Cause specific mortality in an Italian pool of asbestos workers cohorts.

BACKGROUND: Asbestos is a known human carcinogen and is causally associated with malignant mesothelioma, lung, larynx and ovarian cancers. METHODS: Cancer risk was studied among a pool of formerly asbestos-exposed workers in Italy. Fifty-two Italian asbestos cohorts (asbestos-cement, rolling-stock, shipbuilding, and other) were pooled and their mortality follow-up was updated to 2018. Standardized mortality ratios (SMRs) were computed for major causes of death considering duration of exposure and time since first exposure (TSFE), using reference rates by region, age and calendar period. RESULTS: The study included 63,502 subjects (57,156 men and 6346 women): 40% who were alive, 58% who died (cause known for 92%), and 2% lost to follow-up. Mortality was increased for all causes (SMR: men = 1.04, 95% confidence interval [CI] 1.03-1.05; women = 1.15, 95% CI 1.11-1.18), all malignancies (SMR: men = 1.21, 95% CI 1.18-1.23; women = 1.29, 95% CI 1.22-1.37), pleural and peritoneal malignancies (men: SMR = 10.46, 95% CI 9.86-11.09 and 4.29, 95% CI 3.66-5.00; women: SMR = 27.13, 95% CI 23.29-31.42 and 7.51, 95% CI 5.52-9.98), lung (SMR: men = 1.28, 95% CI 1.24-1.32; women = 1.26, 95% CI 1.02-1.53), and ovarian cancer (SMR = 1.42, 95% CI 1.08-1.84). Pleural cancer mortality increased during the first 40 years of TSFE (latency), reaching a plateau thereafter. CONCLUSIONS: Analyses by time-dependent variables showed that the risk for pleural neoplasms increased with latency and no longer increases at long TSFE, consistent with with asbestos clearance from the lungs. Peritoneal neoplasm risk increased over all observation time.

Incidence of mesothelioma in young people and causal exposure to asbestos in the Italian national mesothelioma registry (ReNaM).

INTRODUCTION: The epidemiological surveillance of mesothelioma incidence is a crucial key for investigating the occupational and environmental sources of asbestos exposure. The median age at diagnosis is generally high, according to the long latency of the disease. The purposes of this study are to analyse the incidence of mesothelioma in young people and to evaluate the modalities of asbestos exposure. METHODS: Incident malignant mesothelioma (MM) cases in the period 1993-2018 were retrieved from Italian national mesothelioma registry and analysed for gender, incidence period, morphology and exposure. Age-standardised rates have been calculated and the multiple correspondence analysis has been performed. The association between age and asbestos exposure has been tested by χ2 test. RESULTS: From 1993 to 2018, 30 828 incident MM cases have been collected and 1278 (4.1%) presented diagnosis at early age (≤50 years). There is a substantial association between age at diagnosis and the type of asbestos exposure and a significantly lower frequency of cases with occupational exposure to asbestos (497 cases vs 701 expected) in young people has been documented. Paraoccupational and environmental exposure to asbestos have been found more frequent in young MM cases (85 and 93 observed cases vs 52 and 44 expected cases, respectively). CONCLUSIONS: Mesothelioma incidence surveillance at population level and the anamnestic individual research of asbestos exposure is a fundamental tool for monitoring asbestos exposure health effects, supporting the exposure risks prevention policies. Clusters of mesothelioma incident cases in young people are a significant signal of a potential non-occupational exposure to asbestos.

Mesothelioma Risk among Construction Workers According to Job Title: Data from the Italian Mesothelioma Register.

BACKGROUND: An increased risk of mesothelioma has been reported in various countries for construction workers. The Italian National Mesothelioma Registry, from 1993 to 2018, reported exposure exclusively in the construction sector in 2310 cases. We describe the characteristics of these cases according to job title. METHODS: We converted into 18 groups the original jobs (N=338) as reported by ISTAT codes ('ATECO 91'). The exposure level was attributed at certain, probable and possible in accordance with the qualitative classification of exposure as reported in the Registry guidelines. Descriptive analysis by jobs highlights the total number of subjects for each single job and certain exposure, in descending order, insulator, plumbing, carpenter, mechanic, bricklayer, electrician, machine operator, plasterer, building contractor, painter and labourer. RESULTS: The cases grow for plumbing in the incidence periods 1993-2018, while, as expected, it decreases for insulator. Within each period considered the most numerous cases are always among bricklayers and labourers, these data confirm the prevalence of non-specialised "interchangeable" jobs in Italian construction sector in the past. CONCLUSIONS: Despite the 1992 ban, the construction sector still presents an occupational health prevention challenge, circumstances of exposure to asbestos may still occur due to incomplete compliance with prevention and protection measures.

Mesothelioma Risk Among Maritime Workers According to Job Title: Data From the Italian Mesothelioma Register (ReNaM).

The study describes the 466 cases of malignant mesotheliomas (MM) collected by the National Mesothelioma Register (ReNaM) in Italy in the period 1993-2018 relating to subjects with exclusive asbestos exposure in merchant or military navy. The cases among maritime workers represent 1.8% of the total cases with defined exposure registred in the ReNaM, of which 212 cases (45.4%) among merchant maritime workers and 254 cases (54.5%) among navy. The distribution by site of mesothelioma showed 453 (97.2%) MM cases of the pleura, 11 (2.3%) of the peritoneum and 2 (0.4%) of the tunica vaginalis of the testis. With regard to occupational exposure, it was classified as certain in 318 (68.2%) cases, probable in 69 (14.8%) cases and possible in 79 (16.9%) cases. Among the 23 classified jobs, the highest percentages of certain exposures are among naval engineers, motor mechanics, machine captains and sailors. Machine crew accounted for 49.3% of the cases, deck crew for 27.6%. All cases began exposure on board between 1926 and 1988. Seamen were exposed to asbestos while at sea by virtue of living onboard ships and from continual release of asbestos fibers due to the motion of a vessel. Epidemiological surveillance through the ReNaM has allowed us to verify among cases in the maritime, navy and merchant marine sectors, that in the past, subjects were exposed regardless of the ship's department where have provided service therefore all these cases must be considered as occupational diseases.

[The new national guidelines for the keeping of the Italian Sinonasal Cancer Registry (ReNaTuNS)]. / Il nuovo manuale operativo ReNaTuNS per la gestione dei casi di tumore naso-sinusale.

Sinonasal cancers (SNC) are rare tumours with predominant occupational aetiology associated with exposures to specific carcinogens. In Italy, SNC incidence has been under compulsory surveillance since 2008, through the National Sinonasal Cancer Registry (ReNaTuNS), a nationwide cancer registry coordinated by the National Institute for Insurance Against Accidents at Work (Inail). The ReNaTuNS has a regional structure with local registries, established at Regional Operating Centres (CORs). Currently, seven Italian Regions are active in SNC search and, together with Inail, have recently released a new version of the national guidelines for keeping the Registry (available on the Inail website). The aim of this text is to present the new guidelines, an updating version, and to underline the relevance of this tool in enforcing the role of the ReNaTuNS, considering the high occupational fraction of SNC and the unicity of the Italian Registry, which collects all the information available on occupational exposures of each SNC case registered. It is recommended that the active search for SNC cases and the analysis of exposure become a systematic and well-organized activity to prevent or reduce risks of exposure and to support and improve the efficiency of the compensation and welfare system.

The epidemiological surveillance of malignant mesothelioma in Italy (1993-2015): methods, findings, and research perspectives.

BACKGROUND: as a legacy of the large asbestos consumption until the definitive ban in 1992, Italy had to tackle a real epidemic of asbestos related diseases. The Italian National Registry of Malignant Mesotheliomas (ReNaM) is a permanent surveillance system of mesothelioma incidence, with a regional structure. Aims, assignments and territorial network of ReNaM are described, as well as data collection, recording and coding procedures. OBJECTIVES: to describe the Italian epidemiological surveillance system of mesothelioma incidence, to provide updated data about occurrence of malignant mesothelioma in Italy, and to discuss goals, attainments, and expectations of registering occupational cancer. DESIGN: analysis of data by malignant mesothelioma incident cases surveillance system. SETTING AND PARTICIPANTS: Italy, network of regional surveillance system, all Italian regions. MAIN OUTCOME MEASURES: a Regional Operating Centre (COR) is currently established in all the Italian regions, actively searching incident malignant mesothelioma cases from health care institutions. Occupational history, lifestyle habits, and residential history are obtained using a standardized questionnaire, administered to the subject or to the next of kin by a trained interviewer. The extent of dataset, epidemiological parameters, and occupations involved are reported updated at 31.12.2016, and standardized incidence rates are calculated. RESULTS: at December 2016, ReNaM has collected 27,356 malignant mesothelioma cases, referring to the period of incidence between 1993 and 2015. The modalities of exposure to asbestos have been investigated for 21,387 (78%) and an occupational exposure has been defined for around 70% of defined cases (14,818). CONCLUSIONS: the Italian experience shows that epidemiological systematic surveillance of asbestos related diseases incidence has a key importance for assessing and monitoring the public health impact of occupational and/or environmental hazards, programming preventive interventions, including remediation plans and information campaigns, and supporting the efficiency of insurance and welfare system. Monitoring the incidence of malignant mesothelioma through a specialized cancer registry is essential to follow-up the health effects of changing modalities and extent of occupational exposures over years and of environmental contamination. Such consolidated surveillance system is recommended also for occupational cancers with low aetiological fraction.

[The new ReNaTuNS operating manual for nasal sinus tumor case management].

SUMMARY: No abstract available.

Evaluation of the impact of heat stress on the occurrence of occupational injuries: Meta-analysis of observational studies.

BACKGROUND: Growing evidence indicates that the exposure to high heat levels in the workplace results in health problems in workers. A meta-analysis was carried out to summarize the epidemiological evidence of the effects of heat exposure on the risk of occupational injuries. METHODS: A search strategy was conducted to retrieve studies on the effects of climate change on occupational injury risk. Among the 406 identified, 5 time-series and 3 case-crossover studies were selected for meta-analysis. RESULTS: Pooled risk estimates for time-series and case-crossover studies combined, and then separated, were 1.005 (95%CI: 1.001-1009), 1.002 (95%CI: 0.998-1.005), and 1.014 (95%CI: 1.012-1.017), respectively. Subgroup analyses found increased risks (not statistically significant) for male gender, age <25 years and agriculture. CONCLUSIONS: The present findings can orient further research to assess the effects of heat at workplace and consequently to establish better health policies for managing such exposure in at-risk regions.

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.

Occupational diseases in Italian national priority contaminated sites.

BACKGROUND: The aim of this study was to evaluate the occupational health risks in the Italian National Priority Contaminated Sites (NPCSs). METHODS: Established cases of occupational diseases in 2010-2014 were extracted from the Italian National Institute for Insurance against Accidents at Work (INAIL) archives. Standardized incidence ratios with 95% confidence intervals were estimated by site and by disease group separately for genders. RESULTS: In the 44 NPCSs evaluated, 11 015 cases of occupational diseases (8877 in men and 2138 in women) were ascertained. Overall, an excess of occupational diseases with respect to expected cases of 24.2% was found in men residing in NPCSs. An increased occurrence was detected in 21 NPCSs for men and in eight for women. CONCLUSIONS: The findings suggest a role of occupational diseases in the health profile of NPCSs, reinforcing the need for a permanent surveillance system.

Sinonasal cancer in the Italian national surveillance system: Epidemiology, occupation, and public health implications.

BACKGROUND: Sinonasal cancer (SNC) is a rare tumor with predominant occupational etiology associated with exposures to specific carcinogens. The aim of this study is to describe SNC cases recorded in Italy in the period 2000-2016. METHODS: Clinical information, occupational history, and lifestyle habits of SNC cases collected in the Italian Sinonasal Cancer Register were examined. Age-standardized rates were estimated. RESULTS: Overall, 1529 cases were recorded. The age-standardized incidence rates per 100 000 person-years were 0.65 in men and 0.26 in women. Occupational exposures were predominant among the attributed exposure settings, primarily to wood and leather dusts. Other putative causal agents included chrome, solvents, tannins, formaldehyde, textile dusts, and pesticides. Many cases had unknown exposure. CONCLUSIONS: Epidemiological surveillance of SNC cases and their occupational history is fundamental for monitoring the occurrence of the disease in exposed workers in industrial sectors generally not considered at risk of SNC as well as in non-occupational settings.

[National epidemiological surveillance systems of mesothelioma cases]. / I sistemi nazionali di sorveglianza dei casi di mesotelioma.

INTRODUZIONE: sebbene la relazione causale tra esposizione ad amianto e malattie neoplastiche sia ben nota, in molti Paesi il consumo del materiale è ancora rilevante e crescente. A causa della lunga latenza, nei Paesi dove è stato bandito (come in Italia) è oggi in corso un'epidemia di malattie correlate ad amianto. OBIETTIVI: descrivere i sistemi di sorveglianza dei mesoteliomi attivi nel mondo mediante un'analisi comparativa. METODI: è stata condotta una revisione bibliografica della letteratura disponibile sui sistemi di sorveglianza epidemiologica dei mesoteliomi attivi nel mondo, comparando metodi e risultati disponibili. RISULTATI: sistemi di ricerca dei casi incidenti e di analisi anamnestica dei soggetti ammalati sono attivi solo in Italia, Francia e Corea del Sud. I Paesi presso i quali sono attivi sistemi di rilevazione e controllo dei casi incidenti di mesotelioma sono quelli in cui vige il bando dell'amianto e che hanno sperimentato consumi rilevanti in passato. Non sono stati istituiti sistemi epidemiologici di sorveglianza in molti Paesi dove il consumo di amianto è ancora importante (inclusi Russia, Cina, India e Brasile). CONCLUSIONI: si conferma l'importanza dei sistemi di sorveglianza epidemiologica dei mesoteliomi per la sanità pubblica, il sostegno alle politiche di welfare e la prevenzione dei rischi. Lo sviluppo di progetti per tendere a una maggiore uniformità nei metodi di ricerca dei casi, di classificazione delle diagnosi e dell'esposizione e nelle tecniche di analisi dei dati potrebbe consentire una maggiore fruibilità dei dati aggregati. La disponibilità di dati internazionali confrontabili può essere di stimolo all'adozione di provvedimenti di bando internazionale.

[SENTIERI-ReNaM: Rationale and objectives]. / SENTIERI-ReNaM: Razionale e obiettivi.

The purpose of the SENTIERI-ReNaM Project is to analyse the incidence of mesothelioma in Italian National Priority Contaminated Sites (NPCSs) in order to estimate the health impact of asbestos on resident populations, disentangling the role of occupational and environmental exposures. SENTIERI Project has provided the relevant information on geographic and demographic structure of NPCSs and on existing sources of contamination. The Italian National Mesothelioma Registry (ReNaM), that covers the whole country through its Regional Operational Centres (CORs), has made available the procedures for estimating the incidence of mesothelioma in NPCSs and for assessing occupational and environmental asbestos exposure of the individual cases. The synergy between these two epidemiological surveillance systems lay also the ground for communication programmes with the affected communities.

[SENTIERI-ReNaM: Materials and methods]. / SENTIERI-ReNaM: Materiali e metodi.

In the framework of SENTIERI Project, this study is aimed to identify excess risks of malignant mesothelioma (MM) in Italian National Priority Contaminated Sites (NPCSs) included in the national environmental remediation programme and to discuss the results by means of data available from the Italian National Mesothelioma Registry (ReNaM). Re- NaM has a regional structure with Regional Operational Centres (CORs) in charge of identifying mesothelioma incident cases and defining the asbestos exposure modalities thought an individual questionnaire. Starting from the 44 NPCSs selected in SENTIERI Project, we excluded Calabria and Sardinia Regions from the analyses (3 NPCSs). Furthermore, for 2 sites (Emarese in Valle d'Aosta and Tito in Basilicata) no incident MM cases have been detected in the considered period. Incident cases of MM and Standardized Incidence Ratios (SIR), with corresponding 90% confidence intervals, have been estimated in each NPCS, for both gender, in the period 2000-2011. Age-standardized rates of Italian geographical macro-areas (North- East, North-West, Centre, South and Islands) have been used to estimate expected cases. For every analyzed site, the occupational and non-occupational asbestos exposure modalities are discussed.

[SENTIERI-ReNaM: Burden of disease from mesothelioma in national priority contaminated sites in Italy]. / SENTIERI-ReNaM: Valutazione globale del carico di mesotelioma.

BACKGROUND: in Italy, National Priority Contaminated Sites (NPCSs) are defined as of concern for remediation; most of them are sites with a long-lasting industrial activity. OBJECTIVE: the study aims to estimate the burden of disease from mesothelioma in NPCSs. DESIGN: mesothelioma incidence in the period 2000-2011 was estimated for the populations residing in the 39 Italian NPCSs. Data were taken from the Italian National Mesothelioma Registry (ReNaM). NPCSs were ranked into risk groups (RGs) on the basis of the presence of the following asbestos-exposing activities: 1. asbestos-cement plants; 2. asbestos mines; 3. harbours with shipyards; 4. illegal dumping sites containing asbestos; 5. petrochemicals and/or refineries, and/or steel plants; 6. chemical plants and/or landfills without explicit mention of asbestos. For the population residing in each NPCS, crude rates per 100,000 per year and number of observed minus expected cases (Obs-Exp) by gender were computed. Expected cases were calculated using the age-class rates of a reference population (the geographical macroarea of every NPCS). For every RG, the meta-analytic estimate of the attributable proportion (AP), i.e., the proportion of cases attributable to the local context, was computed, being the AP for each NPCS expressed as (Obs-Exp/Obs) x100. RESULTS: the total number of mesothelioma cases estimated in the considered period of 12 years is 2,741 (2,048 males, 693 females). The total number of Obs-Exp cases was 1,531 (1,178 in males, 353 in females). In males, crude rate ranges from 71.5 in the RG1 to 3.0 in RG4, while in females it ranges from 48.4 in RG1 to 0.6 in RG4. In males, AP in RGs from 1 to 3 is over 65%, in RG4 is 59%, in RG5 is 30%, in RG6 is -14%. AP in females gradually drops from 95% in RG1 to -64% in RG6. CONCLUSIONS: the burden of mesothelioma in populations residing in NPCSs is high, with an AP gradient consistent with the a priori RG. This burden impacts on females in a different way: rates are lower than male ones; AP is similar to male ones in the RGs 1 and 3.

[SENTIERI-ReNaM: Results]. / SENTIERI-ReNaM: Risultati.

Mesothelioma incidence has been analyzed in National Priority Contaminated Sites (NPCSs) to estimate the health impact of asbestos exposure on resident people. The burden of professional and environmental exposures has been identified through data of the Regional Operational Centres (CORs), made available by the Italian National Mesothelioma Registry (ReNaM). An excess of mesothelioma incidence is confirmed in sites with a known past history of direct use of asbestos, such as Balangero, Casale Monferrato, Broni, Bari-Fibronit, and in coastal areas, where shipyards, harbours and other industries that involved a wide use of asbestos are represented (e.g., Trieste, La Spezia, Venice, and Leghorn). An excess of mesothelioma has been observed in settings where the asbestos is not mentioned as contaminant in the decree that included these sites among NPCSs, such as Cengio and Saliceto in Northern Italy; Falconara Marittima and the Bacino Idrografico Fiume Sacco in the Central Italy; the Litorale Domizio Flegreo and Agro Aversano, Milazzo, and Gela in the Southern Italy. Observed excess in the various NPCSs confirms the large-scale occurrence in contaminated Italian sites of a significant amount of total mesothelioma cases observed at national level. The analysis of occupational risk in epidemiological studies with an ecological design helps in defining the contribution of different factors to the overall risk.

[SENTIERI-ReNaM: Discussion and concluding remarks]. / SENTIERI-ReNaM: Discussione e considerazioni conclusive.

SENTIERI-ReNaM Project analysed the incidence of malignant mesothelioma (MM) for the period 2000-2011 in 39 National Priority Contaminated Sites (NPCSs), and assessed the overall impact of mesothelioma in different types of NPCSs. In the study period, 2,683 incident cases of malignant mesothelioma were recorded: 1,998 males (74.5%), 685 females (25.5%). Excluding cases with non attributable exposure and those non interviewed, exposure was identified in 1,926 cases (70% of all cases): 1,541 males (occupational exposure: 1,414; environmental exposure: 82), 385 females (occupational exposure: 103; environmental exposure: 141). Women experienced mainly environmental and domestic exposures to asbestos. Standard Incidence Ratio (SIR) excesses were observed in men in 27 out of 39 NPCSs and defects in the remaining 12; in women, 20 NPCSs showed SIR excesses, defects in 15; in 4 NPCSs no MM cases occurred among female population. The highest rates were found in NPCSs with asbestos-cement plants (Broni and Casale Monferrato), respectively, 98 per 100,000 per year and 68.6 in men, 72.1 and 45.8 in women. Excluding these two sites, the highest incidence rates were found in the group with harbours and shipyards, where the rates were, respectively, 13.2 among men and 2.5 among women. The results of this report will be communicated to national and local institutions, as well as to NPCSs resident populations.

Occupational exposure and sinonasal cancer: a systematic review and meta-analysis.

BACKGROUND: Sinonasal cancer (SNC) has been related to occupational exposures, but the relative risk associated to specific jobs and/or carcinogen exposures other than wood and leather dust is generally based on small or inadequate sample sizes and the range of observed estimates is large. This paper is aimed at investigating such relationship through a systematic review of the literature followed by a meta-analysis of studies meeting specific inclusion criteria. METHODS: Systematic search was made with PubMed, Google Scholar and Scopus engines using related keywords. Occupational exposures include wood and leather dust, formaldehyde, nickel and chromium compounds, textile industry, farming and construction. Meta-analysis of published studies after 1985 with a case-control or cohort design was performed, firstly using the fixed-effect model. Heterogeneity was assessed with the Q statistical test and quantified by the I(2) index. When the heterogeneity hypothesis appeared relevant, the random-effect model was chosen. Sources of heterogeneity were explored using subgroup analyses. RESULTS: Out of 63 reviewed articles, 28 (11 cohort, 17 case-control) were used in the meta-analysis. Heterogeneity among studies was observed and random-effects models were used. Exposure to wood dust results associated with SNC (RRpooled = 5.91, 95% CI: 4.31-8.11 for the case-control studies and 1.61, 95% CI: 1.10-2.37 for the cohort studies), as well as to leather dust (11.89, 95% CI: 7.69-18.36). The strongest associations are with adenocarcinomas (29.43, 95% CI: 16.46-52.61 and 35.26, 95% CI: 20.62-60.28 respectively). An increased risk of SNC for exposures to formaldehyde (1.68, 95% CI: 1.37-2.06 for the case control and 1.09, 95% CI: 0.66-1.79 for the cohort studies), textile industry (2.03, 95% CI: 1.47-2.8), construction (1.62, 95% CI: 1.11-2.36) and nickel and chromium compounds (18.0, 95% CI: 14.55-22.27) was found. Subset analyses identified several sources of heterogeneity and an exposure-response relationship was suggested for wood dust (p = 0.001). CONCLUSIONS: By confirming the strength of association between occupational exposure to causal carcinogens and SNC risk, our results may provide indications to the occupational etiology of SNC (not only wood and leather dusts). Future studies could be focused on specific occupational groups to confirm causative agents and to define appropriate preventive measures.

Epidemiological patterns of asbestos exposure and spatial clusters of incident cases of malignant mesothelioma from the Italian national registry.

BACKGROUND: Previous ecological spatial studies of malignant mesothelioma cases, mostly based on mortality data, lack reliable data on individual exposure to asbestos, thus failing to assess the contribution of different occupational and environmental sources in the determination of risk excess in specific areas. This study aims to identify territorial clusters of malignant mesothelioma through a Bayesian spatial analysis and to characterize them by the integrated use of asbestos exposure information retrieved from the Italian national mesothelioma registry (ReNaM). METHODS: In the period 1993 to 2008, 15,322 incident cases of all-site malignant mesothelioma were recorded and 11,852 occupational, residential and familial histories were obtained by individual interviews. Observed cases were assigned to the municipality of residence at the time of diagnosis and compared to those expected based on the age-specific rates of the respective geographical area. A spatial cluster analysis was performed for each area applying a Bayesian hierarchical model. Information about modalities and economic sectors of asbestos exposure was analyzed for each cluster. RESULTS: Thirty-two clusters of malignant mesothelioma were identified and characterized using the exposure data. Asbestos cement manufacturing industries and shipbuilding and repair facilities represented the main sources of asbestos exposure, but a major contribution to asbestos exposure was also provided by sectors with no direct use of asbestos, such as non-asbestos textile industries, metal engineering and construction. A high proportion of cases with environmental exposure was found in clusters where asbestos cement plants were located or a natural source of asbestos (or asbestos-like) fibers was identifiable. Differences in type and sources of exposure can also explain the varying percentage of cases occurring in women among clusters. CONCLUSIONS: Our study demonstrates shared exposure patterns in territorial clusters of malignant mesothelioma due to single or multiple industrial sources, with major implications for public health policies, health surveillance, compensation procedures and site remediation programs.

Malignant mesothelioma due to non-occupational asbestos exposure from the Italian national surveillance system (ReNaM): epidemiology and public health issues.

INTRODUCTION: Italy produced and imported a large amount of raw asbestos, up to the ban in 1992, with a peak in the period between 1976 and 1980 at about 160,000 tons/year. The National Register of Mesotheliomas (ReNaM, "Registro Nazionale dei Mesoteliomi" in Italian), a surveillance system of mesothelioma incidence, has been active since 2002, operating through a regional structure. METHODS: The Operating Regional Center (COR) actively researches cases and defines asbestos exposure on the basis of national guidelines. Diagnostic, demographic and exposure characteristics of non-occupationally exposed cases are analysed and described with respect to occupationally exposed cases. RESULTS: Standardised incidence rates for pleural mesothelioma in 2008 were 3.84 (per 100,000) for men and 1.45 for women, respectively. Among the 15,845 mesothelioma cases registered between 1993 and 2008, exposure to asbestos fibres was investigated for 12,065 individuals (76.1%), identifying 530 (4.4%) with familial exposure (they lived with an occupationally exposed cohabitant), 514 (4.3%) with environmental exposure to asbestos (they lived near sources of asbestos pollution and were never occupationally exposed) and 188 (1.6%) exposed through hobby-related or other leisure activities. Clusters of cases due to environmental exposure are mainly related to the presence of asbestos-cement industry plants (Casale Monferrato, Broni, Bari), to shipbuilding and repair activities (Monfalcone, Trieste, La Spezia, Genova) and soil contamination (Biancavilla in Sicily). CONCLUSIONS: Asbestos pollution outside the workplace contributes significantly to the burden of asbestos-related diseases, suggesting the need to prevent exposures and to discuss how to deal with compensation rights for malignant mesothelioma cases induced by non-occupational exposure to asbestos.