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Asbestblootstelling verhoogt het risico op longkanker. Amfibool-asbestsoorten en verwerking door raffinage geven daarbovenop een extra risico. Er zijn situaties gevonden waarin beroepsmatige blootstelling aan chrysotiel (wit) asbest geen aanwijsbaar risico op longkanker gaf. Bron: Berry, G., Gibbs, G.W., (2007) An overview of the risk of lung cancer in relation to exposure to asbestos and of taconite miners. Regul. Toxicol. Pharmacol., doi:10.1016/j.yrtph.2007.09.012.

Berry, G., Gibbs, G.W., (2007) An overview of the risk of lung cancer in relation to exposure to asbestos and of taconite miners. Regul. Toxicol. Pharmacol., doi:10.1016/j.yrtph.2007.09.012.

Abstract
Exposure&ndash.response relationships between the relative risk of lung cancer and quantitative measures of exposure to asbestos are available from a number of epidemiological studies. Meta-analyses of these relationships have been published by Lash et al. (1997) [Lash, T.L., Crouch, E.A.C., Green, L.C., 1997. A meta-analysis of the relation between cumulative exposure to asbestos and relative risk of lung cancer. Occup. Environ. Med. 54, 254&ndash.263] and Hodgson and Darnton (2000) [Hodgson, J.T., Darnton, A., 2000. The quantitative risks of mesothelioma and lung cancer in relation to asbestos exposure. Ann. Occup. Hyg. 44, 565&ndash.601]. In this paper, the risks derived in these meta-analyses have been compared. Lash et al., concentrated on process and found that the risk of lung cancer increased as the asbestos is refined by processing. Hodgson and Darnton concentrated on fibre type and found that the risk was highest for exposure to amphibole asbestos (crocidolite and amosite), lowest for chrysotile and intermediate for mixed exposure. Some of the differences
between the conclusions from the two meta-analyses are a consequence of the choice of studies included. The range of asbestos types included in the studies in the analysis of Hodgson and Darnton was wider than that in Lash et al., enabling differences between fibre types to be analyzed more readily. There are situations where occupational exposure to chrysotile asbestos has shown no detectable increase in risk of lung cancer. Taconite miners have shown no increased risk of mortality due to lung cancer.

Volgens een overzichtsstudie geeft blootstelling aan de amfibool-asbestsoorten crocidoliet en tremoliet het hoogste risico op de ziekte mesothelioom. Het lijkt erop dat contact met chrysotiel (wit) asbest in pure vorm een zeer laag of nihil risico geeft op deze ziekte. Het verschil in schadelijkheid heeft vooral te maken met de lengte van de asbestvezels. Bron: Gibbs, G.W., Berry, G., (2007) Mesothelioma and asbestos, Regul. Toxicol. Pharmacol. (2007),doi:10.1016/j.yrtph.2007.10.003.

Gibbs, G.W., Berry, G., (2007) Mesothelioma and asbestos, Regul. Toxicol. Pharmacol. (2007),doi:10.1016/j.yrtph.2007.10.003.

Abstract
The current state of knowledge concerning mesothelioma risk estimates is reviewed. Estimates of the risk of mesothelioma exist for the commercial asbestos fiber types chrysotile, amosite and crocidolite. Data also exist on which to assess risks for winchite (sodic tremolite) and anthophyllite asbestos. Uncertainty in estimates is primarily related to limitations in measurements of exposure. Differences in the dimensions of the various fiber types and of the same fiber types at different stages of processing add a further complication. Nevertheless, in practical terms, crocidolite presents the highest asbestos related mesothelioma risk. The risk associated with sodic tremolite (winchite) appears to be similar.
In chrysotile miners and millers, the mesothelioma risk has been linked with exposure to asbestiform tremolite. Exposure to chrysotile in a pure form seems likely to present a very low if any risk of mesothelioma. While the majority of mesothelial tumors result from exposure to the asbestos minerals, there are other well established and suspected etiological agents.
While a practical threshold seems to exist for exposure to chrysotile, it is unlikely to exist for the amphibole asbestos minerals, especially for crocidolite. To date there is no indication of an increased risk of mesothelioma resulting from non-commercial fiber exposure in the taconite industry.

Blootstelling aan asbest kan schade aanrichten aan het immuunsysteem en dat kan leiden tot auto-immuunziekten zoals bijvoorbeeld reuma. Otsuki et al. beschrijven wat er in het lichaam gebeurt na het asbestcontact. Bron: Otsuki, T. (2007) et al. Immunological Effects of Silica and Asbestos. Cellular &amp. Molecular Immunology. 2007.4(4):261-268.

Otsuki, T. (2007) et al. Immunological Effects of Silica and Asbestos. Cellular &amp. Molecular Immunology. 2007.4(4):261-268.
Abstract
Silicosis patients (SILs) and patients who have been exposed to asbestos develop not only respiratory diseases but also certain immunological disorders. In particular, SIL sometimes complicates autoimmune diseases such as systemic scleroderma, rheumatoid arthritis (known as Caplan syndrome), and systemic lupus erythematoses. In addition, malignant complications such as lung cancer and malignant mesothelioma often occurr in patients exposed to asbestos, and may be involved in the reduction of tumor immunity. Although silica-induced disorders of autoimmunity have been explained as adjuvant-type effects of silica, more precise analyses are needed and should reflect the recent progress in immunomolecular findings. A brief summary of our investigations related to the immunological effects of silica/asbestos is presented. Recent advances in immunomolecular studies led to detailed analyses of the immunological effects of asbestos and silica. Both affect immuno-competent cells and these effects may be associated with the pathophysiological development of complications in silicosis and asbestos-exposed patients such as the occurrence of autoimmune disorders and malignant tumors, respectively. In addition, immunological analyses may lead to the development of new clinical tools for the modification of the pathophysiological aspects of diseases such as the regulation of autoimmunity or tumor immunity using cellmediated therapies, various cytokines, and molecule-targeting therapies. In particular, as the incidence of asbestosrelated malignancies is increasing and such malignancies have been a medical and social problem since the summer of 2005 in Japan, efforts should be focused on developing a cure for these diseases to eliminate nationwide anxiety.

Een lage dosis spiraal-CT scan (low-dose computed tomography screening) kan helpen bij het in een vroeg stadium ontdekken van longkanker bij mensen die met asbest hebben gewerkt. Bij de ziekte mesothelioom is de werking van deze techniek nog niet duidelijk. Computertomografie is onderzoek waarbij met r&öntgenstralen zeer gedetailleerde dwarsdoorsnedes van het lichaam zichtbaar gemaakt worden op een beeldscherm. Bron: Fasola, G., et al., (2007). Low-dose computed tomography screening for lung cancer and pleural mesothelioma in an asbestos-exposed population. The Oncologist 12, 1215-1224.

Fasola, G., et al., (2007). Low-dose computed tomography screening for lung cancer and pleural mesothelioma in an asbestos-exposed population: baseline results of a prospective, nonrandomized feasibility trial–an Alpe-adria Thoracic Oncology Multidisciplinary Group Study (ATOM 002). The Oncologist 12, 1215-1224.
ABSTRACT
OBJECTIVE: To evaluate the feasibility of using low-dose computed tomography (LDCT) for the early diagnosis of lung cancer and malignant pleural mesothelioma in an asbestos-exposed population.

METHODS: Between February 2002 and October 2003, 1,045 volunteers already enrolled in a surveillance program for asbestos-exposed workers and former workers were recruited. The main eligibility criteria were: written informed consent, definite exposure to asbestos, age 40-75, no prior cancer or severe concomitant conditions, no chest CT scan in the past 2 years. A smoking history was not required. After a structured interview, chest X-ray (CXR) and LDCT were performed. Participants with negative examinations were assigned to annual LDCT. Participants with positive findings received high-resolution CT and additional diagnostic workup as appropriate.

RESULTS: Baseline characteristics of the screened population were: median asbestos exposure time, 30 years. median age, 58. median pack-years in smokers/former smokers, 18.5. Thirty-four percent had never smoked. On LDCT, 834 noncalcified nodules were identified in 44% of participants, versus 43 nodules in 4% on CXR. Pleural abnormalities were observed in 44% and 70% of participants by CXR and LDCT, respectively. Overall, LDCT identified nine cases of non-small cell lung cancer-eight stage I, one stage IIA-and one thymic carcinoid, corresponding to 1% of the enrolled population. All cases were radically treated. None had been detected by CXR. No pleural mesothelioma was diagnosed. There were 11 false-positive results.

CONCLUSIONS: Our findings first suggest that LDCT may be at least as useful in asbestos workers as in heavy smokers for the early diagnosis of lung cancer. this benefit is evident even in a poor-risk population, with low rates of smoking prevalence and a previous history of radiological surveillance. The role of spiral tomography in screening for pleural mesothelioma remains uncertain.

52 amerikaanse wetenschappers hebben verklaard dat chrysotiel asbest in remvoeringen mesothelioom kan veroorzaken. Zij stellen dat ook kortdurende en lage niveaus van asbestblootstelling mesothelioom kunnen veroorzaken. In de wetenschappelijke literatuur komen honderden gevallen van mesothelioom onder automonteurs voor. De verklaring is een reactie op de verdediging die de Amerikaanse auto-industrie voert bij het Hooggerechtshof van Michigan. Men probeert daar aan te tonen dat het aangevoerde bewijs voor mesothelioom door chrysotiel asbest in remvoeringen wetenschappelijk ondeugdelijk is (“junk science”. Bron: Welch, L.S. et al., (2007). Asbestos Exposure Causes Mesothelioma, But Not This Asbestos Exposure: An Amicus Brief to the Michigan Supreme Court. International Journal of Occupational Environmental Health.13:318-327.

Welch, L.S. et al., (2007). Asbestos Exposure Causes Mesothelioma, But Not This Asbestos Exposure: An Amicus Brief to the Michigan Supreme Court. International Journal of Occupational Environmental Health.13:318-327.
Abstract
Manufacturers of asbestos brakes, supported by many manufacturing and insurance industry amicus curie, requested the Michigan Supreme Court to dismiss testimony of an expert regarding the ability of asbestos dust from brakes to cause mesothelioma as “junk science” Scientists are concerned with the sweeping and unequivocal claims that any conclusion that asbestos from brakes caused a signature asbestos-related disease in a particular person must be “junk science.” The manufacturers” sweeping pronouncements are what veer
from accepted, reliable mainstream scientific methods and conclusions. This article outlines the evidence supporting the conclusion that asbestos from brakes can and does cause mesothelioma, and describes the defendants” attempts to fabricate doubt about this conclusion.

Franse huisartsen zien bij rokende longkankerpatiënten nogal eens over het hoofd dat asbestblootstelling een rol kan hebben gespeeld bij het ontstaan van de ziekte. Franse longartsen zijn daar echter wel alert op. Bron: Verger, P. et al. (2007). Inequities in reporting asbestos-related lung cancer: influence of smoking stigma and physician’s, specialty, workload, and role perception. OEM online, 10 okt 2007, doi:10.1136/oem.2007.035808.

Verger, P. et al. (2007). Inequities in reporting asbestos-related lung cancer: influence of smoking stigma and physician’s, specialty, workload, and role perception. OEM online, 10 okt 2007, doi:10.1136/oem.2007.035808.
Abstract:
Objectives: To study physician barriers to workers&rsquo. compensation claims for asbestos-related cancers, focusing on smokers&rsquo. stigma and physicians&rsquo. speciality and role perception.
Methods: Cross-sectional telephone study of 486 randomly-selected physicians: general practitioners (GPs) and pulmonologists in southeastern France. Standardised questionnaires explored their behaviour, attitudes and practices in the field of occupational health and their responses to a case-vignette about a lung cancer patient with long-term occupational asbestos exposure. Randomised subgroups of GPs and pulmonologists heard alternative versions
varying only in the worker&rsquo.s smoking status. We studied factors associated with the recommendation that the case-vignette patient file a compensation claim with simple and multiple logistic regressions.
Results: The response rate was 64.4% among GPs and 62.5% among pulmonologists. Recommending the filing of an occupational disease claim was significantly associated in multiple logistic regressions with speciality (OR=4.46. 95%CI=2.38-8.37, for pulmonologists versus GPs), patient&rsquo.s smoking status (OR=3.15. 95%CI=2.11-4.70, for non-smokers versus smokers), physician&rsquo.s workload (OR=1.83. 95%CI= 1.17-2.88, for &le.25 consultations per day versus &gt.25), and role perception (OR=2.00. 95%CI=1.22-3.27, for those who considered completing occupational disease medical certificates to be part of their role versus those who did not).
Conclusions: The results of this French study appear applicable to various countries and contexts. To make physicians and especially GPs more aware of occupational health and smoking stigma, officials and educators must give these topics higher priority during initial training and continuing medical education. Tools and equipment that take time constraints into account.

Het vaker voorkomen van de ziekte mesothelioom in bepaalde families ligt vooral aan gemeenschappelijke bronnen van asbestblootstelling. Daarnaast zouden echter ook erfelijke factoren een rol kunnen spelen. Dit concluderen Italiaanse onderzoekers na analyse van 20 studies die rapporteren over het voorkomen van deze ziekte in bepaalde families. Ugolini, D., et al., (2007) Genetic susceptibility to malignant mesothelioma and exposure to asbestos: The influence of the familial factor. Mutat. Res.: Rev. Mutat. Res. (2007), doi:10.1016/j.mrrev.2007.08.001.

Ugolini, D., et al., (2007) Genetic susceptibility to malignant mesothelioma and exposure to asbestos: The influence of the familial factor. Mutat. Res.: Rev. Mutat. Res. (2007), doi:10.1016/j.mrrev.2007.08.001.
Abstract
Background: Asbestos is the principal etiological factor of malignant mesothelioma (MM), accounting for more than 80% of all
tumor cases. However, other co-factors, including genetic susceptibility may play a role in the etiology of this disease, possibly modulating the effects of exposure to asbestos and other carcinogenic mineral fibers. The frequent report of familial clustering was the first indication supporting the involvement of genetic factors. Therefore, we performed an extensive literature search to evaluate existing studies reporting familial cases of MM.
Methods: Published reports addressing the issue of familial susceptibility to MM have been searched through PubMed using
keywords and free text tools. Eighty-two citations were retrieved and 20 of them actually reported a familial cluster of MM. Three
more articles were identified through the references. The probability that the observed familial clusters of mesothelioma could have
randomly occurred in exposed families was evaluated with the Family History Score Zi (FHSi).
Results: The result of this analysis suggested that clustering ofMMcases in families exposed to asbestos may be explained with the additional contribution of other familial factors. The FHSi allowed to reject the hypothesis of random occurrence of these clusters with a probability of a first type error ranging between 1 per cent and 1 per billion.
Conclusions: The evaluation of the published materials supports the hypothesis that &ndash. although familial clustering ofMMis largely
attributable to shared asbestos exposure &ndash. the additional contribution of factors dealing with genetic susceptibility may play a role in the etiology of MM.

Factoren die een aanwijzing kunnen geven over de levensverwachting van mesothelioompatiënten zijn: het soort mesothelioom, de locatie van de tumor in het lichaam, sekse, rookgedrag en de conditie en symptomen van de patiënt. Een Behandeling met een combinatie van chemo-, radiotherapie en operatieve verwijdering van de tumor lijkt het best te werken, hoewel meer onderzoek nodig is. Dit concluderen Amerikaanse onderzoekers na analyse van medische gegevens van 945 patiënten die tussen 1990 en 2005 in een New Yorks ziekenhuis voor mesothelioom waren behandeld. Flores, R.M. et al., (2007). Prognostic Factors in the Treatment of Malignant Pleural Mesothelioma at a Large Tertiary Referral Center. Journal of Thoracic Oncology, 2, oct. 2007, p. 957-965.

Flores, R.M. et al., (2007). Prognostic Factors in the Treatment of Malignant Pleural Mesothelioma at a Large Tertiary Referral Center. Journal of Thoracic Oncology, 2, oct. 2007, p. 957-965.
Abstract:
Introduction: Most studies describing the natural history and prognostic factors for malignant pleural mesothelioma antedate accurate pathologic diagnosis, staging by computed tomography, and a universal staging system. We conducted a large single-institution analysis to identify prognostic factors and assess the association of resection with outcome in a contemporary patient population.
Methods: Patients with biopsy-proven malignant pleural mesothelioma at our institution were identified and clinical data were obtained from an institutional database. Survival and prognostic factors were analyzed by the Kaplan-Meier method, log-rank test, and Cox proportional hazards analysis. A p value &lt. 0.05 was considered statistically significant.
Results: From 1990 to 2005, 945 patients were identified: 755 men, 190 women. median age, 66 years (range, 26&ndash.93). Extrapleural pneumonectomy was performed in 208 (22%), pleurectomy/decortication in 176 (19%). Operative mortality was 4% (16/384). Multimodality therapy including surgery was associated with a median survival of 20.1 months. Significant predictors of overall survival included histology, gender, smoking, asbestos exposure, laterality, surgical resection by extrapleural pneumonectomy or pleurectomy/decortication, American Joint Committee on Cancer stage, and symptoms. A Cox model demonstrated a hazard ratio of 1.4 without surgical resection when controlling for histology, stage, gender, asbestos exposure, smoking history, symptoms, and laterality (p = 0.003).
Conclusions: In addition to tumor histology and pathologic stage,
predictors of survival include gender, asbestos exposure, smoking,
symptoms, laterality, and clinical stage. Surgical resection in a
multimodality setting was associated with improved survival.

Biochemicus Peter Duesburg stelt dat schade aan chromosomen de directe oorzaak is van het ontstaan van kanker en niet een bij-effect van de versnelde celdeling. Dat geldt vooral voor kankersoorten die door gevaarlijke stoffen als asbest ontstaan. De menselijke cel bevat 40.000 genen die in 23 verschillende groepen zijn verdeeld, genaamd chromosomen. Bron: The Irish Times, 16 augustus 2007.

Finse onderzoekers constateerden dat aan asbest blootgestelde bouwvakkers die in herfst of winter geboren zijn relatief vaker fibrose aan de longen hebben dan degenen die in lente of zomer geboren zijn. Een mogelijke verklaring is dat herfst- en winterkinderen vlak na de geboorte vaker infecties aan de luchtwegen hebben die hen gevoeliger maken voor de effecten van asbestvezels later in hun leven. Bron: Hannu, T. et al., (2007). Season of birth and lung fibrosis among workers exposed to asbestos. Chronobiology Intenational 24(3):539-552.
Hannu, T. et al., (2007). Season of birth and lung fibrosis among workers exposed to asbestos. Chronobiology Intenational 24(3):539-552.
The season of birth has been suggested to influence the development of some diseases, but its role in lung fibrosis seems to not have been studied previously. The aim of this study was to investigate the relation between the season of birth and fibrotic abnormalities as detected radiologically in high-resolution computed tomography (HRCT) among workers exposed to asbestos. The HRCT examination was performed on 528 study subjects. Multiple ordinal regression analysis adjusting for covariates was used to study the relations between birth month or season and radiological fibrosis signs. Subjects born in autumn or winter had more extensive fibrotic changes than those born in spring or summer. This applied to all fibrotic changes, apart from subpleural nodules, but only the overall fibrosis score, septal lines, and honeycombing showed statistically significantly higher values in comparison to spring births. The highest scores were detected among those born in autumn and winter months (September-February). These results suggest that there are differences in fibrotic radiological abnormalities according to the season of birth in adults exposed to asbestos. Several hypotheses could explain the observed findings, including the effects of early respiratory infections, cold temperature, and differences in air pollution levels, as well as some metabolic and hormonal effects.