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Pietro Comba

Publications and source records attributed to Pietro Comba.

At least 19 recordsLinked to original sources

Fluoro-edenitic fibres in the sputum of subjects from Biancavilla (Sicily): a pilot study.

BACKGROUND: An excess of mortality for malignant neoplasms of the pleura in Biancavilla, promoted an investigation for pleural mesothelioma, disclosing 17 cases. As the absence of known sources of asbestos exposure, a local stone quarry, located near the inhabited area, used for the extraction of building materials, was investigated. Amphibolic fibres were found in the quarry and identified as fluoro-edenite "new end-member of the edenite / fluoro-edenite series" and recognized as the fluoro-edenite holotype by International Mineralogical Association--Commission on New Minerals and Mineral Names. A pilot study was performed to verify the feasibility of using spontaneous sputum as an exposure indicator for these fibres, in a context in which the use of aerosol-induced sputum technique would not be easily accepted. METHODS: Hypothesizing a behaviour of the new fibre analogous to that of asbestos, the determination of the free fibres and the ferruginous bodies in spontaneous sputum was carried out. Phase Contrast Optical Microscope and an Environmental Scanning Electron Microscope fitted with X-ray energy dispersive analysis system (micro-analysis) were used to examine the samples. The criteria for inclusion in the study were: 1) subjects hospitalized for exacerbation of chronic obstructive pulmonary disease symptoms, 2) age > or = 45 years, 3) residence in Biancavilla for at least 30 years. RESULTS: The preliminary findings are related to 12 subjects (7 females and 5 males). Uncoated fibres (with length > 5 microm, diameter < 3 microm, aspect ratio 3.1) and ferruginous bodies were searched. Six out of twelve subjects (4 females, 2 males) had at least one of the three samples positive for the presence of fluoro-edenite, confirmed by micro-analysis. The fibre concentration found in the sputum ranged from 0.04 to 10 fibres/g; the length from 20 to 40 microm, the diameter was < 0.5 microm. No ferruginous bodies were found in any of the samples. The four women with a positive sample were housewives. Of the two men with a positive sample, one was a farmer and the other a mason. Therefore, it may be assumed that the exposure to fluoro-edenitic fibres was mainly environmental. CONCLUSION: The occurrence of the pleural mesothelioma cases and the presence of fluoro-edenitic fibres in spontaneous sputum, evidence the need to study the biological activity of fluoro-edenitic fibres and the implementation of epidemiological monitoring systems.

Asbestos, Amphibole↗

A cohort mortality study of leather tanners in Tuscany, Italy.

BACKGROUND: Work in leather tanning may involve exposure to a wide range of chemicals. Some of these are carcinogens or suspected carcinogens. Increased risk for a number of cancers have been reported, although there are considerable inconsistencies between studies. The present study investigates the mortality of leather tanners in Tuscany, Italy. METHODS: Tanneries were selected from the 1996 Valdarno Inferiore Tanneries Census and were in operation since December 31, 1970. Employees were followed until December 31, 1998 through company records, and the National and Regional Death Index. Demographic and work history data were abstracted from company payrolls. Regional mortality rates were used to calculate Standardized Mortality Ratio (SMR). Analyses were completed for the overall cohort (men and women) and for men who ever worked as of finisher, chrome tanners, and vegetable tanner (only men). RESULTS: The cohort consisted of 4,874 workers (4,150 males and 724 females) employed in 92 tanneries active in 1996 and operating on December 31, 1970. Ascertainment of vital status and cause of death were completed for all individuals by the end of follow-up, December 31, 1998. Males showed increases for cancer of the endocrine glands (SMR 5.67, 4 observed (obs), 90% Confidence Intervals (CI) 195-1,308), blood diseases (SMR 3.29, 4 obs, 90% CI 112-753), mental disorders (SMR 1.95, 6 obs, 90% CI 85-385), violence and accidents (SMR 1.30, 54 obs, 90% CI 102-163). Mortality from myeloid leukemia was increased in males (SMR 2.08, 5 obs, 90% CI 82-437) and in females (SMR 5.99, 2 obs, 90% CI 106-1,887). One death from nasal cancer was observed versus 0.2 expected. Mortality from lung cancer was increased among finishers (SMR 1.45, 19 obs, 90% CI 95-212), an increase was observed also for bladder cancer (SMR 1.25, 2 obs, 90% CI 22-393) and pancreatic cancer (SMR 1.20, 2 obs, 90% CI 21-379). CONCLUSIONS: The study confirms previous observations among tanners of increased mortality from lung, bladder, and pancreatic cancer. Noteworthy are the increased mortality from myeloid leukemia together with the new findings of an increased mortality from endocrine glands tumors, blood diseases, and psychiatric disorders which should be considered with caution because of the small number of cases and the novelty of the observation.

Accidents↗

Adverse health effects of fluoro-edenitic fibers: epidemiological evidence and public health priorities.

Subsequent to the detection of a cluster of mesothelioma cases in the Sicilian town of Biancavilla, located at the slopes of Etna volcano, ad hoc epidemiological studies and environmental monitoring suggested an etiological role of an asbestiform fiber present in a stone quarry. The fiber was shown to constitute a new mineral species named fluoro-edenite. Fluoro-edenitic fibers were found in the materials extracted from the quarry and used in the local building industry, as well as in soils. Besides the risk of mesothelioma, residents in Biancavilla showed a significantly increased mortality from chronic obstructive pulmonary disease, which was particularly evident among women. In the light of these findings, Biancavilla was defined a site of national interest for environmental reclamation. The first preventive action involved termination of quarrying activity, covering with asphalt of roads previously paved with local soil materials, and removal of sources of dust in the urban area. Concurrent to the implementation of environmental cleanup, some specific "second generation" studies are now being designed and performed, namely morbidity surveys based on hospital discharge cards, monitoring of fibers in sputum and health surveillance in selected population groups. In this frame, special emphasis is given to the issue of communication, both to the general public and to target groups like family doctors, teachers, and media professionals. This experience could represent a useful basis for the elaboration of a strategy to approach similar environmental issues.

Asbestos↗

Cancer mortality in an area of Campania (Italy) characterized by multiple toxic dumping sites.

Several recent studies have documented that a widespread practice of dumping toxic wastes has taken place for many years in the Provinces of Naples and Caserta. Extensive programs of environmental monitoring are currently ongoing in the area. In this frame, the Department of Civil Defence of the Italian Government has appointed an ad hoc study group in order to assess the health status of the population resident in the area of interest. The first investigation performed by the study group has been a geographic study on cancer mortality and occurrence of malformations in 196 municipalities constituting the two Provinces. The study detected an area located in the southeastern part of the Province of Caserta and in the northwestern part of the Province of Naples, where cancer mortality and congenital malformations show significantly increased rates with respect to expected figures derived from the regional population. The area highlighted by the study is, in general terms, overlapping with the area where most illegal dumping of toxic wastes took place. It is now recommended that mortality studies be extended to take into account other health outcomes, to search for correlations with environmental exposures, and consider possible confounding factors.

Cohort Studies↗

Mortality study of employees in a factory of recovery and refining of catalytic converters in Rome, Italy.

The study objective is to describe cause specific mortality of employees in a plant engaged in production, recovery and refining of catalytic converters located in Rome. Previous epidemiological studies conducted in similar plants are not available. A total of 828 workers (642 males and 186 females) were followed up between 1956 and 31-12-2003. Cause specific standardized mortality ratio (SMR) and 90% confidence intervals (CI) were computed using regional rates for comparison. Among males hired between 1956 and 1993, followed up until 31/12/2003, mortality for all causes (SMR 0,8; 90% CI 0,7-1,0; 85 observed) and all neoplasms (SMR 0,6; 90% CI 0,42-0,87; 20 observed) is below expected; an increase is present for liver cirrhosis (SMR 2,74; 90% CI 1,47-5,1; 7 observed) and brain cancer (SMR 5,24; 90% CI 2,3-11,90; 4 observed). The present investigation complies with the proposed scientific standards for occupational cohort studies. The study was not prompted by well defined a priori hypotheses but it is included in a process intended to typify a potentially polluted site; the absence of a priori hypotheses and of previous epidemiological evidence, prevent from a causal interpretation of the increased mortality from liver cirrhosis and brain cancer. The implementation of cohort studies in industrial sites where industrial activities similar to the one here examined are present, are highly recommended.

Adult↗

Mortality from chronic obstructive pulmonary disease and pleural mesothelioma in an area contaminated by natural fiber (fluoro-edenite).

OBJECTIVES: The purpose of the present study was to investigate the association between mortality from chronic obstructive pulmonary disease (COPD) and exposure to fluoro-edenite, a newly discovered amphibolic fiber found in Biancavilla (Sicily), a municipality on the slope of the Etna volcano, where a high mortality from malignant mesothelioma had been previously observed. METHODS: Thirty-six municipalities located in the volcanic area of mount Etna were selected for study. An ecological regression model was applied with mortality from COPD as the dependent variable, mortality from mesothelioma as a proxy for exposure to fluoro-edenite, and lung cancer mortality, an urban-rural index, a deprivation index and an aging index as the predictors of COPD mortality. For each municipality, risk classes were determined for the continuous variables with the use of a finite mixture model. RESULTS: A significant association was found between COPD mortality and pleural neoplasm mortality among the women in this study. The association was less consistent for the men. CONCLUSIONS: Despite the limitations of this ecological study, the results cohere with the results of toxicologic and observational studies and suggest an etiologic role for fluoro-edenite in nonmalignant respiratory diseases.

Adult↗

Comparison of Bayesian-utilitarian and maximin principle approaches.

The Precautionary Principle implies the adoption of a set of rules aimed at avoiding possible future harm associated with suspected, but not ascertained, risk factors. Several philosophical, economical and societal questions are implied by precaution-based public health decision making. The purpose of the present paper is to specify the scope of the principle examining the notion of uncertainty involved, and the implication of different approaches to the decision-making process. The Bayesian-utilitarian approach and the approach based on the maximin principle will be considered, and the different meaning of prudence in the two settings will be discussed. In the Bayesian-utilitarian approach the small number of attributable cases will end up in a low average expected value, easily regarded as acceptable in a cost-benefit analysis. In a maximin approach, on the other hand, the issue will be to consider the high etiologic fraction of a rare disease in the highest category of exposure. In the light of the aforementioned cautions in interpretation, the core difference between the two approaches has to do with the choice between averaging knowledge or equitably distributing technological risks.

Bayes Theorem↗

[Pleural mesothelioma and environmental exposure to mineral fibres: the case of a rural area in the Basilicata region, Italy].

The main aspects of the sites characterized by environmental exposure to mineral asbestiform fibres are described. Several adverse health effects including high incidence of pleural mesothelioma are reported. The average concentration of airborne fibres is generally low but it rises significantly in association with mechanical disturb of materials with fibres. Multiple sources of exposure have been identified, fibres can be found in the soil and in many materials locally used, mainly in buildings. Three mesothelioma cases were observed in a small rural area of the Basilicata region (Italy). Two of them had a possible occupational exposure to asbestos, the third had a proved environmental exposure to tremolite. This fibre, found in the area, is the same observed in two of the three biological samples analysed.

Asbestos↗

[The role of high risk groups in environmental health research].

High risk groups in environmental epidemiology are characterized by particularly high exposure levels with respect pollutant agents occurring in the various environmental matrices. An investigation of these groups may offer elements of interest also for the general population, which is exposed to lower levels of the agents at study, besides providing the evidence needed in order to implement appropriate remedial action. The discussion of four case-studies concerning populations resident in the neighbourhood of waste dump sites, power lines, incinerators and in areas with presence of fluoro-edenitic fibres, throws light on the rationale of studies on high risk groups. Special emphasis in placed on validity aspects, connections between epidemiologic studies and remediation interventions and ethical issues.

Biomedical Research↗

Pleural mesothelioma cases in Biancavilla are related to a new fluoro-edenite fibrous amphibole.

A cluster of deaths from pleural mesothelioma was previously reported for Biancavilla, Italy, a city in eastern Sicily. An environmental survey suggested that the stone quarries located southeast of the city might be a source of asbestos exposure. The materials extracted from the quarries, used widely in the local building industry, contain large quantities of a fibrous amphibole that was initially referred to as an anomalous intermediate phase of sodium- and fluorine-rich tremolite-actinolite. A subsequent crystal chemistry investigation identified the mineral as fluoro-edenite, a new end-member of the edenite --> fluoro-edenite series. The material is very similar in morphology and composition to the minerals of the tremolite-actinolite series. To the authors' knowledge, fluoro-edenite becomes the 3rd mineral fiber (along with erionite and winchite), not yet classified as asbestos, with a demonstrable mesotheliomatogenous action in humans.

Air Pollutants, Occupational↗

Sinonasal cancer and occupational exposures: a pooled analysis of 12 case-control studies.

OBJECTIVE: In order to examine the associations between sinonasal cancer and occupational exposures other than wood dust and leather dust, the data from 12 case-control studies conducted in seven countries were pooled and reanalyzed. METHODS: The pooled data set included 195 adenocarcinoma cases (169 men and 26 women), 432 squamous cell carcinomas (330 men and 102 women), and 3136 controls (2349 men and 787 women). Occupational exposures to formaldehyde, silica dust, textile dust, coal dust, flour dust, asbestos, and man-made vitreous fibers were assessed with a job-exposure matrix. Odds ratios (ORs) were adjusted for age, study, wood dust, and leather dust, or other occupational exposures when relevant. 95% confidence intervals (CIs) were estimated by unconditional logistic regression. RESULTS: A significantly increased risk of adenocarcinoma was associated with exposure to formaldehyde. The ORs for the highest level of exposure were 3.0 (Cl = 1.5-5.7) among men and 6.2 (CI=2.0-19.7) among women. An elevated risk of squamous cell carcinoma was observed among men (OR=2.5, CI=0.6-10.1) and women (OR = 3.5, CI = 1.2-10.5) with a high probability of exposure to formaldehyde. Exposure to textile dust was associated with non-significantly elevated risk of adenocarcinoma, among women only: the OR for the high level of cumulative exposure was 2.5 (CI = 0.7-9.0). High level of asbestos exposure was associated with a significantly increased risk of squamous cell carcinoma among men (OR = 1.6, CI = 1.1-2.3). CONCLUSIONS: The results of this pooled analysis support the hypothesis that occupational exposure to formaldehyde increases the risk of sinonasal cancer, particularly of adenocarcinoma. They also indicate an elevated risk of adenocarcinoma among women exposed to textile dust, and suggest that exposure to asbestos may increase the risk of squamous cell carcinoma.

Adenocarcinoma↗

Malignant mesothelioma in Rome and Latium region, 1993-2001.

AIMS AND BACKGROUND: Epidemiological studies on malignant mesothelioma have provided evidence on the etiologic role of occupational asbestos exposure and, to some extent, domestic and residential exposures. Less attention has been given to the occurrence of mesothelioma in urban areas where large quantities of asbestos have been employed in the past. The purpose of the study was to investigate the occurrence of mesothelioma in patients living in the urban area of Rome and in other parts of the Latium Region and the patterns of asbestos exposure. METHODS AND STUDY DESIGN: A pathology-based, malignant mesothelioma archive operating in Rome, Italy, was the source of cases. Included in the survey were cases resident in Latium and diagnosed in the period January 1, 1993, through December 31, 2001. Information on asbestos exposure was derived from interviews to the patient or his/her next of kin and from available medical records. RESULTS: The case series included: 114 males and 53 females; total, 167. Information on asbestos exposure was available for 138 cases (83%). Occupational exposure was ascertained or suspected for 33% of cases resident in Rome and 63% of those resident in other municipalities of Latium. Sex ratio was 1.6 in Rome and 3.3 in Latium. CONCLUSIONS: The high prevalence of women among mesothelioma cases and lower proportion of occupational exposure in Rome versus the other municipalities of Latium suggest a possible role of environmental asbestos exposure in the urban area.

Adult↗

Asbestos-related diseases in Italy: epidemiologic evidences and public health issues.

Epidemiologic information about asbestos-related diseases in Italy, derived from mortality data, epidemiologic surveillance, and analytical studies, is presented. These systems evidence exposures to asbestos and relative risks for populations exposed in work environments and also in the general environment, and provide objective data to identify sources of exposure and for risk management. Limitations and perspectives of Italian studies are considered, and public health issues evaluated: the risk for migrants, social security aspects, and asbestos-related disease in the courts. Although asbestos use was banned in 1992, information and risk communication efforts should be implemented to empower affected individuals and communities and to pursue equitable allocation of resources for primary prevention and health surveillance.

Asbestos↗

[Mortality study of a cohort of insulation workers].

Cause specific mortality was investigated in a cohort of insulators employed by a company which operated in various parts of Italy. Follow-up covered the years 1960-1996. The cohort, which included 893 subjects, was derived from company files of relatively poor quality, which resulted in a high rate of lost to follow-up (10.1%) and of deaths with unknown cause (12.4%). The mortality experience of the cohort was contrasted with that of the Italian population. Overall mortality (SMR 141, 90% CI 118-167, 97 observed), and cancer mortality (SMR 165, 90% CI 123-216, 38 observed) were significantly increased. Among neoplasms, significant increases were observed for lung cancer (SMR 202, 90% CI 124-311, 15 observed), pleural neoplasms (SMR 2667, CI 90% 911-6103, 4 observed), and peritoneal neoplasms (SMR 1853, 90% CI 329-5832, 2 observed). The excess mortality for lung cancer was especially pronounced in subjects with latency time longer than ten years (SMR 237.1, 90% CI 140-377, 13 observed).

Adult↗