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BackgroundNight shift work can disrupt circadian rhythm and cause chronic sleep deprivation, which might increase the risk of lymphoma through immunosuppression and oxidative stress.Material and methodsWe investigated the association between night shift work and risk of lymphoma subtypes in 867 incident cases and 774 controls, who participated in a multicentre Italian study between 2011 and 2017. Based on questionnaire information, occupational experts assessed the lifetime probability of night shift work, the total number of night shifts and years of night shift work among study participants. OR and 95% CI for lymphoma and its major subtypes associated with night shift work was calculated with logistic regression, adjusting by age, gender, education, study area, marital status and family history of haemolymphatic cancer.ResultsEver working night shifts was associated with an increase in the risk of chronic lymphocytic leukaemia (CLL) (OR 1.9, 95% CI 1.14 to 3.32), which was highest after a 15–34 years latency. However, there was not a linear increase in risk by probability of exposure, years of night shift work, nor lifetime number of night shifts whether under rotating or permanent work schedules. Risk of lymphoma overall, B cell lymphoma (BCL), its major subtypes other than CLL, and other less prevalent BCL subtypes combined did not show an association.ConclusionsWe found conflicting evidence of an association between night shift work and the risk of CLL. We did not observe an association with other lymphoma subtypes.

The increasing use of nanomaterials in a variety of industrial, commercial, medical products, and their environmental spreading has raised concerns regarding their potential toxicity on human health. Titanium dioxide nanoparticles (TiO2 NPs) represent one of the most commonly used nanoparticles. Emerging evidence suggested that exposure to TiO2 NPs induced reproductive toxicity in male animals. In this in vitro study, porcine prepubertal Sertoli cells (SCs) have undergone acute (24 h) and chronic (from 1 up to 3 weeks) exposures at both subtoxic (5 µg/ml) and toxic (100 µg/ml) doses of TiO2 NPs. After performing synthesis and characterization of nanoparticles, we focused on SCs morphological/ultrastructural analysis, apoptosis, and functionality (AMH, inhibin B), ROS production and oxidative DNA damage, gene expression of antioxidant enzymes, proinflammatory/immunomodulatory cytokines, and MAPK kinase signaling pathway. We found that 5 µg/ml TiO2 NPs did not induce substantial morphological changes overtime, but ultrastructural alterations appeared at the third week. Conversely, SCs exposed to 100 µg/ml TiO2 NPs throughout the whole experiment showed morphological and ultrastructural modifications. TiO2 NPs exposure, at each concentration, induced the activation of caspase-3 at the first and second week. AMH and inhibin B gene expression significantly decreased up to the third week at both concentrations of nanoparticles. The toxic dose of TiO2 NPs induced a marked increase of intracellular ROS and DNA damage at all exposure times. At both concentrations, the increased gene expression of antioxidant enzymes such as SOD and HO-1 was observed whereas, at the toxic dose, a clear proinflammatory stress was evaluated along with the steady increase in the gene expression of IL-1α and IL-6. At both concentrations, an increased phosphorylation ratio of p-ERK1/2 was observed up to the second week followed by the increased phosphorylation ratio of p-NF-kB in the chronic exposure. Although in vitro, this pilot study highlights the adverse effects even of subtoxic dose of TiO2 NPs on porcine prepubertal SCs functionality and viability and, more importantly, set the basis for further in vivo studies, especially in chronic exposure at subtoxic dose of TiO2 NPs, a condition closer to the human exposure to this nanoagent.

Background The International Agency for Research on Cancer (IARC) recently classified glyphosate, the most used herbicide worldwide, as a probable human carcinogen. We inquired into the association between occupational exposure to glyphosate and risk of lymphoma subtypes in a multicenter case-control study conducted in Italy. Methods The Italian Gene-Environment Interactions in Lymphoma Etiology (ItGxE) study took place in 2011–17 in six Italian centres. Overall, 867 incident lymphoma cases and 774 controls participated in the study. Based on detailed questionnaire information, occupational experts classified duration, confidence, frequency, and intensity of exposure to glyphosate for each study subject. Using unconditional regression analysis, we modelled risk of major lymphoma subtypes associated with exposure to glyphosate adjusted by age, gender, education, and study centre. Results Very few study subjects (2.2%) were classified as ever exposed to glyphosate. Risk of follicular lymphoma (FL) was elevated 7-fold in subjects classified as ever exposed to glyphosate with medium-high confidence, 4.5-fold in association with medium-high cumulative exposure level, 12-fold with medium-high exposure intensity, and 6-fold with exposure for 10 days or more per year. Significant upward trends were detected with all the exposure metrics, but duration. The overall p-value for an upward trend with four independent metrics was 1.88 × 10− 4. There was no association with risk of lymphoma (any subtype), Non Hodgkin Lymphoma, B-cell lymphoma, or the major lymphoma subtypes other than FL. Conclusions Our findings provide limited support to the IARC decision to classify glyphosate as Group 2A human carcinogen.

BackgroundThe International Agency for Research on Cancer (IARC) recently classified glyphosate, the most used herbicide worldwide, as a probable human carcinogen. We inquired into the association between occupational exposure to glyphosate and risk of lymphoma subtypes in a multicenter case-control study conducted in Italy. MethodsThe Italian Gene-Environment Interactions in Lymphoma Etiology (ItGxE) study took place in 2011-17 in six Italian centres. Overall, 867 incident lymphoma cases and 774 controls participated in the study. Based on detailed questionnaire information, occupational experts classified duration, confidence, frequency, and intensity of exposure to glyphosate for each study subject. Using unconditional regression analysis, we modelled risk of major lymphoma subtypes associated with exposure to glyphosate adjusted by age, gender, education, and study centre. ResultsVery few study subjects (2.2%) were classified as ever exposed to glyphosate. Risk of follicular lymphoma (FL) was elevated 7-fold in subjects classified as ever exposed to glyphosate with medium-high confidence, 4.5-fold in association with medium-high cumulative exposure level, 12-fold with medium-high exposure intensity, and 6-fold with exposure for 10 days or more per year. Significant upward trends were detected with all the exposure metrics, but duration. The overall p-value for an upward trend with four independent metrics was 1.88 x 10-4. There was no association with risk of lymphoma (any subtype), Non Hodgkin Lymphoma, B-cell lymphoma, or the major lymphoma subtypes other than FL. ConclusionsOur findings provide limited support to the IARC decision to classify glyphosate as Group 2A human carcinogen.

The area of Civitavecchia (Lazio region, Central Italy) has been a reason of concern in the past because of environmental air contamination. The aim of this study was to evaluate the association between air pollution from different sources and respiratory symptoms and lung function in the population. A sample of 1177 residents underwent medical examination and lung function tests. Information on individual characteristics, histories of exposure and medical history were collected through a validated questionnaire. Long-term exposure to industrial, harbour, biomass combustion emissions (PM10) and urban traffic (NOx) at residential address was assessed using a Lagrangian dispersion model. The associations between exposure and wheezing and dyspnea were assessed using logistic regression models, while modified Poisson regression models were used to evaluate cough with phlegm. Relationships between exposure and lung function were analysed using linear mixed-effects models and cross-correlation. PM10 emissions from the harbour were associated with lower lung function parameters (FEV1: &beta, = &ndash, 0.12, 95% CI &ndash, 0.21 &ndash, 0.03, p = 0.02, FEV1/FVC: &beta, 1.67, (&ndash, 3.10 &ndash, 0.23), p = 0.02. This association was observed also in healthy subjects, but not in females. We found, even if at low exposure level, an effect of environmental PM10 exposure from harbour on lung function.

Oxidative stress is considered to be a key factor of the pathogenesis of Parkinson&rsquo, s disease, a multifactorial neurodegenerative disorder characterized by reduced dopaminergic neurons in the substantia nigra pars compacta and accumulated protein aggregates. Rotenone is a worldwide-used pesticide that induces the most common features of Parkinson&rsquo, s by direct inhibition of the mitochondrial complex I. Rotenone-induced Parkinson&rsquo, s models, as well as brain tissues from Parkinson&rsquo, s patients, are characterized by the presence of both lipid peroxidation and protein oxidation markers resulting from the increased level of free radical species. Oxidation introduces several modifications in protein structure, including carbonylation and nitrotyrosine formation, which severely compromise cell function. Due to the link existing between oxidative stress and Parkinson&rsquo, s disease, antioxidant molecules could represent possible therapeutic tools for this disease. In this study, we evaluated the effect of curcumin, a natural compound known for its antioxidant properties, in dopaminergic PC12 cells treated with rotenone, a cell model of Parkinsonism. Our results demonstrate that the treatment of PC12 cells with rotenone causes severe protein damage, with formation of both carbonylated and nitrotyrosine-derived proteins, whereas curcumin (10 &micro, M) co-exposure exerts protective effects by reducing the levels of oxidized proteins. Curcumin also promotes proteasome activation, abolishing the inhibitory effect exerted by rotenone on this degradative system.

The term “united airway disease” has been used since 2000 to describe the strong association between asthma and rhinitis. Although this term is not extensively used, it refers to the fact that asthma and rhinitis are frequently associated and share common risk factors, causal agents and mechanisms. Similarly, since 2010 the term occupational united airway disease has been used to describe the strong association between occupational asthma and rhinitis. Rhinitis and occupational rhinitis are less severe diseases but more frequent than asthma and occupational asthma, respectively. Every year several case reports and epidemiological studies enhance the long list of agents responsible for occupational asthma and rhinitis with new agents or occupations. Primary, secondary and tertiary prevention strategies are aimed at reduction of the onset and severity of work-related respiratory diseases. Primary prevention mainly includes avoiding/reducing exposure to known sensitizing/irritant agents. Secondary prevention or early detection should focus on medical surveillance of individuals at risk, health and safety education and training of workers, and recognition of early bronchial/nasal symptoms. Tertiary prevention includes early recognition and diagnosis, appropriate removal from further exposure and pharmacologic treatment. Unfortunately, pharmacologic treatment has seldom been studied in occupational asthma and rhinitis, and it usually refers to the international guidelines of management of asthma and rhinitis aimed to achieve control of the two diseases. For simultaneous treatment of asthma and rhinitis, the anti-IgE monoclonal antibody omalizumab, effective in occupational asthma and rhinitis, is available. Immunotherapy has been shown to be effective in health care workers with occupational asthma due to natural rubber latex, in workers with occupational asthma due to laboratory animals and in baker’s asthma. A limitation of immunotherapy, however, can be systemic reactions after subcutaneous injections of sometimes non-standardized and non-purified extracts.

International audience; Epidemiologic studies show an increased risk of non-Hodgkin lymphoma (NHL) in patients with autoimmune disease (AD), due to a combination of shared environmental factors and/or genetic factors, or a causative cascade: chronic inflammation/antigen-stimulation in one disease leads to another. Here we assess shared genetic risk in genome-wide-association-studies (GWAS). Secondary analysis of GWAS of NHL subtypes (chronic lymphocytic leukemia, diffuse large B-cell lymphoma, follicular lymphoma, and marginal zone lymphoma) and ADs (rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis). Shared genetic risk was assessed by (a) description of regional genetic of overlap, (b) polygenic risk score (PRS), (c)"diseasome", (d)meta-analysis. Descriptive analysis revealed few shared genetic factors between each AD and each NHL subtype. The PRS of ADs were not increased in NHL patients (nor vice versa). In the diseasome, NHLs shared more genetic etiology with ADs than solid cancers (p = .0041). A meta-analysis (combing AD with NHL) implicated genes of apoptosis and telomere length. This GWAS-based analysis four NHL subtypes and three ADs revealed few weakly-associated shared loci, explaining little total risk. This suggests common genetic variation, as assessed by GWAS in these sample sizes, may not be the primary explanation for the link between these ADs and NHLs.

Smoke components, such as nicotine and its major metabolites, cross the blood-testis barrier and are detectable in the seminal plasma of both active smokers and individuals exposed to cigarette smoke. In vivo studies in a rat model have further demonstrated that nicotine exposure reduces the weight of the testis, as well as the number of spermatocytes and spermatids, and affects the ultrastructure of Sertoli cells (SC) - which serve as sentinels of spermatogenesis - causing intense germ cell sloughing in the tubular lumen that compromises offspring fertility. This study sought to determine the effects of nicotine on the viability and function of purified pig pre-pubertal SC. Nicotine exposure reduced the mRNA expression and protein levels of anti-Mullerian hormone (AMH) and inhibin B and impaired FSH-r sensitivity via the downregulation of FSH-r and aromatase gene expression compared to untreated SC. Overall, our study suggests that nicotine can significantly alter extracellular matrix and tight junction protein gene expression (e.g., laminin, integrin, and occludin), thus compromising cross-talk between the interstitial and tubular compartments and enhancing blood-testis barrier (BTB) permeability via downregulation of the mitogen-activated protein kinase (MAPK) pathway. These findings further elucidate a potential mechanism of action underlying nicotine exposure's detrimental effects on SC function in vivo.

Rotenone is an environmental neurotoxin that induces degeneration of dopaminergic neurons and the most common features of Parkinson's disease in animal models. It acts as a mitochondrial complex I inhibitor that impairs cellular respiration, with consequent increase of reactive oxygen species and oxidative stress. This study evaluates the rotenone-induced oxidative damage in PC12 cells, focusing particularly on protein oxidation. The identification of specific carbonylated proteins highlighted putative alterations of important cellular processes possibly associated with Parkinson's disease. Carbonylation of ATP synthase and of enzymes acting in pyruvate and glucose metabolism suggested a failure of mechanisms ensuring cellular energy supply. Concomitant oxidation of cytoskeletal proteins and of enzymes involved in the synthesis of neuroactive molecules indicated alterations of the neurotransmission system. Carbonylation of chaperon proteins as well as of proteins acting in the autophagy-lysosome pathway and the ubiquitin-proteasome system suggested the possible formation of cytosolic unfolded protein inclusions as result of defective processes assisting recovery/degradation of damaged molecules. In conclusion, this study originally evidences specific protein targets of rotenone-induced oxidative damage, suggesting some possible molecular mechanisms involved in rotenone toxicity.

Background Currently available studies show that removal of subjects affected by occupational asthma from exposure does not always lead to an improvement in respiratory function. The cause of this is still unclear. The aim of our study was to evaluate in 2017 lung function and severity of asthma in subjects who underwent specific inhalation challenge (SIC) between 2006 and 2015 for work-related asthma. Methods Clinical charts of 35 workers who underwent SIC have been evaluated. They were interviewed by telephone using a questionnaire to asses demographic data, respiratory symptoms and work disability. The severity of asthma was evaluated according to the GINA guidelines and asthma control was assessed by Asthma Control Questionnaire (ACQ). 18 workers agreed also to perform also spirometry. Results 10 subjects had a positive SIC and 25 a negative SIC. Subjects with positive SIC had more frequently moderate persistent asthma treated with a combination of inhaler steroids and a bronchodilator (67%) and those with negative SIC had more frequently intermittent asthma (65%) treated with salbutamol as needed (p Conclusions Subjects who have had a positive SIC showed more severe asthmatic symptoms with lower asthma control despite current pharmacological therapy. They also had a higher RV than subjects with negative SIC. This could be a relevant parameter to evaluate in subjects with occupational asthma to improve asthma control.

In Parkinson’s disease (PD), respiratory disturbances have been reported and the effect of levodopa on respiratory function remains controversial. The objective of this study was to evaluate pulmonary function utilizing spirometric and subjective evaluations in mild to moderated PD. Thirty-four consecutive sporadic PD patients (Hoehn and Yahr scale: 1–3) were prospectively evaluated using clinimetric scales, spirometry and modified Borg scale, all in off- and on-conditions. To check the respiratory function, a follow-up was performed at 4 years in a subgroup of these patients. Spirometric results were normal for all patients in both the on- and off-conditions at baseline. After levodopa administration, in addition to a significant improvement in subjective state of breathing discomfort, the mean forced expiratory volume in 1 s (FEV1), vital capacity (VC), forced vital capacity (FVC) values and their mean percentages predicted values (FEV1%, VC%, FVC%) were significantly increased (p

Objectives: We evaluated the effects of the Italian 2005 smoking ban in public places on the prevalence of smoking, quitting and cigarette consumption of young workers. Data and Methods: The dataset was obtained from non-computerized registers of medical examinations for a population of workers with apprenticeship contracts residing in the province of Viterbo, Italy, in the period 1996–2007. To estimate the effects of the ban, a segmented regression approach was used, exploiting the discontinuity introduced by the application of the law on apprentices’ smoking behavior. Results: It is estimated that the Italian smoking ban generally had no effect on smoking prevalence, quitting ratio, or cigarette consumption of apprentices. However, when the estimates were applied to subpopulations, significant effects were found: −1% in smoking prevalence, +2% in quitting, and −3% in smoking intensity of apprentices with at least a diploma.

Glyoxalase I (Glo1) is a cellular defense enzyme involved in the detoxification of methylglyoxal (MG), a cytotoxic by-product of glycolysis, and MG-derived advanced glycation end products (AGEs). Argpyrimidine (AP), one of the major AGEs coming from MG modification of protein arginines, is a proapoptotic agent. Crystalline silica is a well-known occupational health hazard, responsible for a relevant number of pulmonary diseases. Exposure of cells to crystalline silica results in a number of complex biological responses, including apoptosis. The present study was aimed at investigating whether, and through which mechanism, Glo1 was involved in Min-U-Sil 5 crystalline silica-induced apoptosis. Apoptosis, by TdT-mediated dUTP nick-end labeling assay, and transcript and protein levels or enzymatic activity, by quantitative real-time PCR, Western blot, and spectrophotometric methods, respectively, were evaluated in human bronchial BEAS-2B cells exposed or not (control) to crystalline silica and also in experiments with appropriate inhibitors. Reactive oxygen species were evaluated by coumarin-7-boronic acid or Amplex red hydrogen peroxide/peroxidase methods for peroxynitrite (ONOO(-)) or hydrogen peroxide (H2O2) measurements, respectively. Our results showed that Min-U-Sil 5 crystalline silica induced a dramatic ONOO(-)-mediated inhibition of Glo1, leading to AP-modified Hsp70 protein accumulation that, in a mechanism involving JNK and NF-κB, triggered an apoptotic mitochondrial pathway. Inhibition of Glo1 occurred at both functional and transcriptional levels, the latter occurring via ERK1/2 MAPK and miRNA 101 involvement. Taken together, our data demonstrate that Glo1 is involved in the Min-U-Sil 5 crystalline silica-induced BEAS-2B cell mitochondrial apoptotic pathway via a novel mechanism involving Hsp70, JNK, and NF-κB. Because maintenance of an intact respiratory epithelium is a critically important determinant of normal respiratory function, the knowledge of the mechanisms underlying its disruption may provide insight into the genesis, and possibly the prevention, of a number of pathological conditions commonly occurring in silica dust occupational exposure.

Background: Asbestos-related diseases remain a significant occupational health problem in much of the world. Evidence of asbestos exposure is not always apparent in routine clinical evaluations of potentially exposed individuals, particularly in the initial stages of pathogenesis, so convenient biomarkers of exposure could be useful in the early identification of individuals at risk. Methods and findings: Based on prior research, we examined serum levels of kinesin family proteins (KIF5A and KIF18A) and p53 autoantibodies in 198 asbestosexposed workers and 164 unexposed controls. Exposed individuals were significantly more likely to have increased KIF5A and decreased KIF18A compared to the unexposed controls; p53 autoantibodies and exposure were unrelated. Conclusion: Serum kinesins may be useful biomarkers of asbestos exposure.

Whether exposure to 50-60Hz extremely low frequency magnetic fields (ELF-MF) exerts neurotoxic effects is a debated issue. Analogously, the potential role of Aluminum (Al) in neurodegeneration is a matter of controversial debate. As all living organisms are exposed to ELF-MF and/or Al daily, we found investigating the early effects of co-exposure to ELF-MF and Al in SH-SY5Y and SK-N-BE-2 human neuroblastoma (NB) cells intriguing. SH-SY5Y5 and SK-N-BE-2 cells underwent exposure to 50Hz ELF-MF (0.01, 0.1 or 1mT) or AlCl3 (4 or 40μM) or co-exposure to 50Hz ELF-MF and AlCl3 for 1h continuously or 5h intermittently. The effects of the treatment were evaluated in terms of DNA damage, redox status changes and Hsp70 expression. The DNA damage was assessed by Comet assay; the cellular redox status was investigated by measuring the amount of reduced glutathione (GSH) and glutathione disulfide (GSSG) while the inducible Hsp70 expression was evaluated by western blot analysis and real-time RT-PCR. Neither exposure to ELF-MF or AlCl3 alone induced DNA damage, changes in GSH/GSSG ratio or variations in Hsp70 expression with respect to the controls in both NB cell lines. Similarly, co-exposure to ELF-MF and AlCl3 did not have any synergic toxic effects. The results of this in vitro study, which deals with the effects of co-exposure to 50Hz MF and Aluminum, seem to exclude that short-term exposure to ELF-MF in combination with Al can have harmful effects on human SH-SY5Y and SK-N-BE-2 cells.

IntroductionIn 2010, the International Agency for Research on Cancer (IARC) classified ‘Shiftwork that involves circadian disruption’ as a probable human carcinogen (group 2A), based on limited evidence from epidemiological studies and sufficient evidence from experimental animal studies. The epidemiological results were consistent for breast cancer. More recent publications suggested an increase in risk for ovarian and endometrial cancer, prostate cancer, and colorectal cancer.Sleep deprivation is common in shift workers, and it leads to disruption of the transcription of genes implicated in the regulation of the immune response.ObjectivesAs depression of the immune system is a known risk factor for lymphomas, we explored the association between risk of lymphoma subtypes and nightshift work with a case-control study design.Materials and methodsBased on the lifetime occupational history available for 323 cases and 463 controls who participated in a case-control study on lymphoma etiology conducted in Sardinia (Italy) in 1998–2006, expert occupational physicians assessed nightshift work for each job entry of each study subject. We calculated risk of major lymphoma subtypes, namely diffuse large B cell lymphoma, follicular lymphoma, chronic lymphocytic leukemia, multiple myeloma and Hodgkin lymphoma, associated with cumulative days of nightshift work with unconditional logistic regression, adjusting by age, gender, and education.ResultsNone of the lymphoma subtypes we investigated showed an association with lifetime cumulative days of nightshift work. Contrary to our expectation, risk of all lymphomas combined tended to decrease with cumulative days of nightshift work.ConclusionsFurther studies are warranted to investigate in more detail whether sleep deprivation resulting from nightshift work might be implicated in lymphomagenesis. Future investigations should include information on the chronotype of study subjects, the specific shift rotation schedule applied in each workplace, usual hours of sleep per day, and occurrence of daytime sleepiness.

Long-term exposure to high manganese (Mn) levels can lead to Parkinson-like neurological disorders. Molecular mechanisms underlying Mn cytotoxicity have been not defined. It is known that Mn induces apoptosis in PC12 cells and that this involves the activation of some signal transduction pathways. Although the role of phospholipids in apoptosis and signal transduction is well-known, the membrane phospholipid component in Mn-related damage has not yet been investigated. Phosphatidylserine (PS) facilitates protein translocation from cytosol to plasma membrane and PS exposure on the cell surface allows macrophage recognition of apoptotic cells. This study investigates the effects of MnCl2 on PS metabolism in PC12 cells, relating them to those on cell apoptosis. Apoptosis induction decreased PS radioactivity of PC12 cells incubated with radioactive serine. MnCl2 reduced PS radioactivity even under conditions that did not affect cell viability or PS exposure, suggesting that the effects on PS metabolism may represent an early event in cell apoptosis. Thus the latter conditions that also induced a greater PS decarboxylation were utilized for further investigating on the effects on PS synthesis, by measuring the activity and expression of PS-synthesizing enzymes, in cell lysates and in total cellular membranes (TM). Compared with corresponding controls, enzyme activity of MnCl2-treated cells was lower in cell lysates and greater in TM. Evaluating the expression of two isoforms of PS-synthesizing enzyme (PSS), PSSII was increased both in cell lysate and TM, while PSSI was unchanged. MnCl2 addition to control cell lysate reduced enzyme activity. These results suggest Mn plays a dual role on PS synthesis. Once inside the cell, Mn inhibits the enzyme/s, thus accounting for reduced PS synthesis in lysates and intact cells. On the other hand, it increases PSSII expression in cell membranes. The possibility that this occurs to counteract the direct effects of Mn ions on enzyme activity cannot be excluded. The effects on membrane enzyme activity and expression may also participate to PS exposure, observed at longer periods of treatment, by increasing membrane PS content.

Reactive oxygen species (ROS) are implicated in the regulation of apoptosis through a number of distinct mechanisms depending on cell type and stimulation conditions. Glyoxalase I (GI) metabolizes methylglyoxal (MG) and MG-derived advanced glycation end products (AGEs) known to cause apoptosis. This study examined the possible role of GI among the mechanisms of ROS-driven apoptosis in human bronchial epithelial BEAS-2B cells exposed to wood dust and signaling pathways by which these reactive species regulate GI expression. Our results showed that wood dust generated distinct ROS (superoxide anion, and hydrogen peroxide) by selectively inhibiting the enzymatic activity of superoxide dismutase or glutathione peroxidase and catalase enzymes. These ROS caused a dramatic inhibition of the antiglycation GI enzyme, leading to the intracellular accumulation of the pro-apoptotic AGE, argpyrimidine (AP) and programmed cell death via a mitochondrial pathway. Pre-treatment with N-acetyl-L-cysteine (NAC), a ROS scavenger, prevented these events. Hence, ROS-induced apoptosis in BEAS-2B cells occurred via a novel mechanism relying on GI inhibition and AP accumulation. We interestingly found that superoxide anion and hydrogen peroxide induced a diverse apoptosis level by differently inhibiting GI via NF-κB pathway. Since maintenance of an intact epithelium is a critically important determinant of normal respiratory function, the knowledge of the mechanisms underlying its disruption may provide insight into the genesis of a number of pathological conditions commonly occurring in wood dust occupational exposure. Our findings suggest that the antioxidant NAC may merit investigation as a potential preventive agent in wood dust exposure-induced respiratory diseases.

Work-related asthma is one of the most relevant work-related diseases worldwide, causing a high socio-economical burden. In the last decades, many countries experienced huge modifications in work organisations. These changes made people to move from traditional sectors to the tertiary sectors and non-industrial indoor working environments. Non-industrial indoor workplaces are characterised by a new concept of building, with a new structure, new materials, forced ventilation, tight construction and a potential exposure to new risk factors for work-related asthma, such as new chemicals and biological agents able to cause or exacerbate asthma. The actual scientific evidence suggests an increased risk of asthma among workers exposed to cleaning agents in indoor working environment and moulds in damp buildings. Also volatile organic compounds (VOCs) and environmental tobacco smoke could be considered triggers of asthma, even if their role is still under debate. Because of the increasing numbers of subjects working in non-industrial indoor environments and the scientific evidence of an increased risk of asthma in indoor environment, there is a need of public health intervention towards the prevention of work-related asthma, also in this specific setting.

Objective Dioxin, a known risk factor for lymphoma, and numerous other xenobiotics, induce their own metabolism by initially activating the aryl hydrocarbon receptor (AhR). We used the serum samples of participants to the multicentre Italian study on gene-environment interactions in lymphoma aetiology (ITGxE) to explore AhR activation as an intermediate step in dioxin-induced risk of lymphoma, and particularly B-cell lymphoma subtypes. Methods Overall, serum samples of 343 lymphoma cases and 1899 population and hospital controls from five Italian areas (Florence, Bari, Perugia, Novara, and central and southern Sardinia) were available for study. A 50 microliter serum aliquot of each study participant potentially carrying the AhR activator, was added to HepG2 cells, transfected with specific reporter systems including the DRE specific AhR activating sequence upstream to the luciferase reported gene. The intensity of light generated by the Dual-Luciferase Assay, captured with a luminometer, is directly correlated with the concentration and potency of the inducing xenobiotic. Risk of lymphoma overall and by its major B-cell specific subtypes associated with AhR activation positivity as a binary outcome was calculated using an unconditional logistic regression model adjusted by age and gender. Results Among the B-cell lymphoma subtypes, there was a significant two-fold excess risk for follicular lymphoma (OR = 2.0, 95% CI: 1.0, 4.0) and chronic lymphocytic leukaemia (OR = 2.3, 95% CI: 1.0, 5.0). No increase in risk associated with AhR positivity was observed for the other B-cell lymphoma subtypes we tested, namely diffuse large B-cell lymphoma, and multiple myeloma, nor for Hodgkin lymphoma. Conclusions Our results show that the Dual-Luciferase Assay is a reliable and inexpensive test to detect AhR activation and its role in lymphomagenesis.

Introduction: Polyciclic aromatic hydrocarbons (PAH) are environmental pollutants produced by incomplete combustion of organic materials; some of which are carcinogens and associated to cardiovascu...

Glyoxalase I (Glo1) is the main scavenging enzyme of methylglyoxal (MG), a potent precursor of advanced glycation end products (AGEs). AGEs are known to control multiple biological processes, including epithelial to mesenchymal transition (EMT), a multistep phenomenon associated with cell transformation, playing a major role in a variety of diseases, including cancer. Crystalline silica is a well-known occupational health hazard, responsible for a great number of human pulmonary diseases, such as silicosis. There is still much debate concerning the carcinogenic role of crystalline silica, mainly due to the lack of a causal demonstration between silica exposure and carcinogenesis. It has been suggested that EMT might play a role in crystalline silica-induced lung neoplastic transformation. The aim of this study was to investigate whether, and by means of which mechanism, the antiglycation defence Glo1 is involved in Min-U-Sil 5 (MS5) crystalline silica-induced EMT in BEAS-2B human bronchial epithelial cells chronically exposed, and whether this is associated with the beginning of a neoplastic-like transformation process. By using gene silencing/overexpression and scavenging/inhibitory agents, we demonstrated that MS5 induced hydrogen peroxide-mediated c-Jun-dependent Glo1 up-regulation which resulted in a decrease in the Argpyrimidine-modified Hsp70 protein level which triggered EMT in a novel mechanism involving miR-21 and SMAD signalling. The observed EMT was associated with a neoplastic-like phenotype. The results obtained provide a causal in vitro demonstration of the MS5 pro-carcinogenic transforming role and more importantly they provide new insights into the mechanisms involved in this process, thus opening new paths in research concerning the in vivo study of the carcinogenic potential of crystalline silica.

The International Agency for Research on Cancer has classified several antineoplastic drugs in Group 1 (human carcinogens), among which chlorambucil, cyclophosphamide (CP) and tamoxifen, Group 2A (probable human carcinogens), among which cisplatin, etoposide, N-ethyl- and N-methyl-N-nitrosourea, and Group 2B (possible human carcinogens), among which bleomycins, merphalan and mitomycin C. The widespread use of these mutagenic/carcinogenic drugs in the treatment of cancer has led to anxiety about possible genotoxic hazards to medical personnel handling these drugs. The aim of the present study was to evaluate work environment contamination by antineoplastic drugs in a hospital in Central Italy and to assess the genotoxic risks associated with antineoplastic drug handling. The study group comprised 52 exposed subjects and 52 controls. Environmental contamination was assessed by taking wipe samples from different surfaces in preparation and administration rooms and nonwoven swabs were used as pads for the surrogate evaluation of dermal exposure, 5-fluorouracil and cytarabine were chosen as markers of exposure to antineoplastic drugs in the working environment. The actual exposure to antineoplastic drugs was evaluated by determining the urinary excretion of CP. The extent of primary, oxidative and excision repaired DNA damage was measured in peripheral blood leukocytes with the alkaline comet assay. To evaluate the role, if any, of genetic variants in the extent of genotoxic effects related to antineoplastic drug occupational exposure, the study subjects were genotyped for GSTM1, GSTT1, GSTP1 and TP53 polymorphisms. Primary DNA damage significantly increased in leukocytes of exposed nurses compared to controls. The use of personal protective equipment (i.e. gloves and/mask) was associated with a decrease in the extent of primary DNA damage.

Occupational and environmental exposure to the heavy metal cadmium (Cd) and its inhalation from cigarette smoke are associated with emphysema. Many growth factors and extracellular matrix (ECM) cell signaling molecules are directly involved in the epithelial bronchial cell pathway. This study investigated the direct effects of Cd on the production of several ECM components in human bronchial epithelial cells (BEAS-2B) that were exposed in vitro for 48 h to sub-toxic and toxic concentrations of Cd. Gene expression of collagens, metalloproteases (MMPs), integrins, tenascin and vitronectin were quantified by RT-PCR. To study apoptosis cascade, annexin assay and cellular cytotoxicity by MTT assay were performed. We also investigated whether an imbalance in the TGFβ/TGFβ receptor (TGFβR) expression mediated Cd effects. The results showed the sub-toxic Cd dose significantly increased tenascin, vitronectin, β1 and β5 integrin gene expression. The toxic Cd dose decreased type IV and V collagen, α1, α2 and β3 integrins. Both Cd doses down-regulated type I collagen and up-regulated metalloproteases. Each Cd dose caused a different imbalance in the complex pattern of TGFβ and its receptors. No alteration in classic apoptotic marker protein expression was observed in presence of the sub-toxic dose of Cd, suggesting this metal alters ECM production without apoptotic activation. In conclusion, all these data show even sub-toxic Cd dose exposure alters the specific gene expression of several ECM components that are crucially implicated in the mechanical properties of lung parenchyma supporting the hypothesis that the mechanism underlying Cd-induced lung disease may involve downstream changes in TGFβ/TGFβR signaling.

Background Silicosis is mediated by macrophages, their soluble mediators, and extracellular matrix molecules. In this study, we investigated the effects of silica and/or hyaluronate (HA) on several alveolar macrophage responses. Methods We evaluated glycosaminoglycan (GAG) production by radiolabeled precursors, nitric oxide (NO) release by its oxidation product, phagocytic activity by Candida albicans internalization, and the secretion of two fibrogenic cytokines, tumor necrosis factor (TNF)-α and transforming growth factor (TGF)-β, by specific assays. Results Silica significantly reduced GAG secretion, particularly HA secretion. Alone, it decreased Candida uptake; associated with HA, it enhanced the reduction. Silica and Candida reduced NO release, which was not significantly affected when silica- or Candida-exposed cells were also treated with HA. TNF-α and TGF-β activities were stimulated by silica but reduced by HA. Conclusions The results suggest that silica and HA modify alveolar macrophage functional differentiation. Silica- and HA-induced modifications of the microenvironment could determine whether the response proceeds toward healing and repair or toward lung chronic pathology.

Background The diagnosis of chronic obstructive pulmonary disease (COPD) is based on airflow obstruction. In epidemiological studies, spirometric data have often been lacking and researchers have had to rely almost solely on questionnaire answers. The aim of this study is to assess the diagnostic accuracy of questionnaire answers to detect COPD. Methods A sample of the Swedish general population without physician-diagnosed asthma was randomly selected and interviewed using a respiratory questionnaire. All eligible subjects aged 25–75 years (n = 3892) performed spirometry for detection of airflow obstruction using Global Initiative for Chronic Obstructive Lung Disease (GOLD) or American Thoracic Society (ATS)/European Respiratory Society (ERS) criteria. Sensitivity, specificity, positive likelihood ratio (LR+), positive predictive values (PPVs), and negative predictive values (NPVs) were calculated to define diagnostic accuracy of questionnaire answers. Results The sensitivity of the question “Have you been diagnosed by a physician as having COPD or emphysema?” in detecting airflow obstruction was 5.7% using GOLD, and 9.8% using ATS/ERS, criteria; specificity was 99.7% for GOLD and 99.5% for ATS/ERS. Sensitivity, specificity, and PPV were higher for the question compared to self-reported symptoms of chronic bronchitis in identifying subjects with airflow obstruction. Conclusions The high specificity and good PPV suggest that the question “Have you been diagnosed by a physician as having COPD or emphysema?” is more likely to identify those who do not have airflow obstruction, whereas the low sensitivity of this question could underestimate the real burden of COPD in the general population.

Several epidemics of nicotine intoxication have been described among tobacco harvesters; however, little is known about nicotine absorption under typical working conditions. To assess systemic nicotine absorption during a regular working shift, the authors performed an observational field study. Included in the study were 10 healthy, nonsmoking, female tobacco harvesters and a control group of 5 healthy, nonsmoking, female hospital workers. Nicotine and cotinine were measured in sequential samples of blood and urine during a regular workshift. Blood nicotine levels rose from a nadir value of 0.79 +/- 0.12 ng/ml to a peak value of 3.45 +/- 0.84 ng/ml (p < .05 [Tukey's modified t test]) in the exposed group. In the control group, levels were stable at 0.1 +/- 0.1 ng/ml (p < .01). Moreover, the mean blood nicotine level measured 3 mo following the end of exposure in 6 of 10 exposed subjects was 0.24 +/- 0.12 ng/ml (p < .01). Corresponding higher values of urine nicotine and urine cotinine were observed in the exposed versus control group (comparative p values were < .01 and < .05, respectively). Overall, tobacco harvesters absorbed approximately 0.8 mg of nicotine daily. Given that nicotine can induce adverse health effects, the authors believe that prevention of nicotine absorption in tobacco harvesters should be sought and that workers should be informed about occupational risks.

We investigated whether the presence of (+)-anti-benzo(a)pyrene diolepoxide adducts to serum albumin (BPDE-SA) among workers exposed to benzo(a)pyrene (BaP) and unexposed reference controls was influenced by genetic polymorphisms of cytochrome P4501A1 (CYP1A1), microsomal epoxide hydrolase (EHPX), glutathione S-transferases M1 (GSTM1) and P1 (GSTP1), all involved in BaP metabolism. Exposed workers had significantly higher levels of adducts (0.124 ± 0.02 fmol BPTmg(-1) SA, mean ± SE) and a higher proportion of detectable adducts (40.3%) than controls (0.051 ± 0.01 fmol BPT mg(-1) SA; 16.1%) (p = 0:014 and p = 0:012). Smoking increased adduct levels only in occupationally exposed workers with the GSTM1 deletion (GSTM1 null) (p = 0:034). Smokers from the exposed group had higher adduct levels when they were CYP1A1 *1/*1 wild-type rather than heterozygous and homozygous for the variant alleles (CYP1A1 *1/*2 plus *2/*2) (p = 0:01). The dependence of BPDE-SA adduct levels and frequency on the CYP1A1 *1/*1 genotype was most pronounced in GSTM1-deficient smokers. Exposed workers with GSTM1 null/GSTP1 variant alleles had fewer detectable adducts than those with the GSTM1 null/GSTP1*A wild-type allele, supporting for the first time the recent in vitro finding that GSTP1 variants may be more effective in the detoxification of BPDE than the wild-type allele. Logistic regression analysis indicated that occupational exposure, wild-type CYP1A1*1/*1 allele and the combination of GSTM1 null genotype+EHPX genotypes associated with predicted low enzyme activity were significant predictors of BPDE-SA adducts. Though our findings should be viewed with caution because of the relatively limited size of the population analysed, the interaction between these polymorphic enzymes and BPDE-SA adducts seems to be specific for high exposure and might have an impact on the quantitative risk estimates for exposure to polycyclic aromatic hydrocarbons.

The CC16 microprotein is the main secretory product of Clara cells, which are epithelial cells lining lung airways. In crossing through the bronchoalveolar/blood barrier, CC16 diffuses passively into plasma. Serum CC16 (sCC16) has recently been proposed as a biomarker for detecting Clara cell impairments. The aim of this study was to assess if sCC16 concentrations are reduced in a group of healthy young smokers. A group of 118 healthy young males volunteered to take part in the study. Each subject answered a questionnaire, and provided blood and urine samples. Serum CC16, urinary cotinine and creatinine were measured. Median serum CC16 concentrations were lower in smokers than in non-smokers (11.3 mug l(-1) vs 14.6 mug l(-1); p = 0.005; N = 89 and 29, respectively) but did not correlate with either the daily or the life-time cigarette consumption, or with urinary cotinine concentrations. sCC16 did not correlate with age or body mass index in the whole study population or in the groups of smokers and non-smokers. These results suggest the reduction in sCC16 concentrations in a group of healthy young smokers may be an early effect of cigarette smoking.

The present molecular epidemiology study was carried out to evaluate the genotoxic effects of occupational exposure to antineoplastic drugs (ANP). The study was conducted in 52 hospital workers involved in the preparation, handling or administration of ANP in a hospital in Perugia (central Italy) and in 52 non-exposed control subjects matched for age, gender and smoking habits to the exposed subjects. Both comet assay and the micronucleus test were used to evaluate genome damage in peripheral blood lymphocytes in study subjects. The extent of primary DNA damage, as evaluated by the comet assay, was significantly increased in exposed personnel with respect to matched controls. On the other hand, no significant differences in micronuclei frequency was observed between the two groups. Multivariate linear regression analysis showed an association between years of occupational exposure over 10 years and higher extent of primary DNA damage in the exposed group. The results of this study confirm that handling ANP without appropriate precautions carries a genotoxic risk for exposed healthcare workers. These results address the need for regular biological effect monitoring of staff occupationally-exposed to ANP.

The role of the occupational health services in the assessment and management of indoor air quality (IAQ) problems in non-industrial sectors (offices, banks, etc.) has been discussed by experts of the ICOH Scientific Committee on IAQ and Health and has been proposed as follow: 1. Collaboration in risk assessment--risk management; 2. Questionnaire survey; 3. Health surveillance (only when periodical health surveillance is already performed for other risks or when specific clinical examination of workers is required); 4. Health promotion (programs for a better IAQ management). A team approach with cooperation between medical and technical experts is recommended in the assessment and management of indoor air quality problems.

and MN rates. Conclusions: Concerning the aim of this study to evaluate the genotoxic risk arising from occupational exposure to ANPDs, statistically significant differences in MN rates in the subjects under study could not be determined. (J Occup Health 2012; 54: 405-415) Antineoplastic drugs (ANPDs) are a heterogeneous group of chemicals that include alkylating agents (e.g., cyclophosphamide, melphalan, chlorambucil), antime - tabolites (e.g., thioguanine, 5-fluorouracil, methotrex - ate), antibiotics (e.g., doxorubicin), mitotic spindle inhibitors (e.g., vincristine), hormones (e.g., diethyl - Abstract: Biological Effect Monitoring in Peripheral Blood Lymphocytes from Subjects Occupationally Exposed to Antineoplastic Drugs: Assessment of Micronuclei Frequency: Milena VILLARINI, et al. Department of Medical-Surgical Specialties and Public Health (Section of Public Health), University of Perugia, Italy—Objectives: Antineoplastic drugs (ANPDs) are widely used in the treatment of cancer and some nonneoplastic diseases. However, most if not all of these chemical agents are generally nonselective and, along with tumor cells, normal cells may undergo cytotoxic/genotoxic damage. Italian pharmacists and nurses occupationally exposed to ANPDs during their normal work routines were monitored to evaluate biological effects (i.e., cytogenetic damage) eventually associated with exposure. The subjects were also monitored for primary, oxidative and excision repaired DNA damage as evaluated by comet assay (published data). In the present paper, we present the results obtained with the cytokinesis-block micronucleus (CBMN) test. Methods: The CBMN test in peripheral blood lymphocytes was applied because of its ability to detect both clastogenic and aneugenic effects, and because it has recently been reported that micronuclei (MNs) are predictive of cancer risk in human popula- tions. In this study, the evaluation of MN frequency was carried out using the CBMN test in the absence or in the presence of the DNA repair inhibitor Ara-C (cytosine arabinoside). Results: No significant difference was observed for MN frequency comparing nurses handling ANPDs (exposed subjects) and controls; no correlations were found between job seniority, age, smoking habits

Objective: Hexavalent chromium (Cr(VI)) compounds are widely found in different working environments. These compounds can cause apoptosis in human cells, but the mechanisms underlying chromium-induced apoptosis are not clear. A marker of apoptosis is the exposure of phosphatidylserine on cell membrane and the modification of phosphatidylserine metabolism. The aim of this study was to verify whether chromium could cause phosphatidylserine exposure and modification of its metabolism in human lymphoblastic leukemia cell line (MOLT-4). Methods: Phosphatidylserine exposure was evaluated by annexin V binding whereas phosphatidylserine metabolism was studied measuring the incorporation of [3H]serine. Results: Cell treatment with Cr(VI) increases phosphatidylserine exposure and cell apoptosis, but decreases the incorporation of [3H]serine into phosphatidylserine in a dose- and time-dependent manner. Conclusions: The Cr(VI)-induced apoptosis also through modification of phosphatidylserine exposure and metabolism.

Carbon monoxide (CO) poisoning is still common, especially in houses where the sources of CO are numerous and particularly insidious. In 1991, we observed 11 people who were affected by acute CO poisoning; 8 cases of which occurred in the home and 3 in the working environment. Home poisoning often affected more than one person; the cause of the intoxication was always the result of a faulty heating system associated with poor ventilation of rooms. Our experience confirms that CO is an insidious threat more common than is generally believed which can cause incidences of extremely dangerous poison ing, sometimes representing a difficult challenge to medical practitioners. A deeper knowledge and correct prevention of this problem are the primary means of reducing the proportions of this risk.

Reactive oxygen species (ROS) play an important role as mediators of pulmonary damage in mineral dust-induced diseases. Studies carried out to date have largely focused on silica-induced production of ROS by lung phagocytes. In this study we investigated the hypothesis that crystalline silica Min-U-Sil 5 can induce elevations in intracellular ROS in human bronchial epithelial cells BEAS-2B, via an indirect mechanism that involves ROS-inducing intracellular factors, through a reduction of antiglycation (glyoxalase enzymes) and antioxidant (paraoxonase 1 and glutathione-S-transferases) enzymatic defenses. The results show that crystalline silica Min-U-Sil 5 causes a significant reduction in the efficiency of antiglycation and antioxidant enzymatic defenses, paralleled by an early and extensive ROS generation, thus preventing the cells from an efficient scavenging action, and eliciting oxidative damage. These results confirm the importance of ROS in development of crystalline silica-induced oxidative stress and emphasize the pivotal role of antiglycation/antioxidant and detoxifying systems in determining the level of protection from free radicals-induced injury for cells exposed to crystalline silica Min-U-Sil 5.

Background Silicosis is caused by inhaling free crystalline silica. Few case reports have addressed the risk of silicosis in the jewelry trade where chalk molds containing a high percentage of silica are used in casting. We conducted a cross-sectional study involving 100 goldsmiths exposed to silica. Methods All workers replied to a questionnaire and underwent a clinical examination, pulmonary function tests, a chest X-ray and a high-resolution CT scan. Results High-resolution CT visualized signs of silicosis in 23 cases, confirmed by standard chest X-rays in 10. In the 23 workers with CT evidence of silicosis Total Lung Capacity, FEV1 and the Lung Diffusing Capacity did not differ from the workers without the disease. Pulmonary function tests did not correlate with silica exposure. Conclusion In this study we demonstrate that use of chalk molds in casting in jewelry causes silicosis. The composition of the dust could be responsible of the high prevalence observed. Am. J. Ind. Med. 50:577–583, 2007. © 2007 Wiley-Liss, Inc.

Background The results of a cross-sectional study aimed to evaluate whether genetic polymorphisms (biomarkers of susceptibility) for CYP1A1, EPHX and GSTM1 genes that affect polycyclic aromatic hydrocarbons (PAH) activation and detoxification might influence the extent of primary DNA damage (biomarker of biologically effective dose) in PAH exposed workers are presented. PAH-exposure of the study populations was assessed by determining the concentration of 1-hydroxypyrene (1OHP) in urine samples (biomarker of exposure dose). Methods The exposed group consisted of workers (n = 109) at a graphite electrode manufacturing plant, occupationally exposed to PAH. Urinary 1OHP was measured by HPLC. Primary DNA damage was evaluated by the alkaline comet assay in peripheral blood leukocytes. Genetic polymorphisms for CYP1A1, EPHX and GSTM1 were determined by PCR or PCR/RFLP analysis. Results 1OHP and primary DNA damage were significantly higher in electrode workers compared to reference subjects. Moreover, categorization of subjects as normal or outlier highlighted an increased genotoxic risk OR = 2.59 (CI95% 1.32–5.05) associated to exposure to PAH. Polymorphisms in EPHX exons 3 and 4 was associated to higher urinary concentrations of 1OHP, whereas none of the genotypes analyzed (CYP1A1, EPHX, and GSTM1) had any significant influence on primary DNA damage as evaluated by the comet assay. Conclusion The outcomes of the present study show that molecular epidemiology approaches (i.e. cross-sectional studies of genotoxicity biomarkers) can play a role in identifying common genetic risk factors, also attempting to associate the effects with measured exposure data. Moreover, categorization of subjects as normal or outlier allowed the evaluation of the association between occupational exposure to PAH and DNA damage highlighting an increased genotoxic risk.

The present study investigated the sources of discomfort and the symptoms reported by earthquake victims residing in temporary emergency prefabricated accommodation (prefab). The investigation was carried out by means of a questionnaire. 203 prefab occupants and 132 inhabitants of houses, who were chosen as reference population, replied in winter and 233 prefab occupants and 154 inhabitants of houses replied in summer. In both seasons more people living in prefabs identified dry air, stuffy air, stale air, dust, dampness, uncomfortable temperature and bad odours as sources of discomfort. They also complained of general symptoms (headache, irritability, insomnia, difficulty in concentration) and irritative symptoms of the eyes, upper and lower airways and skin. Multiple regression analysis identified the type of accommodation as the variable that most influenced the onset of general, ocular, upper and lower airway symptoms. Intrinsic characteristics of the prefabs (being constructed with synthetic materials, combustion sources, poor ventilation and insulation) and psychosocial factors e. losing their home, could have contributed to the onset of symptoms.