Comments on the Causation of Malignant Mesothelioma: Rebutting the False Concept That Recent Exposures to Asbestos Do Not Contribute to Causation of Mesothelioma

Background: European asbestos manufacturers and their expert witnesses have advanced the claim that recent exposures to asbestos are not of significance in the causation of malignant mesothelioma. They argue that in cases of prolonged exposure to asbestos only the earliest exposures contribute to mesothelioma induction. Methods: The Collegium Ramazzini examined this claim and compared it with the findings of the Epidemiology and Public Health Working Group of the Second Italian Consensus Conference on Pleural Mesothelioma. This independent Working Group noted that earlier exposures are more effective in inducing mesothelioma, but that subsequent exposures also contribute and cannot be excluded. They found convincing evidence to support the conclusion that mesothelioma incidence is proportional to cumulative asbestos exposure. Conclusion: The Collegium Ramazzini concludes that risk of malignant mesothelioma is proportional to cumulative exposure to asbestos in which all exposures - early as well as late - contribute to the totality of risk. The Collegium Ramazzini rejects as false and scientifically unfounded the notion that only the earliest exposures to asbestos contribute to mesothelioma induction

Arretium or Arezzo? A Neural Approach to the Identification of Place Names in Historical Texts

This paper presents the application of a neural architecture to the identification of place names in English historical texts. We test the impact of different word embeddings and we compare the results to the ones obtained with the Stanford NER module of CoreNLP before and after the retraining using a novel corpus of manually annotated historical travel writings

Letter

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The epidemiology of malignant mesothelioma in women: gender differences and modalities of asbestos exposure

INTRODUCTION: The epidemiology of gender differences for mesothelioma incidence has been rarely discussed in national case lists. In Italy an epidemiological surveillance system (ReNaM) is working by the means of a national register. METHODS: Incident malignant mesothelioma (MM) cases in the period 1993 to 2012 were retrieved from ReNaM. Gender ratio by age class, period of diagnosis, diagnostic certainty, morphology and modalities of asbestos exposure has been analysed using exact tests for proportion. Economic activity sectors, jobs and territorial distribution of mesothelioma cases in women have been described and discussed. To perform international comparative analyses, the gender ratio of mesothelioma deaths was calculated by country from the WHO database and the correlation with the mortality rates estimated. RESULTS: In the period of study a case list of 21 463 MMs has been registered and the modalities of asbestos exposure have been investigated for 16 458 (76.7%) of them. The gender ratio (F/M) was 0.38 and 0.70 (0.14 and 0.30 for occupationally exposed subjects only) for pleural and peritoneal cases respectively. Occupational exposures for female MM cases occurred in the chemical and plastic industry, and mainly in the non-asbestos textile sector. Gender ratio proved to be inversely correlated with mortality rate among countries. CONCLUSIONS: The consistent proportion of mesothelioma cases in women in Italy is mainly due to the relevant role of non-occupational asbestos exposures and the historical presence of the female workforce in several industrial settings. Enhancing the awareness of mesothelioma aetiology in women could support the effectiveness of welfare system and prevention policies

The epidemiology of malignant mesothelioma in women: gender differences and modalities of asbestos exposure

ntroduction The epidemiology of gender differences for mesothelioma incidence has been rarely discussed in national case lists. In Italy an epidemiological surveillance system (ReNaM) is working by the means of a national register. Methods Incident malignant mesothelioma (MM) cases in the period 1993 to 2012 were retrieved from ReNaM. Gender ratio by age class, period of diagnosis, diagnostic certainty, morphology and modalities of asbestos exposure has been analysed using exact tests for proportion. Economic activity sectors, jobs and territorial distribution of mesothelioma cases in women have been described and discussed. To perform international comparative analyses, the gender ratio of mesothelioma deaths was calculated by country from the WHO database and the correlation with the mortality rates estimated. Results In the period of study a case list of 21 463 MMs has been registered and the modalities of asbestos exposure have been investigated for 16 458 (76.7%) of them. The gender ratio (F/M) was 0.38 and 0.70 (0.14 and 0.30 for occupationally exposed subjects only) for pleural and peritoneal cases respectively. Occupational exposures for female MM cases occurred in the chemical and plastic industry, and mainly in the non-asbestos textile sector. Gender ratio proved to be inversely correlated with mortality rate among countries. Conclusions The consistent proportion of mesothelioma cases in women in Italy is mainly due to the relevant role of non-occupational asbestos exposures and the historical presence of the female workforce in several industrial settings. Enhancing the awareness of mesothelioma aetiology in women could support the effectiveness of welfare system and prevention policie

Comments on: Further studies of Bolivian crocidolite-Part IV: Fibre width, fibre drift and their relation to mesothelioma induction: Preliminary findings, by Ilgren EB, van Orden DR, Lee RJ, Kamiya YM, Hoskins JA

Comments on: Further studies of Bolivian crocidolite-Part IV: Fibre width, fibre drift and their relation to mesothelioma induction: Preliminary findings, by Ilgren EB, van Orden DR, Lee RJ, Kamiya YM, Hoskins JA

Letter concerning:‘Response to:‘The epidemiology of malignant mesothelioma in women: gender differences and modalities of asbestos exposure’by Marinaccio et al’

Finkelstein1 invited physicians and researchers interested in mesothelioma to investigate on past usage of talcum powders by affected people. In Italy, asbestos contamination in talc for industrial use has been documented,2 and, as he underlines tremolite contamination at low levels of cosmetic and pharmaceutical talc has been reported in USA by Blount3 and Gordon and colleagues.4 In the Italian National Mesothelioma Register (ReNaM), the analysis of intensive exposure to talc has been evaluated with respect to occupational and environmental history. The catalogue of possible asbestos exposure circumstances (a tool for the interviewers) reports the potential presence of industrial talcs in quarries or mines working activities, in leather tanning and in rubber industries. The use of intensive cosmetic talc for personal use is evaluated by means of a structured questionnaire,5 as reported in the ReNaM guidelines (see https://www.inail.it/cs/internet/docs/all-linee-guida-renam.pdf?section=attivita, p82, p98, in Italian). In our paper regarding gender differences in mesothelioma epidemiology,6 we have presented figures referring to 21 463 MM cases detected by ReNaM with a diagnosis between 1993 and 2012. Among female case list (6087 cases), 4374 cases (71.9%) have been interviewed for defining exposure. During the interview, 30 MM female cases referred an intensive use of talc in the context of occupational or life habits. For five of them, the regional centre has identified an exposure to asbestos due to intensive talc use, classifying such modality of exposure as ‘leisure activities’ (see ReNaM guidelines5). For the remaining 25 cases, an occupational exposure to asbestos in other working (or familiar or environmental) circumstances has been identified and coded. Registry data such as those provided by ReNaM cannot provide estimates of the mesothelioma risk associated with any particular exposure circumstance. We plan to include talc exposure at work and cosmetic talc usage in the analyses of a case–control study on pleural mesothelioma currently under way. A specific survey to compare and discuss how the modalities of exposure to talc have been evaluated in patients with mesothelioma in countries where epidemiological surveillance systems are active could improve knowledge and support prevention policies

La prevención de las patologías del asbesto: perspectivas operativas de la cooperación italiana con los países de américa latina

El propósito del presente artículo es valorar la tesis de que el impacto en la salud de la exposición a fibras de asbesto presentes en los lugares de trabajo y en el ambiente, requiere contramedidas basadas en la evidencia científica y la cooperación internacional. La evidencia científica adquirida en el ámbito internacional sobre el asbesto, la experiencia pluridecenal madurada en Italia sobre este tema, así como la conciencia de que la adopción de medidas para combatir los efectos en la salud causados por la exposición a asbesto, deben ser verificadas considerando la especificidad de los diversos contextos nacionales y locales en América Latina. Constituyen la base para la identificación de las cuatro principales directrices de intervención (Promoción del acceso a la documentación sobre el asbesto; Realización de intervenciones para reducir la exposición al asbesto; Vigilancia sanitaria de los sujetos expuestos; Detección del mesotelioma) que pueden ser desarrolladas en el ámbito de la cooperación técnico-científica entre Italia y los países de América Latina. La integración de las capacidades de los investigadores colombianos e italianos permitirá obtener estos resultados, contribuyendo al proceso de eliminación del asbesto, ya en curso en América Latin

Authors' response: Mezei et al's "Comments on a recent case-control study of malignant mesothelioma of the pericardium and the tunica vaginalis testis"

: Mezei et al's letter (1) is an opportunity to provide more details about our study on pericardial and tunica vaginalis testis (TVT) mesothelioma (2), which is based on the Italian national mesothelioma registry (ReNaM): a surveillance system on mesothelioma, with individual asbestos exposure assessment. Incidence of pericardial mesothelioma has been estimated around 0.5 and 0.2 cases per 10 million person-years in men and women, respectively, and around 1 case for TVT mesothelioma. ReNaM collected 138 cases thanks to its long period of observation (1993-2015) and national coverage. Conducting a population-based case-control study with incidence-density sampling of controls across Italy and over a 23 year time-span should have been planned in 1993 and would have been beyond feasibility and ReNaM scope. We rather exploited two existing series of controls (3). The resulting incomplete time- and spatial matching of cases and controls is a limitation of our study and has been acknowledged in our article. The analysis of case-control studies can nevertheless be accomplished in logistic models accounting for the variables of interest, in both individually and frequency matched studies (4). Furthermore, analyses restricted to (i) regions with enrolled controls, (ii) cases with definite diagnosis, (iii) incidence period 2000-2015, and (iv) subjects born before 1950 have been provided in the manuscript, confirming the strength of the association with asbestos exposure (supplemental material tables S4-7). Following Mezei et al's suggestion, we performed further sensitivity analyses by restriction to regions with controls and fitting conditional regression models using risk-sets made of combinations of age and year of birth categories (5-year classes for both). We confirmed positive associations with occupational exposure to asbestos of pericardial mesothelioma, with odds ratios (OR) (adjusted for region) of 9.16 among women [95% confidence interval (CI) 0.56-150] and 5.63 (95% CI 1.02-31.0) among men; for TVT mesothelioma the OR was 7.70 (95% CI 2.89-20.5). Using risk sets of age categories and introducing year of birth (5-year categories) as a covariate (dummy variables) the OR were similar: OR (adjusted for region) of 9.17 among women (95% CI 0.56-150) and 5.76 (95% CI 1.07-31.0) among men; for TVT the OR was 9.86 (95% CI 3.46-28.1). Possible bias from incomplete geographical overlap between cases and controls has been addressed in the paper (table S4) and above. In spatially restricted analyses, OR were larger than in those including cases from the whole country, indicating that bias was towards the null. Mezei et al further noted that "the regional distribution of controls is different from that of person-time observed". This objection is not relevant because the above analyses were adjusted by region. Our controls were provided by a population-based study on pleural mesothelioma (called MISEM) and a hospital-based study on cholangiocarcinoma (called CARA). In MISEM, the response rate was 48.4%, a low but not unexpected rate as participation among population controls is usually lower and has been declining over time (5). It is important to underline that ReNaM applied the same questionnaire that was used for interviews and carried out the same exposure assessment as both MISEM and CARA. As repeatedly stated in ReNaM papers (6-7), each regional operating center assesses asbestos exposure based on the individual questionnaire, other available information, and knowledge of local industries. Occupational exposure to asbestos is classified as definite, probable or possible. Occupational exposure is (i) definite when the subject`s work was reported or otherwise known to have involved the use of asbestos or asbestos-containing materials (MCA); (ii) probable when subjects worked in factories where asbestos or MCA were used, but their personal exposure could not be documented; and (iii) possible when they were employed in industrial activities known to entail the use of asbestos or MCA. Hence, the definite and probable categories are closer to one another and were combined in our analyses. In any case, restricting analyses to subjects with definite occupational exposure and using each set of controls separately, as suggested by Mezei et al, yielded elevated OR for TVT and pericardial mesothelioma among men using both the above described modelling strategies; the OR could not be calculated for women. There were 70 (25 pericardial and 45 TVT) occupationally exposed mesothelioma cases. In population-based studies, analyses by occupation are limited by the low prevalence of most specific jobs. As briefly reported in our paper, for purely descriptive purposes, the industrial activity of exposure (cases may have multiple exposures), were construction (22 exposures, 7 and 15 for pericardial and TVT mesotheliomas, respectively), steel mills and other metal working industries (4 and 11), textile industries (2 and 3), and agriculture (2 and 5); other sectors had lower exposure frequencies. The absence of industries like asbestos-cement production, shipbuilding and railway carriages production/repair should not be surprising and had already been observed (7). In the Italian multicenter cohort study of asbestos workers (8), given the person-years of observation accrued by workers employed in these industries and gender- and site-specific crude incidence rates, approximately 0.1 case of pericardial and 0.2 of TVT mesothelioma would have been expected from 1970 to 2010. Even increasing ten-fold such figures to account for higher occupational risks among these workers would not change much. Asbestos exposure in agriculture has been repeatedly discussed in ReNaM reports (9: pages 70, 73, 128, 164 and 205). Exposure opportunities included the presence of asbestos in wine production, reuse of hessian bags previously containing asbestos, or construction and maintenance of rural buildings. Similarly, mesothelioma cases and agricultural workers exposed to asbestos have been noted in France (10). In conclusion, the additional analyses we performed according to Mezei et al's suggestions confirm the association between asbestos exposure and pericardial and TVT mesothelioma, supporting the causal role of asbestos for all mesotheliomas. ReNaM`s continuing surveillance system with national coverage is a precious platform for launching analytical studies on pleural and extra pleural mesothelioma. References 1. Mezei G, Chang ET, Mowat FS, Moolgavkar SH. Comments on a recent case-control study of malignant mesothelioma of the pericardium and the tunica vaginalis testis Scand J Work Environ Health. 2021;47(1):85-86. https://doi.org/10.5271/3909 2. Marinaccio A, Consonni D, Mensi C, Mirabelli D, Migliore E, Magnani C et al.; ReNaM Working Group. Association between asbestos exposure and pericardial and tunica vaginalis testis malignant mesothelioma: a case-control study and epidemiological remarks. Scand J Work Environ Health. 2020;46(6):609-617. https://doi.org/10.5271/sjweh.3895. 3. Greenland S. Control-initiated case-control studies. Int J Epidemiol 1985 Mar;14(1):130-4. https://doi.org/10.1093/ije/14.1.130. 4. Pearce N. Analysis of matched case-control studies. BMJ 2016 Feb;352:i969. https://doi.org/10.1136/bmj.i969. 5. Bigert C, Gustavsson P, Straif K, Pesch B, Brüning T, Kendzia B et al. Lung cancer risk among cooks when accounting for tobacco smoking: a pooled analysis of case-control studies from Europe, Canada, New Zealand, and China. J Occup Environ Med 2015 Feb;57(2):202-9. https://doi.org/10.1097/JOM.0000000000000337. 6. Marinaccio A, Binazzi A, Marzio DD, Scarselli A, Verardo M, Mirabelli D et al.; ReNaM Working Group. Pleural malignant mesothelioma epidemic: incidence, modalities of asbestos exposure and occupations involved from the Italian National Register. Int J Cancer 2012 May;130(9):2146-54. https://doi.org/10.1002/ijc.26229. 7. Marinaccio A, Binazzi A, Di Marzio D, Scarselli A, Verardo M, Mirabelli D et al. Incidence of extrapleural malignant mesothelioma and asbestos exposure, from the Italian national register. Occup Environ Med 2010 Nov;67(11):760-5. https://doi.org/10.1136/oem.2009.051466. 8. Ferrante D, Chellini E, Merler E, Pavone V, Silvestri S, Miligi L et al.; the working group. Italian pool of asbestos workers cohorts: mortality trends of asbestos-related neoplasms after long time since first exposure. Occup Environ Med 2017 Dec;74(12):887-98. https://doi.org/10.1136/oemed-2016-104100. 9. ReNaM VI Report. Available from: https://www.inail.it/cs/internet/docs/alg-pubbl-registro-nazionale-mesoteliomi-6-rapporto.pdf. Italian 10. Marant Micallef C, Shield KD, Vignat J, Baldi I, Charbotel B, Fervers B et al. Cancers in France in 2015 attributable to occupational exposures. Int J Hyg Environ Health 2019 Jan;222(1):22-9. https://doi.org/10.1016/j.ijheh.2018.07.015