Prevalence of respiratory symptoms and disorders among rice mill workers in India

Objectives

Lung function tests have become an integral part of assessment of pulmonary disease. Diseases of the respiratory system induced by occupational dusts are influenced by the duration of exposure. The aim of the study is to investigate the impairment of lung function and prevalence of respiratory symptoms among the rice mill workers.

Methods

A total of 120 rice mill workers from three districts of Karnataka were included in this study. Fifty urban dwellers from the same socio-economic level were selected as controls. The study included clinical examination, assessment of respiratory symptoms, pulmonary function test, measurement of peak expiratory flow rate, absolute eosinophil count, ESR estimation, total IgE estimation and radiographic test.

Results

The present study has shown that the rice mill workers complained of several types of respiratory disorders like phlegm (40.8 %), dyspnea (44.2 %), chest tightness (26.7 %), cough (21.7 %), and nose irritation (27.5 %). Rice mill workers exposed to dust presented significantly (p < 0.05) lower levels of FVC (3.44 ± 0.11), FEV₁ (2.73 ± 0.15) and PEFR (304.95 ± 28.79) than the controls. The rice mill workers are having significantly higher absolute eosinophil counts, total IgE and ESR than control groups. The hematological findings suggest that the harmful effects may be linked to both non-specific irritation and allergic responses to rice husk dust among rice mill workers.

Conclusion

Dust exposure in the working environment affects the lung function values and increased the respiratory symptoms among the rice mill workers.     

Inflammatory response to acute exposure to welding fumes during the working day

Objectives

To investigate cardiorespiratory and inflammatory responses in male workers following exposure to welding fumes and airborne particles in actual workplace conditions.

Materials and Methods

We measured blood leukocytes and their differential counts, platelet count, hemoglobin, sensitive C-reactive protein, fibrinogen, E-selectin, IL-(interleukin)1β, IL-6, IL-8, tumor necrosis factor alpha (TNF-α) and endothelin-1 in blood samples of twenty workers before and after their working day. We also studied peak expiratory flow (PEF), forced expiratory volume in one second (FEV₁), and exhaled nitric oxide (NO). We assessed heart rate variability (HRV) by obtaining 24-hour ambulatory electrocardiograms.

Results

The total blood leukocytes and neutrophils increased after the work shift, whereas IL-1β and E-selectin decreased significantly. There were no statistically significant changes in exhaled NO, FEV₁, PEF or HRV.

Conclusion

Occupational exposure to welding fumes and particles caused a slight, acute inflammatory effect estimated based on the increased values of leukocytes and neutrophils in blood and a decrease in the interleukin 1β and E-selectin values, but no changes in the pulmonary function (exhaled NO, FEV₁, PEF) or HRV during the working day were observed.     

Lung function in asphalt pavers: a longitudinal study

Purpose

To study longitudinal changes in lung function in asphalt pavers and a reference group of road maintenance workers, and to detect possible signs of lung disease by high-resolution computed tomography (HRCT) scans.

Methods

Seventy-five asphalt pavers and 71 road maintenance workers were followed up with questionnaires and measurements of lung function. Not every worker was tested every year, but most of them had four or more measurement points. The 75 asphalt pavers were also invited to have HRCT scans of the lungs at the end of the follow-up period.

Results

Mean annual decline in forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV₁) of the asphalt pavers was 58 and 35 ml, respectively. Adjusted for age at baseline, packyears of smoking and BMI, the asphalt pavers had a significant excess annual decline in FVC and FEV₁ compared to the references. The screedmen, the most exposed group of the asphalt pavers, showed a significantly larger decline in FVC than the other asphalt pavers (P = 0.029). Fine intralobular fibrosis without evident cysts was identified with HRCT in three subjects (4 %).

Conclusion

We conclude that our findings may indicate an excess annual decline in FVC and FEV₁ related to exposure to asphalt fumes. The screedmen, who carry out their work behind and close to the paving machine, had the largest decline in lung function. The finding of adverse pulmonary effects in asphalt pavers calls for better technological solutions to prevent exposure.

     

An updated historical cohort mortality study of workers exposed to asbestos in a refitting shipyard, 1947�C2007

Purpose

To evaluate the long-term health effects of occupational asbestos exposure, an updated historical cohort mortality study of workers at a refitting shipyard was undertaken.

Methods

The cohort consisted of 249 male ship repair workers (90 laggers, 159 boiler repairers). To determine relative excess mortality, standardized mortality ratios (SMRs) were calculated using mortality rates among the Japanese male population. Mortality follow-up of study subjects was performed for the period from 1947 till the end of 2007.

Results

We identified the vital status of 87 (96.7%) laggers and 150 (94.3%) boiler repairers. Of these, 63 (72.4%) and 95 (63.3%), respectively, died. Laggers, who had handled asbestos materials directly, showed a significantly elevated SMR of 2.64 (95% confidence interval [CI]: 1.06?C5.44) for lung cancer and 2.49 (95% CI: 1.36?C4.18) for nonmalignant respiratory diseases. Boiler repairers, who had many opportunities for secondary exposure to asbestos and a few for direct exposure, showed no significant elevation in SMR for lung cancer but a significantly elevated SMR of 1.78 (95% CI: 1.06?C2.81) for nonmalignant respiratory diseases. In an analysis according to duration of employment, there was a significantly elevated SMR of nonmalignant respiratory diseases in the longer working years group. Among workers from both jobs, no deaths caused by mesothelioma in addition to those in the original study were found and no subject died from larynx cancer.

Conclusion

This updated study confirmed a significant excess of asbestos-related mortality from diseases such as lung cancer and nonmalignant respiratory diseases among workers in a refitting shipyard in Japan.     

Chronic Lung Function Decline in Cotton Textile Workers: Roles of Historical and Recent Exposures to Endotoxin

Background

Long-term occupational exposure to cotton dust that contains endotoxin is associated with chronic respiratory symptoms and excessive decline in forced expiratory volume in 1 sec (FEV₁), but the mechanisms of endotoxin-related chronic airflow obstruction remain unclear.

Objective

In the current study, we examined temporal aspects of the exposure–response relationship between airborne endotoxin exposure, longitudinal change in FEV₁, and respiratory symptoms in a cohort of Chinese cotton textile workers.

Methods

This prospective cohort study followed 447 cotton textile workers from 1981 to 2006.at approximately 5-year intervals. We used a generalized estimating equations approach to model FEV₁ level and respiratory symptoms as a function of past exposure (cumulative exposure up to the start of the most recent 5-year survey interval) and cumulative exposure (within the most recent interval) to endotoxins, after adjusting for other covariates. Models were stratified by active versus retired work status and by years employed before the baseline survey (< 5 and ≥ 5 years).

Results and conclusions

Past exposure to endotoxin was associated with reduced FEV₁ level among retired cotton workers. Among all cotton workers, past exposure was more strongly associated with reduced FEV₁ for those hired < 5 years before baseline than for those who were hired ≥ 5 years after baseline. Recent endotoxin exposure was significantly associated with byssinosis, chronic bronchitis, and chronic cough.     

Pulmonary function impairment and airway allergy among workers in traditional bakeries

Objectives

To assess the effect of exposure to flour dust on pulmonary function tests, prevalence of symptoms (respiratory, allergic/irritating) and parameters of allergic sensitization in terms of skin prick test, and bronchial hyper-responsiveness.

Material and Methods

43 bakers (with at least 2 years of occupational exposure) working at different bakeries in Ismailia city, Egypt; and 64 control subjects of comparable socio demographic characteristics were compared. All participants were subjected to an interview questionnaire, clinical chest examination, skin prick test, bronchial hyper-responsiveness test and measurements of pulmonary function parameters.

Results

All respiratory and allergic symptoms were more prevalent among bakers compared to the control group, with the highest odds ratio for allergic symptoms (OR = 6.9; p < 0.0001) and dyspnea (OR = 6.3; p = 0.0004). Bakers had a higher percentage of SPT positive results with statistically significant difference between the two groups (p < 0.0001). Bakers had lower observed values compared to the control group with statistically significant difference for FVC, FEV₁/FVC ratio, FEF_75%, and FEF_25–75% parameters.

Conclusion

The present study suggested that occupational exposure to flour dust may affect respiratory irritation and sensitization, and reduce the pulmonary function tests such as FVC, FEV₁, and FEV₁/FVC ratio and FEF_25–75%.     

Rapidly measured indicators of recreational water quality and swimming-associated illness at marine beaches: a prospective cohort study

Background

Diverse environmental exposures, studied separately, have been linked to health outcomes in adult asthma, but integrated multi-factorial effects have not been modeled. We sought to evaluate the contribution of combined social and physical environmental exposures to adult asthma lung function and disease severity.

Methods

Data on 176 subjects with asthma and/or rhinitis were collected via telephone interviews for sociodemographic factors and asthma severity (scored on a 0-28 point range). Dust, indoor air quality, antigen-specific IgE antibodies, and lung function (percent predicted FEV₁) were assessed through home visits. Neighborhood socioeconomic status, proximity to traffic, land use, and ambient air quality data were linked to the individual-level data via residential geocoding. Multiple linear regression separately tested the explanatory power of five groups of environmental factors for the outcomes, percent predicted FEV₁ and asthma severity. Final models retained all variables statistically associated (p < 0.20) with each of the two outcomes.

Results

Mean FEV₁ was 85.0 ± 18.6%; mean asthma severity score was 6.9 ± 5.6. Of 29 variables screened, 13 were retained in the final model of FEV₁ (R² = 0.30; p < 0.001) and 15 for severity (R² = 0.16; p < 0.001), including factors from each of the five groups. Adding FEV₁ as an independent variable to the severity model further increased its explanatory power (R² = 0.25).

Conclusions

Multivariate models covering a range of individual and environmental factors explained nearly a third of FEV₁ variability and, taking into account lung function, one quarter of variability in asthma severity. These data support an integrated approach to modeling adult asthma outcomes, including both the physical and the social environment.     

Flexible semiparametric joint modeling: an application to estimate individual lung function decline and risk of pulmonary exacerbations in cystic fibrosis

Background

Epidemiologic surveillance of lung function is key to clinical care of individuals with cystic fibrosis, but lung function decline is nonlinear and often impacted by acute respiratory events known as pulmonary exacerbations. Statistical models are needed to simultaneously estimate lung function decline while providing risk estimates for the onset of pulmonary exacerbations, in order to identify relevant predictors of declining lung function and understand how these associations could be used to predict the onset of pulmonary exacerbations.

Methods

Using longitudinal lung function (FEV₁) measurements and time-to-event data on pulmonary exacerbations from individuals in the United States Cystic Fibrosis Registry, we implemented a flexible semiparametric joint model consisting of a mixed-effects submodel with regression splines to fit repeated FEV₁ measurements and a time-to-event submodel for possibly censored data on pulmonary exacerbations. We contrasted this approach with methods currently used in epidemiological studies and highlight clinical implications.

Results

The semiparametric joint model had the best fit of all models examined based on deviance information criterion. Higher starting FEV₁ implied more rapid lung function decline in both separate and joint models; however, individualized risk estimates for pulmonary exacerbation differed depending upon model type. Based on shared parameter estimates from the joint model, which accounts for the nonlinear FEV₁ trajectory, patients with more positive rates of change were less likely to experience a pulmonary exacerbation (HR per one standard deviation increase in FEV₁ rate of change = 0.566, 95% CI 0.516–0.619), and having higher absolute FEV₁ also corresponded to lower risk of having a pulmonary exacerbation (HR per one standard deviation increase in FEV₁ = 0.856, 95% CI 0.781–0.937). At the population level, both submodels indicated significant effects of birth cohort, socioeconomic status and respiratory infections on FEV₁ decline, as well as significant effects of gender, socioeconomic status and birth cohort on pulmonary exacerbation risk.

Conclusions

Through a flexible joint-modeling approach, we provide a means to simultaneously estimate lung function trajectories and the risk of pulmonary exacerbations for individual patients; we demonstrate how this approach offers additional insights into the clinical course of cystic fibrosis that were not possible using conventional approaches.

     

Initiation of health-behaviour change among employees participating in a web-based health risk assessment with tailored feedback

Background

Biological monitoring of healthy workers exposed to hazardous dusts lack validated screening tools. Induced sputum (IS) cellular profile was compared with bronchoalveolar lavage fluid (BALF) profile in asbestos exposed workers in order to assess its usefulness in monitoring workers exposed to asbestos for a long period of time.

Methods

IS and BALF analysis was performed in 39 workers of a car brakes and clutches factory that uses chrysotile asbestos. Selection criteria were an employment history of > 15 years and the absence of a diagnosis of pneumonoconiosis. The type of cells, the existence of dust cells, of iron laden macrophages and of asbestos bodies were assessed and compared between IS and BALF samples.

Results

35 IS samples (90%) had dust cells, 34 (87%) iron laden macrophages and in 8 samples (21%) asbestos bodies were found. In most samples neutrophils were dominated. Samples with asbestos bodies (ABs) had significantly higher lymphocytes and lower neutrophils count compared with the samples without ABs. Macrophages and neutrophils in IS and BALF exhibited significant inter-relations (Spearman's rho: 0.26-0.29, p < 0.05) while IS lymphocytes count showed an inverse relation with BALF neutrophils (Spearman's rho: -0.36). Neutrophils and dust cells were highly correlated between the samples (Spearman's rho: 0.35, p < 0.05) while IS dust cells and lymphocytes were inversely related (Spearman's rho: -0.36, p < 0.05). More years of employment in the company was related with more neutrophils (Spearman's rho: 0.26) and less lymphocytes (Spearman's rho: -0.33) count. In multivariate analysis the presence of AB in IS samples was strongly related to the presence of asbestos bodies and lymphocytes count in BALF samples.

Conclusions

IS and BALF analysis showed a similar cellular profile indicating that IS sampling in exposed workers to asbestos as a less invasive and expensive method may be useful in providing an insight both for inhalation of dusts and inflammatory processes in the lung.     

Serum carotenoids and pulmonary function in older community-dwelling women

Background and Objectives

Deterioration in pulmonary function is associated with greater disability and mortality in older adults. Dietary antioxidants are implicated in lung health, but the relationship between major dietary antioxidants, such as serum carotenoids, and pulmonary function have not been well characterized. Serum carotenoids are considered the most reliable indicator of fruit and vegetable intake.

Subjects and Methods

We examined the relationship between serum ??-carotene, ??-carotene, ??-cryptoxanthin, lutein/zeaxanthin, and lycopene with pulmonary function (forced expiratory volume in one second [FEV₁] and forced vital capacity [FVC]) in a population-based sample of 631 moderately to severely disabled community-dwelling older women (Women??s Health and Aging Study I) in Baltimore, Maryland, USA.

Results

Higher serum ??-carotene and ??-carotene concentrations were positively associated with both FEV₁ and FVC, respectively (all P < 0.05), in separate multivariate linear regression models adjusting for age, race, education, cognition, anemia, inflammation, and chronic diseases. Total serum carotenoids were associated with FEV1 (P = 0.08) and FVC (P = 0.06), respectively, in similar models. No association was found between ??-cryptoxanthin, lutein/zeaxanthin, and lycopene, and FEV₁ or FVC.

Conclusions

Higher serum ??-carotene and ??-carotene concentrations, which reflect greater intake of orange and dark green leafy fruits and vegetables, were associated with better pulmonary function among older community-dwelling women.function may lead to food avoidance and to a higher incidence of digestive complaints.     

Changes of mesothelin and osteopontin levels over time in formerly asbestos-exposed power industry workers

Purpose

In patients developing malignant pleural mesothelioma (MPM) or lung cancer, using effective tumour markers is the quickest way to ensure early diagnosis and improve survival time. The aim of our study was to assess the influence of age and asbestos exposure on the blood levels of the proposed tumour markers, mesothelin and osteopontin, and to determine the change of these markers over time.

Methods

We analysed 3,329 blood samples of 2,262 participants including 1,894 formerly asbestos-exposed power industry workers, a mixed group of 266 participants with an unknown history of asbestos exposure and a group of 102 non-asbestos-exposed controls. Marker concentrations were determined using commercial ELISA kits.

Results

While age had a strong influence on marker levels, there was no association between exposure duration or benign asbestos-related disease and marker levels. In order to assess the maximum increase that can be expected to occur in asbestos-exposed workers those with an at least 10 % increase were selected (n = 290 for mesothelin and n = 81 for osteopontin). The 95th percentile of the annual change was 0.402 nmol/l for mesothelin and 334 ng/ml for osteopontin. In two patients with MPM and five with lung cancer, we could obtain more than one marker result before the diagnosis was made. Both MPM patients showed a steep increase of mesothelin levels.

Conclusions

Fixed cut-off values for deciding between intensive clinical work-up and continued surveillance appeared inadequate for the evaluated markers. While general conclusions cannot be drawn, we can say that the results of the two patients would be consistent with a mesothelin increase between 6 and 18 months before clinical symptoms developed.     

Occupational asthma follow-up — which markers are elevated in exhaled breath condensate and plasma?

Objectives

To search for optimal markers in the exhaled breath condensate (EBC), plasma and urine that would reflect the activity/severity of occupational asthma (OA) after the withdrawal from the exposure to the allergen.

Material and Methods

Markers of oxidative stress: 8-iso-prostaglandin {ie206-1} (8-isoprostane, 8-ISO), malondialdehyde (MDA), 4-hydroxy-trans-2-nonenale (HNE), cysteinyl leukotrienes (LT) and LTB₄ were determined using liquid chromatography and mass spectrometry in 43 subjects with immunological OA (49.3±11.8 years), removed from the exposure to the sensitizing agent 10.5±6.5 years ago; and in 20 healthy subjects (49.0±14.9 years). EBC was harvested both before and after the methacholine challenge test. In parallel, identical markers were collected in plasma and urine. The results were analyzed together with forced expiratory volume in one second (FEV₁), blood eosinophils, immunoglobulin E (IgE) and eosinophilic cationic protein (ECP) and statistically evaluated (Spearman rank correlation r_S, two- or one-sample t tests and alternatively Kruskal Wallis or pair Wilcoxon tests).

Results

Several parameters of lung functions were lower in the patients (FEV1% predicted, MEF25% and MEF50%, Rtot%, p < 0.001). Shorter time interval since the removal from the allergen exposure correlated with higher ECP (r_S = 0.375) and lower FEV₁%, MEF25% and MEF50% after methacholine challenge (r_S = ?0.404, ?0.425 and ?0.532, respectively). In the patients, IgE (p < 0.001) and ECP (p = 0.009) was increased compared to controls. In EBC, 8-ISO and cysteinyl LTs were elevated in the asthmatics initially and after the challenge. Initial 8-ISO in plasma correlated negatively with FEV₁ (r_S = ?0.409) and with methacholine PD₂₀ (r_S = ?0.474). 8-ISO in plasma after the challenge correlated with IgE (r_S = 0.396).

Conclusions

The improvement in OA is very slow and objective impairments persist years after removal from the exposure. Cysteinyl LTs and 8-ISO in EBC and 8-ISO in plasma might enrich the spectrum of useful objective tests for the follow-up of OA.     

Across-shift changes of exhaled nitric oxide and spirometric indices among cotton textile workers

Objectives

For the purpose of evaluation of exhaled NO as an index of airway inflammation, we assessed changes in fractional exhaled NO (FeNO) across a work shift and its relationship with respiratory complaints.

Material and Methods

Chronic and work-aggravated respiratory complaints were assessed using a questionnaire in 89 male textile workers. FeNO and spirometry were performed before and after a work shift and all the changes were registered.

Results

A significant increase in FeNO after a work shift was observed. Post-shift FeNO was significantly higher among the subjects with chronic respiratory complaints. There was an obvious decrease in FVC, and FEV₁ after a work shift; however, we couldn’t find a significant relationship between changes in respiratory parameters and concentration of inhalable dusts.

Conclusions

FeNO increase after a work shift along with pulmonary function decrement and higher post-shift FeNO among subjects with respiratory complaints makes across-shift FeNO a non-invasive test for assessment of airway hyper-responsiveness in textile workers.     

Progression of small, irregular opacities in chest radiographs of former asbestos workers

Objectives

Pulmonary parenchymal changes appear many years after the start of exposure to asbestos and their progression has been observed to continue many years after cessation of the exposure. The aim of the present analysis is to assess the risk of progression of radiological changes in the respiratory system, based on long-term follow-up of groups of workers occupationally exposed to asbestos dust.

Materials and Methods

The analysis included 3144 individuals voluntarily applying for a medical examination in 2000–2010, who had performed at least two radiographs of the chest. Probability of progression in subsequent studies was based on the evaluation of radiographs for the presence of small, irregular type s, t, u opacities in the parenchymal lung tissue with profusion categories as specified in the classification of ILO, 1980. Multistate hidden Markov model was used in the statistical analysis.

Results

In the group of patients, small irregular opacities with a profusion of 1/1 or higher occurred in 640 (20%) patients in the first examination, and in 918 (29%) patients in the last examination. No parenchymal changes were observed in 1360 (43%) patients in the first examination (opacity profusion category 0/0), and in 645 (20%) patients in the last examination. The risk of progression of radiographic changes in former workers of asbestos processing plants is higher in smokers, from profusion category 0 to 1 — by 30% (HR = 1.30, 95% CI: 1.15–1.47), from profusion category 1 to 2 — by 50% (HR = 1.50, 95% CI: 0.92–2.45). The risk of progression of parenchymal changes decreases in the workers employed in subsequent calendar years: for category changes from 1 to 2, the decrease is nearly 40% for every 10 years of subsequent employment (HR = 0.60, 95% CI: 0.45–0.80). The probability of the progression increases with longer latency period: for change of category from 1 to 2, the increase is about 20% (HR = 1.19, 95% CI: 1.00–1.42) per 10 years of employment for blue collar workers. The risk of the 1 to 2 category progression is significant, nearly 2.5-fold higher in the workers employed in the asbestos-processing textile industry.

Conclusions

Our results show that the risk of progression of pulmonary parenchymal fibrotic processes was higher in the smokers, workers employed during the earlier calendar years of the discussed period, those with longer latency period, blue collar workers involved directly in the production processes, and employees of the asbestos cement and/or textile industries.     

Renal impairment caused by chronic occupational chromate exposure

Purpose

To determine the nephritic toxicity of chromate after chronic occupational exposure.

Methods

The environmental contamination was assessed by measuring the chromium (Cr) in 8-h airborne sampler. The integrated level of Cr was determined by Cr concentrations in the whole blood (WB-Cr) and the urine (U-Cr). The renal glomerular and tubule impairment was evaluated by determination of cystatin C (Cys-C) in the serum and microalbumin (mALB), urinary beta₂-microglobulin (??₂M), N-acetyl-beta-d-glucosaminidase (NAG) activity in the urine.

Results

The mean occupational exposure time to Cr was 12.86?years with average daily air level of 27.13???g/m³ comparing to 0.11???g/m³ of the background level. The WB-Cr and U-Cr were 23.49???g/L and 17.41???g/g creatinine (Cre), respectively in the chromate-exposed workers comparing to 3.32???g/L and 1.52???g/g Cre in the controls. The serum Cys-C and urinary mALB were significantly increased in the chromate-exposed workers. Exposure to Cr seems to induce an enhanced level of urinary NAG activity and ??₂M concentration. The increased serum Cys-C concentration was positively correlated with the level of serum Cre. The U-Cr was positively correlated to the concentrations of urinary mALB, ??₂M, and the activity of NAG.

Conclusions

Chronic occupational exposure to chromate causes comprehensive renal impairment though more severity could occur in the tubule than in the glomeruler.     

Polymorphisms in the p53 pathway genes and micronucleus occurrence in Chinese vinyl chloride-exposed workers

Objectives

To investigate the association between polymorphisms in the p53 pathway genes and chromosomal damage in vinyl chloride (VC)-exposed workers.

Materials and Methods

Cytokinesis block micronucleus test was performed in 310 VC-exposed workers and 149 non-exposed workers to determine chromosomal damage. The polymerase chain reaction and restriction fragment length polymorphism technique were used to detect six SNPs in the p53 pathway genes involved in the cell cycle.

Results

There was a highly significant dose-response relationship between VC exposure and chromosomal damage. Individuals carrying the variant genotypes were at higher risk for chromosomal damage compared with their wild type genotype: p53rs1042522, MDM2 Del1518rs3730485, MDM2rs2279744 and GADD45Ars532446. On the other hand, individuals possessing the variant genotype of CDKN2A rs3088440 had significantly decreased risk compared with the corresponding wild-type.

Conclusions

Genetic polymorphisms in P53 pathway genes may have an impact on VC-induced chromosomal damage.     

Association of clinical findings in Yusho patients with serum concentrations of polychlorinated biphenyls, polychlorinated quarterphenyls and 2,3,4,7,8-pentachlorodibenzofuran more than 30 years after the poisoning event

Background

Adverse respiratory effects of particulate air pollution have been identified by epidemiological studies. We aimed to examine the health effects of ambient particulate air pollution from wood burning on school-age students in Christchurch, New Zealand, and to explore the utility of urine and exhaled breath condensate biomarkers of exposure in this population.

Methods

A panel study of 93 male students (26 with asthma) living in the boarding house of a metropolitan school was undertaken in the winter of 2004. Indoor and outdoor pollution data was continuously monitored. Longitudinal assessment of lung function (FEV₁ and peak flow) and symptoms were undertaken, with event studies of high pollution on biomarkers of exposure (urinary 1-hydroxypyrene) and effect (exhaled breath condensate (EBC) pH and hydrogen peroxide concentration).

Results

Peak levels of air pollution were associated with small but statistically significant effects on lung function in the asthmatic students, but not healthy students. No significant effect of pollution could be seen either on airway inflammation and oxidative stress either in healthy students or students with asthma. Minor increases in respiratory symptoms were associated with high pollution exposure. Urinary 1-hydroxypyrene levels were raised in association with pollution events by comparison with low pollution control days.

Conclusion

There is no significant effect of ambient wood-smoke particulate air pollution on lung function of healthy school-aged students, but a small effect on respiratory symptoms. Asthmatic students show small effects of peak pollution levels on lung function. Urinary 1-hydroxypyrene shows potential as a biomarker of exposure to wood smoke in this population; however measurement of EBC pH and hydrogen peroxide appears not to be useful for assessment of population health effects of air pollution. Some of the data presented in this paper has previously been published in Kingham and co-workers Atmospheric Environment, 2006 Jan; 40: 338–347 (details of pollution exposure), and Cavanagh and co-workers Sci Total Environ. 2007 Mar 1;374(1):51-9 (urine hydroxypyrene data).     

Role of occupational asbestos exposure in Hungarian lung cancer patients

Objective: What is the frequency of occupational asbestos exposure among patients suffering from malignant respiratory tumours and how many of these tumours are associated with asbestos in Hungary? Methods: An internationally established questionnaire with 29 questions, covering the most characteristic activities of asbestos exposure at the workplace was completed for 300 patients with respiratory malignancies, i.e. 297 patients with lung cancer and three with mesothelioma of the pleura. From the questionnaire, the smoking habits were estimated and cumulative asbestos exposure was assessed in fibre-years. Additionally, lung X-rays were classified and the national data on the incidence of malignant pleura mesothelioma were analysed. Results: A cumulative asbestos exposure of 25?fibre-years or more was detected in 11 patients with lung cancer (4%) and in each of the three patients with pleural mesothelioma (100%). In a further 72 patients (24%), cumulative occupational asbestos exposure was assessed as below 25?fibre-years (between 0.01 and 23.9?fibre-years). In this group, car and truck mechanics, and installation and construction workers using asbestos-cement were registered. Among patients with an asbestos exposure of 25?fibre-years or more, six asbestos-cement production workers were observed, among them the three mesothelioma cases. A weak but significant association between positive X-ray findings and exposure estimates could be demonstrated. Additionally, results of the lung tissue fibre counts by scanning transmission electron microscopy were available for 25 of the lung cancer patients. A good correlation was observed between the asbestos fibre counts and the assessment of cumulative asbestos exposure. In Hungary, 84 cases of pleural mesothelioma were registered in 1997 and 73 in 1998. These numbers correspond to an annual incidence of about one new case per 100,000 inhabitants older than 15?years. Conclusions: The annual incidence of lung cancer in Hungary is about 6,000. Since in our series of lung cancer patients about 4% were observed, which could be accepted as representing occupational disease because of a cumulative exposure to 25?fibre-years or more, the annual asbestos related lung tumour incidences may be estimated to be approximately 150 or more. The proportion of nearly two estimated cases of lung cancer per case of pleural mesothelioma corresponds to international experience. Up to now, lung cancer cases only exceptionally have been registered as occupational diseases, i.e. they were seriously under-diagnosed in Hungary. For improving this situation, diagnostic assistance by a self-interview with a questionnaire covering the working history for all newly diagnosed lung cancer patients would be helpful.     

Lung function decline and blood lead among residents nearby to industrial complex

Purpose

This study was to ascertain the risk factors of pulmonary function decline (forced expiratory volume in 1?s [FEV₁], forced vital capacity [FVC]) among those exposed to lead in the vicinity of industrial complex.

Methods

In total, 263 men and women, aged over 30, were recruited from two cities during a 2-year follow-up. Spirometry testing was conducted first at baseline and then after 2-years of follow-up. The change in FVC and FEV₁ during the study period was analyzed according to blood lead (BPb), urinary cotinine, and 1-hydroxypyrene, after controlling for sex, height, baseline FVC or FEV₁, and airway hyperresponsiveness.

Results

With increase in age, both FEV₁ and FVC declined. More marked decline in FVC was noted for men than for women (p?<?0.05), while the decline in FEV₁ was not. Biological variables, especially height (p?<?0.05) and pulmonary status (p?<?0.0001), were associated with the decline in both FEV₁ and FVC. Even after controlling these other variables, blood lead level was also significantly associated with the decline of FVC.

Conclusions

Even though the decline in FEV₁ and FVC with aging was within a normal range, people with smaller height were more vulnerable to the decline of both FEV₁ and FVC and especially higher level of BPb was accompanied with larger decline of FVC. Oxidative stress in relation to lead accumulation in adult may contribute to rapid aging of pulmonary function.     

Prevalence of occupational exposure to asbestos and crystalline silica according to phenotypes of lung cancer from the CaProMat study: A case‐only study

Background

The objective of the study was to compare the prevalence of occupational exposure to asbestos and crystalline silica according to histological types of lung cancer and age at diagnosis.

Methods

CaProMat study is a pooled case‐only study conducted between 1996 and 2011. The current study consisted of 6521 lung cancer cases. Occupational exposure to asbestos and crystalline silica was assessed by two Job‐Exposure Matrices. A weighted prevalence of exposure was derived and compared according to histological types and age at diagnosis.

Results

There was no difference of weighted prevalence of exposure to asbestos and crystalline silica according to histological types of lung cancer. There was a statistically significant difference of weighted prevalence of exposure to asbestos and crystalline silica according to age at diagnosis.

Conclusions

Due to the limited clinical importance of the difference, neither the histological type, nor the age at diagnosis can be used as an indicator for the occupational exposure to asbestos or crystalline silica.