Asbestos Exposure Assessment Research Articles

A functional regression model for the retrospective assessment of asbestos exposure among Venetian dock workers

A functional regression model for the retrospective assessment of asbestos exposure among Venetian dock workers

Assessment of worst-case potential airborne asbestos exposure associated with the use of cosmetic talc: application of an exponential decay model.

Talc is used in cosmetic products to confer desirable properties, such as moisture absorption and smooth texture, to the finished products. Concerns have been raised about the potential presence of asbestos in products containing cosmetic talc. Reconstruction of potential asbestos exposure from the use of cosmetic talc products (assuming a trace level of asbestos) requires consideration of consumer use patterns. Although application generally only lasts seconds, exposure theoretically may continue if the consumer remains in the immediate vicinity. Most published exposure measurements have not adequately characterized the potential for continued exposure. In this analysis, estimates and measurements of airborne asbestos fiber concentrations associated with cosmetic talc use from 10 published studies were used as inputs to an exponential decay model to estimate "worst-case" exposure during and following application. The resulting geometric mean 30-min time-weighted average (TWA) concentrations were 0.006 f/cc for both puff and shaker application, for diapering, 0.0001f/cc (adult applying baby powder) and 0.0002 f/cc (infant), and for makeup application, 0.0005 f/cc. Application of an exponential decay model to measured or estimated asbestos concentrations associated with the use of cosmetic talc products yields a conservative means to comprehensively reconstruct such exposures. Moreover, our results support that, if a cosmetic talc powder product contained a trace level of asbestos fibers, the "worst-case" airborne asbestos exposure associated with its application is low.

The assessment of asbestos exposure of mesothelioma cases registered in Italy: which problems more than thirty years after the birth of the first regional archives

More than 30 years have passed since the beginning of the epidemiological surveillance of mesothelioma (MM). The Italian National Mesothelioma Register (ReNaM), part of the research department of the National Institute for insurance against industrial injuries (INAIL), has published 7 reports with the description of the cas-es concerning the assessment of diagnoses and exposures to asbestos suffered mainly during working activities but also environmental, in the family premises and during personal activities.Today we are witnessing a reduction in the commitment by some regions which negatively affects those who develop the pathology. Reading the ReNaM reports it emerges, among others, the problem of the delay in reporting new cases which limits the collection of information directly from patients. This contribution, discussing various topics, invites to develop a debate that should allow to update and resolve the critical aspects that arise after decades of activity regarding, in particular, the asbestos exposure assessment. It is the primary interest of the authors to give continuity and improve the ReNaM which remains the most prestigious MM register among those active in other countries.

Assessment of Asbestos Exposure Associated with a Brake Grinder

Assessment of Asbestos Exposure Associated with a Brake Grinder

Serous Ovarian Cancer Caused by Exposure to Asbestos and Fibrous Talc in Cosmetic Talc Powders-A Case Series.

Asbestos is a known cause of ovarian cancer. We report 10 cases of serous ovarian cancer among users of Johnson & Johnson (J&J) asbestos-containing "cosmetic" talc products. We conducted an asbestos exposure assessment during talc application and analyzed surgical tissues and talc containers for asbestos and talc. Talc was found in all cases and tremolite and/or anthophyllite asbestos was found in 8/10 cases. The asbestos fibers found in the "cosmetic" talc containers matched those found in tissues. We estimated inhaled asbestos dose ranged from 0.38 to 5.18 fiber years. We provide evidence that the inhaled dose of asbestos/fibrous talc from "cosmetic" talc use causes ovarian cancer. The unique combination of the types of asbestiform minerals detected in cancerous tissue and "cosmetic" talc is a fingerprint for exposure to asbestos-containing talc.

Pulmonary Function and CT Scan Imaging at Low-Level Occupational Exposureto Asbestos.

Background: In spite of the reduced exposure level, and its ban in numerous countries, compensation claims for asbestos-related diseases are far from decreasing. Methods: We used retrospective exposure assessment techniques to explore respiratory function and a computerized tomography (CT) scan in relation to past asbestos exposure in 115 male workers retired from an acrylic and polyester fiber plant. Based, on detailed information on exposure circumstances, we reconstructed a cumulative exposure estimate for each patient. Results: Time-weighted average exposure in our study population was 0.24 fibers/ml (95% confidence inteval (CI) 0.19–0.29), and the average cumulative exposure was 4.51 fibers/mL-years (95% CI 3.95–5.07). Exposure was elevated among maintenance workers, compared to other jobs (p = 0.00001). Respiratory function parameters did not vary in relation to the exposure estimates, nor to CT scan results. Risk of interstitial fibrosis showed a significant upward trend (Wald test for trend = 2.62, p = 0.009) with cumulative exposure to asbestos; risk associated with 5.26 fibers/mL-years or more, was 8-fold (95% CI 1.18–54.5). Conclusions: Our results suggest that a CT scan can detect pleuro-parenchymal lung alterations at asbestos exposure levels lower than previously thought, in absence of respiratory impairment. Further studies are required to validate our techniques of retrospective assessment of asbestos exposure.

The Assessment of Asbestos Exposure Using Semi-Quantitative Approach and Its Impact on Indonesian Male-Workers’ Health

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Spatial analysis of asbestos exposure and occupational health care in Poland during the period 2004-2013.

Asbestos is carcinogenic to humans and exposure to this substance can cause a wide range of diseases. In Poland 1997, a statutory ban was introduced on the production, use and marketing of products containing asbestos. The National Programme for Asbestos Abatement for 2009-2032 includes scheduled activities considering asbestos exposure assessment and health protection. As there are several data sources for asbestos exposure in Poland, which are not linked, the aim of this study was to gather and order them developing a PostgreSQL database, an open-source, objectrelational system. The data gathered combines the following information: the quantity of asbestos-cement products in use, details of asbestos manufacturing plants, the results of the measurements of asbestos fibre concentrations in the air and cases of asbestos-related diseases. The relational database was then used to develop a spatial analysis of asbestos monitoring and exposure in Poland to demonstrate the current state of realisation of the National Asbestos Abatement Programme in the country for 2009-2032 with the use of geoinformation techniques. The use of a database on health aspects of occupational and environmental asbestos exposure was also proposed in Asbestos, Asbestosis, and Cancer: Helsinki Criteria update 2014.

석면함유 조경석 석면 노출평가

2012년 석면안전관리법의 시행으로 인하여 학교 및 건축물 내 건축자재로 사용된 석면에 대한 조사가 이루어졌고 석면함유 건 축자재로 인한 피해를 예방하기 위한 관리방안에 대한 연구가 활발히 진행되고 있다. 그러나 생활공간 주변의 석면함유물질로 석 면함유 조경석 등이 있으나 홍보 및 관리방안 수립없이 방치되어 있는 실정이다. 본 연구는 석면함유 조경석 주변의 공기 중 석면 농도와 이용객들이 석면조경석에 앉아 휴식을 취할 경우 피복에 부착되는 석면의 노출농도 조사·평가 및 관리방안으로 발수코 팅제 도포시 저감효율을 검토하였다. 석면함유 조경석이 시공된 안양 삼성천 생태하천 보도구간과 서울 목동 양정고등학교 도로 변 지역에 대하여 공기 중 석면농도 측정 분석과 이용객들이 휴식을 위해 석면조경석 위에 앉는 행위 를 테이프를 붙였다 떼는 행 위와 물티슈로 문지르는 행위로 가정하여 테이프 및 물티슈에 부착실험을 실시하였다. 실험결과 석면함유 조경석 주변지역의 공 기 중 석면농도는 1 f/cc 미만으로 실내공기질 관리기준 이내인 것으로 확인되었다. 부착실험은 테이프 및 물티슈에 부착된 물질 중 석면의 중량 %로 분석하였으며, 석면농도는 테이프 부착실험 18.3~24.9%, 물티슈 1.5~3.3%로 분석되었다. 단순하게 석면함 유 조경석에 앉는 행위만 하여도 피복에 부착된 부착물 중 1.5~24.9% 가 석면이며, 이는 석면함유 건축자재의 석면함유량 기준인 1%를 초과하는 값으로 관리가 필요한 수준으로 판단된다. 또한 석면함유 조경석에 대해 발수코팅제에 의한 저감효율을 검토한 결 과, 테이프 접촉실험은 88.77~92.67%, 물티슈 접촉실험은 98.12~98.70%의 석면농도가 저감되는 것으로 분석되어 발수코팅제의 시공으로 노출영향을 저감 할 수 있음을 확인하였다.

The effects of improving the mesothelioma surveillance network on sensitivity, timeliness in reporting and asbestos exposure assessment.

In Italy, Mesothelioma Registries (MRs) have been established by law for the epidemiological surveillance of occupational cancers. MRs collect information about asbestos exposure of incident cases, through interviews. In the Emilia-Romagna region, MR was implemented in 1996 and extended its network of health professionals who report suspected mesothelioma in 2001 and 2007. This study evaluated the impact of the extension of the network on MR sensitivity and timeliness. Mesothelioma cases were analysed in three subsequent periods: 1996-2001 (before any network extension), 2002-2007 (after first extension) and 2008-2014 (after second extension). Sensitivity was evaluated by the proportion of cases directly reported by the network out of the total number of incident cases; reporting and interview timeliness were assessed by median times between diagnosis and, respectively, reporting and interview. Pleural mesothelioma reporting timeliness was also evaluated by use of quantile regression models, stratified by diagnostic certainty and adjusted by sex and age. Sensitivity increased from 79.4% (1996-2001), to 89.0% (2002-2007) and to 91.4% (2008-2013). For mesothelioma with diagnostic certainty, we recorded considerably reduced reporting times from the 50th percentile on, whereas for uncertain mesothelioma relevant reductions were observed also in the lower percentiles. A reduced time to interview was observed too, which was more significant for uncertain cases. The proportion of patients directly interviewed increased from 33.5% (1996-2001), to 39.1% (2002-2007), to 49.5% (2008-2014). The extended network improved the MR sensitivity and allowed shorter reporting and interview times and more frequent patient interviews, thus improving accuracy of exposure definition.

Anxious and depressive symptoms in the French Asbestos-Related Diseases Cohort: risk factors and self-perception of risk.

Asbestos is known to be an independent risk factor for lung and pleural cancers. However, to date, little attention has been paid to the psychological effects of asbestos exposure among exposed subjects. The objectives of this study were to estimate the prevalence of anxious and depressive symptoms among >2000 French participants of the Asbestos-Related Diseases Cohort (ARDCO), 6 years after their inclusion, to identify the risk factors associated with those anxious and depressive symptoms and to evaluate the impact of the asbestos-risk perception. The ARDCO was constituted in four regions of France between October 2003 and December 2005, by including former asbestos workers. Between 2011 and 2012, participants of the ARDCO program were invited to undergo another chest CT scan 6 years after the previous scan. Participants were asked to complete questionnaires including asbestos exposure assessment, Hospital Anxiety and Depression Scale (HADS), asbestos-risk perception and self-perception of asbestos-related diseases. Among the 2225 participants, 2210 fully completed questionnaires were collected and analyzed. The prevalence of symptoms of probable anxiety and probable depression was 19.7% and 9.9%, respectively. The risk of anxious and depressive symptoms was independently associated with self-perception of the intensity of asbestos exposure, asbestos-risk perception and self-perception of asbestos-related diseases. The results obtained in this large study confirm that previously asbestos-exposed subjects are likely to develop anxious and depressive symptoms. Finally, implications related to the prevention of anxiety and depression among asbestos-exposed workers is discussed.

Assessment of asbestos exposure during a simulated agricultural activity in the proximity of the former asbestos mine of Balangero, Italy

The natural occurrence of asbestos (NOA) in rural areas is a serious concern for human health and the dispersion route of asbestos in the proximity of natural asbestos-rich settings has been marginally evaluated so far. NOA may affect air, but also water and soil quality. In rural areas population may be exposed to asbestos with a largely unknown impact on human health. This work investigates the potential exposure of a farmer cultivating a field nearby the largest former asbestos mine of Western Europe (Balangero, Italy). The concentration of waterborne asbestos in the stream used to water the field was measured (ca. 2×105 fibers per liter, ff/L) and the cultivated ultramafic topsoil characterized, evidencing a remarkable occurrence of chrysotile. The worker’s personal exposure and the environmental fiber dispersion during a simulated agricultural activity (tillage) were quantified in two independent trials. During the trials, the worker was exposed to average concentrations of 16 and 26ff/L, with a peak of 40ff/L. These data inform about the possible exposure of an agricultural worker to asbestos concentration higher than the accepted threshold of 2ff/L. The release of asbestos fibers into the environment was negligible (0–2ff/L).

Multiple pathway asbestos exposure assessment for a Superfund community.

Libby, MT, USA, was the home to workers at a historical vermiculite mining facility and served as the processing and distribution center for this industrial product that was contaminated with amphibole asbestos. Several pathways of environmental asbestos exposure to the general population have been identified. The local clinic and health screening program collects data from participants on past occupational and environmental exposures to vermiculite and asbestos. Health studies among this population have demonstrated associations between amphibole exposure and health outcomes, but critical questions regarding the nature and level of exposure associated with specific outcomes remain unanswered. The objective of this study was to develop a comprehensive exposure assessment approach that integrates information on individuals' contact frequency with multiple exposure pathways. For 3031 participants, we describe cumulative exposure metrics for environmental exposures, occupational exposures, and residents' contact with carry-home asbestos from household workers. As expected, cumulative exposures for all three occupational categories were higher among men compared with women, and cumulative exposures for household contact and environmental pathways were higher among women. The comprehensive exposure assessment strategies will advance health studies and risk assessment approaches in this population with a complex history of both occupational and environmental asbestos exposure.

Use of Direct Versus Indirect Preparation Data for Assessing Risk Associated with Airborne Exposures at Asbestos-contaminated Sites

At asbestos-contaminated sites, exposure assessment requires measurement of airborne asbestos concentrations; however, the choice of preparation steps employed in the analysis has been debated vigorously among members of the asbestos exposure and risk assessment communities for many years. This study finds that the choice of preparation technique used in estimating airborne amphibole asbestos exposures for risk assessment is generally not a significant source of uncertainty. Conventionally, the indirect preparation method has been less preferred by some because it is purported to result in false elevations in airborne asbestos concentrations, when compared to direct analysis of air filters. However, airborne asbestos sampling in non-occupational settings is challenging because non-asbestos particles can interfere with the asbestos measurements, sometimes necessitating analysis via indirect preparation. To evaluate whether exposure concentrations derived from direct versus indirect preparation techniques differed significantly, paired measurements of airborne Libby-type amphibole, prepared using both techniques, were compared. For the evaluation, 31 paired direct and indirect preparations originating from the same air filters were analyzed for Libby-type amphibole using transmission electron microscopy. On average, the total Libby-type amphibole airborne exposure concentration was 3.3 times higher for indirect preparation analysis than for its paired direct preparation analysis (standard deviation = 4.1), a difference which is not statistically significant (p = 0.12, two-tailed, Wilcoxon signed rank test). The results suggest that the magnitude of the difference may be larger for shorter particles. Overall, neither preparation technique (direct or indirect) preferentially generates more precise and unbiased data for airborne Libby-type amphibole concentration estimates. The indirect preparation method is reasonable for estimating Libby-type amphibole exposure and may be necessary given the challenges of sampling in environmental settings. Relative to the larger context of uncertainties inherent in the risk assessment process, uncertainties associated with the use of airborne Libby-type amphibole exposure measurements derived from indirect preparation analysis are low. Use of exposure measurements generated by either direct or indirect preparation analyses is reasonable to estimate Libby-type Amphibole exposures in a risk assessment.

Differential mutation profiles and similar intronic TP53 polymorphisms in asbestos-related lung cancer and pleural mesothelioma

Given the interest in defining biomarkers of asbestos exposure and to provide insights into asbestos-related and cell-specific mechanisms of neoplasia, the identification of gene alterations in asbestos-related cancers can help to a better understanding of exposure risk. To understand the aetiology of asbestos-induced malignancies and to increase our knowledge of mesothelial carcinogenesis, we compared genetic alterations in relevant cancer genes between lung cancer, induced by asbestos and tobacco smoke, and malignant pleural mesothelioma (MPM), a cancer related to asbestos, but not to tobacco smoke. TP53, KRAS, EGFR and NF2 gene alteration analyses were performed in 100 non-small cell lung cancer (NSCLC) patients, 50 asbestos-exposed and 50 unexposed patients, matched for age, gender, histology and smoking habits. Detailed assessment of asbestos exposure was based on both specific questionnaires and asbestos body quantification in lung tissue. Genetic analyses were also performed in 34 MPM patients. TP53, EGFR and KRAS mutations were found in NSCLC with no link with asbestos exposure. NF2 was only altered in MPM. Significant enhancement of TP53 G:C to T:A transversions was found in NSCLC from asbestos-exposed patients when compared with unexposed patients (P = 0.037). Interestingly, TP53 polymorphisms in intron 7 (rs12947788 and rs12951053) were more frequently identified in asbestos-exposed NSCLC (P = 0.046) and MPM patients than in unexposed patients (P < 0.001 and P = 0.012, respectively). These results emphasise distinct genetic alterations between asbestos-related thoracic tumours, but identify common potential susceptibility factors, i.e. single nucleotide polymorphisms in intron 7 of TP53. While genetic changes in NSCLC are dominated by the effects of tobacco smoke, the increase of transversions in TP53 gene is consistent with a synergistic effect of asbestos. These results may help to define cell-dependent mechanisms of action of asbestos and identify susceptibility factors to asbestos.

OccIDEAS for Asbestos exposure assessment in the Australian Mesothelioma Registry

ObjectivesTo assess asbestos exposure from all sources for all cases of mesothelioma reported to the Australian Mesothelioma Registry (AMR).MethodsOccIDEAS is an expert system database developed to assist experts in the...

A meta-analysis of asbestos and lung cancer: is better quality exposure assessment associated with steeper slopes of the exposure-response relationships?

Background: Asbestos is a well-recognized cause of lung cancer, but there is considerable between-study heterogeneity in the slope of the exposure–response relationship.Objective: We considered the role of quality of the exposure assessment to potentially explain heterogeneity in exposure–response slope estimates.Data sources: We searched PubMed MEDLINE (1950–2009) for studies with quantitative estimates of cumulative asbestos exposure and lung cancer mortality and identified 19 original epidemiological studies. One was a population-based case–control study, and the others were industry-based cohort studies.Data extraction: Cumulative exposure categories and corresponding risks were abstracted. Exposure–response slopes [KL (lung cancer potency factor of asbestos)] were calculated using linear relative risk regression models.Data synthesis: We assessed the quality of five exposure assessment aspects of each study and conducted random effects univariate and multivariate meta-regressions. Heterogeneity in exposure–response relationships was greater than expected by chance (I2 = 64%). Stratification by exposure assessment characteristics revealed that studies with well-documented exposure assessment, larger contrast in exposure, greater coverage of the exposure history by exposure measurement data, and more complete job histories had higher meta-KL values than did studies without these characteristics. The latter two covariates were most strongly associated with the KL value. Meta-KL values increased when we incrementally restricted analyses to higher-quality studies.Conclusions: This meta-analysis indicates that studies with higher-quality asbestos exposure assessment yield higher meta-estimates of the lung cancer risk per unit of exposure. Potency differences for predominantly chrysotile versus amphibole asbestos-exposed cohorts become difficult to ascertain when meta-analyses are restricted to studies with fewer exposure assessment limitations.

Assessment of airborne asbestos exposure at an asbestos cement sheet and pipe factory in Iran

Iran imports nearly 55,000 metric tons of asbestos per year, and asbestos cement (AC) plants contribute nearly 94% of the total national usage. In the present study, asbestos fiber concentrations during AC sheet and pipe manufacturing were measured by phase-contrast microscopy (PCM) and polarized light microscopy (PLM) in 98 personal air samples. The fiber type and its chemical composition were also evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). Personal monitoring of fiber levels indicated a range from 0.02 to 0.55 PCM f/ml (0.02–0.69 PLM f/ml). The AC workers’ geometric mean asbestos exposure was 0.09 PCM f/ml (0.11 PLM f/ml), with arithmetic mean of 0.13 PCM f/ml (0.16 PLM f/ml). The observed fiber concentrations in many processes were higher than the threshold limit value (TLV) proposed by the American Conference of Governmental Industrial Hygienists (ACGIH), which is 0.1 f/ml. Based on these findings, the PLM values were approximately 25% higher than PCM values. The SEM data demonstrate that fibrous particles contained chrysotile. The thinnest fiber recognized by SEM had a diameter of 0.2 μm. Mean exposure exceeded the TLV for asbestos in pipe molding and finishing (100%) as well as sheet molding and finishing (45.5–83.3%). In conclusion exposure control may be needed to be in compliance with the ACGIH TLV and other guidance levels. Also, with regard to PCM limitations for airborne fiber analysis, the use of microscopic methods other than PCM can be used to improve the techniques used presently.

Asbestos in Poland: Occupational health problems

The presentation addresses current problems of health risk and health effects associated with exposure to asbestos, including data on historical exposure and on currently valid occupational exposure limits. The quantity and types of the raw material used for the production of various asbestos products have also been discussed in relation to the particular types of asbestos-induced occupational diseases. The authors describe the medical care system for former asbestos workers and those currently exposed during removal of asbestos-containing products. The national system for medical certification of occupational asbestos-related diseases and the compensation procedure have been outlined as well. According to the parliamentary Act of 1997, importing, manufacture and sale of asbestos and asbestos-containing materials are prohibited in Poland. Thus, the assessment of asbestos exposure and the monitoring of health conditions of workers at asbestos-processing plants have become irrelevant. However, the delayed health effects attributable to past exposure continue to be the matter of concern for public health. Likewise, the environmental pollution from asbestos waste landfills in the vicinity of asbestos-processing plants (where high levels of asbestos fibre in ambient air have been recorded) will continue to be a serious public health problem. Presently, two programmes aimed at minimising the adverse effects of asbestos on population health are underway. One of them is the governmental programme for "Elimination of asbestos and asbestos-containing products used in Poland, 2002-2032". The programme was updated in 2009 to cover the workers contracted to perform demolition works and provide protective covers to asbestos waste landfills. This will be the exposed group who need prophylactic health care. The other is a programme of prophylactic examinations for former asbestos workers and is referred to as the AMIANTUS programme. Both programmes have been briefly described.

CDKN2A, NF2, and JUN are dysregulated among other genes by miRNAs in malignant mesothelioma—A miRNA microarray analysis

Malignant mesothelioma (MM) is an aggressive cancer arising from mesothelial cells, mainly due to former asbestos exposure. Little is known about the microRNA (miRNA) expression of MM. miRNAs are small noncoding RNAs, which play an essential role in the regulation of gene expression. This study was carried out to analyze the miRNA expression profile of 17 MM samples using miRNA microarray. The analysis distinguished the overall miRNA expression profiles of tumor tissue and normal mesothelium. Differentially expressed miRNAs were found in tumor samples compared with normal sample. Twelve of them, let-7b*, miR-1228*, miR-195*, miR-30b*, miR-32*, miR-345, miR-483-3p, miR-584, miR-595, miR-615-3p, and miR-885-3p, were highly expressed whereas the remaining nine, let-7e*, miR-144*, miR-203, miR-340*, miR-34a*, miR-423, miR-582, miR-7-1*, and miR-9, were unexpressed or had severely reduced expression levels. Target genes for these miRNAs include the most frequently affected genes in MM such as CDKN2A, NF2, JUN, HGF, and PDGFA. Many of the miRNAs were located in chromosomal areas known to be deleted or gained in MM such as 8q24, 1p36, and 14q32. Furthermore, we could identify specific miRNAs for each histopathological subtype of MM. Regarding risk factors such as smoking status and asbestos exposure, significantly differentially expressed miRNAs were identified in smokers versus nonsmokers (miR-379, miR-301a, miR-299-3p, miR-455-3p, and miR-127-3p), but not in asbestos-exposed patients versus nonexposed ones. This could be related to the method of assessment of asbestos exposure as asbestos remains to be the main contributor to the development of MM.