of respiratory work disability. METHODS: A prospective general population cohort study was performed in 25 centres in 11 European countries and one centre in the USA. A longitudinal analysis was undertaken of the European Community Respiratory Health Survey including all participants employed at any point since the baseline survey, 6659 subjects randomly sampled and 779 subjects comprising all subjects reporting physician-diagnosed asthma. The main outcome measure was new-onset respiratory work disability, defined as a reported job change during follow-up attributed to breathing problems. Exposure to dusts (biological or mineral), gases or fumes during follow-up was recorded using a job-exposure matrix. Cox proportional hazard regression modelling was used to analyse such exposure as a predictor of time until job change due to breathing problems. RESULTS: The incidence rate of respiratory work disability was 1.2/1000 person-years of observation in the random sample (95% CI 1.0 to 1.5) and 5.7/1000 person-years in the asthma cohort (95% CI 4.1 to 7.8). In the random population sample, as well as in the asthma cohort, high occupational exposure to biological dust, mineral dust or gases or fumes predicted increased risk of respiratory work disability. In the random sample, sex was not associated with increased risk of work disability while, in the asthma cohort, female sex was associated with an increased disability risk (hazard ratio 2.8, 95% CI 1.3 to 5.9). CONCLUSIONS: Respiratory work disability is common overall. It is associated with workplace exposures that could be controlled through preventive measures.

Background: Professional use of hypochlorite (bleach) has been associated with respiratory symptoms. Bleach is capable of inactivating allergens, and there are indications that its domestic use may reduce the risk of allergies in children. Objective: To study the associations between household use of bleach and atopic sensitization, allergic diseases, and respiratory health status in adults. Methods: We identified 3626 participants of the European Community Respiratory Health Survey 11 in 10 countries who did the cleaning in their homes and for whom data on specific serum IgE to 4 environmental allergens were available. Frequency of bleach use and information on respiratory symptoms were obtained in face-to-face interviews. House dust mite and cat allergens in mattress dust were measured in a subsample. Associations between the frequency of bleach use and health outcomes were evaluated by using multivariable mixed logistic regression analyses. Results: The use of bleach was associated with less atopic sensitization (odds ratio [OR], 0.75; 95% CI, 0.63-0.89). This association was apparent for specific IgE to both indoor (cat) and outdoor (grass) allergens, and was consistent in various subgroups, including those without any history of respiratory problems (OR, 0.85). Dose-response relationships (P